JP2022076973A - Injector and cast machine - Google Patents

Abstract

To provide an injector for which hydraulic and electric-powered types are both usable.SOLUTION: An injector 9 comprises an injection cylinder 27 that is coupled to a rear end of a plunger 21, a hydraulic device 43 that supplies working fluid to the injection cylinder 27, an electric-powered first drive device 29A that is detachably attached to a piston rod 39 of the injection cylinder 27, and a control device 5 that commences injection by starting an advancement of the piston 37 through supplying working fluid to a head-sided chamber 35h from an accumulator 47. The control device 5 is configured to perform control to retract a movable member 69 by a first electric motor 31A of the first drive device 29A in a state that the movable member 69 is inhibited from retracting relative to the piston rod 39 by an attachment/detachment unit 33, thereby forcing the working fluid of the injection cylinder 27 to the accumulator 47 by the retracting piston 37 of the injection cylinder 27.SELECTED DRAWING: Figure 3

Description

The present disclosure relates to an injection device and a molding machine including the injection device. The molding machine is, for example, a die casting machine or an injection molding machine.

There is known an injection device that pushes the molding material in the sleeve leading to the inside (cavity) of the mold into the inside of the mold by a plunger sliding in the sleeve. Examples of the drive system of the plunger include a hydraulic type using a hydraulic cylinder (for example, a hydraulic type), an electric type using an electric motor, and a hybrid type in which both are combined. The following Patent Documents 1 to 3 propose a specific configuration of a hybrid injection device.

Japanese Unexamined Patent Publication No. 2008-279494 Japanese Unexamined Patent Publication No. 2012-179609 Japanese Unexamined Patent Publication No. 2011-235295

The hydraulic type and the electric type have advantages and disadvantages when compared with each other. For example, in the hydraulic type, it is easy to drive the plunger at high speed by supplying a high-pressure hydraulic fluid from the accumulator to the hydraulic cylinder. The electric type is advantageous for, for example, reducing power consumption, improving the accuracy of control related to the movement of the plunger, and reducing the environmental load (for example, reducing oil). The various hybrid injection devices proposed so far are configured to take advantage of each of the hydraulic and electric types. However, since the performance required for the injection device differs depending on the user, a new hybrid injection device that can suitably use the hydraulic drive unit and the electric drive unit is proposed, and the technology is enriched. Is preferable.

The injection device according to one aspect of the present disclosure has an injection cylinder connected to the rear end of a plunger that advances in a sleeve extending in the front-rear direction and pushes a molding material into the inside of a mold, and a hydraulic fluid is applied to the injection cylinder. It has a hydraulic pressure device to be supplied, a first drive device for connecting and disconnecting the injection cylinder, and a control device for controlling the hydraulic pressure device and the first drive device, and the injection cylinder. Has a piston rod connected to the rear end of the plunger, a piston connected to the rear end of the piston rod, and a space for slidably accommodating the piston in the front-rear direction. However, the piston has a rod side chamber in which the piston rod is located and a cylinder member partitioned into a head side chamber on the opposite side thereof, and the hydraulic pressure device is provided in the head side chamber. It has a first accumulator that supplies the hydraulic fluid and a hydraulic circuit that controls the flow of the hydraulic fluid between the first accumulator and the head side chamber, and the first drive device is a first electric motor. A movable member driven in the front-rear direction by the first electric motor, and a detachable portion for allowing and prohibiting the retract of the movable member with respect to the piston rod, and the control device is provided with the detachable portion. By supplying the hydraulic fluid from the first accumulator to the head side chamber in a state where the movable member is allowed to retract with respect to the piston rod, control is performed to start the advance of the piston and start injection. In a state where the movable member is prohibited from retreating with respect to the piston rod by the detachable portion, the movable member is retracted by the first electric motor, and the piston retracting the movable member causes the hydraulic fluid in the head side chamber to be discharged. 1 It is configured to control pushing to the accumulator.

The molding machine according to one aspect of the present disclosure includes the injection device and a mold clamping device for opening / closing and clamping the mold.

According to the above configuration, the hydraulic drive unit and the electric drive unit can be suitably used.

The side view which shows the structure of the main part of the die casting machine which concerns on 1st Embodiment. The top view which shows the structure of the main part of the die casting machine of FIG. FIG. 6 is a cross-sectional view schematically showing a configuration of a main part of an injection device included in the die casting machine of FIG. The circuit diagram which shows the structure of the hydraulic pressure apparatus which the injection apparatus of FIG. 3 has. 5 (a) and 5 (b) are views showing an example of a detachable portion of the injection device of FIG. The figure explaining the operation of the injection apparatus of FIG. The figure which shows the structure of the main part of the injection apparatus which concerns on 2nd Embodiment. The side view which shows the structure of the main part of the die casting machine which concerns on 3rd Embodiment. The top view which shows the structure of the main part of the die casting machine of FIG. FIG. 8 is a cross-sectional view schematically showing a configuration of a main part of an injection device included in the die casting machine of FIG. The circuit diagram which shows the structure of the hydraulic pressure apparatus which the injection apparatus of FIG. 10 has. The figure explaining the operation of the injection apparatus of FIG. The figure which shows the structure of the hydraulic pressure apparatus which the injection apparatus which concerns on 4th Embodiment has. FIG. 3 is a cross-sectional view schematically showing a configuration of a flow rate control valve and a check valve included in the hydraulic pressure device of FIG. FIG. 6 is a cross-sectional view schematically showing the configurations of a flow rate control valve and a check valve in a state different from FIG. FIG. 6 is a cross-sectional view schematically showing the configurations of a flow rate control valve and a check valve in a state different from those in FIGS. 13 and 14. The figure which shows the structure of the main part of the injection apparatus which concerns on the 1st modification. 18 (a) and 18 (b) are views showing the configuration of a main part of the injection device according to the second and third modifications.

Hereinafter, a plurality of embodiments and modifications according to the present disclosure will be described with reference to the drawings. In the description of the embodiments and modifications other than the first embodiment, basically, only the differences from the embodiments or modifications described above will be described. Matters not particularly mentioned may be the same as those of the embodiment or modification described above, or may be inferred from the embodiment or modification described above. Further, for the configurations corresponding to each other in the plurality of embodiments and modifications, the same reference numerals may be given to each other for convenience even if there are differences.

In one embodiment, the injection device has a first drive device 29A and a second drive device 29B. Further, in another embodiment, the injection device has a first drive device 29A and no second drive device 29B. Therefore, for the convenience of facilitating the understanding of the configuration common to the embodiments, the existence of the second drive device 29B such as the "first drive device 29A" is recalled even in the embodiment without the second drive device 29B. May be used. Taking the drive unit as an example, the same applies to other components.

<First Embodiment>
(Overall configuration of die casting machine)
FIG. 1 is a side view (including a cross-sectional view in part) showing a configuration of a main part of the die casting machine 501 according to the first embodiment. FIG. 2 is a top view showing the configuration of a main part of the die casting machine 501. In each figure, the illustration of various members is omitted for convenience. Therefore, for example, the illustration of the components that are shown in FIG. 1 and should be visible in FIG. 2 may be omitted in FIG. The reverse is also true. In the following description, for convenience, the left side of the paper in FIGS. 1 and 2 may be referred to as the front, and the right side of the paper in FIG. 1 may be referred to as the rear.

The die casting machine 501, for example, injects (fills) a molten molding material into the inside (cavity 107) of the mold 101 (FIG. 1) to produce a product (molded product, die casting product) made of solidified molding material. It is configured as a manufacturing device.

The molding material is, for example, a metal such as aluminum. The molten metal is sometimes called a molten metal. Instead of the molded material in the molten state, the molding material in the solid-liquid coexisting state (semi-solidified state or semi-melted state) may be injected into the cavity 107.

The mold 101 has, for example, a fixed mold 103 and a moving mold 105 facing the fixed mold 103. The cavity 107 into which the molding material is injected is formed between the fixed mold 103 and the moving mold 105. The fixed mold 103 is a mold that does not move. The moving mold 105 is a mold that moves in a direction facing the fixed mold 103 (mold opening / closing direction). The mold opening / closing direction is, for example, the horizontal direction.

The die casting machine 501 has a machine main body 503 that performs mechanical operation and a control device 5 that controls the machine main body 503. The machine main body 503 is, for example, a mold clamping device 7 that opens and closes and clamps the mold 101, an injection device 509 that injects molten metal into the cavity 107, and a fixed mold 103 that is composed of solidified molten metal. Alternatively, it has an extruder (not shown) that extrudes from the moving die 105. The control device 5 may be regarded as a component of the injection device 509.

In the die casting machine 501, except for the configuration and operation of the injection device 509, the configuration and operation of other components (for example, the mold clamping device 7 and the extrusion device) are various configurations and operations including known configurations and operations. It's okay. From another point of view, the operation of the injection device 509 is the control of the injection device 509 by the control device 5. Therefore, the description of the configuration and operation of the other components will be omitted as appropriate. Hereinafter, the configuration and operation of the mold clamping device 7 and the configuration of the control device 5 will be briefly described. After that, the configuration and operation of the injection device 509 will be described.

The mold clamping device 7 is inserted into, for example, a base 11, a fixed die plate 13 fixed on the base 11, a moving die plate 15 that can move in the mold opening / closing direction on the base 11, and these die plates. It has a plurality of (for example, four) tie bars 17 and the like. The fixed die plate 13 and the moving die plate 15 face each other in the mold opening / closing direction. The fixed die plate 13 holds the fixed mold 103 on the surface facing the moving die plate 15. The moving die plate 15 holds the moving mold 105 on a surface facing the fixed die plate 13. The mold 101 is opened and closed by moving the moving die plate 15 in the mold opening / closing direction. Further, by extending the tie bar 17 in a state where the mold is closed, a mold clamping force corresponding to the extension amount is applied to the mold 101.

The control device 5 may be configured to include, for example, a computer, although not particularly shown. The computer may be configured to include, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and an external storage device, although not particularly shown. By executing the program stored in the ROM and / or the external storage device by the CPU, various functional units that perform various operations (including control) are constructed. Further, the control device 5 may include a logic circuit that executes a certain operation, may include a power supply circuit, or may be conceptualized including a driver. The control device 5 may be integrated in one place in terms of hardware, or may be distributed in a plurality of places.

(Injection device)
The injection device 509 is located behind the fixed die plate 13 (opposite the moving die plate 15). The injection device 509 has a sleeve 19 leading to the cavity 107, a plunger 21 for pushing the molten metal in the sleeve 19 into the cavity 107, and a drive unit 523 for driving the plunger 21. Since the sleeve 19 and the plunger 21 can be regarded as consumables, only the drive unit 523 may be regarded as an injection device.

The configurations of the sleeve 19 and the plunger 21 may be various configurations including known configurations. In the illustrated example, it is as follows.

The sleeve 19 is provided so as to be inserted through the fixed die plate 13. The sleeve 19 may not be inserted into the fixed mold 103 (example in the figure), or may be inserted. The sleeve 19 is a substantially cylindrical member, and is arranged so as to extend in the horizontal direction (front-back direction). A supply port 19a to which the molten metal is supplied is opened on the upper surface of the sleeve 19.

The plunger 21 has a plunger tip 21a that slides on the sleeve 19 and a plunger rod 21b that is fixed to the plunger tip 21a. The plunger rod 21b extends in the front-rear direction, and its rear end is connected to the drive unit 523 by a coupling 25.

1 and 2 show the state before the start of injection. At this time, the plunger tip 21a is located (at least partially) in the sleeve 19 behind the supply port 19a. In this state, the molten metal is poured into the supply port 19a by a hot water supply device (not shown) or the like. Next, the plunger tip 21a slides (advances) toward the cavity 107 by the driving force of the driving unit 523. As a result, the molten metal is ejected into the cavity 107.

(Drive part)
FIG. 3 is a cross-sectional view schematically showing the configuration of a main part of the injection device 509. This figure is a view of the injection device 509 as viewed from above.

The injection device 509 (drive unit 523) has an injection cylinder 527 connected to the rear end of the plunger 21 by a coupling 25. A hydraulic fluid (for example, oil) is supplied to the injection cylinder 527 from a hydraulic pressure device 543 (see FIG. 4 described later). As a result, the injection device 509 can apply a hydraulic driving force to the plunger 21.

Further, the injection device 509 has two first drive devices 29A including a first electric motor 31A, respectively. The first drive device 29A has a detachable portion 33 capable of connecting and disconnecting the injection cylinder 527 to the piston rod 39 described later. As a result, the injection device 509 can apply an electric driving force to the plunger 21.

(Injection cylinder)
The injection cylinder 527 is, for example, arranged coaxially with the plunger 21 behind the plunger 21. The injection cylinder 527 contains, for example, a cylinder member 535, a piston 37 slidable inside the cylinder member 535, a piston rod 39 extending forward (toward the plunger 21 side) from the piston 37, and a hydraulic fluid behind the piston 37. It has a pressurizing member 541 that can pressurize.

The cylinder member 535 is, for example, a roughly cylindrical member. The shape of the cross section inside the cylinder member 535 is, for example, circular. The outer shape (outer shape) of the cylinder member 535 may have an appropriate shape such as a rectangular parallelepiped shape. The cylinder member 535 is immovable with respect to the fixed die plate 13. The cylinder member 535 has a small-diameter cylinder 35x and a large-diameter cylinder 35y connected in series to the rear end of the small-diameter cylinder 35x. The inner diameter of the large diameter cylinder 35y is larger than the inner diameter of the small diameter cylinder 35x.

The piston 37 is, for example, a roughly columnar member. The diameter of the piston 37 is substantially the same as the inner diameter of the small diameter cylinder 35x. A packing (not shown) may be interposed between the piston 37 and the small diameter cylinder 35x. Even when the packing is interposed, it is expressed that the piston 37 slides in the small diameter cylinder 35x (cylinder member 535). The same applies to other members (for example, the pressurizing member 541). The space inside the small diameter cylinder 35x is partitioned by the piston 37 into a rod side chamber 35r on the piston rod 39 side and a head side chamber 35h on the opposite side.

The piston rod 39 is, for example, a roughly columnar member. The diameter of the piston rod 39 is smaller than the diameter of the piston 37. The difference may be set as appropriate. The piston rod 39 extends to the outside of the cylinder member 535, and its front end is connected to the rear end of the plunger 21 by a coupling 25.

The piston rod 39 moves integrally with the plunger 21. Therefore, the injection cylinder 527 is configured to be able to move the piston rod 39 (piston 37) with a stroke equal to or greater than the stroke assumed for the plunger 21.

The pressurizing member 541 is composed of, for example, a piston slidable on the cylinder member 535. More specifically, the pressurizing member 541 has a small-diameter piston 541a that slides on the small-diameter cylinder 35x and a large-diameter piston 541b that slides on the large-diameter cylinder 35y. The large diameter piston 541b is connected in series to the rear end of the small diameter piston 541a. Note that, unlike the illustrated example, a connecting portion having a diameter smaller than the diameter of the small diameter piston 541a may be formed between the small diameter piston 541a and the large diameter piston 541b.

The portion of the inside of the cylinder member 535 (35x and 35y) behind the piston 37 is divided into a head side chamber 35h on the piston 37 side and a rear chamber 35a on the opposite side by the pressurizing member 541. The inside of the large-diameter cylinder 35y is divided into a front chamber 35f on the small-diameter cylinder 35x side and a rear chamber 35a on the opposite side by a large-diameter piston 541b. The pressurizing member 541 has a first surface 541c (the tip surface of the small diameter piston 541a) that receives pressure from the hydraulic fluid of the head side chamber 35h and a second surface 541d (after the small diameter piston 541a) that receives pressure from the hydraulic fluid of the rear side chamber 35a. It has an end face). The area of the second surface 541d is larger than the area of the first surface 541c.

The injection cylinder 527 operates, for example, roughly as follows, and is also driven by the hydraulic pressure device 543 and the first drive device 29A.

As the piston 37 advances, the plunger 21 advances, and by extension, the molten metal in the sleeve 19 is ejected into the cavity 107. That is, injection in a narrow sense (injection not including the pressure increasing step described later) is performed. The advancement of the piston rod 39 for this injection is realized, for example, by supplying the hydraulic fluid from the hydraulic pressure device 543 to the head side chamber 35h. Then, the cavity 107 is generally filled with the molding material.

At least, after the cavity 107 is substantially filled with the molding material, the hydraulic fluid in the head side chamber 35h is pressurized by advancing the pressurizing member 541. As a result, for example, the plunger 21 applies pressure to the molten metal in the cavity 107 to increase the pressure of the molten metal. The advancement of the pressurizing member 541 is realized, for example, by supplying the hydraulic fluid from the hydraulic pressure device 543 to the rear side chamber 35a. Since the area of the second surface 541d of the pressurizing member 541 is larger than the area of the first surface 541c, a pressure higher than the pressure of the rear side chamber 35a can be applied to the head side chamber 35h.

After the molten metal in the cavity 107 solidifies, the piston rod 39 retracts, so that the plunger 21 retracts and returns to the position before injection. The retreat of the plunger 21 is realized by, for example, the first drive device 29A.

As can be understood from the above description, the head side chamber 35h and the rear side chamber 35a are filled with the hydraulic fluid. On the other hand, the rod side chamber 35r and the front side chamber 35f may or may not be filled with the hydraulic fluid. For example, the rod side chamber 35r and the front side chamber 35f may be open to the atmosphere. When the hydraulic fluid is not filled, a small amount of the hydraulic fluid (oil) may be arranged in the rod side chamber 35r and the front side chamber 35f for lubrication.

In the following description, an embodiment in which the rod side chamber 35r is filled with the hydraulic fluid will be taken as an example. The hydraulic fluid in the rod side chamber 35r contributes, for example, to reducing the probability that the piston 37 will advance (jumping) at a rapid speed at the start of injection, and / or to absorb the surge pressure when the filling of the molten metal is completed.

When the front chamber 35f is filled with the hydraulic fluid, the hydraulic fluid may or may not be used for some purpose. As an example of the former, for example, an embodiment in which a hydraulic fluid is supplied from the hydraulic pressure device 543 to the front side chamber 35f to apply a rearward driving force to the pressurizing member 541 can be mentioned. Further, for example, an embodiment may be mentioned in which the hydraulic fluid device 543 prohibits the discharge of the hydraulic fluid from the front chamber 35f and prohibits the unintended advancement of the pressurizing member 541. Further, as an example of the latter, an embodiment in which the front concubine 35f and the tank are only connected can be mentioned.

(flame)
The method of immovably installing the cylinder member 535 with respect to the fixed die plate 13 may be appropriate. In the example shown in FIGS. 1 and 2, the cylinder member 535 is connected to the fixed die plate 13 by the frame 45. As will be described later, the frame 45 also contributes to the support of the first drive device 29A and the like.

The shape of the frame 45 is arbitrary. For example, as shown in FIG. 1, the frame 45 is connected to a first portion 45a, which is located between the fixed die plate 13 and the cylinder member 535 and fixes the two, and is connected to the first portion 45a. It may have a second portion 45b that supports the cylinder member 535 from below.

The shapes of the first portion 45a and the second portion 45b are also arbitrary. For example, the first portion 45a is adjacent to a portion located below the plunger 21 (FIG. 1, reference numeral omitted), a portion located laterally and / or above the plunger 21 (FIG. 2), and the front end of the cylinder member 535. You may have a plate 45c (FIGS. 2 and 3) to be used.

(Hydraulic device)
FIG. 4 is a circuit diagram showing an example of a hydraulic pressure device 543 that supplies a hydraulic fluid to the injection cylinder 527 to drive the injection cylinder 527.

(Accumulator, pump and tank)
The hydraulic pressure device 543 has an accumulator 47 and a pump 49 as a hydraulic pressure source. Further, the hydraulic pressure device 543 has a tank 51 for storing the hydraulic fluid. The tank 51 is shown at a plurality of positions for convenience. In practice, the number of tanks 51 may be less than the number shown, for example only one.

The division of roles between the accumulator 47 and the pump 49 (and the tank 51) may be appropriately set.

In the present embodiment, the hydraulic fluid is supplied from the accumulator 47 to the head side chamber 35h, whereby the piston 37 advances and injection is performed. Further, the hydraulic fluid is supplied from the accumulator 47 to the rear chamber 35a, whereby the pressurizing member 541 moves forward to increase the pressure.

Filling of the accumulator 47 is realized by retracting the piston 37 by the first drive device 29A and pushing the hydraulic fluid of the head concubine 35h to the accumulator 47, as will be described in detail later. Further, the filling of the accumulator 47 prohibits the discharge of the hydraulic fluid from the head side chamber 35h in a part of the section where the piston 37 is retracted by the first drive device 29A (for example, the initial section of the displacement), and the pressurizing member 541. Is retracted and the hydraulic fluid in the rear chamber 35a is pushed out to the accumulator 47.

However, unlike the description of the present embodiment, the accumulator 47 may be filled by the first drive device 29A only by the hydraulic fluid discharged from the head side chamber 35h. For example, the hydraulic fluid in the rear chamber 35a may be discharged to the tank 51 while the pressure member 541 is retracted as described above. Further, the retreat of the pressurizing member 541 may be performed by supplying the hydraulic fluid to the head side chamber 35h and / or the front side chamber 35f by the pump 49, unlike the description of the present embodiment.

The pump 49 replenishes the rod side chamber 35r with the hydraulic fluid, for example, when the piston 37 is retracted by the first drive device 29A. Further, the pump 49 replenishes the hydraulic fluid to the front concubine 35f when the piston 37 is retracted by the first drive device 29A to retract the pressurizing member 541 in a state where the discharge of the hydraulic fluid from the head concubine 35h is prohibited. You may. Further, for example, the pump 49 contributes to replenishing the hydraulic fluid in an amount corresponding to the hydraulic fluid leaked in the injection cylinder 527 or the like, and / or supplying the hydraulic fluid in the maintenance of the injection device 509.

A rearward driving force is applied to the piston 37 by the first driving device 29A. Therefore, in the embodiment of supplying the hydraulic fluid from the pump 49 to the rod side chamber 35r, the force by which the hydraulic fluid in the rod side chamber 35r pushes the piston 37 backward is smaller than the force by which the hydraulic fluid in the head side chamber 35h pushes the piston 37 forward. It's okay. That is, the product of the pressure of the rod side chamber 35r and the area where the pressure acts on the piston 37 is the product of the pressure of the head side chamber 35h (accumulator 47 from another viewpoint) and the area where the pressure acts on the piston 37. May be smaller than. From another point of view, the pressure of the rod side chamber 35r to which the hydraulic fluid is replenished by the pump 49 may be low.

Specifically, for example, the force that the hydraulic fluid in the rod side chamber 35r pushes the piston 37 backward is the force that the hydraulic fluid in the head side chamber 35h pushes the piston 37 forward (the pressure of the accumulator 47 is before the piston 37 starts injection). It may be set to 2/3 or less, 1/2 or less, 1/5 or less, or 1/10 or less with respect to (the same applies in the next paragraph). Further, the pressure of the rod side chamber 35r may be equal to the tank pressure (pressure of the tank 51) and / or the atmospheric pressure, and may be slightly lower than these pressures.

The pressure of the rod side chamber 35r may be higher than the tank pressure and the atmospheric pressure. In this case, the pump 49 assists the retreat of the plunger 21 by the first drive device 29A. At this time, the force with which the hydraulic fluid in the rod side chamber 35r pushes the piston 37 backward may be appropriately set. For example, the force by which the hydraulic fluid in the rod side chamber 35r pushes the piston 37 backward is 1/10 or more, 1/5 or more, and 1/2 or more with respect to the force by which the hydraulic fluid in the head side chamber 35h pushes the piston 37 forward. Or it may be 2/3 or more. The lower bound in the previous paragraph may be combined with the lower bound in this paragraph as long as there is no conflict.

Further, the pressurizing member 541 is applied with a driving force rearward from the first driving device 29A via the hydraulic fluid of the piston 37 and the head side chamber 35h. Therefore, in the mode of supplying the hydraulic fluid from the pump 49 to the front side chamber 35f, it is not necessary to increase the pressure of the pump 49 as in the mode of supplying the hydraulic fluid to the rod side chamber 35r. In the above description of the pressure or force generated by the hydraulic fluid in the rod side chamber 35r, the rod side chamber 35r is replaced with the front side chamber 35f, the head side chamber 35h is replaced with the rear side chamber 35a, and the piston 37 is replaced with the pressurizing member 541. The pressure or force generated by the hydraulic fluid in the front chamber 35f may be used.

As described above, in the present embodiment, the accumulator 47 is basically not filled by the pump 49. Further, when the piston 37 (and the pressurizing member 541) is retracted, the pressure of the rod side chamber 35r (and the front side chamber 35f) to which the hydraulic fluid is supplied from the pump 49 may be low. Therefore, for example, the capacity of the pump 49 (the amount of the hydraulic fluid delivered in one cycle) may be smaller than that of a general hydraulic type or known hybrid type injection device. Further, since the hydraulic fluid is directly supplied to each other between the head side chamber 35h (and the rear side chamber 35a) and the accumulator 47, and the tank 51 does not intervene between them, the volume of the tank 51 can be reduced.

The accumulator 47 may be configured by an appropriate type of accumulator such as a weight type, a spring type, a gaseous pressure type (including a pneumatic type), a cylinder type, and a Prada type. For example, the accumulator 47 is a gas pressure type, cylinder type or Prada type accumulator, and the gas (for example, air or nitrogen) held in the accumulator 47 is compressed to accumulate pressure.

The pump 49 may be a rotary pump that discharges the hydraulic fluid by the rotation of the rotor, or may be a plunger pump that discharges the hydraulic fluid by the reciprocation of the piston. The pump 49 may be configured by a constant-capacity pump in which the discharge amount in one cycle of the rotor or the piston is fixed, or may be configured by a variable-capacity pump in which the discharge amount is variable. Further, although it is sufficient that the pump 49 can discharge the hydraulic fluid in one direction, the structure may be the same as that of the bidirectional (two-way) pump.

Although not particularly shown, the pump 49 is driven by, for example, a rotary motor. This electric motor may be a DC motor, an AC motor, an induction motor, or a synchronous motor. The electric motor may function as a constant-speed electric motor provided in an open loop, or may function as a servomotor provided in a closed loop. The electric motor (pump 49) may be driven only when necessary, or may be driven all the time.

The tank 51 is, for example, an open tank. That is, the tank 51 holds the hydraulic fluid under atmospheric pressure. Therefore, for example, when the rod side chamber 35r is connected to the tank 51, the pressure of the rod side chamber 35r drops to atmospheric pressure or a pressure close to the atmospheric pressure.

(Hydraulic circuit)
The hydraulic pressure device 543 includes a hydraulic pressure circuit 553 that controls the flow of the hydraulic fluid between the injection cylinder 527, the accumulator 47, the pump 49, and the tank 51. Various specific configurations of the hydraulic circuit 553 that realizes the division of roles between the accumulator 47 and the pump 49 as described above are possible. The configuration of the hydraulic circuit 553 shown in FIG. 4 is only an example.

Hereinafter, the hydraulic circuit 553 exemplified in FIG. 4 will be described in the following order. First, the flow path between the accumulator 47 and the head side chamber 35h will be described. Next, the flow path between the accumulator 47 and the rear concubine 35a will be described. Next, the flow path between the rod side chamber 35r and the tank 51 will be described. Next, the flow path between the pump 49 and the rod side chamber 35r will be described. After that, other configurations of the hydraulic pressure circuit 553 will be described.

(Flow path between the accumulator and the head concubine)
The hydraulic circuit 553 has a flow path 54a that communicates the accumulator 47 and the head side chamber 35h. The flow path 54a contributes to, for example, allowing the hydraulic fluid to flow from the accumulator 47 to the head side chamber 35h to advance the piston 37. Further, the flow path 54a contributes to filling the accumulator 47 by flowing the hydraulic fluid from the head side chamber 35h to the accumulator 47, for example, when the piston 37 retracts.

The hydraulic circuit 553 has, for example, a flow rate control valve 55 and a check valve 59A as valves that are located in the flow path 54a and can allow and prohibit the flow of the hydraulic fluid in the flow path 54a.

The flow rate control valve 55 can control the flow rate of the hydraulic fluid in the flow path 54a. By controlling the flow rate of the hydraulic fluid supplied from the accumulator 47 to the head side chamber 35h, for example, the forward speed of the piston 37 is controlled. That is, the flow control valve 55 constitutes a so-called meter-in circuit.

The flow rate control valve 55 is composed of, for example, a flow rate adjusting valve with pressure compensation that can keep the flow rate constant even if there is a pressure fluctuation. Further, the flow rate control valve 55 is used in a servo mechanism, for example, and is configured by a servo valve capable of steplessly (continuously, to an arbitrary value) modulation of the flow rate according to an input signal.

The flow control valve 55 may have various configurations including known configurations. In the illustrated example, the flow rate control valve 55 has a main valve 56 that controls the flow of the hydraulic fluid in the flow path 54a, and a pilot valve 57 that controls the operation of the main valve 56.

The main valve 56 is located in the flow path 54a and directly controls the flow rate of the hydraulic fluid in the flow path 54a. The main valve 56 is composed of, for example, a 2-port 2-position switching valve in which the flow is continuously switched depending on the position of the valve body. The position of the valve body is controlled by the pilot pressure introduced on both sides of the valve body in the moving direction. Further, the position of the valve body is detected by a sensor (for example, a differential transformer).

The pilot valve 57 controls the pilot pressure introduced on both sides of the valve body of the main valve 56. Specifically, the pilot valve 57 has two ports leading to both sides (two flow paths 54b) of the valve body of the main valve 56, and two leading to the accumulator 47 (flow path 54c) and the tank 51 (flow path 54d). Has a port. The pilot valve 57 is composed of a 4-port 3-position switching valve that continuously switches the connection between the former two ports and the latter two ports depending on the position of the valve body. The position of the valve body is controlled by, for example, an electromagnetic drive unit (for example, a solenoid).

In each of the main valve 56 and the pilot valve 57, the leakage of the hydraulic fluid is collected in the tank 51. The valve body may be urged in place by a spring (as well as the valve bodies of other valves).

The check valve 59A is composed of a check valve that is opened and closed by the introduction of pilot pressure. The check valve 59A allows the flow from the accumulator 47 to the head concubine 35h and prohibits the flow in the opposite direction when the pilot pressure is not applied. Therefore, for example, when the hydraulic fluid in the head side chamber 35h is pressurized by the pressurizing member 541 and the pressure in the head side chamber 35h becomes higher than the pressure in the accumulator 47, the check valve 59A closes by itself.

The introduction of the pilot pressure to the check valve 59A may be made, for example, by a switching valve 60A located between the check valve 59A and the accumulator 47. The switching valve 60A has, for example, two ports, a port for supplying the open pilot pressure to the check valve 59A, a port for supplying the closing pilot pressure to the check valve 59A, and two ports leading to the accumulator 47 and the tank 51. Have. The switching valve 60A is composed of a 4-port 2-position switching valve that switches the connection between the former two ports and the latter two ports depending on the position of the valve body. The position of the valve body is controlled by, for example, an electromagnetic drive unit (for example, a solenoid).

(Flow path between accumulator and rear concubine)
The hydraulic circuit 553 has a flow path 54m that communicates the accumulator 47 and the rear chamber 35a. The flow path 54m contributes to advancing the pressurizing member 541 by flowing the hydraulic fluid from the accumulator 47 to the rear chamber 35a, for example. Further, the flow path 54m contributes to filling the accumulator 47 by flowing the hydraulic fluid from the rear side chamber 35a to the accumulator 47, for example, when the pressurizing member 541 retracts.

The flow path 54m shares a part of the accumulator 47 side with the flow path 54a. However, the flow path 54m may be a flow path separate from the flow path 54a over the entire flow path.

The flow control valve 55 described above may be located in the common area between the flow path 54m and the flow path 54a. That is, the flow rate control valve 55 may be able to control the flow rate of the hydraulic fluid flowing from the accumulator 47 to the rear chamber 35a. However, the flow rate control valve 55 may be arranged at a position not shared with the flow path 54m in the flow path 54a. In this case, the portion of the flow path 54m that is not shared with the flow path 54a may or may not have another flow rate control valve.

The hydraulic circuit 553 has, for example, a flow control valve 55 and a check valve 59E as a valve located in the flow path 54 m and capable of allowing and prohibiting the flow of the hydraulic fluid in the flow path 54 m. The check valve 59E, like the check valve 59A, is composed of a check valve that is opened and closed by the introduction of pilot pressure, for example. The check valve 59E, for example, allows the flow from the accumulator 47 to the rear chamber 35a and prohibits the flow in the opposite direction when the pilot pressure is not applied. The configuration for introducing the pilot pressure into the check valve 59E may be the same as the configuration of the check valve 59A, and is not shown in FIG.

(Flow path between rod concubine and tank)
The hydraulic circuit 553 has a flow path 54e that communicates the rod side chamber 35r and the tank 51. The flow path 54e contributes to, for example, allowing the hydraulic fluid of the rod side chamber 35r to flow to the tank 51 when the piston 37 advances to allow the piston 37 to advance.

The hydraulic circuit 553 has, for example, a check valve 59B as a valve located in the flow path 54e and capable of allowing and prohibiting the flow of the hydraulic fluid in the flow path 54e. The configuration of the check valve 59B is, for example, the same as the configuration of the check valve 59A. The above-mentioned explanation regarding the configuration of the check valve 59A may be incorporated into the configuration of the check valve 59B as long as there is no contradiction or the like. When the pilot pressure is not applied, the check valve 59A allows the flow from the rod side chamber 35r to the tank 51 and prohibits the flow in the opposite direction.

The introduction of the pilot pressure to the check valve 59B may be made, for example, by a switching valve 60B located between the check valve 59B and the accumulator 47. The configuration of the switching valve 60B is, for example, the same as the configuration of the switching valve 60A. The above-mentioned description regarding the configuration of the switching valve 60A may be incorporated into the configuration of the switching valve 60B as long as there is no contradiction or the like.

An accumulator 61 may be connected between the rod side chamber 35r and the tank 51 (more specifically, for example, between the check valve 59B and the tank 51). The accumulator 61 contributes to, for example, absorbing the surge pressure generated in the rod side chamber 35r when the filling of the molten metal is completed. The above-mentioned explanation regarding the configuration of the accumulator 47 may be incorporated into the configuration of the accumulator 61 as long as there is no contradiction or the like. However, since the accumulator 61 is not used as a drive source, it may be smaller than the accumulator 47 and the pressure that can be accumulated may be low.

(Flow path between the pump and the rod concubine)
The hydraulic circuit 553 has a flow path 54f that connects the pump 49 and the rod side chamber 35r. For example, when the piston 37 is retracted by the first drive device 29A, the flow path 54f causes the hydraulic fluid to flow from the pump 49 to the rod side chamber 35r and contributes to supplying the hydraulic fluid to the rod side chamber 35r.

The hydraulic circuit 553 has, for example, a switching valve 62 and a check valve 63A as valves that are located in the flow path 54f and can allow and prohibit the flow of the hydraulic fluid in the flow path 54f. As will be understood from the following description, the combination of these two valves may be regarded as one valve.

The switching valve 62 is located in the flow path 54h for supplying the hydraulic fluid from the pump 49 to the head side chamber 35h, and also functions as a valve that allows and prohibits the flow of the hydraulic fluid in the flow path 54h. The supply of the hydraulic fluid from the pump 49 to the head side chamber 35h is, for example, for compensation and / or maintenance of the leaked hydraulic fluid, as described above.

The switching valve 62 has two ports, a port leading to the rod side chamber 35r and a port leading to the head side chamber 35h, and two ports leading to the pump 49 and the tank 51. The switching valve 62 is composed of a 4-port 3-position switching valve that switches the connection between the former two ports and the latter two ports depending on the position of the valve body. The position of the valve body is controlled by, for example, an electromagnetic drive unit (for example, a solenoid).

More specifically, the three positions of the switching valve 62 are as follows. At the position on the left side of the paper, the rod side chamber 35r and the pump 49 are connected, and the head side chamber 35h and the tank 51 are connected. At the position on the right side of the paper, the rod side chamber 35r and the tank 51 are connected, and the head side chamber 35h and the pump 49 are connected. Neither port is connected at the center of the page. Therefore, for example, by setting the switching valve 62 at the position on the left side of the paper surface, the hydraulic fluid can be supplied from the pump 49 to the rod side chamber 35r.

The check valve 63A is located between the rod side chamber 35r and the switching valve 62. The check valve 63A allows the flow from the switching valve 62 to the rod side chamber 35r, and prohibits the flow in the opposite direction. Thereby, for example, when the switching valve 62 is positioned on the right side of the paper surface in order to supply the hydraulic fluid from the pump 49 to the head side chamber 35h, the hydraulic fluid of the rod side chamber 35r is sent to the tank 51 via the switching valve 62. Flow is prohibited.

Although not particularly shown, the switching valve may not be shared between the flow path 54f and the flow path 54h. For example, a switching valve at 3 ports and 3 positions may be provided in each flow path to allow or prohibit the flow of the hydraulic fluid, or a pilot type check valve may be provided.

(Other configurations of hydraulic circuit)
As described above, the hydraulic circuit 553 has a flow path 54h for supplying the hydraulic fluid from the pump 49 to the head side chamber 35h. The hydraulic circuit 553 has, for example, the above-mentioned switching valve 62 and the check valve 64 as valves that are located in the flow path 54h and can allow and prohibit the flow of the hydraulic fluid in the flow path 54h.

The check valve 64 is located between the head side chamber 35h and the switching valve 62. The check valve 64 allows the flow from the switching valve 62 to the head concubine 35h and prohibits the flow in the opposite direction. As a result, for example, when the switching valve 62 is positioned on the left side of the paper surface in order to supply the hydraulic fluid from the pump 49 to the rod side chamber 35r, the hydraulic fluid in the head side chamber 35h flows to the tank 51 via the switching valve 62. Flow is prohibited. In the illustrated example, the check valve 64 is a pilot-type check valve that is closed (prohibits bidirectional flow) by the introduction of pilot pressure.

The introduction of the pilot pressure of the check valve 64 may be made, for example, by the shuttle valve 65. The shuttle valve 65 has two inlets and one outlet. One of the two inlets is connected to the head concubine 35h side of the check valve 64 of the flow path 54h. The rest of the two inlets are connected to the accumulator 47 via a switching valve 66, which will be described later. The exit leads to the check valve 64. Then, the outlet is connected to the high pressure side of the two inlets, and the pressure from the connected inlet is applied to the check valve 64 as the pilot pressure. This reduces, for example, the probability that the check valve 64 will be opened when it is not intended to be opened.

The flow of hydraulic fluid from the accumulator 47 to the shuttle valve 65 may be controlled, for example, by a switching valve 66 located between the two. The switching valve 66 has, for example, three ports, a port connected to the shuttle valve 65, a port connected to the accumulator 47, and a port connected to the tank 51. The switching valve 66 connects the port leading to the shuttle valve 65 and any one of the other two ports depending on the position of the valve body. The position of the valve body is controlled by, for example, an electromagnetic drive unit (for example, a solenoid).

The hydraulic circuit 553 has, for example, a flow path 54k for supplying the hydraulic fluid from the pump 49 to the accumulator 47. As described above, the accumulator 47 is basically filled by retracting the piston 37 by the first drive device 29A and pushing the hydraulic fluid in the head concubine 35h to the accumulator 47. The supply of hydraulic fluid from the pump 49 to the accumulator 47 is, for example, in compensation for leaked hydraulic fluid and / or maintenance.

The hydraulic circuit 553 has, for example, a switching valve 46 as a valve located in the flow path 54k and capable of allowing and prohibiting the flow of the hydraulic fluid in the flow path 54k. The switching valve 46 connects the accumulator 47 to the pump 49 or the tank 51, or disconnects any of them, depending on the position of the valve body, for example. The position of the valve body is controlled, for example, by sequentially operating the electromagnetic drive unit and the pilot drive unit (see the operation method of the flow control valve 55). The pilot pressure may be, for example, the pressure from the accumulator 47.

In an embodiment in which the front chamber 35f is filled with the hydraulic fluid, the hydraulic circuit 553 may have a flow path connecting the front chamber 35f and the tank 51 (pump 49 if necessary), although not particularly shown. The flow path may be provided with a valve that allows and prohibits the flow of hydraulic fluid.

The hydraulic circuit 553 may have check valves 63B, 63C and 63D at appropriate positions that allow the flow of hydraulic fluid from the pump 49 and prohibit the flow in the opposite direction. Further, the hydraulic pressure circuit 553 may have a check valve (reference numeral omitted) that allows the flow of the hydraulic fluid from the switching valve 66 to the tank 51 and prohibits the flow in the opposite direction. Further, the hydraulic pressure circuit may have a cock 58 at an appropriate position. The cock 58 is, for example, for maintenance and is closed when the injection is taking place. Various instruments (reference numerals omitted) such as a pressure gauge may be connected to the end of the flow path extending from the cock 58. Further, the hydraulic circuit 553 may have a filter 48 and a relief valve 52 at appropriate positions.

(1st drive device)
As described above, the first drive device 29A shown in FIG. 3 has a first electric motor 31A and a detachable portion 33 capable of connecting to and disconnecting from the piston rod 39. The first drive device 29A has, as a component for transmitting the driving force of the first electric motor 31A to the piston rod 39, for example, the first transmission mechanism 67A and the first conversion mechanism 68A in order from the first electric motor 31A to the attachment / detachment portion 33. And has a movable member 69.

The first electric motor 31A is a rotary electric motor. Although not particularly shown, the first electric machine 31A has a stator that constitutes one of the armature or the field, and a rotor that constitutes the other of the armature or the field, as is known. The rotor rotates about an axis with respect to the stator. The specific configuration of the first electric motor 31A may be appropriate. For example, the first electric motor 31A may be a DC motor or an AC motor, may be an induction motor or a synchronous motor, and may or may not have a brake. The first electric motor 31A is configured as, for example, a servomotor, and constitutes a servo mechanism together with a sensor (not shown) that detects the rotation of the first electric motor 31A and a servo driver (not shown) that supplies power to the first electric motor 31A. are doing.

The main body (stator) of the first electric motor 31A is fixed to an immovable portion (for example, a cylinder member 535) of the injection device 509, and various parallel movements and rotational movements are restricted. The arrangement position and orientation of the first electric motor 31A may be appropriately set. In the illustrated example, the first motor 31A is located laterally to the injection cylinder 527 and is fixed to the rear surface of the plate 45c of the frame 45. Further, the first electric motor 31A is arranged so that the output shaft is parallel to the injection cylinder 527 and faces forward.

The first transmission mechanism 67A transmits the rotation of the first electric motor 31A, and contributes to, for example, an improvement in the degree of freedom in the arrangement of the first electric motor 31A and / or a shift in rotation. The first transmission mechanism 67A is composed of, for example, a pulley / belt mechanism, and has a first pulley 70A fixed to the output shaft of the first electric motor 31A and a first nut 71A (which is also used for the first conversion mechanism 68A). It has a pulley) and a first belt 72A suspended on the first pulley 70A and the first nut 71A. Therefore, when the first electric motor 31A is rotated, the rotation is transmitted to the first conversion mechanism 68A via the first transmission mechanism 67A. The diameter of the first pulley 70A and the diameter of the first nut 71A may be larger or the same. In the illustrated example, the diameter of the first nut 71A is larger than the diameter of the first pulley 70A, and the rotation of the first electric motor 31A is decelerated.

The specific arrangement position of the first transmission mechanism 67A may be appropriately set. In the illustrated example, the first transmission mechanism 67A is located laterally to the injection cylinder 527 and is also located within the plate 45c of the frame 45. The first pulley 70A and the first nut 71A are aligned in the lateral direction of the injection cylinder 527.

The first conversion mechanism 68A contributes to converting the rotational motion of the first electric motor 31A into a linear motion (translational motion). The first conversion mechanism 68A is configured by, for example, a screw mechanism (for example, a ball screw mechanism or a sliding screw mechanism). The first conversion mechanism 68A has a first screw shaft 73A and a first nut 71A that is screwed directly to the first screw shaft 73A via a ball (not shown). One member of the first screw shaft 73A and the first nut 71A (the first nut 71A in the illustrated example) is allowed to rotate around the axis and is restricted from moving in the axial direction, for example. The other member (first screw shaft 73A in the illustrated example) is, for example, restricted in rotation around the axis and allowed to move in the axial direction. Therefore, by rotating one member (first nut 71A), the other member (first screw shaft 73A) is driven in the axial direction. The specific configuration of the first conversion mechanism 68A may be appropriately set. For example, the thread groove (not shown) may be provided with one thread or two or more threads. Further, for example, the diameter and lead of the first screw shaft 73A are arbitrary.

The first conversion mechanism 68A is arranged in parallel with the injection cylinder 527. That is, the first screw shaft 73A is parallel to the piston rod 39, and the direction of the linear motion of the first conversion mechanism 68A is parallel to the drive direction (front-back direction) of the injection cylinder 527. The specific arrangement position of the first conversion mechanism 68A, the method of restricting the parallel movement of the first nut 71A, the method of restricting the rotation of the first screw shaft 73A, and the like may be appropriately set. In the illustrated example, the first conversion mechanism 68A is located on the side of the injection cylinder 527 and is located on the injection cylinder 527 side of the first electric motor 31A. Further, the first nut 71A is arranged inside the plate 45c of the frame 45, and is supported by the plate 45c in a state where only rotation is permitted by a bearing (not shown). The rotation of the first screw shaft 73A is restricted by being connected to a movable member 69 that is allowed only to be translated in the front-rear direction.

The movable member 69 is a member that is driven in the front-rear direction by the driving force of the first electric motor 31A, contributes to transmitting the driving force of the first electric motor 31A to the plunger 21, and also contributes to the support of the detachable portion 33. There is. The movable member 69 may be regarded as a part of the detachable portion 33. The shape, dimensions and material of the movable member 69 are arbitrary. In the illustrated example, the movable member 69 is a member shared by the two first drive devices 29A (see also FIG. 2), and extends in the lateral direction of the injection cylinder 527 (vertical direction on the paper surface in FIG. 3). , The shape has a hole through which the piston rod 39 is inserted. Further, the movable member 69 is generally in the shape of a plate facing in the front-rear direction.

The first drive device 29A may have a guide mechanism for guiding the movable member 69 in the front-rear direction (in another viewpoint, restricting movements other than translation in the front-rear direction). In the examples of FIGS. 2 and 3, a pair of guide shafts 74 is exemplified as the guide mechanism. A pair of guide shafts 74 extend in the front-rear direction and are fixed to the frame 45. The movable member 69 is allowed to move only in the front-rear direction by inserting a pair of guide shafts 74. Further, in FIG. 1, a linear guide 75 that supports and guides the movable member 69 from below is exemplified.

The detachable portion 33 shown in FIG. 3 is supported by the movable member 69 and moves in the front-rear direction together with the movable member 69. The attachment / detachment portion 33 connects and disconnects the movable member 69 and the predetermined portion (attached / detached portion 39z) of the piston rod 39. The attached / detached portion 39z is located outside the cylinder member 535 regardless of the position of the piston 37, for example. That is, even when the piston 37 is positioned at the retreat limit due to abutting rearward against a stopper (not shown) in the cylinder member 535, the detached portion 39z is located outside the cylinder member 535.

By connecting the movable member 69 and the detachable portion 39z, for example, the plunger 21 can be retracted by the driving force of the first electric motor 31A. Further, by disconnecting the movable member 69 and the piston rod 39, for example, when the hydraulic fluid is supplied to the head side chamber 35h and the plunger 21 is advanced at high speed, it is caused by the inertial force of the first drive device 29A. The slowdown of the plunger 21 is avoided.

The attachment / detachment portion 33 has, for example, an engagement member 76 that can be engaged with the attachment / detachment portion 39z of the piston rod 39, and an actuator 77 that drives the engagement member 76. The engaging member 76 is movably supported by the movable member 69 between an engaging position that engages with the detached portion 39z in the front-rear direction and a disengaging position (position in FIG. 3) where the engagement is released. Has been done. The actuator 77 moves the engaging member 76 between the engaging position and the disengaging position.

The specific shapes of the engaging member 76 and the attached / detached portion 39z may be appropriately set. In the illustrated example, the attached / detached portion 39z has a small diameter portion 39a, a first large diameter portion 39b, and a second large diameter portion 39c. The first large diameter portion 39b is located behind the small diameter portion 39a and has a larger diameter than the small diameter portion 39a. The second large diameter portion 39c is located in front of the small diameter portion 39a and has a larger diameter than the small diameter portion 39a. The engaging member 76 is inserted between the first large diameter portion 39b and the second large diameter portion 39c to engage the engaging member 76 rearwardly or anteriorly with respect to the first large diameter portion 39b and the second large diameter portion 39c. Further, the engaging member 76 is disengaged by retracting from between the first large diameter portion 39b and the second large diameter portion 39c.

In the illustrated example, the diameters of the first large diameter portion 39b and the second large diameter portion 39c are the same as the diameters of most of the piston rod 39. That is, the small diameter portion 39a is formed by reducing the diameter of a part of the piston rod 39. However, for example, the diameter of the small diameter portion 39a may be the same as the diameter of most of the piston rod 39. The first large diameter portion 39b and the second large diameter portion 39c may be configured by a flange. The first large diameter portion 39b and the second large diameter portion 39c may have different diameters from each other, unlike the illustrated example.

The configuration of the actuator 77 may be appropriate. In the illustrated example, the actuator 77 is not particularly designated, but is a combination of a spring and a pneumatic cylinder. Specifically, the actuator 77 has a cylinder chamber formed in the movable member 69, a piston slidable in the cylinder chamber, and a piston rod extending from the piston and connected to the engaging member 76. Have. The spring, for example, urges the piston in a direction in which the engaging member 76 is disengaged. By supplying gas (for example, air) to the side of the piston opposite to the piston rod, the engaging member 76 moves from the disengaging position to the engaging position. Other examples of the actuator 77 include, for example, a linear motor or a hydraulic cylinder.

The arrangement position of the first drive device 29A may be appropriately set. In the illustrated example, the two first drive devices 29A are arranged line-symmetrically with respect to the injection cylinder 527 in top view. Further, the two first drive devices 29A are located at the same height as the injection cylinder 527 in the vertical direction, for example. More specifically, for example, the axes of the two first screw shafts 73A and the piston rod 39 may be located at the same height in the vertical direction.

As described above, the first drive device 29A retracts the plunger 21 after the injection is completed. Therefore, the first drive device 29A is configured to be able to move the attachment / detachment portion 33 with a stroke equal to or greater than the stroke intended for the plunger 21. The stroke of the first drive device 29A and the stroke of the injection cylinder 527 may be the same, or one of them may be larger than the other.

(Example of the shape of the engaging member)
5 (a) and 5 (b) are views showing an example of the shape of the engaging member 76 of the attachment / detachment portion 33. These figures correspond to the VV lines of FIG. FIG. 5A shows a state in which the engaging member 76 is not engaged with the piston rod 39. FIG. 5B shows a state in which the engaging member 76 is engaged with the piston rod 39.

As described above, the engaging member 76 is inserted between the first large diameter portion 39b and the second large diameter portion 39c, and is front and rear with respect to the first large diameter portion 39b and the second large diameter portion 39c. Engage in direction. From another viewpoint, the engaging member 76 moves to an engaging position that faces the outer peripheral surface of the small diameter portion 39a and can be rearwardly engaged with the first large diameter portion 39b. Further, the engaging member 76 is retracted from between the first large diameter portion 39b and the second large diameter portion 39c, and the engagement with the first large diameter portion 39b and the second large diameter portion 39c is released. From another viewpoint, the engaging member 76 moves to a position outside the engaging position in the radial direction of the small diameter portion 39a and not engaging with the first large diameter portion 39b.

As described above, the engaging member 76 has a portion facing the outer peripheral surface of the small diameter portion 39a. The portion may have a recess 76a that accommodates a portion of the small diameter portion 39a around the axis at the engaging position when viewed in the axial direction of the piston rod 39. By providing such a recess 76a, for example, the amount at which the engaging member 76 and the first large diameter portion 39b (second large diameter portion 39c) engage with each other with respect to the angular range around the axis of the small diameter portion 39a is increased. Can be made larger.

The specific shape of the recess 76a (and the piston rod 39) may be appropriately set. In the illustrated example, the small diameter portion 39a and the first large diameter portion 39b (the second large diameter portion 39c may be the same as the first large diameter portion 39b) each have a circular cross-sectional shape. The recess 76a of one engaging member 76 has a semicircular shape having a diameter equal to or larger than the diameter of the small diameter portion 39a and smaller than the diameter of the first large diameter portion 39b. More specifically, for example, the diameter of the recess 76a is substantially the same as the diameter of the small diameter portion 39a. Then, the two engaging members 76 engage with the first large diameter portion 39b over the entire circumference around the small diameter portion 39a.

(Other configurations of die casting machine)
The die casting machine 501 may have various sensors so that the control device 5 can control the operation of the machine body 503. Then, the control device 5 may control the hydraulic pressure device 543, the first electric motor 31A, and the attachment / detachment unit 33 (actuator 77) based on the detection values of various sensors.

An example of the sensor as described above is given. For example, a position sensor 99 (FIG. 3) that detects the position of the piston rod 39 (plunger 21), a pressure sensor (not shown) that detects the pressure of the accumulator 47, and a pressure sensor 97H (FIG. 4) that detects the pressure of the head side chamber 35h. ), Pressure sensor 97R that detects the pressure of the rod side chamber 35r, Sensor that detects the position of the movable member 69 (not shown), Sensor that detects the rotation speed (rotation speed) of the first electric motor 31A (not shown), Pressurization A sensor (not shown) for detecting the position of the member 541 and / or a sensor (not shown) for detecting the pressure of the first electric motor 31A may be provided.

Since the velocity (or rotation speed) is obtained by differentiating the position (or rotation position), the position sensor may be regarded as a velocity sensor. Similarly, the sensor that detects the rotation speed may be regarded as the sensor that detects the rotation position. The various sensors may be of various types, including known configurations. For example, the sensor that detects the positions of the piston rod 39, the movable member 69, and the pressurizing member 541 may be a linear encoder or a laser length measuring instrument. The sensor that detects rotation may be an encoder or resolver. The sensor that detects the torque may utilize a strain gauge. Further, a current detector that detects the current flowing through the motor may also be regarded as a torque sensor.

(Operation of injection device)
FIG. 6 is a diagram illustrating the operation of the injection device 509.

In FIG. 6, the horizontal axis represents time t. Further, the solid line Lv indicates the change in the injection speed (the speed of the plunger 21), and the broken line Lp indicates the change in the injection pressure (for example, the pressure applied to the molten metal by the plunger 21). In the graph in which the solid line Lv and the broken line Lp are drawn, the vertical axis indicates the magnitudes of the injection speed V and the injection pressure P.

In the lower part of FIG. 6, the operations of the accumulator 47 (abbreviated as “ACC”), the first electric motor 31A, and the attachment / detachment portion 33 are shown. In "ACC", "release" indicates a state in which the hydraulic fluid is discharged from the accumulator 47 to the head side chamber 35h and / or the rear side chamber 35a, and "filling" means that the hydraulic fluid in the head side chamber 35h or the rear side chamber 35a is the accumulator. 47 indicates a state of being filled, and "stop" indicates a state in which the flow of any of the above hydraulic fluids is prohibited. In the "first electric motor" and the "second electric motor", "forward rotation" indicates a state in which the attachment / detachment portion 33 or the pressurizing member 541 is rotated in the forward direction, and "reverse rotation" indicates the opposite direction. "Stop" indicates a state in which rotation is performed, and "stop" indicates a state in which rotation is not performed. In "detachment", "ON" indicates a state in which the attachment / detachment portion 33 is connected to the piston rod 39, and "OFF" indicates a state in which the connection is released. The stop of the motor may be, for example, a torque-free state, a state in which position control is performed, or a state in which the brake is operating.

In "ACC", "first electric motor" and "detachment", the broken line indicates the operation of the modification described later. See the solid line here.

For example, the injection device 509 performs low-speed injection (time points t0 to t1), high-speed injection (time points t1 to t3), pressure increase (time points t4 to t6), and pressure holding (time points t6 to t7) in order. That is, in the initial stage of injection, the injection device 509 performs low-speed injection in which the plunger 21 is advanced at a relatively low speed (speed _VL ) from the viewpoint of preventing air from being entrained in the molten metal. Next, the injection device 509 performs high-speed injection in which the plunger 21 is advanced at a relatively high speed (speed _VH ) from the viewpoint of filling the molten metal without delaying the solidification of the molten metal. Next, the injection device 509 increases the molten metal in the cavity 107 to the casting pressure _PE by the force in the forward direction of the plunger 21 from the viewpoint of eliminating sink marks on the molded product. After that, the injection device 509 holds the casting pressure _PE .

The low-speed injection and the high-speed injection are performed by supplying the hydraulic fluid from the accumulator 47 to the head side chamber 35h (see “Discharge” of ACC in the figure). In the initial stage, the pressure increase is performed by supplying the hydraulic fluid from the accumulator 47 to the head concubine 35h. The rest of the step of increasing the pressure and the holding pressure are performed by supplying the hydraulic fluid (pressure is applied) from the accumulator 47 to the rear chamber 35a. After that, the plunger 21 is retracted by the driving force of the first motor 31A (see "reversal" of the first motor in the figure). At this time, the accumulator 47 is filled by pushing out the hydraulic fluid from the head side chamber 35h (see “Filling” of ACC in the figure). Specifically, it is as follows.

(Low speed injection: t0 to t1)
Immediately before the start of low-speed injection, the injection device 509 is in the state shown in FIGS. 1 to 3. That is, the piston 37 and the pressurizing member 541 are located at the initial positions such as the retreat limit. The attachment / detachment portion 33 is disconnected (engaged). Various valves of the hydraulic circuit 553 are controlled so as to basically prohibit the flow of the hydraulic fluid, for example. The first electric motor 31A and the pump 49 (the electric motor that drives the pump 49) are stopped.

The control device 5 determines whether or not the predetermined injection start condition is satisfied. The injection start condition may be, for example, that the molding of the fixed mold 103 and the moving mold 105 is completed, and information indicating that the molten metal has been supplied to the sleeve 19 has been obtained. Then, when the control device 5 determines that the injection start condition is satisfied, the control device 5 starts injection (low-speed injection).

Specifically, the control device 5 opens the flow rate control valve 55 and the check valve 59A. As a result, the hydraulic fluid is supplied from the accumulator 47 to the head side chamber 35h. Further, the control device 5 opens the check valve 59B. As a result, the hydraulic fluid is allowed to be discharged from the rod side chamber 35r. Then, the piston 37 advances while discharging the hydraulic fluid of the rod side chamber 35r by the pressure received from the head side chamber 35h. As a result, the piston rod 39 and the plunger 21 move forward.

The speed of the plunger 21 is controlled by adjusting the flow rate of the hydraulic fluid supplied to the head side chamber 35h by the flow rate control valve 55. Specifically, the control device 5 feedback-controls the opening degree of the flow rate control valve 55 so that the speed of the plunger 21 detected by the position sensor 99 converges to the target speed. This feedback control may be, for example, the feedback control of the speed itself, or the substantial speed realized by the feedback control of the position performed so that the position of the detected plunger 21 becomes the target position every moment. It may be feedback control of. The speed of the plunger 21 is, for example, low (for example, less than 1 m / s) and constant. However, multi-stage control of the speed of the plunger 21 may be performed.

When low-speed injection is being performed, the control device 5 disconnects the attachment / detachment portion 33 from the piston rod 39. Therefore, the speed of the piston rod 39 is not affected by the driving state of the first electric motor 31A. In the illustrated example, the first motor 31A is stopped at the start of injection. Therefore, the piston rod 39 (attached / detached portion 39z) moves forward leaving the detachable portion 33 (movable member 69) behind.

(Advance of detachable part)
The control device 5 starts the normal rotation of the first electric motor 31A at an appropriate time, and advances the attachment / detachment portion 33. The start time of the normal rotation and the speed of the normal rotation may be appropriately set. However, in the illustrated example, the attachment / detachment portion 33 is set to the plunger 21 by the time when the attachment / detachment portion 33 needs to be engaged with the plunger 21 (time point t11 in the illustrated example) for the start time of the forward rotation and the speed of the forward rotation. It is set to reach a position (small diameter portion 39a) that can be connected to.

Examples of the start time of normal rotation and the speed of normal rotation of the first electric motor 31A will be given. The start time of normal rotation may be before the start of injection (before time point t0), at the start of injection (time point t0), during low-speed injection (example in the figure), during high-speed injection, or after high-speed injection. Further, the speed of the attachment / detachment portion 33 driven by the normal rotation of the first electric motor 31A is lower than the high-speed injection speed _VH . Further, the speed may be lower, equal to, or higher than the low speed injection speed _VL .

As can be understood from the various examples of the start time and the speed described above, unlike the above description, the attachment / detachment portion 33 may temporarily or always precede the attachment / detachment portion 39z of the piston rod 39. I do not care.

(High-speed injection: t1 to t3)
When the predetermined high-speed start condition is satisfied, the control device 5 increases the opening degree of the flow rate control valve 55, increases the flow rate of the hydraulic fluid from the accumulator 47 to the head side chamber 35h, and increases the speed of the plunger 21. The control at this time may be the same as the control at the time of low-speed injection, except that the target speed is different, for example. The high-speed start condition may be, for example, that the position of the plunger 21 has reached a predetermined high-speed switching position. For example, the control device 5 may determine whether or not the detection position of the plunger 21 has reached the high-speed switching position and switch the target speed, or the control device 5 may switch the target speed every moment set based on the high-speed switching position and the target speed. It may only achieve the target position.

(Advance of pressure member)
The control device 5 opens the check valve 59E at an appropriate time before the start time of the pressure increase by the pressurizing member 541 (time point t5 in the illustrated example) to allow the flow of the hydraulic fluid from the accumulator 47 to the rear chamber 35a. Allow and advance the pressurizing member 541. By advancing the pressurizing member 541 in advance in this way, for example, the transition to the pressure increase by the pressurizing member 541 is smoothly performed. On the other hand, since the speed of the pressurizing member 541 is controlled by the flow control valve 55 together with the speed of the piston 37, the speed control by the meter-in circuit is maintained.

To give an example of the time when the pressurizing member 541 starts advancing, the time is during low-speed injection, during speed increase (time points t1 to t2), and during high-speed injection after speed increase is completed (time points t2-t3, shown in the figure). Example) or during deceleration injection (after time point t3 and before time point t4). However, unlike the above description, pressurization is performed at the time when the flow of the hydraulic fluid from the accumulator 47 to the head concubine 35h is prohibited (time point t5; from another viewpoint, the time when the pressure increase switching condition described later is satisfied). The advancement of the member 541 (from another viewpoint, the supply of the hydraulic fluid from the accumulator 47 to the rear chamber 35a) may be started.

(Deceleration injection: t3 to t4)
When the molten metal is filled in the cavity 107 to some extent, the plunger 21 receives a reaction force from the filled molten metal and is decelerated, while the injection pressure rises sharply. The operation of each part is the same as that at the time of high-speed injection. However, deceleration control may be performed to reduce the opening degree of the flow rate control valve 55. By such deceleration control, for example, the impact at the time of filling is alleviated.

(Pressure increase by supplying hydraulic fluid to the head concubine: t4 to t5)
The control device 5 controls the hydraulic pressure circuit 553 so as to start the pressure increase when a predetermined pressure increase start condition is satisfied. The pressure increase start condition is, for example, that the injection pressure based on the detection value of the pressure sensor 97H (and the pressure sensor 97R that detects the pressure of the rod side chamber 35r if necessary) that detects the pressure of the head side chamber 35h reaches a predetermined pressure. That is, or the detection position of the plunger 21 detected by the position sensor 99 has reached a predetermined position.

The control device 5 performs speed control based on the detection value (detection value of the injection speed) of the position sensor 99 from the low speed injection to the deceleration injection. On the other hand, when the pressure increase is started, the control device 5 performs pressure control based on the detection value (detection value of injection pressure) of the pressure sensor 97H (and, if necessary, the pressure sensor 97R). In the pressure control, the control device 5 feedback-controls the flow rate control valve 55 so that the detected value of the injection pressure rises along a predetermined step-up curve, for example.

(Pressure increase by supplying hydraulic fluid to the rear concubine: t5 to t6)
The control device 5 closes the check valve 59A when a predetermined pressure increase switching condition is satisfied. As a result, the backflow of the hydraulic fluid from the head side chamber 35h to the accumulator 47 is prohibited. However, the check valve 59A may be self-closed by the pressure of the hydraulic fluid in the head side chamber 35h. Specifically, when the piston 37 is advancing, the volume of the head side chamber 35h is expanded, the pressure of the head side chamber 35h is lower than the pressure of the accumulator 47, and the check valve 59A does not self-close. After that, when the molding material is substantially filled in the cavity 107 and the expansion of the volume of the head side chamber 35h is substantially stopped, the pressure of the head side chamber 35h becomes higher than the pressure of the accumulator 47 due to the pressure increasing action of the pressurizing member 541. As a result, the check valve 59A closes by itself. The control device 5 controls the flow rate control valve 55 so as to apply pressure to the hydraulic fluid in the head side chamber 35h by the pressurizing member 541 to continue the pressure increase.

The pressure increase switching condition is, for example, that the injection pressure based on the detection value of the pressure sensor 97H (and the pressure sensor 97R that detects the pressure of the rod side chamber 35r if necessary) that detects the pressure of the head side chamber 35h reaches a predetermined pressure. It may be considered that the detection position of the plunger 21 detected by the position sensor 99 has reached a predetermined position. That is, the conditions may be the same as the pressure increase start condition, and the specific pressure or position as a determination criterion may be different from the pressure increase start condition.

In the above, the pressure increase start condition and the pressure increase switching condition are set by supplying the hydraulic fluid from the accumulator 47 to the head side chamber 35h to perform a part of the initial stage of the pressure increase step. However, the entire pressure increasing step is performed only by supplying the hydraulic fluid from the accumulator 47 to the rear side chamber 35a (when the hydraulic fluid is being supplied from the accumulator 47 to the head side chamber 35h, the pressure control based on the pressure sensor is not performed. ), And the pressure increase start condition and the pressure increase switching condition may be integrated.

The control when the hydraulic fluid is supplied from the accumulator 47 to the rear side chamber 35a to increase the pressure is, for example, the hydraulic fluid is supplied from the accumulator 47 to the head side chamber 35h except that the check valve 59A is closed. It is the same as the control when increasing the pressure. As is clear from the fact that the check valve 59A may be closed by itself, the control for increasing the pressure may be the same before and after the check valve 59A is closed. In this case, the pressure increase switching condition is not set, and only the pressure increase start condition may be set. The control device 5 feedback-controls the flow rate control valve 55 so that the detected value of the injection pressure rises along a predetermined step-up curve, for example. As a result, the injection pressure reaches the casting pressure _PE (final pressure).

(Holding pressure: t6 to t7)
When the control device 5 determines that the injection pressure has reached the final pressure based on the detection value of the pressure sensor or the like, the control device 5 controls the hydraulic pressure device 543 so that the final pressure is maintained. That is, holding pressure is performed. Specifically, for example, pressure retention is performed by continuing to apply pressure from the accumulator 47 to the rear concubine 35a.

During the holding pressure, the molten metal in the cavity 107 is cooled and solidified. When the control device 5 determines that the molten metal has solidified (time point t7), the control device 5 controls the hydraulic pressure device 543 so as to end the holding pressure. For example, the control device 5 closes the flow control valve 55 and the check valve 59E, and prohibits the flow of the hydraulic fluid from the accumulator 47 to the rear chamber 35a. The control device 5 may appropriately determine whether or not the molten metal has solidified. For example, the control device 5 determines whether or not the molten metal has solidified depending on whether or not a predetermined time has elapsed from a predetermined time point such as t6 when the final pressure is obtained.

(Arrival of detachable part)
The speed of the plunger 21 is reduced by the deceleration injection and the pressure increase, and further, the holding pressure is started and the plunger 21 is stopped. Therefore, the detachable portion 33 driven by the first electric motor 31A catches up with the attached / detached portion 39z of the piston rod 39. In other words, the detachable portion 33 may be in a state of being connectable to the attached / detached portion 39z.

The control device 5 determines that the detachable portion 33 has reached a predetermined stop position based on the detection value of the sensor that detects the position of the detachable portion 33 (movable member 69) or the sensor that detects the rotation of the first electric motor 31A. When it is detected, the first electric motor 31A is stopped. The above stop position is, for example, the position of the detachable portion 33 (the position where it can be connected to the detachable portion 33) when the detachable portion 33 is connected to the attached / detached portion 39z (time point t11 in the illustrated example), or a position in the vicinity thereof. Is.

As described above, the time when the detachable portion 33 reaches the stop position is set before the time when the connection is required (time point t11 in the illustrated example) in the illustrated example. The specific time may be an appropriate time. For example, the time may be during deceleration injection, pressure increase, pressure retention (example in the figure), or after the pressure retention is completed (but before connection).

(Protruding operation: t9 to t10)
After the holding pressure is completed, the control device 5 controls the mold clamping device 7 so as to move the moving mold 105 away from the fixed mold 103 to open the mold. The molded product formed by solidifying the molten metal separates from one of the fixed mold 103 and the moving mold 105 and remains in the other mold. After that (or at the same time as the mold opening), the control device 5 controls the extrusion device (not shown) so as to extrude the molded product from the other mold.

A control device when the molded product is separated from the fixed mold 103 as the other mold by opening the mold by the mold clamping device 7, or when the molded product is extruded from the fixed mold 103 as the other mold by the extruder. 5 may control the injection device 509 so as to perform an operation of pushing out the molded product from the fixed mold 103 (hereinafter, may be referred to as “protruding operation”) by the plunger 21.

Specifically, for example, the control device 5 opens the flow rate control valve 55 and the check valve 59E, and pressurizes the hydraulic fluid in the head side chamber 35h by the pressurizing member 541. The control at this time may be speed control or torque control. For example, the control device 5 controls the speed based on the detected speed of the plunger 21 so that the speed of the plunger 21 becomes the same as the speed of the moving mold 105 or the speed of the extrusion pin of the extruder (not shown). You may go.

(Plunger retreat: t11 ~)
As described above, the detachable portion 33 is stopped at a position (or in the vicinity thereof) of the piston rod 39 which can be connected to the attached / detached portion 39z. When the projecting operation is completed, the control device 5 connects the attachment / detachment portion 33 to the attachment / detachment portion 39z. At this time, one of the positions may be finely adjusted so that the detachable portion 33 and the attached / detached portion 39z are in removable relative positions. After that, the control device 5 reverses the first electric motor 31A and retracts the piston 37.

When reversing the first motor 31A, the control device 5 opens, for example, the flow rate control valve 55 and the check valve 59E. As a result, the pressurizing member 541 retracts as the piston 37 retracts, and the hydraulic fluid discharged from the rear concubine 35a is filled in the accumulator 47. At this time, the check valve 59A may be closed by the pilot pressure or may be self-closed.

Next, the control device 5 closes the check valve 59E and opens the check valve 59A. As a result, the accumulator 47 is filled with the hydraulic fluid discharged from the head side chamber 35h as the piston 37 retracts. The timing of closing the check valve 59E and opening the check valve 59A may be, for example, a time when the pressurizing member 541 is located at the retreat limit, or a time when a predetermined margin time has elapsed from the time. Whether or not the pressurizing member 541 is located in the retracting limit may be determined based on, for example, a sensor (not shown) that detects the position of the pressurizing member 541.

While the piston 37 is retracted as described above, the control device 5 closes the check valve 59B to prohibit the flow of the hydraulic fluid from the rod side chamber 35r to the tank 51, and operates from the pump 49 to the rod side chamber 35r. The switching valve 62 is switched to a position where the flow of liquid is allowed, and the pump 49 is driven. As a result, the hydraulic fluid is supplied from the pump 49 to the rod side chamber 35r.

Note that, unlike the illustrated example, the detachable portion 33 may be connected to the attached / detached portion 39z after the attached / detached portion 33 catches up with the attached / detached portion 39z and before the time when the need for connection arises. I do not care. For example, the detachable portion 33 may be connected to the attached / detached portion 39z during or after the holding pressure is completed (however, before the time when the need for connection arises).

The piston 37 and the pressurizing member 541 are retracted as described above, and then the various valves are closed, so that the injection device 509 returns to the initial position shown in FIGS. 1 and 2. That is, the next molding cycle (injection cycle) is ready.

As described above, in the present embodiment, the injection device 509 includes an injection cylinder 27, a hydraulic pressure device 543, a first drive device 29A, and a control device 5. The injection cylinder 27 is connected to the rear end of the plunger 21 that advances in the sleeve 19 extending in the front-rear direction and pushes the molding material into the inside (cavity 107) of the mold (mold 101). The hydraulic pressure device 543 supplies the hydraulic fluid to the injection cylinder 27. The first drive device 29A is connected to and disconnected from the injection cylinder 27. The control device 5 controls the hydraulic pressure device 543 and the first drive device 29A.

More specifically, the injection cylinder 27 has a piston rod 39, a piston 37, and a cylinder member 535. The piston rod 39 is connected to the rear end of the plunger 21. The piston 37 is connected to the rear end of the piston rod 39. The cylinder member 35 has a space for slidably accommodating the piston 37 in the front-rear direction. The space is divided by a piston 37 into a rod side chamber 35r where the piston rod 39 is located and a head side chamber 35h on the opposite side thereof.

The hydraulic pressure device 43 has a first accumulator (accumulator 47) and a hydraulic pressure circuit 53. The accumulator 47 supplies the hydraulic fluid to the head side chamber 35h. The hydraulic circuit 53 controls the flow of the hydraulic fluid between the accumulator 47 and the head side chamber 35h.

The first drive device 29A has a first electric motor 31A, a movable member 69, and a detachable portion 33. The movable member 69 is driven in the front-rear direction by the first electric motor 31A. The attachment / detachment portion 33 allows and prohibits the movable member 69 from retracting with respect to the piston rod 39.

The control device 55 starts advancing the piston 37 and ejects the movable member 69 by supplying the hydraulic fluid from the accumulator 47 to the head concubine 35h in a state where the movable member 69 is allowed to retreat from the piston rod 39 by the detachable portion 33. Is configured to perform control (time point t0) to start. Further, in the control device 5, the movable member 69 is retracted by the first electric motor 31A in a state where the movable member 69 is prohibited from retracting with respect to the piston rod 39 by the detachable portion 33, and the piston 37 retracting the movable member 69 causes the head side chamber 35h. It is configured to control the hydraulic fluid to be pushed out to the accumulator 47 (time points t11 to t12).

Therefore, for example, by supplying the hydraulic fluid from the accumulator 47 to the head side chamber 35h and advancing the plunger 21, the advantage of the hydraulic pressure type of high speed can be utilized. On the other hand, when the plunger 21 is retracted by the first electric motor 31A, the accumulator 47 is filled with the hydraulic fluid discharged from the head side chamber 35h by the piston 37, so that the capacity of the pump 49 is reduced as already mentioned. It is easy to reduce the volume of the tank 51.

Here, as another aspect, a mode in which low-speed injection is performed by the first electric motor 31A in a state where the attachment / detachment portion 33 is connected to the piston rod 39, and then high-speed injection is performed by the pressure of the accumulator 47 can be mentioned. Compared to such an embodiment, for example, the injection device 9 of the present embodiment can advance the plunger 21 by the pressure of the accumulator 47 consistently from the start of injection to the high-speed injection. As a result, for example, control is easy. Also, for example, the probability of unintended pressure fluctuations in the hydraulic fluid is reduced.

The injection cylinder 527 may further include a pressurizing member 541 slidably housed within the cylinder member 535. The pressurizing member 541 may have a first surface 541c that receives pressure from the head side chamber 35h and a second surface 541d that receives pressure from the rear chamber on the opposite side. The area of the second surface 541d may be larger than the area of the first surface 541c. The hydraulic circuit 553 may also be configured to control the flow of hydraulic fluid from the first accumulator (accumulator 47) to the rear chamber 35a.

In this case, by increasing the pressure of the accumulator 47 by the pressurizing member 541, a relatively high pressure can be applied to the head side chamber 35h. As a result, for example, when a relatively high casting pressure is required for the injection device 509, the probability that the injection device 509 becomes large is reduced.

The piston rod 39 may have a detachable portion 39z connected to the detachable portion 33. The attached / detached portion 39z may be located outside the cylinder member 35 regardless of the position of the piston 37. Further, the attached / detached portion 39z may have a small diameter portion 39a and a first large diameter portion 39b. The first large diameter portion 39b is located behind the small diameter portion 39a and has a larger diameter than the small diameter portion 39a. The attachment / detachment portion 33 may have an engaging member 76. The engaging member 76 is supported by the movable member 69 and is movable between the engaging position and the disengaging position. The engaging position is a position where the engaging member 76 faces the outer peripheral surface of the small diameter portion 39a and can be engaged rearward with the first large diameter portion 39b. The disengagement position is a position outside the smaller diameter portion 39a in the radial direction than the above-mentioned engaging position, and is a position where the engaging member 76 does not engage with the first large diameter portion 39b. The portion of the engaging member 76 facing the outer peripheral surface of the small diameter portion 39a may have a recess 76a that accommodates a part of the small diameter portion 39a at the engaging position when viewed in the axial direction of the piston rod 39.

In this case, for example, the amount of engagement between the engaging member 76 and the first large diameter portion 39b can be increased with respect to the angular range around the axis of the small diameter portion 39a. As a result, for example, the contact area between the engaging member 76 and the first large diameter portion 39b can be increased, and thus the certainty of engagement can be improved or the contact pressure can be reduced. Further, for example, since the probability that the engaging force is applied to the first large diameter portion 39b only at a specific position around the axis is reduced, the moment that tilts the piston rod 39 can be reduced.

The injection device 9 may have two attachment / detachment portions 33 arranged line-symmetrically with respect to the piston rod 39. The small diameter portion 39a and the first large diameter portion 39b may each have a circular cross-sectional shape. In the two attachment / detachment portions 33, each of the two recesses 76a may have a semicircular shape having a diameter equal to or larger than the diameter of the small diameter portion 39a and smaller than the diameter of the first large diameter portion 39b. The two engaging members 76 may engage with the first large diameter portion 39b over the entire circumference of the small diameter portion 39a around the axis.

In this case, for example, since the engaging member 76 and the first large-diameter portion 39b engage with each other over the entire circumference, the above-mentioned effect due to the provision of the recess 76a is improved.

The hydraulic circuit 53 may have a flow control valve 55 located between the accumulator 47 and the head side chamber 35h. In this case, for example, the forward speed of the plunger 21 can be controlled by a meter-in circuit. In the case of controlling the speed of the plunger 21 by the meter-in circuit, for example, although different from the configuration illustrated in FIG. 4, a configuration in which the rod side chamber 35r is opened to the atmosphere can be adopted.

(Modified example of protruding motion)
In the embodiment, the projecting operation (time points t9 to t10) in which the molded product is pushed by the plunger 21 and separated from the fixed mold 103 is performed by advancing the pressurizing member 541 by the hydraulic pressure device 543. The protruding operation may be performed by the first drive device 29A in addition to or instead of the hydraulic pressure device 543.

The broken lines in "ACC", "first motor" and "detachment" in FIG. 6 indicate the operation of such a modification. For example, the control device 5 first connects the attachment / detachment portion 33 to the attachment / detachment portion 39z of the piston rod 39. Next, the control device 5 rotates the first electric motor 31A in the normal direction and advances the piston rod 39. As a result, the molded product is pushed by the plunger 21 and the mold is released. During this period, unlike the embodiment, the flow control valve 55 and the check valve 59E may be closed, and the flow of the hydraulic fluid from the accumulator 47 to the rear chamber 35a may be prohibited. That is, the pressurizing member 541 may be stopped. The head side chamber 35h may be appropriately replenished with the hydraulic fluid from the accumulator 47 or the like so as not to hinder the advancement of the piston 37.

As described above, the detachable portion 33 may allow or prohibit the advancing of the movable member 69 with respect to the piston rod 39. After the molding material inside the mold 101 is solidified, the control device 5 advances the movable member 69 by the first electric motor 31A in a state where the movable member 69 is prohibited from advancing with respect to the piston rod 39 by the detachable portion 33. The plunger 21 moving forward may be configured to push the solidified molding material away from the mold 101 (more specifically, the fixed mold 103).

In this case, for example, as in the embodiment, the electric first drive device 29A will be used in a process in which high speed is not required. As a result, for example, the load on the hydraulic pressure device 43 can be reduced while taking advantage of the hydraulic pressure type. Further, as compared with the embodiment, for example, since the drive system of the piston rod 39 is an electric type, the accuracy of the speed control of the piston rod 39 is improved. The projecting operation by the first driving device 29A may be combined with the projecting operation by advancing the pressurizing member 541.

<Second Embodiment>
FIG. 7 is a diagram showing a configuration of a main part of the injection device 609 according to the second embodiment, and corresponds to FIG. 4 of the first embodiment. In this figure, the two symbols A indicate positions of the flow path connected to each other.

In the first embodiment, the injection cylinder 527 is a so-called pressure-increasing type having a piston 37 (injection piston) and a pressure member 541 (pressure-increasing piston). On the other hand, in the second embodiment, the injection cylinder 627 is a so-called single cylinder type having a piston 37 and not having a pressure boosting piston (pressurizing member 541). The cylinder member (reference numeral omitted) of the injection cylinder 527 is configured such that the large-diameter cylinder 35y is removed from the cylinder member 535 of the first embodiment and the rear end of the small-diameter cylinder 35x is closed, and the rod side chamber 35r and the rod side chamber 35r are configured. It has a head side chamber 35h and does not have a front side chamber 35f and a rear side chamber 35a.

The hydraulic device 643 of the present embodiment may have a first accumulator 47A and a second accumulator 47B. The first accumulator 47A and the second accumulator 47B may have the same configuration or different configurations from each other. For example, the second accumulator 47B may be configured to be capable of accumulating pressure up to a pressure higher than the pressure of the first accumulator 47A. Note that, unlike the illustrated example, the single cylinder type injection cylinder 527 may be combined with a hydraulic device having a first accumulator 47A and not having a second accumulator 47B.

As can be understood from the comparison between the hydraulic circuit 653 of the present embodiment and the hydraulic circuit 553 of the first embodiment, the first accumulator 47A may be regarded as corresponding to the accumulator 47 of the first embodiment. The second accumulator 47B is connected to the head side chamber 35h by the flow path 54n. The flow path 54n is provided with one or more valves (eg, pressure control valves and / or check valves) (eg, pressure control valves) that prohibit and allow the flow of hydraulic fluid between the second accumulator 47B and the head concubine 35h.

The operation of the injection device 609 according to the second embodiment may be substantially the same as the operation of the injection device 509 according to the first embodiment.

However, in the pressure increasing step (part or all of the latter half), instead of supplying the hydraulic fluid from the accumulator 47 to the rear concubine 35a in the first embodiment, the hydraulic fluid is supplied from the second accumulator 47B to the head concubine 35h. Is realized by doing. Specifically, at least at the time when the pressure increase switching condition (which may be integrated with the pressure increase start condition) described in the first embodiment is satisfied, the pressure of the second accumulator 47B is the pressure of the first accumulator 47A. Higher than the pressure of. Therefore, after the hydraulic fluid is supplied from the first accumulator 47A to the head side chamber 35h to perform injection in a narrow sense (low-speed injection and high-speed injection), the hydraulic fluid is supplied from the second accumulator 47B to the head side chamber 35h to supply the head. The pressure in the side chamber 35h can be further increased to increase the pressure.

Further, when the accumulator is filled with the retreat of the piston 37 (plunger 21) by the first drive device 29A, both the first accumulator 47A and the second accumulator 47B may be filled. This filling may be sequentially performed by the first accumulator 47A and the second accumulator 47B by sequentially allowing the flow of the hydraulic fluid in the flow paths 54a and 54n, and either of them may be filled first. not.

As described above, also in this embodiment, the injection device 609 has an injection cylinder 627, a hydraulic pressure device 643, a first drive device 29A, and a control device 5. The control device 5 starts the advance of the piston 37 by supplying the hydraulic fluid from the first accumulator 47A to the head concubine 35h in a state where the movable member 69 is allowed to retract with respect to the piston rod 39 by the detachable portion 33. It is configured to control the start of injection (time point t0). In the control device 5, the movable member 69 is retracted by the first electric motor 31A in a state where the movable member 69 is prohibited from retracting with respect to the piston rod 39 by the detachable portion 33, and the piston 37 retracting the movable member 69 operates the head side chamber 35h. It is configured to control the liquid to be pushed out to the first accumulator 47A (and the second accumulator 47B). Therefore, the same effect as that of the first embodiment is obtained. For example, it is easy to reduce the capacity of the pump 49 and the volume of the tank 51.

In the present embodiment, the hydraulic pressure device 643 further includes a second accumulator 47B that supplies the hydraulic fluid to the head side chamber via the hydraulic pressure circuit 653.

In this case, for example, a high casting pressure can be obtained while using a single cylinder type injection cylinder 627. Further, by filling not only the first accumulator 47A but also the second accumulator 47B with the retreat of the piston 37 by the first electric motor 31A, the effect of miniaturization of the pump 49 and / or the tank 51 is improved. do.

<Third Embodiment>
8 and 9 are side views and top views showing the configuration of a main part of the die casting machine 1 (machine body 3) according to the third embodiment, and correspond to FIGS. 1 and 2 of the first embodiment. There is. FIG. 10 is a cross-sectional view schematically showing the configuration of a main part of the injection device 9 (driving unit 23 thereof) included in the die casting machine 1, and corresponds to FIG. 3 of the first embodiment. However, in FIG. 10, for convenience, components that cannot be seen from the upper surface (second motor 31B and the like described later) are also shown.

In the first embodiment, the drive system of the pressurizing member 541 is a hydraulic system. On the other hand, in the present embodiment, the drive system of the pressurizing member 41 is an electric type. That is, the injection device 9 has a second drive device 29B including a second motor 31B for driving the pressurizing member 41. Specifically, it is as follows.

(Injection cylinder)
As shown in FIG. 10, the injection cylinder 27 has a piston 37, a pressure member 41, and a cylinder member 35 slidably accommodating them, similarly to the injection cylinder 527 of the first embodiment. There is. However, the cylinder member 35 of the present embodiment is generally configured such that the large-diameter cylinder 35y is removed from the cylinder member 535 of the first embodiment and the rear end of the small-diameter cylinder 35x is closed. That is, the inner diameter of the cylinder member 35 is basically constant in the front-rear direction. The pressurizing member 41 has a columnar shape having a diameter equivalent to that of the piston 37. The portion of the inside of the cylinder member 35 behind the piston 37 is divided into a head side chamber 35h on the piston 37 side and a rear side chamber 35a on the opposite side by the pressurizing member 41. In the injection cylinder 27, the front chamber 35f of the first embodiment does not exist.

The forward movement (and backward movement) of the pressurizing member 41 is realized by the second drive device 29B. Therefore, unlike the first embodiment, the rear concubine 35a may or may not be filled with the hydraulic fluid. For example, the rear concubine 35a may be open to the atmosphere. When the hydraulic fluid is not filled, the rear side chamber 35a may be provided with a small amount of the hydraulic fluid (oil) for lubrication.

When the rear chamber 35a is filled with the hydraulic fluid, the hydraulic fluid may or may not be used for some purpose. As an example of the former, for example, an embodiment in which a hydraulic fluid is supplied from the hydraulic pressure device 43 to the rear side chamber 35a to apply a forward driving force to the pressurizing member 41 can be mentioned. Further, for example, an embodiment may be mentioned in which the hydraulic fluid device 43 prohibits the discharge of the hydraulic fluid from the rear side chamber 35a and prohibits the unintended retreat of the pressurizing member 41. Further, as an example of the latter, an embodiment in which the rear concubine 35a and the tank are only connected can be mentioned.

(Hydraulic device)
FIG. 11 is a circuit diagram showing an example of the hydraulic pressure device 43 included in the injection device 9, and corresponds to FIG. 4 of the first embodiment.

Unlike the first embodiment, the hydraulic pressure device 43 (hydraulic pressure circuit 53) does not have a flow path connecting the accumulator 47 and the rear side chamber 35a and a valve located in the flow path. Since the injection cylinder 27 does not have the front chamber 35f, the hydraulic circuit 53 naturally does not have a flow path or the like related to the front chamber 35f. The check valve 59A may be omitted.

(Second drive device)
Return to FIG. As described above, the second drive device 29B includes the second electric motor 31B and drives the pressurizing member 41. The second drive device 29B has, as a component for transmitting the driving force of the second electric motor 31B to the pressurizing member 41, for example, the second transmission mechanism 67B and the second conversion in order from the second electric motor 31B to the pressurizing member 41. It has a mechanism 68B.

The second electric motor 31B is a rotary electric motor like the first electric motor 31A. The above-mentioned description regarding the configuration of the first motor 31A may be incorporated into the configuration of the second motor 31B as long as there is no contradiction or the like. The second motor 31B may or may not be of the same type (eg, alternating current or direct current, and / or induction or synchronization) as the first motor 31A. Further, the second electric motor 31B may have different performance (rated torque, etc.) from the first electric motor 31A depending on the difference in roles between the first driving device 29A and the second driving device 29B.

The main body (stator) of the second electric motor 31B is fixed to an immovable portion (for example, a cylinder member 35) of the injection device 9, and various parallel movements and rotational movements are restricted. The arrangement position and orientation of the second electric motor 31B may be appropriately set. In the example of FIG. 8, the second electric motor 31B is arranged behind and below the injection cylinder 527. Further, in the example of FIG. 10, the second electric motor 31B is arranged so that the output shaft is parallel to the injection cylinder 27 and faces rearward.

The second transmission mechanism 67B transmits the rotation of the second motor 31B in the same manner as the first transmission mechanism 67A that transmits the rotation of the first motor 31A. The above-mentioned explanation regarding the configuration of the first transmission mechanism 67A may be incorporated into the configuration of the second transmission mechanism 67B as long as there is no contradiction or the like. In the case of use, the word of the first pulley 70A is replaced with the word of the second pulley 70B, the word of the first nut 71A is replaced with the word of the second nut 71B, and the word of the first belt 72A is replaced with the word of the second belt 72B. Replace with a word. The second transmission mechanism 67B may have a gear ratio or the like different from that of the first transmission mechanism 67A depending on the difference in roles between the first drive device 29A and the second drive device 29B.

The specific arrangement position of the second transmission mechanism 67B may be appropriately set. In the illustrated example, the second transmission mechanism 67B is located behind the injection cylinder 27. The second nut 71B is coaxially arranged on the injection cylinder 27. The second pulley 70B is located below the second nut 71B (see the position of the second motor 31B in FIG. 8).

The second conversion mechanism 68B converts the rotational motion of the second electric motor 31B into linear motion in the same manner as the first conversion mechanism 68A that converts the rotational motion of the first electric motor 31A into linear motion. The above-mentioned explanation about the configuration of the first conversion mechanism 68A may be incorporated into the configuration of the second conversion mechanism 68B as long as there is no contradiction or the like. At the time of reference, the word of the first nut 71A is replaced with the word of the second nut 71B, and the word of the first screw shaft 73A is replaced with the word of the second screw shaft 73B. The first conversion mechanism 68A and the second conversion mechanism 68B may have different specific configurations depending on the difference in the roles of the first drive device 29A and the second drive device 29B. For example, the two may differ in type (for example, whether it is a ball screw mechanism or a sliding screw mechanism), a diameter and / or a lead. In the illustrated example, the length of the second screw shaft 73B is shorter than the length of the first screw shaft 73A.

The second conversion mechanism 68B is arranged coaxially with, for example, the injection cylinder 27. The second screw shaft 73B is connected to the pressurizing member 41 and its rotation is restricted. The second nut 71B is allowed to rotate around the axis, and other movements are restricted. Therefore, when the second nut 71B is rotated by the second electric motor 31B, the second screw shaft 73B moves in the axial direction, and eventually the pressurizing member 41 moves in the front-rear direction.

The method of restricting the parallel movement of the second nut 71B and the method of restricting the rotation of the second screw shaft 73B may be appropriate. For example, the second nut 71B may be supported by an appropriate member connected to the cylinder member 35 via a bearing, so that rotation is allowed and other movements are restricted. Further, for example, the second screw shaft 73B may be restricted from rotating around the axis while allowing movement in the axial direction by the spline groove.

Although not particularly shown, the injection device 9 may have a sensor for detecting the rotation speed of the second motor 31B and / or a sensor for detecting the torque of the second motor 31B. The control device 5 may perform control based on these sensors.

(Operation of injection device)
FIG. 12 is a diagram illustrating the operation of the injection device 9, and corresponds to FIG. 6 of the first embodiment.

In this figure, in addition to the operation of the components shown in FIG. 6, the operation of the second electric motor 31B is also shown. As can be understood from the above description, in "ACC", "release", unlike FIG. 6, means only release to the head concubine 35h and does not include release to the posterior concubine 35a. Similarly, "filling" indicates a state in which the hydraulic fluid in the head concubine 35h is filled in the accumulator 47, and does not include filling the accumulator 47 from the rear concubine 35a. In the "first motor", "second motor", and "detachment", the broken line indicates the operation of the modification described later. See the solid line here.

In the first embodiment, the hydraulic fluid is supplied from the accumulator 47 to the rear concubine 35a, whereby the pressurizing member 41 advances. On the other hand, in the present embodiment, the pressurizing member 41 advances by the driving force of the second electric motor 31B. In the first embodiment, when the piston 37 is retracted by the first electric motor 31A, the discharge of the hydraulic fluid from the head side chamber 35h is prohibited and the pressurizing member 41 is retracted. In the present embodiment, the pressurizing member 41 retracts due to the driving force of the second electric motor 31B. In the first embodiment, when the piston 37 is retracted by the first electric motor 31A, the hydraulic fluid is supplied from the head side chamber 35h and the rear side chamber 35a to the accumulator 47. On the other hand, in the present embodiment, the hydraulic fluid is supplied to the accumulator 47 only from the head side chamber 35h. Except for the above, the operation in the present embodiment may be basically the same as the operation in the first embodiment.

The control of the second motor 31B after the start of normal rotation of the second motor 31B (after the start of forward movement of the pressurizing member 41) and before the start of the pressure increase by the second motor 31B (before the time point t5) is speed control. It may be torque control. The speed control may be based on, for example, the detection value of the sensor that detects the speed of the pressurizing member 41, or may be based on the detection value of the sensor that detects the rotation speed of the second electric motor 31B. good. The torque control may be based on, for example, the detection value of the load sensor provided in the transmission path of the driving force of the second motor 31B, or the detection value of the detector that detects the current flowing through the second motor 31B. It may be based on.

Specifically, for example, the control device 5 may control the speed of the second electric motor 31B so that a constant rotation speed is maintained. The rotation speed at this time may be appropriately set. For example, the rotation speed of the second electric motor 31B may be set so that the speed of the pressurizing member 41 is 1/2 or less, 1/5 or less, or 1/10 or less with respect to the target speed of the plunger 21. .. By lowering the rotation speed of the second electric motor 31B, for example, the influence of the pressurizing member 41 on the injection speed is reduced, and the control of the injection speed is facilitated. This facilitates, for example, speed control by a meter-in circuit.

As described above, in the initial stage of the pressure increasing step (time points t4 to t5), the pressure may be controlled by controlling the flow rate control valve 55. At this time, the control of the second electric motor 31B may be speed control or torque control. The various sensors used in speed control or torque control are as described in the description of the control of the second motor 31B before the start of pressure increase. The control device 5 may perform torque control of the second motor 31B so that a constant torque is maintained, for example. The torque at this time may be appropriately set. For example, the torque of the second electric motor 31B may be such that the pressurizing member 41 does not stop or retreat due to the pressure from the head side chamber 35h.

The control when the pressure is increased (time points t5 to t6) by the second electric motor 31B is, for example, pressure control based on the detection value (detection value of injection pressure) of the pressure sensor 97H (and the pressure sensor 97R if necessary). be. The control device 5 feedback-controls the second electric motor 31B so that the detected value of the injection pressure rises along a predetermined step-up curve, for example. As a result, the injection pressure reaches the casting pressure _PE (final pressure).

The time when the flow rate control valve 55 and the check valve 59A are closed and the time when the control device 5 starts the pressure control by the second motor 31B may be before or after. In other words, the condition for closing the flow rate control valve 55 and the check valve 59A and the condition for starting the pressure control by the second motor 31B may be different.

At the holding pressure (time points t6 to t7), the control device 5 may control the second motor 31B so that the final pressure is maintained. Theoretically, since the head side chamber 35h is sealed, the pressure holding is performed by maintaining the position of the pressurizing member 41. However, in reality, since the hydraulic fluid leaks, the pressurizing member 41 may be moved forward as appropriate. For example, the control device 5 may rotate the second electric motor 31B in the forward direction as appropriate while basically stopping the rotation of the second electric motor 31B. The stop of rotation of the second motor 31B at this time may be realized by feedback control or by a brake. When the control device 5 determines that the molten metal has solidified (time point t7), the control device 5 controls the second electric motor 31B so as to end the holding pressure. For example, the control device 5 puts the second electric motor 31B in a torque-free state.

Even in the projecting operation (time points t9 to t10), the pressurizing member 41 advances not by the supply of the hydraulic fluid to the rear side chamber 35a but by the driving force of the second electric motor 31B. The control at this time may be either speed control or pressure control, as in the first embodiment.

The retreat of the pressurizing member 41 (reversal of the second motor 31B, time points t11 to t12) may be performed in parallel with the retreat of the piston 37 (example in the figure) or before or after. The specific start time and speed at which the pressurizing member 41 is retracted may be appropriately set.

As described above, also in this embodiment, the injection device 9 has an injection cylinder 27, a hydraulic pressure device 43, a first drive device 29A, and a control device 5. The control device 5 starts the advance of the piston 37 by supplying the hydraulic fluid from the first accumulator 47A to the head concubine 35h in a state where the movable member 69 is allowed to retract with respect to the piston rod 39 by the detachable portion 33. It is configured to control the start of injection (time point t0). Further, in the control device 5, the movable member 69 is retracted by the first electric motor 31A in a state where the movable member 69 is prohibited from retracting with respect to the piston rod 39 by the detachable portion 33, and the head side chamber 35h is retracted by the retracting piston 37. It is configured to control the hydraulic fluid of the above to be pushed out to the first accumulator (accumulator 47). Therefore, the same effect as that of the first embodiment is obtained. For example, it is easy to reduce the capacity of the pump 49 and the volume of the tank 51.

The injection device 9 may have a second drive device 29B. The injection cylinder 27 may further include a pressurizing member 41 that is driven by the second drive device 29B and pressurizes the hydraulic fluid in the head concubine 35h.

In this case, for example, since the first electric motor 31A connected to the piston rod 39 and the second electric motor 31B connected to the pressurizing member 41 are provided, for example, the load on the hydraulic pressure device 43 is reduced. Is facilitated. As a result, for example, it becomes easy to reduce power consumption and environmental load (reduction of oil as a hydraulic fluid).

The control device 5 is a pressure member 41 by the second electric motor 31B in at least a part (time points t5 to t6) of the pressure increasing step of increasing the pressure of the molding material inside the mold (mold 101) by the plunger 21. It may be configured to control to pressurize the hydraulic fluid in the head side chamber 35h by driving the head chamber 35h.

In this case, for example, the electric second drive device 29B is used in a process in which high speed is not required. As a result, for example, the above-mentioned effect of reducing the load on the hydraulic pressure device 43 is improved while taking advantage of the hydraulic pressure type.

The control device 5 controls the flow rate of the hydraulic fluid supplied from the accumulator 47 to the head side chamber 35h based on the detected value of the pressure applied to the molding material at the initial stage of the pressure increasing process (time points t4 to t5), and then controls the flow rate. , The second electric motor 31B may be controlled based on the detected value of the pressure applied to the molding material to control the continuation of the pressure increasing process.

In this case, for example, the transition from injection (narrow sense) to boosting is performed by the hydraulic pressure method, so that the transition is smoothly performed. Further, for example, it is easy to rapidly increase the injection pressure at the time of transition.

After the molding material in the cavity 107 is solidified, the control device 5 drives the pressurizing member 41 by the second electric motor 31B to pressurize the hydraulic fluid in the head side chamber 35h, and the plunger 21 advances the molding after solidification. It may be configured to control the material to be pushed away from the mold 101 (performing a protruding operation).

In this case, for example, the electric second drive device 29B is used in a process that does not require high speed, as in the pressure increasing process. As a result, for example, the above-mentioned effect of reducing the burden on the hydraulic drive device is improved while taking advantage of the hydraulic drive device. Further, as compared with the embodiment in which the piston rod 39 is driven by the first electric motor 31A (see a modification described later), the electric motor is required to have a smaller area in which the pressure member 41 applies pressure to the working fluid. The force applied can be reduced.

(Modified example of protruding motion)
Similar to the first embodiment, the protruding operation (time points t9 to t10) in which the molded product is pushed by the plunger 21 and separated from the fixed mold 103 is the first drive in addition to or instead of advancing the pressure member 41. It may be done by device 29A. The broken lines in the "first motor", "second motor", and "detachable" in FIG. 12 indicate the operation of such a modification. The operation of the first electric motor 31A and the attachment / detachment portion 33 in the modified example is the same as the operation described with reference to FIG. Unlike the embodiment, the second motor 31B may be stopped during the projecting operation.

<Fourth Embodiment>
FIG. 13 is a diagram showing a hydraulic pressure device 243 (hydraulic pressure circuit 253) of the injection device 209 according to the fourth embodiment, and corresponds to FIG. 4 (FIG. 11 of the third embodiment) of the first embodiment. There is.

The injection device 209 is configured to drive the pressurizing member 41 by the second electric motor 31B, similarly to the injection device 9 of the third embodiment. However, as will be understood from the description described later, the differences between the fourth embodiment and the third embodiment may be applied to the first and second embodiments. Hereinafter, for convenience, the fourth embodiment may be described by comparison with the third embodiment.

In the third embodiment, the flow control valve 55 is located between the accumulator 47 and the head concubine 35h to form a meter-in circuit. On the other hand, in the fourth embodiment, the flow rate control valve 255 is located between the rod side chamber 35r and the tank 51, and constitutes a so-called meter-out circuit. Further, the fourth embodiment has a run-around circuit that recirculates the hydraulic fluid discharged from the rod side chamber 35r to the head side chamber 35h by advancing the piston 37. Specifically, it is as follows.

The configuration of the flow rate control valve 255 may be basically the same as that of the flow rate control valve 55 of the third (first) embodiment. The description of the configuration of the flow rate control valve 55 may be incorporated into the configuration of the flow rate control valve 255 as long as there is no contradiction or the like. The flow rate control valve 255 and the flow rate control valve 55 have different directions of symbols indicating these valves, but this is merely a difference for convenience in the illustration.

As will be described later, the flow rate control valve 255 has a configuration for connecting to a run-around circuit, unlike the flow rate control valve 55. However, when the run-around circuit is not provided, or when the run-around circuit and the meter-out circuit are provided in a mode different from the present embodiment, the flow rate control valve 255 has a configuration for such a connection. Instead, it may have the same configuration as the flow control valve 55.

The flow rate control valve 255 (its main valve 256) is located in the flow path 54e communicating the rod side chamber 35r and the tank 51, and can control the flow rate of the hydraulic fluid flowing from the rod side chamber 35r to the tank 51. By controlling this flow rate, for example, the forward speed of the piston 37 is controlled. The pilot valve 57 of the flow control valve 255 is provided in the accumulator 47 (flow path 54c), the two ports leading to the tank 51 (flow path 54d), and the main valve 256, as in the third (first) embodiment. Continuously switch the connection with the two communicating ports.

The run-around circuit has a flow path 54r that communicates the rod side chamber 35r and the head side chamber 35h, and a valve (check valve 59C in the illustrated example) that allows and prohibits the flow of the hydraulic fluid in the flow path 54r. ..

In the flow path 54r, a flow path 54e (a flow path in which the flow rate control valve 255 is located) that communicates the rod side chamber 35r and the tank 51 branches from a position upstream of the check valve 59C. From another viewpoint, the flow path 54r and the flow path 54e are partially shared on the upstream side of the check valve 59C. However, the flow paths 54r and 54e may be separately connected to the rod side chamber 35r without being partially shared.

The check valve 59C is composed of, for example, a check valve that allows the flow of the hydraulic fluid from the rod side chamber 35r to the head side chamber 35h and prohibits the flow in the opposite direction. In the illustrated example, the check valve 59C is connected to the flow rate control valve 55, and the opening operation is prohibited by the flow rate control valve, as will be described later.

In the circuit configuration as described above, for example, when the check valve 59C is closed and the flow rate control valve 255 is open, the hydraulic fluid discharged from the rod side chamber 35r as the piston 37 advances is the flow rate. It flows to the tank 51 via the control valve 255. At this time, the flow rate discharged from the rod side chamber 35r and the flow rate passing through the flow rate control valve 255 are basically the same (without considering leaks and the like). The flow rate control valve 255 can control the speed of the piston 37 by controlling the flow rate in the same manner as a normal meter-out circuit.

On the other hand, for example, when the check valve 59C is opened and the flow rate control valve 255 is open, a part of the hydraulic fluid discharged from the rod side chamber 35r with the advance of the piston 37 is the check valve 59C. It is returned to the head side chamber 35h via the flow control valve 255, and the rest flows to the tank 51 via the flow rate control valve 255. Therefore, the speed of the piston 37 can be controlled by the flow control valve 255 while reducing the amount of the hydraulic fluid used by the reflux of the hydraulic fluid.

(Connection between check valve and flow control valve)
14 to 16 are sectional views schematically showing the configurations of the main valve 256 and the check valve 59C of the flow rate control valve 255. In this figure, the details are omitted. For example, the port for introducing pilot pressure to the main valve 256 is not shown. FIG. 14 shows a state in which the main valve 256 and the check valve 59C are closed. FIG. 15 shows a state in which the main valve 256 and the check valve 59C are open. FIG. 16 shows a state in which the main valve 256 is opened and the check valve 59C is self-closed.

The structure of the check valve 59C may be basically similar to various structures including known structures. For example, the check valve 59C has a hollow main body 59a, a valve body 59b that can move in the main body 59a in the left-right direction of the paper surface, and a spring 59c that urges the valve body 59b to the left side of the paper surface. The main body 59a has a port 59d leading to the rod side chamber 35r and a port 59e leading to the head side chamber 35h. The specific shape of each member, the positional relationship of the ports, and the like may be appropriately changed.

The basic operation of the check valve 59C may be basically the same as the operation of a known check valve. For example, when the force of the hydraulic fluid from the port 59d pushing the valve body 59b to the right side of the paper surface is smaller than the sum of the force of the hydraulic fluid from the port 59e pushing the valve body 59b to the left side of the paper surface and the urging force of the spring 59c. , The valve body 59b closes the port 59d, and thus the port 59d and the port 59e are cut off (see FIG. 16). That is, the check valve 59C is closed (self-closed). On the other hand, when the former force is larger than the latter force, the valve body 59b is separated from the port 59d, and thus the port 59d and the port 59e are connected (see FIG. 15). That is, the check valve 59C is opened.

The structure of the main valve 256 may be basically similar to various structures including known structures. For example, in the illustrated example, the main valve 256 is configured by a so-called spool type valve. The main valve 256 has a hollow main body 256a and a valve body 256b that can move in the main body 256a in the left-right direction on the paper surface. The main body 256a has a port 256c leading to the rod side chamber 35r and a port 256d leading to the tank 51. The valve body 256b has two enlarged diameter portions 256e and 256f that slide in the main body 256a, and a reduced diameter portion 256h that connects these enlarged diameter portions and has a smaller diameter than these enlarged diameter portions. There is. The specific shape of each member, the positional relationship of the ports, and the like may be appropriately changed.

The basic operation of the main valve 256 may be basically the same as that of a known valve. For example, when one of the two enlarged diameter portions (diameter expanded portion 256f in the illustrated example) blocks one of the two ports (port 256c in the illustrated example), the two ports are blocked (see FIG. 14). .. That is, the main valve 256 is closed. The two ports are connected by retracting one of the enlarged diameter portions (256f) from at least a part of the one port (256c) (see FIGS. 15 and 16). That is, the main valve 256 is opened. The opening degree is defined by the amount of retracting the enlarged diameter portion (256f) from the one port (256c), and the flow rate is defined by the amount.

In the following description, of the moving directions of the valve body 59b of the check valve 59C, the side that moves when the check valve 59C is opened (the right side of the paper) is referred to as the open side, and the opposite side may be referred to as the closed side. .. Similarly, in the moving direction of the valve body 256b of the main valve 256, the side that moves when the main valve 256 is opened (the right side of the paper) is called the open side, and the opposite side may be called the closed side.

The check valve 59C and the main valve 256 differ from the known configuration in that they are connected to each other. Specifically, the connecting member 79 is fixed to the valve body 256b of the main valve 256. The connecting member 79 extends from the valve body 256b in the moving direction of the valve body 256b. Then, the connecting member 79 extends to the outside of the main body 256a of the main valve 256 and is inserted into the main body 59a of the check valve 59C.

As shown in FIG. 14, when the main valve 256 is closed, the connecting member 79 comes into contact with the valve body 59b at the position where the check valve 59C is closed from the open side. As a result, the opening operation of the check valve 59C is prohibited. On the other hand, as shown in FIGS. 15 and 16, when the main valve 256 is open, the connecting member 79 separates from the valve body 59b to the open side. As a result, the check valve 59C can perform the above-mentioned opening operation (FIG. 15) and closing operation (FIG. 16) as a normal check valve.

In the illustrated example, the open side of the check valve 59C and the open side of the main valve 256 are on the same side. The check valve 59C is located on the closed side with respect to the main valve 256. The connecting member 79 extends from the valve body 256b of the main valve 256 to the closed side. As a result, the tip of the connecting member 79 can come into contact with the valve body 59b of the check valve 59C from the open side of the check valve 59C by moving the valve body 256b to the closed side.

In addition to the arrangement and orientation shown in the figure, the check valve 59C and the main valve 256 can be connected in various ways. For example, the connecting member 79 may extend from the valve body 256b to the open side of the main valve 256 and extend from the main body 256a. After that, the connecting member 79 may be bent toward the closed side of the main valve 256 and inserted into the check valve 59C having an open side on the same side as the open side of the main valve 256. At this time, the check valve 59C may be arranged in parallel with the main valve 256, for example.

In the illustrated example, the main valve 256 has a so-called overlap type in which the size of the enlarged diameter portion 256f is larger than the diameter of the port 256c in the moving direction of the valve body 256b. Therefore, even if the valve body 256b moves from the closed position (position in FIG. 14) to the open side, there is an overlapping section in which the port 256c remains closed. Further, in the illustrated example, when the valve body 256b passes through the overlapping section and the port 256c is opened to some extent, the valve body 59b of the check valve 59C can move to the fully opened position.

In addition, unlike the example shown in the figure, when the port 256c is opened to some extent, the valve body 59b can move to the fully opened position (before the port 256c is opened to some extent, the valve body 59b is fully opened. The length of the overlapping section may be set so that it is impossible to move to the position). Further, the main valve 256 may not have an overlapping section.

(Operation of injection device)
As for the operation of the injection device 209, the operation of the hydraulic circuit when supplying the hydraulic fluid from the accumulator 47 to the head side chamber 35h (low-speed injection, high-speed injection, etc.) is the third (first) due to the difference in the above configuration. It differs from the operation of the injection device 9 of the embodiment. Specifically, it is as follows.

(Slow injection)
Immediately before the start of low-speed injection, the hydraulic circuit 253 is controlled so as to basically prohibit the flow of the hydraulic fluid, as in the third (first) embodiment, for example. The main valve 256 and the check valve 59C of the flow control valve 255 are in the state shown in FIG.

When the injection start condition is satisfied, the control device 5 opens the check valve 59A and allows the flow of the hydraulic fluid from the accumulator 47 to the head concubine 35h. Further, the control device 5 opens the flow rate control valve 255 as shown in FIG. By opening the flow control valve 255, the check valve 59C is allowed to open.

The opening degree (flow rate) of the flow rate control valve 255 at this time is relatively small with respect to the pressure of the accumulator 47 and the cross section of the flow path from the accumulator 47 to the head concubine 35h. Therefore, although the rod side chamber 35r is connected to the tank 51 via the flow control valve 255, the pressure of the rod side chamber 35r cannot immediately become the tank pressure (for example, atmospheric pressure), and the head side chamber 35h operates. It rises from the liquid by the pressure applied through the piston 37.

At this time, the area of the piston 37 that receives pressure from the hydraulic fluid of the head side chamber 35h is larger than the area that applies pressure to the hydraulic fluid of the rod side chamber 35r due to the difference in the area of the cross section of the piston rod 39. Therefore, the pressure of the rod side chamber 35r can be higher than the pressure of the head side chamber 35h. As a result, the check valve 59C is opened and is passed through the rod side chamber 35r and the head side chamber 35h (FIG. 15).

As described above, the area of the piston 37 that receives pressure from the hydraulic fluid of the head side chamber 35h is larger than the area that receives pressure from the hydraulic fluid of the rod side chamber 35r. Therefore, when the check valve 59C is opened and the rod side chamber 35r and the head side chamber 35h communicate with each other, the force that the piston 37 receives from the hydraulic fluid of the head side chamber 35h due to the above-mentioned difference in area is generated by the piston 37. It is larger than the force received from the hydraulic fluid of the rod side chamber 35r. As a result, the piston 37 advances, and eventually the plunger 21 advances.

When the plunger 21 advances, a part of the hydraulic fluid discharged from the rod side chamber 35r is returned to the head side chamber 35h via the check valve 59C. The rest is discharged to the tank 51 via the flow control valve 255. The control device 5 performs feedback control of the flow rate control valve 255 so that the speed of the plunger 21 becomes a desired low speed injection speed _VL (FIG. 6).

(High-speed injection)
When the high-speed start condition is satisfied, the control device 5 increases the opening degree of the flow rate control valve 255 as shown in FIG. When the opening degree (flow rate) of the flow rate control valve 255 is set to a certain size, the pressure of the rod side chamber 35r tends to approach the tank pressure and decreases. As a result, the check valve 59C closes by itself (FIG. 16). The control device 5 performs feedback control of the flow rate control valve 255 so that the speed of the plunger 21 becomes a desired high-speed injection speed _VH (FIG. 6).

After that, the control device 5 controls the flow rate control valve 255 so as to perform deceleration injection (speed control) and then increase the pressure (pressure control) by the accumulator 47, as in the third (first) embodiment. .. The opening degree of the flow rate control valve 255 at this time is set to, for example, a size that keeps the check valve 59C self-closing. After that, the flow control valve 255 may be fully opened until, for example, the step of retracting the plunger 21 and replenishing the hydraulic fluid from the pump 49 to the rod side chamber 35r is started.

As described above, also in this embodiment, the injection device 209 includes an injection cylinder 27, a hydraulic pressure device 243, a first drive device 29A, and a control device 5. The control device 5 starts the advance of the piston 37 by supplying the hydraulic fluid from the first accumulator 47A to the head concubine 35h in a state where the movable member 69 is allowed to retract with respect to the piston rod 39 by the detachable portion 33. It is configured to control the start of injection (time point t0). Further, in the control device 5, the movable member 69 is retracted by the first electric motor 31A in a state where the movable member 69 is prohibited from retracting with respect to the piston rod 39 by the detachable portion 33, and the head side chamber 35h is retracted by the piston 37. It is configured to control the hydraulic fluid of the above to be pushed out to the accumulator 47. Therefore, the same effect as that of the first embodiment is obtained. For example, it is easy to reduce the capacity of the pump 49 and the volume of the tank 51.

The rod side chamber 35r may be filled with a hydraulic fluid. The hydraulic circuit 253 may have a tank 51 and a flow control valve 255. The flow control valve 255 may be located between the rod side chamber 35r and the tank 51. In this case, for example, the forward speed of the plunger 21 can be controlled by a meter-out circuit. The meter-out circuit can easily improve the accuracy of the speed control of the plunger 21 as compared with the meter-in circuit, for example.

The hydraulic circuit 253 may have a first flow path (flow path 54r) connecting the rod side chamber 35r and the head side chamber 35h. Further, the hydraulic circuit 253 may have a first valve (check valve 59C) that allows and prohibits the flow of the hydraulic fluid in the flow path 54r. The flow rate control valve 255 of the meter-out circuit may be located in a flow path different from the flow path 54r (a portion of the flow path 54e that is not shared with the flow path 54r). In other words, the flow control valve 255 does not have to intervene between the rod side chamber 35r and the head side chamber 35h. Further, for example, a flow rate control valve other than the flow rate control valve 255 may not be provided between the rod side chamber 35r and the head side chamber 35h.

In this case, for example, the hydraulic fluid can be returned from the rod side chamber 35r to the head side chamber 35h by a run-around circuit including the flow path 54r, and the amount of the hydraulic fluid used can be reduced. Further, when the speed is controlled by the flow rate control valve 255 while refluxing, the port 256d downstream of the flow rate control valve 255 is connected to the tank 51. Therefore, the pressure difference between the upstream side and the downstream side can be increased as compared with the mode in which the downstream port 256d is connected to the head side chamber 35h (see FIG. 18B described later). As a result, for example, the sensitivity of control can be improved.

The first valve (check valve 59C) may be a check valve opened by the pressure of the rod side chamber 35r when the pressure of the rod side chamber 35r is larger than the pressure of the head side chamber 35h by a predetermined pressure difference or more. The flow control valve 255 prohibits the operation of opening the check valve 59C when the flow control valve 255 is closed, and closes and opens the check valve 59C when the flow control valve 255 is open. It may be connected to the check valve 59C so as to allow both of them.

In this case, for example, the original opening / closing function of the check valve 59C can be prohibited or permitted in conjunction with the opening degree of the flow rate control valve 255. Therefore, for example, the control device 5 does not have to separately perform the control for opening the check valve 59C (for example, the control for stopping the introduction of the closing pilot pressure) and the control for opening the flow rate control valve 255, and the control is simple. Be made. Further, unlike the present embodiment, when the injection speed is increased, the control device 5 controls the introduction of the pilot pressure into the check valve 59C to close the check valve 59C (this aspect is also a technique according to the present disclosure). In (included), the pressure of the rod side chamber 35r is high, and there is a high possibility that the check valve 59C will be closed when the hydraulic fluid of the rod side chamber 35r can be returned to the head side chamber 35h. However, in the present embodiment, since the autistic action of the check valve 59C is utilized, such a probability is reduced.

(Modification example)
Hereinafter, modification examples of various components of the injection device will be described. In the following description, for convenience, a modified example of one component (for example, the detachable portion 33) and a modified example of another component (for example, the first conversion mechanism 68A) are shown in combination. However, the modified examples of various components do not need to be used in the combination shown in the figure. Modifications of each component may be appropriately applied to embodiments or combined with modifications of other components not shown in the same figure.

(First modification)
FIG. 17 is a diagram showing a modified example of the drive unit, and corresponds to FIGS. 3 and 10 and the like. In FIG. 17, mainly, a modification of the attachment / detachment portion 33, a modification of the first conversion mechanism 68A for converting the rotational motion of the first motor 31A into a linear motion, a modification of the pressurizing member 41, and a modification of the second motor 31B. An example is shown.

(Modification example 1 of the detachable part)
In FIG. 17, the coupling 25A connecting the plunger 21 and the piston rod 39 has a flange 25a protruding radially outward from the outer peripheral surface of the coupling 25A. The movable member 69 engages with the flange 25a from the rear. As a result, the movable member 69 is restricted from moving forward relative to the piston rod 39, and is allowed to move backward. The portion of the movable member 69 that engages with the flange 25a may be regarded as forming a part of the detachable portion 33A.

The attachment / detachment portion 33A has a hook-shaped engaging member 76A that is swingably supported by the movable member 69. The engaging member 76A has an engaging position (position shown in the figure, which corresponds to “ON” in the figure) that engages with the flange 25a from the front, and a disengaging position that retracts from the engaging position and disengages the engagement. It is possible to move between (corresponding to "OFF" in the figure). As a result, the movable member 69 is prohibited and allowed to retract with respect to the piston rod 39. The engaging member 76A is driven by the actuator 77.

As is understood from the attachment / detachment portion 33A, the attachment / detachment portion may be indirectly connected to the piston rod 39 instead of being directly connected to the piston rod 39. In this case, as a member to which the detachable portion is directly connected, the plunger 21 can be mentioned in addition to the coupling 25A, and the piston rod 39, the coupling 25A and / or the connection-only member fixed to the plunger 21 can be used. Members can be mentioned. In the present disclosure, when referring to attachment / detachment, connection, engagement, etc. to the piston rod 39, unless otherwise specified, and unless there is a contradiction, attachment / detachment, connection, engagement, etc. are not limited to direct ones. Indirect ones are also included.

Further, as is understood from the engaging member 76A, the engaging member is not limited to the one that moves in parallel, but may be one that moves in rotation. Further, the engaging member is not limited to the one that engages with the piston rod 39 both in the front and the rear, and may be one that engages with the piston rod 39 only from the front.

In the example of FIG. 17, the movable member 69 is engaged with the piston rod 39 (more strictly, the coupling 25A) from the rear. This makes it possible, for example, to push out the molded product by the plunger 21 when opening the mold. However, the movable member 69 may be configured not to engage with the piston rod 39 from the rear. From another point of view, the first motor 31A may be used only for the retreat of the plunger 21. As described above, the detachable portion may be configured to prohibit and allow only the retracting of the movable member 69 with respect to the piston rod 39.

(Modification example 1 of conversion mechanism)
In the first conversion mechanism 68A of the first drive device 29A according to the embodiment, the first nut 71A is rotated and the first screw shaft 73A is moved in the front-rear direction. In the example of FIG. 17, contrary to the above, the first screw shaft 73A is rotated and the first nut 71A moves in the front-rear direction. Specifically, it is as follows.

The rotation of the first electric motor 31A is transmitted to the first conversion mechanism 68A by the first transmission mechanism 67C as in the embodiment. However, in the first transmission mechanism 67A of the embodiment, the first nut 71A is also used as the pulley, whereas in the first transmission mechanism 67C of this modification, it is fixed to the rear end of the first screw shaft 73A. A pulley 70C is provided. The first screw shaft 73A is supported by an appropriate bearing in a state where only rotation around the shaft is permitted. Therefore, when the first electric motor 31A is driven, the first screw shaft 73A rotates about the axis.

The first nut 71A is fixed to the movable member 69 by a cylindrical guide shaft 74A. The guide shaft 74A extends in the front-rear direction and is inserted into the plate 45c of the frame 45 so as to be movable in the front-rear direction. Further, the two guide shafts 74A are connected via the movable member 69, and the rotation of each guide shaft 74A around the axis is restricted. As a result, the first nut 71A is only allowed to move in the front-rear direction. Then, when the first screw shaft 73A is rotated by the first electric motor 31A, the first nut 71A moves in the front-rear direction, and eventually the movable member 69 moves in the front-rear direction.

As described above, in the screw mechanism, either the screw shaft or the nut may rotate and any of them may be translated. The screw shaft or nut may not be used as an element of a transmission mechanism (pulley in the illustrated example) that transmits the rotation of the motor. The movable member and the screw shaft or the nut may be directly connected as in the embodiment, or may be connected via another member (guide shaft 74A in FIG. 17). The first conversion mechanism has been described as an example, but the same applies to the second conversion mechanism that converts the rotary motion of the second motor into a linear motion and transmits it to the pressurizing member.

(Modification example 1 of pressure member)
The pressurizing member 41 of the third and fourth embodiments (in other words, the pressurizing member driven by the second electric motor 31B) has a piston shape. On the other hand, the pressure member 41A shown in FIG. 17 is a member having a diameter smaller than the inner diameter of the cylinder member 35. In other words, the area of the cross section (plane orthogonal to the front-rear direction) of the pressurizing member 41A is smaller than the area of the cross section of the piston 37. The specific shape of the pressure member 41A is, for example, a columnar shape.

From another viewpoint, the pressurizing member 41A does not slide in the cylinder member 35, and the inside of the cylinder member 35 is not divided into a head side chamber 35h and a rear side chamber 35a. That is, the entire inside of the cylinder member 35 behind the piston 37 is the head side chamber 35h, and the rear side chamber 35a is not formed.

When such a pressurizing member 41A is used, for example, the area where the pressurizing member 41A applies pressure to the hydraulic fluid by advancing the pressurizing member 41A becomes smaller than that of the piston-shaped pressurizing member 41. As a result, for example, the pressure of the head side chamber 35h can be increased with respect to the torque of the second electric motor.

As is clear from the fact that the pressurizing member does not have to be a piston, the moving direction of the pressurizing member is not limited to the front-rear direction (moving direction of the piston 37). For example, the pressurizing member may be inserted in a direction orthogonal to the front-rear direction with respect to the cylinder member 35 and driven in the orthogonal direction.

(Modification example 1 of motor)
In the third and fourth embodiments, the rotation of the second electric motor 31B is transmitted to the second conversion mechanism 68B via the second transmission mechanism 67B including the pulley / belt mechanism. On the other hand, in the example of FIG. 17, the rotation of the second electric motor 31C is directly transmitted to the second conversion mechanism 68B. Specifically, it is as follows.

The second electric motor 31C has a stator 31a that is fixed to the immovable portion of the injection device and a rotor 31b that rotates with respect to the stator 31a. A second nut 71B of the second conversion mechanism 68B is fixed to the inside of the rotor 31b. As a result, the rotation of the rotor 31b is directly transmitted to the second nut 71B.

In the illustrated example, the second motor 31C and the second nut 71B (from another viewpoint, the second conversion mechanism 68B) are arranged concentrically. However, the second motor may be arranged coaxially with the second conversion mechanism and fixed to the second conversion mechanism. For example, in FIG. 17, the second electric motor may be arranged behind the second conversion mechanism 68B with the output shaft facing forward, and the output shaft and the nut may be fixed.

As described above, the screw mechanism may be rotated by either the nut or the screw shaft. This also applies to the embodiment in which the screw mechanism and the electric motor are directly connected. Further, in FIG. 17, the second electric motor is taken as an example, but the first electric motor may also be directly connected to the first conversion mechanism (for example, a screw mechanism).

(Second modification)
FIG. 18A is a diagram showing a modified example of the first drive device 29A for driving the piston rod 39 by the first electric motor 31A. This figure corresponds to, for example, a part of FIG. FIG. 18A mainly shows a modification of the attachment / detachment portion 33 and a modification of the first conversion mechanism 68A that converts the rotational motion of the first motor 31A into a linear motion.

(Deformation example 2 of the detachable part)
The detachable portion 33B shown in FIG. 18A connects the movable member 69A driven in the front-rear direction (left-right direction on the paper surface) by the first electric motor 31A and the coupling 25B. The attachment / detachment portion 33B is configured by a clamp mechanism that attaches / detaches by exciting and demagnetizing an electromagnet. Specifically, for example, the detachable portion 33B has, for example, an electromagnet 81 including a coil and the like, and a magnetic body 82 such as metal clamped to the electromagnet 81. The electromagnet 81 may be assumed to maintain excitation, for example, while the coil is energized. Alternatively, the electromagnet 81 may include a permanent magnet or the like, and may be excited and degaussed by being energized, and may not require energization while the excitation is maintained.

One of the electromagnet 81 and the magnetic body 82 (magnetic material 82 in this modification) is fixed to the piston rod 39 (strictly speaking, the coupling 25B), and the other (electromagnet 81 in this modification) is the movable member 69A. Is fixed to. Then, by connecting and disconnecting the electromagnet 81 and the magnetic body 82, the piston rod 39 and the movable member 69A are connected and disconnected. The facing direction of the electromagnet 81 and the magnetic body 82 may be an appropriate direction. In the illustrated example, the electromagnet 81 fixed to the movable member 69A faces the magnetic body 82 fixed to the piston rod 39 from the rear.

As can be understood from the example of FIG. 18A, the attachment / detachment portion may be of various types. For example, examples of the attachment / detachment portion other than the embodiment and the example of FIG. 18A include those that perform electrostatic adsorption or vacuum adsorption. Further, for example, the attachment / detachment portion may grip the piston rod 39 in a direction intersecting the front-rear direction. In this case, for example, the attachment / detachment portion may be prohibited from moving relative to the piston rod 39 in the front-rear direction due to frictional force. Further, two or more connecting methods such as engagement, suction (including electromagnetic type) and frictional force may be combined.

(Modification example 2 of conversion mechanism)
In the embodiment, the first conversion mechanism 68A that converts the rotational motion of the first electric motor 31A into a linear motion is configured by a screw mechanism. On the other hand, the first conversion mechanism 68C shown in FIG. 18A is configured by a rack and pinion mechanism. Specifically, the first conversion mechanism 68C has a rack 83 extending in the front-rear direction and a pinion 84 that meshes with the rack 83. The rack 83 moves in the front-rear direction by rotating the pinion 84 by the driving force of the first electric motor 31A. The rack 83 is supported by, for example, a guide member 85 that allows only the rack 83 to move in the front-rear direction, and a movable member 69A is fixed to the tip thereof.

As can be understood from the example of FIG. 18 (a), the conversion mechanism for converting the rotational motion into the linear motion may be of various aspects. The same applies to the second conversion mechanism that converts the rotational motion of the second electric motor 31B into a linear motion. Since the second conversion mechanism may have a short stroke, it may be configured by a link mechanism (including a crank mechanism) or a cam mechanism.

(Third modification example)
FIG. 18B is a diagram showing a modified example of the injection cylinder 27 and the hydraulic pressure circuit 53 of the injection device 9. This figure corresponds to, for example, a part of FIG. 10 according to the third embodiment. FIG. 18B mainly shows a modification of the cylinder member 35, a modification of the pressurizing member 41, and a modification of the hydraulic circuit 53.

(Modification example of cylinder member)
The illustrated cylinder member 35A has a first portion 35b slidably accommodating the piston 37, a second portion 35c in which the pressurizing member 41B is arranged, and a communication portion 35d communicating the two. There is. The cylinder member 35A (second portion 35c) is a pressure member other than the pressure member 41B shown in FIG. 18B (for example, the pressure member 41 of the third embodiment and the pressure member 41A of FIG. 17). It may be combined.

The pressurizing member 41B does not directly pressurize the hydraulic fluid in the head side chamber 35h, but indirectly pressurizes the hydraulic fluid in the head side chamber 35h by pressurizing the hydraulic fluid in the second portion 35c. In the present disclosure, when the pressurizing member pressurizes the hydraulic fluid in the head side chamber, the pressurization includes such indirect pressurization unless otherwise specified, and unless a contradiction or the like occurs. However, the inside of the second portion 35c can also be regarded as a part of the head side chamber 35h.

The communication portion 35d may be a portion that can be regarded as a rigid body, or may be formed of a flexible tube. Further, the communication portion 35d may be omitted and the second portion 35c may be directly connected to the first portion 35b. The second portion 35c may be arranged in parallel with or with respect to the first portion 35b (example in the figure), may be arranged in series, or may be arranged so as to be orthogonal to each other. The diameter of the second portion 35c may be smaller, equal to, or larger than the diameter of the first portion 35b (illustrated example).

By providing the second portion 35c for the pressurizing member separately from the head side chamber 35h, for example, the degree of freedom in designing the shape of the cylinder member is improved. In particular, in the embodiment in which the first portion 35b and the second portion 35c are connected by the communication portion 35d, the degree of freedom in the arrangement of the second portion 35c is improved, and the pressurizing member and the pressurizing member are driven accordingly. 2 The degree of freedom in arranging the drive device is also improved. As a result, for example, it becomes easy to shorten the injection device.

The pressurizing member (not limited to the pressurizing member 41B shown) accommodated in the second portion 35c is opposite to the head concubine 35h as in the first and second embodiments (unlike the illustrated example). It may be driven by supplying the hydraulic fluid to the cylinder chamber on the side, or may be driven by the second electric motor 31B as in the third and fourth embodiments. In the former case, the second portion 35c may have a small-diameter cylinder and a large-diameter cylinder having an inner diameter larger than that of the small-diameter cylinder, unlike the illustrated example. In this case, the pressurizing member may have a small-diameter piston that slides on the small-diameter cylinder and a large-diameter piston that slides on the large-diameter cylinder. That is, the pressure-increasing injection cylinder may be one in which the two cylinders are separated from each other, instead of the one in which the two cylinders are directly connected as in the first embodiment.

The illustrated cylinder member 35A can be regarded as showing a modified example in which the diameter of the second portion 35c is smaller than the diameter of the first portion 35b. This diameter relationship applies not only to the embodiment in which the first site 35b and the second site 35c are communicated by the communication portion 35d, but also to the embodiment in which the first site 35b and the second site 35c are directly connected. It is also good. For example, the relationship of the diameters of this modification may be applied to an embodiment in which the second portion 35c is connected in series to the rear end of the first portion 35b.

(Deformation example 2 of the pressure member)
The pressurizing member 41B shown in FIG. 18B has a diameter equivalent to that of the cylinder member 35A (more strictly, the second portion 35c), and has a cylinder similar to the piston-shaped pressurizing member 41. The member 35A is slid. However, the pressurizing member 41B extends from the inside of the cylinder member 35A to the outside with a constant diameter. In other words, the pressurizing member 41B does not divide the inside of the cylinder member 35A into two, and the rear side chamber 35a in the embodiment is not formed. Such a pressurizing member 41B is driven by a second electric motor 31B, for example, as in the third and fourth embodiments.

(Modification example of hydraulic circuit)
In the fourth embodiment, the flow control valve 255 constituting the meter-out circuit has a flow different from the flow path 54r (flow path constituting the run-around circuit) connecting the rod side chamber 35r and the head side chamber 35h. It is provided in a path (a portion of the flow path 54e connecting the rod side chamber 35r and the tank 51, which is not shared with the flow path 54r). On the other hand, in the example shown in FIG. 18B, the flow rate control valve 55 is located in the flow path 54r. More specifically, the flow rate control valve 55 is located in a portion of the flow path 54r that is shared with the flow path 54e.

A check valve 59D is provided in a portion of the flow path 54r that is not shared with the flow path 54e as a valve capable of allowing or prohibiting the flow of the hydraulic fluid in the flow path 54r. The check valve 59D, for example, prohibits the flow from the rod side chamber 35r to the head side chamber 35h, and allows the flow in the opposite direction. Further, the check valve 59D allows both flows by introducing the pilot pressure. Further, a check valve 59B provided in the flow path 54e in the first embodiment is provided in a portion of the flow path 54e that is not shared with the flow path 54r.

In such a configuration, by closing the check valve 59B and opening the check valve 59D, the hydraulic fluid discharged from the rod side chamber 35r as the piston 37 advances can be returned to the head side chamber 35h. The speed of the piston 37 at this time is controlled by the flow control valve 55. Further, by opening the check valve 59B and closing the check valve 59D, the hydraulic fluid discharged from the rod side chamber 35r as the piston 37 advances can be stored in the tank 51. The speed of the piston 37 at this time is controlled by the flow control valve 55. In the low-speed injection, for example, the hydraulic fluid is returned to the head side chamber 35h, and after the high-speed injection, the hydraulic fluid is stored in the tank 51, for example.

The present invention is not limited to the above embodiments and modifications, and may be implemented in various embodiments.

The molding machine is not limited to the die casting machine. For example, the molding machine may be another metal molding machine, an injection molding machine, or a molding machine that molds a material obtained by mixing wood powder with a thermoplastic resin or the like. .. Further, the molding machine is not limited to the horizontal compaction horizontal injection, and may be, for example, vertical compaction vertical injection, vertical compaction horizontal injection, or horizontal compaction vertical injection. The die casting machine is not limited to the cold chamber machine, and may be, for example, a hot chamber machine. The hydraulic fluid is not limited to oil, and may be, for example, water.

In the description of the embodiment, for convenience, each valve is named by the name of the valve type (check valve, switching valve) exemplified in the figure. However, each valve may be a valve other than the type used for the designation.

In embodiments, the pilot pressures for the various valves were supplied by the accumulator. However, the pilot pressure may be supplied from the pump or from an accumulator separate from the accumulator for driving the plunger.

In the embodiment in which the rod side chamber is filled with the hydraulic fluid, the supply of the hydraulic fluid to the rod side chamber when the piston retracts may be performed from an accumulator different from the accumulator for driving the plunger. This replenishment accumulator may have a lower pressure than the accumulator for driving the plunger.

The meter-in circuit and the meter-out circuit may be combined. The meter-out circuit may be used without being combined with a run-around circuit. The run-around circuit may be combined with a meter-in circuit or a combination of a meter-in circuit and a meter-out circuit.

As mentioned in the description of the fourth embodiment, the first valve (check valve 59C) may be driven separately without being connected to the flow rate control valve (255). The connection between the first valve and the flow rate control valve may be a fluid connection instead of fixing the valve bodies to each other. For example, the pilot pressure for closing the first valve may be introduced into the first valve via the flow control valve by moving the valve body of the flow control valve to the closing side.

Only one first drive device, including the first motor, which is attached to and detached from the piston rod may be provided. In this case, the arrangement position of the first drive device is arbitrary, and may be arranged above the injection cylinder, for example. Further, the driving force of one first motor may be distributed to two first conversion mechanisms (for example, screw mechanisms) arranged symmetrically with respect to the cylinder device. Two second driving devices including the second electric motor and driving the pressurizing member may be provided.

The roles of the first electric motor and the second electric motor may be appropriately set. For example, as mentioned in the description of the embodiment, the first motor may be used to advance the plunger in low speed injection. Further, for example, in the pressure increasing step, the driving force of both the first electric motor and the second electric motor may be transmitted to the plunger. In the pressure increasing step, only the electric pressure control may be performed without the hydraulic pressure control.

The first and / or the second electric motor may be a linear motor instead of a rotary one. In this case, a conversion mechanism for converting rotary motion into linear motion is unnecessary.

When the first and / or second transmission mechanism for transmitting the rotation of the motor is provided, the transmission mechanism is not limited to the pulley / belt mechanism. For example, the transmission mechanism may be a sprocket chain mechanism or a gear mechanism.

From this disclosure, the following concepts can be extracted that do not require that the plunger be initiated forward (injection) by supplying the hydraulic fluid from the accumulator to the head concubine.
(Concept 1)
An injection cylinder connected to the rear end of the plunger that advances in the sleeve extending in the front-rear direction and pushes the molding material into the mold.
A hydraulic device that supplies the hydraulic fluid to the injection cylinder,
The first drive device to be connected to and disconnected from the injection cylinder, and
The second drive device connected to the injection cylinder and
A control device that controls the hydraulic pressure device, the first drive device, and the second drive device.
Have and
The injection cylinder
The piston rod connected to the rear end of the plunger and
With the piston connected to the rear end of the piston rod,
It has a space for slidably accommodating the piston in the front-rear direction, and the space is divided by the piston into a rod side chamber in which the piston rod is located and a head side chamber on the opposite side thereof. With the cylinder member
It has a pressurizing member that pressurizes the hydraulic fluid in the head side chamber.
The hydraulic pressure device is
An accumulator that supplies the hydraulic fluid to the head concubine,
It has a hydraulic circuit that controls the flow of hydraulic fluid between the accumulator and the head concubine.
The first drive device is
With the first motor
A movable member driven in the front-rear direction by the first motor,
It has a detachable portion that allows and prohibits the retreat of the movable member with respect to the piston rod.
The second drive device has a second electric motor that drives the pressurizing member.
In the control device, the movable member is retracted by the first electric motor while the movable member is prohibited from retracting with respect to the piston rod by the detachable portion, and the piston retracting the movable member retracts the movable member to operate the head side chamber. An injection device configured to control the liquid to be pushed out to the accumulator.

1 ... Die casting machine (molding machine), 5 ... Control device, 9 ... Injection device, 19 ... Sleeve, 21 ... Plunger, 27 ... Injection cylinder, 29A ... First drive device, 29B ... Second drive device, 31A ... First Electric motor, 31B ... 2nd electric motor, 33 ... Detachable part, 35 ... Cylinder member, 35h ... Head side chamber, 35r ... Rod side chamber, 37 ... Piston, 39 ... Piston rod, 41 ... Pressurizing member, 43 ... Hydraulic device, 47 ... accumulator, 53 ... hydraulic circuit, 101 ... mold.

Claims (15)

An injection cylinder connected to the rear end of the plunger that advances in the sleeve extending in the front-rear direction and pushes the molding material into the mold.
A hydraulic device that supplies the hydraulic fluid to the injection cylinder,
The first drive device to be connected to and disconnected from the injection cylinder, and
A control device that controls the hydraulic pressure device and the first drive device,
Have and
The injection cylinder
The piston rod connected to the rear end of the plunger and
With the piston connected to the rear end of the piston rod,
It has a space for slidably accommodating the piston in the front-rear direction, and the space is divided by the piston into a rod side chamber in which the piston rod is located and a head side chamber on the opposite side thereof. Has a cylinder member and
The hydraulic pressure device is
A first accumulator that supplies the hydraulic fluid to the head concubine,
It has a hydraulic circuit that controls the flow of the hydraulic fluid between the first accumulator and the head side chamber.
The first drive device is
With the first motor
A movable member driven in the front-rear direction by the first motor,
It has a detachable portion that allows and prohibits the retreat of the movable member with respect to the piston rod.
The control device is
By supplying the hydraulic fluid from the first accumulator to the head side chamber in a state where the movable member is allowed to retreat to the piston rod by the detachable portion, the piston starts to move forward and injection is started. In a state where control is performed and the movable member is prohibited from retreating with respect to the piston rod by the detachable portion, the movable member is retracted by the first electric motor, and the piston retracting the movable member causes the head side chamber to operate. An injection device configured to control the liquid to be pushed out to the first accumulator. The injection cylinder further has a pressurizing member slidably housed in the cylinder member.
The pressurizing member has a first surface that receives pressure from the head concubine and a second surface that receives pressure from the rear concubine on the opposite side.
The area of the second surface is larger than the area of the first surface.
The injection device according to claim 1, wherein the hydraulic circuit is configured to also control the flow of the hydraulic fluid from the first accumulator to the rear concubine. The injection device according to claim 1, wherein the hydraulic device further includes a second accumulator that supplies a hydraulic fluid to the head side chamber via the hydraulic circuit. It also has a second motor,
The injection device according to claim 1, wherein the injection cylinder is driven by the second electric motor and further includes a pressurizing member that pressurizes the hydraulic fluid in the head side chamber. The control device controls to pressurize the hydraulic fluid in the head side chamber by driving the pressurizing member by the second electric motor in at least a part of the pressurizing step of pressurizing the molding material inside the mold by the plunger. The injection device according to claim 4, which is configured to perform the above-mentioned. In the initial stage of the pressure increasing step, the control device controls the flow rate of the hydraulic fluid supplied from the first accumulator to the head side chamber based on the detected value of the pressure applied to the molding material, and then the control device. The injection device according to claim 5, which is configured to control the second electric motor based on the detected value of the pressure applied to the molding material to continue the pressure increasing step. After the molding material inside the mold is solidified, the control device drives the pressurizing member by the second motor to pressurize the hydraulic fluid in the head side chamber, and after solidification by the plunger that advances thereby. The injection device according to any one of claims 4 to 6, which is configured to control the molding material to be pushed away from the mold. The detachable portion also allows and prohibits the advancing of the movable member with respect to the piston rod.
After the molding material inside the mold is solidified, the control device advances the movable member by the first electric motor in a state where the movable member is prohibited from advancing with respect to the piston rod by the detachable portion. The injection device according to any one of claims 1 to 6, which is configured to control the molded material after solidification to be pushed away from the mold by the plunger that moves forward. The piston rod has a detachable portion connected to the detachable portion, which is located outside the cylinder member regardless of the position of the piston.
The attached / detached portion is
Small diameter part and
It has a large diameter portion that is located behind the small diameter portion and has a larger diameter than the small diameter portion.
The detachable portion is supported by the movable member, and has an engaging position that faces the outer peripheral surface of the small diameter portion and can be engaged rearward with the large diameter portion, and a diameter smaller than the engaging position. It has an engaging member that can move between the radial outer side of the portion and the position that does not engage with the large diameter portion.
In the engaging member, the portion of the engaging member facing the outer peripheral surface of the small diameter portion has a recess that accommodates a part of the small diameter portion at the engaging position when viewed in the axial direction of the piston rod. The injection device according to any one of claims 1 to 8. It has two attachment / detachment portions arranged line-symmetrically with respect to the piston rod.
The small-diameter portion and the large-diameter portion each have a circular cross-sectional shape.
In the two attachment / detachment portions, each of the two recesses has a semicircular shape having a diameter equal to or larger than the diameter of the small diameter portion and less than the diameter of the large diameter portion, and the two engaging members are the shafts of the small diameter portion. The injection device according to claim 9, which engages with the large diameter portion over the entire circumference. The injection device according to any one of claims 1 to 10, wherein the hydraulic circuit has a flow rate control valve located between the first accumulator and the head concubine. The rod side chamber is filled with hydraulic fluid.
The hydraulic circuit is
With the tank
The injection device according to any one of claims 1 to 10, further comprising a flow control valve located between the rod concubine and the tank. The hydraulic circuit is
A first flow path connecting the rod side chamber and the head side chamber,
It has a first valve that allows and prohibits the flow of hydraulic fluid in the first flow path.
The injection device according to claim 12, wherein the flow rate control valve is located in a flow path different from the first flow path. The first valve is a check valve opened by the pressure of the rod side chamber when the pressure of the rod side chamber is larger than the pressure of the head side chamber by a predetermined pressure difference or more.
The flow control valve prohibits the operation of opening the check valve when the flow control valve is closed, and both the operation of closing and the operation of opening the check valve when the flow control valve is open. 13. The injection device according to claim 13, which is coupled to the check valve so as to allow the above. The injection device according to any one of claims 1 to 14, and the injection device.
A mold clamping device that opens and closes and clamps the mold,
Molding machine with.

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