JP6860382B2 - Injection device and molding machine - Google Patents

Description

The present disclosure relates to an injection device for injecting a molding material in a liquid or solid-liquid coexisting state into a mold and a molding machine provided with the injection device. The molding machine is, for example, a die casting machine or a plastic injection molding machine.

A so-called hybrid injection device is known in which a molding material is injected into a mold by using both the driving force of a hydraulic (hydraulic) cylinder and the driving force of an electric motor. The hybrid injection device of Patent Document 1 has an injection cylinder connected to a plunger that pushes a molding material into a mold, and an electric motor that moves the injection cylinder. In this injection device, for example, the plunger is advanced by the driving force of the injection cylinder while the injection cylinder is advanced by the electric motor. As a result, the speed of the plunger is the sum of the speed at which the injection cylinder is advanced by the electric motor and the speed at which the plunger is advanced by the driving force of the injection cylinder. As a result, it facilitates the realization of the relatively high speed required for so-called high-speed injection. An injection device having a brake is also known (for example, Patent Documents 2 and 3).

Japanese Unexamined Patent Publication No. 2006-315050 Japanese Unexamined Patent Publication No. 8-318545 Japanese Unexamined Patent Publication No. 2011-156579

The technique of Patent Document 1 causes various inconveniences. For example, it is necessary to control both the electric motor and the injection cylinder, and the electric motor and the injection cylinder interact with each other, which complicates the control. Further, for example, the electric motor needs to exert a driving force corresponding to the force received by the plunger from the molten metal in the mold, and the driving force needs to be maintained in the pressure increasing step and the pressure holding step. As a result, for example, the size of the electric motor is increased, the power consumption is increased, and the amount of heat generated is increased.

It is desirable that at least one of the above inconveniences be eliminated. That is, it is desired to provide an injection device and a molding machine capable of driving a plunger by a hydraulic cylinder and an electric motor.

The injection device according to one aspect of the present disclosure includes a piston connected to a plunger that pushes a molding material into a mold, an injection cylinder having a cylinder portion accommodating the piston portion, and the piston with respect to the cylinder portion. It has an electric motor that generates a driving force for moving the cylinder portion in the moving direction of the cylinder portion, and a stop device that stops the entire cylinder portion at an intermediate position in the movable range. The rear end of the cylinder portion does not communicate with other cylinder portions.

In one example, the stop device is not included in the electric motor, which has a braked member that moves with the movement of the cylinder portion and a braking member that comes into contact with the braked member to stop the movement of the braked member. Includes on- board brakes.

In one example, the electric motor is a rotary type, and a conversion mechanism for converting the rotation of the electric motor into a linear motion and transmitting it to the cylinder portion is provided, and the conversion mechanism transmits the rotation of the electric motor to rotate. It has a rotating member to be rotated and a moving member that transmits linear motion to the cylinder portion, and the braked member is connected to the rotating member so as to rotate together, or the moving member. They are connected so that they move together with respect to the members.

In one example, the braked member is connected to the rotating member so as to rotate together.

In one example, the conversion mechanism is a screw mechanism having a screw shaft extending in the moving direction and a nut screwed to the screw shaft, and the rotating member is the screw shaft and the moving member. Is the nut.

In one example, the braked member and the braking member are arranged coaxially with respect to the screw shaft and face each other with respect to the axial direction of the screw shaft.

In one example, the injection device has an electric control unit that controls the electric motor so as to advance the cylinder portion during a low-speed injection process, and a piston to the cylinder portion during a high-speed injection process following a low-speed injection process. It has a hydraulic pressure control unit that controls the injection cylinder so as to advance with respect to the injection cylinder, and the stop device includes a stop control unit that stops the cylinder unit during the high-speed injection process.

In one example, the stop control unit activates the brake during the high speed injection process.

In one example, the stop control unit controls the position of the electric motor so that the electric motor stops during the high-speed injection process.

In one example, the electric control unit that controls the electric motor so as to advance the cylinder portion during the injection step, and the piston is moved to the cylinder portion during the pressure increasing step and the pressure holding step after the injection step. It has a hydraulic pressure control unit that controls the injection cylinder so as to generate a driving force in a forward direction, and the stop device stops the cylinder unit during the pressure increasing step and the pressure holding step. Includes a stop control unit.

In one example, the stop control unit operates the brake during the pressure increasing step and the pressure holding step.

The molding machine according to one aspect of the present disclosure includes the above-mentioned injection device, a mold-clamping device for mold-clamping a mold, and an extrusion device for extruding a molded product from the mold.

According to the above configuration, the plunger can be suitably driven by the hydraulic cylinder and the electric motor.

The schematic diagram which shows the main part structure of the die casting machine which has the injection apparatus which concerns on embodiment of this disclosure. FIG. 6 is a schematic cross-sectional view showing a main configuration of the injection device of FIG. The block diagram which shows the structure of the signal processing system of the injection apparatus of FIG. The timing chart for demonstrating the operation of the injection apparatus of FIG. 5 (a) to 5 (f) are schematic views showing a main configuration of an injection device according to a modified example.

(Overall configuration of die casting machine)
FIG. 1 is a side view showing a configuration of a main part of the die casting machine 1 according to the embodiment of the present disclosure, including a cross-sectional view in part.

The die casting machine 1 injects a molten metal material (molten metal) into a mold 101 (a space such as a cavity Ca; the same applies hereinafter) and solidifies the molten metal in the mold 101 to perform die casting. It manufactures products (molded products). The metal is, for example, aluminum or an aluminum alloy. It is also possible to use a solid-liquid coexisting metal instead of the molten metal.

The mold 101 includes, for example, a fixed mold 103 and a moving mold 105. In the description of the present embodiment, for convenience, the cross section of the fixed mold 103 or the moving mold 105 is shown by one type of hatching, but these molds may be of a direct carving type or a nested type. It may be a thing. Further, the fixed mold 103 and the moving mold 105 may be combined with a core or the like.

The die casting machine 1 has, for example, a machine main body 3 that performs a mechanical operation for molding, and a control unit 5 that controls the operation of the machine main body 3.

The machine main body 3 includes, for example, a mold clamping device 7 that opens and closes and clamps the mold 101, an injection device 9 that injects molten metal into the mold 101, and a die-cast product fixed mold 103 or a moving mold 105. It has an extrusion device 11 that extrudes from (moving die 105 in FIG. 1). In the machine main body 3, the configurations other than the injection device 9 (for example, the configurations of the mold clamping device 7 and the extrusion device 11) are basically (excluding the portion related to the attachment of the injection device 9), and various known configurations are available. It may be similar to the configuration.

In the molding cycle, the mold clamping device 7 moves the moving mold 105 toward the fixed mold 103 to close the mold. Further, the mold clamping device 7 applies a mold clamping force corresponding to the extension amount of the tie bar (reference numeral omitted) to the mold 101 to perform mold clamping. A cavity Ca having the same shape as the molded product is formed in the mold 101 that has been molded. The injection device 9 injects and fills the molten metal into the cavity Ca. The molten metal filled in the cavity Ca is deprived of heat by the mold 101, cooled, and solidified. As a result, a molded product is formed. After that, the mold clamping device 7 moves the moving mold 105 in the direction away from the fixed mold 103 to open the mold. At this time or after that, the extruder 11 extrudes the molded product from the moving die 105.

The control unit 5 includes, for example, a control device 13 (see FIG. 3) that performs various calculations and outputs a control command, a display device 15 that displays an image, and an input device 17 that receives an operator's input operation. ing. From another viewpoint, the control unit 5 has, for example, a control panel (not shown) having a power supply circuit, a control circuit, and the like, and an operation unit 19 as a user interface.

The control device 13 is provided, for example, on a control panel and an operation unit 19 (not shown). The control device 13 may be appropriately divided or dispersed. For example, the control device 13 includes a lower control device for each of the mold clamping device 7, the injection device 9, and the extrusion device 11, and a higher control device that performs control such as synchronizing between the lower control devices. It may be configured.

The display device 15 and the input device 17 are provided in, for example, the operation unit 19. The operation unit 19 is provided, for example, in a fixed portion of the mold clamping device 7. The display device 15 is composed of, for example, a touch panel including a liquid crystal display or an organic EL display. The input device 17 is composed of, for example, a mechanical switch and the touch panel described above.

When focusing on the injection device 9 of the die casting machine 1, the control unit 5 may be regarded as the control unit of the injection device 9. The same applies to the components of the control unit 5 (for example, the control device 13).

(Injection device configuration)
The injection device 9 has, for example, a sleeve 21 that leads into the mold 101, a plunger 23 that is slidable in the sleeve 21, and an injection drive unit 25 that drives the plunger 23. In the description of the injection device 9, the mold 101 side (left side of the paper in FIG. 1) may be referred to as the front side, and the opposite side may be referred to as the rear side, and the terms forward or backward may be used according to this definition. ..

The sleeve 21 is, for example, a tubular member connected to the fixed mold 103, and a supply port 21a for receiving the molten metal into the sleeve 21 is opened on the upper surface thereof. The plunger 23 has a plunger tip 23a that can slide in the sleeve 21 in the front-rear direction, and a plunger rod 23b whose tip is fixed to the plunger tip 23a.

When the mold clamping of the mold 101 by the mold clamping device 7 is completed, one shot of molten metal is poured into the sleeve 21 from the supply port 21a by a hot water supply device (not shown). Then, when the plunger 23 slides forward in the sleeve 21 from the position shown in the drawing, the molten metal in the sleeve 21 is pushed out (injected) into the mold 101.

(Outline configuration of injection drive unit)
FIG. 2 is a schematic view showing a specific configuration of the injection device 9 (injection drive unit 25). FIG. 2 is basically a view viewed from above, but for convenience of illustration, a part (for example, a hydraulic system) is not limited to this. In addition, FIG. 2 includes a cross-sectional view as appropriate.

The injection drive unit 25 is a so-called hybrid type, and the plunger 23 can be advanced by a hydraulic (for example, hydraulic) type driving force, and the plunger 23 can be advanced by an electric driving force. It is possible. Specifically, the injection drive unit 25 includes an injection cylinder 27 connected to the plunger 23, a hydraulic device 29 for supplying a working liquid to the injection cylinder 27, an electric drive unit 31 for moving the injection cylinder 27, and injection. It has a stop device 33 that regulates the movement of the cylinder 27.

The injection cylinder 27 can move the plunger 23 back and forth by its driving force. Further, the electric drive unit 31 can move the plunger 23 back and forth together with the injection cylinder 27 by moving the injection cylinder 27. By restricting the movement of the injection cylinder 27, the stop device 33 exerts various effects such as facilitation of control.

Specifically, for example, the configurations of the injection cylinder 27, the hydraulic pressure device 29, the electric drive unit 31, and the stop device 33 are as follows.

(Injection cylinder configuration)
The injection cylinder 27 is composed of, for example, a direct-coupled booster cylinder. That is, the injection cylinder 27 includes a cylinder portion 35, an injection piston 37 and a pressure boosting piston 39 that can slide inside the cylinder portion 35, and a piston rod 41 that extends forward (toward the plunger 23 side) from the injection piston 37. doing.

The cylinder portion 35 has, for example, an injection portion 35a and a pressure boosting portion 35b that communicates behind the injection portion 35a and has an inner diameter larger than that of the injection portion 35a. The injection piston 37 is slidable on the injection portion 35a, and the inside of the injection portion 35a is divided into a rod side chamber 35r on the front side and a head side chamber 35h on the opposite side. The pressure boosting piston 39 has, for example, a small diameter portion 39a slidable on the injection portion 35a and a large diameter portion 39b slidable on the pressure boosting portion 35b. The large-diameter portion 39b, for example, divides the inside of the pressure boosting portion 35b into a front side chamber 35f on the front side and a rear side chamber 35e on the rear side.

In the injection cylinder 27 having such a configuration, for example, the injection piston 37 moves forward or backward (reciprocates) by selectively supplying the hydraulic fluid to the head side chamber 35h and the rod side chamber 35r. Further, for example, when the hydraulic fluid is supplied to the rear concubine 35e while the outflow of the hydraulic fluid from the head side chamber 35h is prohibited and the front concubine 35f is set to the tank pressure, the pressure is received before and after the pressure boosting piston 39. The hydraulic fluid in the head side chamber 35h is increased in pressure according to the difference in area.

The injection cylinder 27 may be a so-called single-body type that does not have the pressure boosting portion 35b and the pressure boosting piston 39. In the following description, the description relating to the pressure boosting portion 35b and the pressure boosting piston 39 may be omitted as appropriate.

The injection cylinder 27 is arranged coaxially (in series) behind the plunger 23. The tip of the piston rod 41 is connected to the rear end of the plunger rod 23b. Therefore, the plunger 23 also moves forward and backward as the injection piston 37 and the piston rod 41 move forward and backward. The plunger 23 and the piston rod 41 are connected by, for example, a coupling (reference numeral omitted).

(Configuration of hydraulic pressure device)
The hydraulic device 29 includes, for example, a tank 43 for storing the hydraulic fluid, a pump 45 for delivering the hydraulic fluid in the tank 43, a pump electric motor 47 for driving the pump 45, and an accumulator 49 for supplying the accumulated hydraulic fluid. , These elements and a hydraulic circuit 51 that connects the injection cylinder 27 to each other.

The tank 43 is, for example, an open tank and holds the hydraulic fluid under atmospheric pressure. The tank 43 eliminates the excess or deficiency of the hydraulic fluid in the injection cylinder 27 via the hydraulic circuit 51, for example, and supplies the hydraulic fluid to the accumulator 49 via the pump 45 and the hydraulic circuit 51.

The pump 45 may be, for example, a rotary pump, a plunger pump, a constant capacity pump, or a variable capacity pump. Further, although it is sufficient that the pump 45 can discharge the hydraulic fluid in one direction, the structure may be the same as that of the bidirectional (two-way) pump.

The electric motor 47 for a pump is a rotary electric motor. The pump electric motor 47 may be, for example, a DC motor, an AC motor, an induction motor, or a synchronous motor. The electric motor 47 for a pump 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 47 for a pump may be driven at all times, but in the present embodiment, an embodiment in which the electric motor 47 is driven as needed is taken as an example.

The accumulator 49 may be composed of an appropriate type of accumulator such as a weight type, a spring type, a gas pressure type (including a pneumatic type), a cylinder type, and a Prada type. For example, the accumulator 49 is a gas pressure type, cylinder type or Prada type accumulator, and the pressure is accumulated by compressing the gas (for example, air or nitrogen) held in the accumulator 49. The accumulated hydraulic fluid is supplied to the injection cylinder 27 via the hydraulic pressure circuit 51.

(Hydraulic circuit)
The hydraulic circuit 51 includes an injection cylinder 27 (rod side chamber 35r, head side chamber 35h, front side chamber 35f and rear side chamber 35e), a tank 43, a plurality of flow paths connecting the pump 45 and the accumulator 49 to each other, and the plurality of flows. It has multiple valves that control the flow of hydraulic fluid in the path. The plurality of channels are composed of, for example, steel pipes, flexible hoses or metal blocks. The plurality of valves are, for example, non-pilot type or pilot type check valves, switching valves, and servo valves that control the flow rate.

The hydraulic circuit 51 may be appropriately configured so as to realize the flow of the hydraulic fluid described later. Further, the configuration may be the same as that in the conventional hydraulic injection device. FIG. 2 illustrates some of the main components of the hydraulic circuit 51. Specifically, it is as follows.

For example, the hydraulic circuit 51 is provided in a flow path (reference numeral omitted) connecting the tank 43 or the pump 45 and the accumulator 49, and a check valve 53 provided in the flow path to prevent backflow from the accumulator 49. And have. Thereby, for example, the accumulator 49 can be accumulated by the pump 45.

Further, for example, the hydraulic circuit 51 has a flow path (reference numeral omitted) connecting the accumulator 49 and the head side chamber 35h, and an Acc valve 55 provided in the flow path. The Acc valve 55 is composed of, for example, a pilot type check valve, and when the pilot pressure is not introduced, the flow of the hydraulic fluid from the accumulator 49 to the head concubine 35h is prohibited and the flow in the opposite direction is prohibited. Allows both flows when pilot pressure is introduced. Therefore, for example, by introducing a pilot pressure, the hydraulic fluid can be supplied from the accumulator 49 to the head side chamber 35h, and the injection piston 37 can be advanced.

Further, for example, the hydraulic circuit 51 includes a flow path (reference numeral omitted) connecting the tank 43 or the pump 45 and the rod side chamber 35r, and a flow rate control valve provided in the flow path to control the flow rate in the flow path. Has 57. The flow rate control valve 57 is composed of, for example, a flow rate adjusting valve with pressure compensation, and is used in a servo mechanism from another viewpoint, and is a servo valve capable of steplessly modulating the flow rate according to an input signal. It is composed of.

Therefore, for example, the hydraulic fluid in the rod side chamber 35r whose volume decreases as the injection piston 37 advances can be discharged to the tank 43. At this time, the forward speed of the injection piston 37 can be controlled by controlling the flow rate of the hydraulic fluid discharged from the rod side chamber 35r by the flow rate control valve 57. That is, the flow control valve 57 constitutes a so-called meter-out circuit. Further, for example, it is possible to supply the hydraulic fluid from the pump 45 to the rod side chamber 35r to retract the injection piston 37.

Further, for example, the flow path extending from the accumulator 49 to the tank 43 and the pump 45 and the flow path extending from the rod side chamber 35r to the tank 43 and the pump 45 are shared on the tank 43 and the pump 45 side, and are shared. A switching valve 59 for switching the connection destination between the tank 43 and the pump 45 is provided in the portion. Thereby, for example, with respect to the accumulator 49 or the rod side chamber 35r, the supply of the hydraulic fluid from the pump 45 and the discharge of the hydraulic fluid to the tank 43 can be switched.

(Electric drive unit)
The electric drive unit 31 is configured to drive the cylinder unit 35 in the front-rear direction (in another viewpoint, the moving direction of the injection piston 37 with respect to the cylinder unit 35) by an electric motor, for example. Specifically, the electric drive unit 31 includes a rotary moving electric motor 61, a transmission mechanism 63 that transmits the rotation of the moving electric motor 61, and a cylinder that converts the rotation transmitted by the transmission mechanism 63 into translational motion. It has a screw mechanism 65 that transmits to the portion 35.

The electric drive unit 31 has, for example, two sets of the above-mentioned moving electric motor 61, transmission mechanism 63, and screw mechanism 65 symmetrically. However, the electric drive unit 31 may have only one set of the above combinations, or may have three or more sets. A part of the moving electric motor 61 may be shared between the two sets.

The configuration for supporting the cylinder portion 35 so as to be movable in the front-rear direction may be appropriate. For example, the cylinder portion 35 is mounted on a moving table 67 (see also FIG. 1) supported by a linear guide (not shown). Since FIG. 2 is a schematic view, the cylinder portion 35 and the moving table 67 are integrally shown. The number, shape, fixing method, and the like of the members constituting the cylinder portion 35 and the moving table 67 may be appropriately set.

The mobile electric motor 61 may be a DC motor, an AC motor, an induction motor, or a synchronous motor. The mobile electric motor 61 may be an electric motor with a brake or may not have a brake. The mobile electric motor 61 is configured as, for example, a servomotor, has an encoder 61e for detecting the rotation of the mobile electric motor 61, and is feedback-controlled based on the detection value of the encoder 61e.

In the description of the operation described later, when the moving electric motor 61 is stopped, the moving electric motor 61 may be in a torque-free state or may be controlled to stop at a fixed position. , The brake may be used, and the brake may be used. An appropriate stopping method may be selected depending on the situation in which the mobile electric motor 61 is stopped.

The transmission mechanism 63 is composed of, for example, a pulley / belt mechanism, and has a first pulley 69 fixed to the output shaft of the moving electric motor 61 and a screw mechanism 65 (strictly speaking, a screw shaft 75 described later in this embodiment). ), And a belt 73 bridged to the first pulley 69 and the second pulley 71. Therefore, when the moving electric motor 61 is rotated, the rotation is transmitted to the screw mechanism 65 via the transmission mechanism 63.

The screw mechanism 65 is composed of, for example, a ball screw mechanism or a sliding screw mechanism, and has a screw shaft 75 and a nut 77 screwed to the screw shaft 75.

The screw shaft 75 is arranged parallel to the injection cylinder 27. Further, the screw shaft 75 is supported by an appropriate bearing (not shown), so that the screw shaft 75 is restricted from moving in the axial direction and is allowed to rotate around the shaft. On the other hand, the nut 77 is fixed to the cylinder portion 35 so as to be movable in the axial direction together with the cylinder portion 35, and rotation around the axis is restricted. Therefore, when the screw shaft 75 is rotated, the nut 77 moves in the direction parallel to the plunger 23, and the cylinder portion 35 moves in the front-rear direction.

The nut 77 and the cylinder portion 35 may be fixed directly or indirectly by fixing the nut 77 to the moving table 67. .. In the schematic view of FIG. 2, the nut 77 is fixed to the cylinder portion 35 by being fitted into a hole portion formed in the moving table 67 or the like.

(Stop device)
The stop device 33 includes, for example, a friction type brake 79, which directly regulates the rotation of the screw shaft 75, thereby restricting the movement of the cylinder portion 35. Specifically, it is as follows.

The brake 79 includes, for example, a braked member 81 connected to the screw shaft 75 so as to rotate with the screw shaft 75, and a braking member 83 that comes into contact with the braked member 81 and can regulate the rotation of the braked member 81. Have. As a matter of course, the braking member 83 is restricted from moving in the rotation direction of the braked member 81. The braked member 81 and the braking member 83 are arranged coaxially with the screw shaft 75, and face each other in the axial direction of the screw shaft 75, for example. Then, when one of the braked member 81 and the braking member 83 moves toward the other, they come into contact with each other. As a result, a frictional force is generated between the braked member 81 and the braking member 83 with respect to the rotation of the braked member 81. That is, braking force is generated.

The drive system for bringing the braked member 81 and the braking member 83 close to each other and separated from each other is, for example, an electromagnetic type. Specifically, for example, the braked member 81 is movably supported by a support mechanism 87 schematically shown by a rectangle in a direction opposite to the braked member 81 and the braking member 83, and a spring (not shown). Is urged in a direction away from the braking member 83. Then, as schematically shown, a coil 85 is provided on the braking member 83 side, and when the coil 85 is energized (by operating an electromagnet), the braked member 81 and the brake member 81 and / Or a member (metal member) fixed to the braked member 81 in the support mechanism 87 is attracted to the coil 85. As a result, the braked member 81 and the braking member 83 come into contact with each other.

As an example, a brake that exerts a braking force when energized is given as an example. However, in the brake, the braked member 81 and the braking member 83, which are in contact with each other by a spring, are energized (conversely to the above). It may be separated by an electromagnet). Although the coil 85 is shown on the braking member 83 side, the coil 85 may be provided on the braking member 81 side. In place of or in addition to the braked member 81, the braking member 83 may move in the direction of approaching / separating. Further, various known electromagnetic friction brakes may be appropriately applied.

As can be understood from the above description, the brake 79 can regulate the movement of the cylinder portion 35 at an arbitrary position within the movable range of the cylinder portion 35. Therefore, the brake 79 can stop the cylinder portion 35 at an intermediate position (a position excluding the forward limit and the reverse limit) within the movable range.

(Structure of signal processing system)
FIG. 3 is a block diagram showing an outline of the configuration of the signal processing system of the injection device 9.

The control device 13 includes, for example, a CPU, a ROM, a RAM, and an auxiliary storage device, although not particularly shown. Then, various functional units are constructed by the CPU executing the program stored in the ROM and / or the auxiliary storage device.

Specifically, a hydraulic pressure control unit 89 that controls the injection cylinder 27 via the hydraulic pressure device 29, an electric control unit 91 that controls the moving electric motor 61, and a stop control unit 93 that controls the brake 79 are constructed. .. As shown in the figure, the stop device 33 may be considered to include the stop control unit 93 and the brake 79, and unlike the drawing, the stop device 33 includes only the brake 79 of the stop control unit 93 and the brake 79. It may be perceived as being.

The control device 13 in which various functional units as described above are constructed outputs signals for controlling each unit based on various input signals.

Signals are input to the control device 13, for example, the input device 17, the encoder 61e (FIG. 2), the position sensor 95 for detecting the position of the plunger 23 (see also FIG. 2), and the hydraulic pressure device 29 as appropriate. It is a pressure sensor (not shown) that detects the pressure of the working fluid at a different position. Further, the flow rate control valve 57 may output a signal corresponding to the opening degree to the control device 13.

The control device 13 outputs a signal, for example, a display device 15, a hydraulic circuit 51 (for example, a driver (not shown) and various valves (such as the driver) for supplying electric power to the electric motor 47 for a pump), and a mobile electric motor. A driver (not shown) that supplies electric power to 61, and a brake 79 (a driver (not shown) that supplies electric power to the coil 85).

The position sensor 95, for example, constitutes a linear encoder together with a scale portion (not shown). For example, the position sensor 95 is fixedly provided in front of the cylinder portion 35, and the scale portion is provided on the piston rod 41 and extends in the axial direction thereof. Then, the position sensor 95 indirectly detects the position of the plunger 23 by detecting the position of the scale portion that moves with the movement of the piston rod 41. The position sensor 95 or the control device 13 can detect the speed by differentiating the detected position.

The pressure sensor is provided at an appropriate position in the hydraulic system. For example, although not particularly shown, a pressure sensor for detecting the pressure in the head side chamber 35h and a pressure sensor for detecting the pressure in the rod side chamber 35r are provided, and the control device 13 bases the plunger 23 based on the detection values of these pressure sensors. The pressure applied to the molten metal can be specified. Further, for example, although not particularly shown, a pressure sensor for detecting the pressure of the accumulator 49 is provided, and the control device 13 can determine the completion of filling of the accumulator 49 based on the detected value.

(Operation of injection device)
FIG. 4 is a diagram illustrating the operation of the injection device 9. In FIG. 4, the horizontal axis represents time. The line Lv indicates a change in injection speed, and the line Lp indicates a change in injection pressure. In the graph in which the lines Lv and Lp are drawn, the vertical axis indicates the magnitude of the injection speed and the injection pressure. Further, in the lower part of the graph, the operations of the moving table 67, the injection piston 37, the moving electric motor 61, the brake 79, the flow rate control valve 57, the Acc valve 55, the accumulator 49, and the pump electric motor 47 are shown.

The "forward rotation" of the moving electric motor 61 indicates a state in which the moving table 67 rotates in the forward direction, and the "reverse rotation" indicates a state in which the moving table 67 rotates in the opposite direction. “Stop”, “forward” and “backward” of the injection piston 37 indicate relative movement with respect to the cylinder portion 35. The “control” of the flow control valve 57 indicates a state in which the opening degree is appropriately controlled. The "filling" of the accumulator 49 indicates a state in which the accumulator 49 can be filled (it is not necessary that the filling is performed over the entire range designated as "filling").

The injection device 9 performs low-speed injection, high-speed injection, pressure boosting (pressurization), and pressure holding in order. That is, in the initial stage of injection, the injection device 9 advances the plunger 23 at a relatively low speed in order to prevent air from being entrained in the molten metal, and then fills the molten metal without delaying the solidification of the molten metal. The plunger 23 is advanced at a relatively high speed from the viewpoint of. After that, in order to eliminate sink marks on the molded product, the injection device 9 increases the pressure of the molten metal in the cavity by the force in the forward direction of the plunger 23, and further maintains the increased pressure to wait for the molded product to solidify. .. Specifically, it is as follows.

(Immediately before the start of injection: Immediately before t0)
Immediately before the start of injection, the injection device 9 is in the state shown in FIGS. 1 and 2. That is, the moving table 67 (cylinder portion 35 and nut 77 from another viewpoint) and the injection piston 37 are stopped at an initial position such as a retreat limit. As a result, the plunger 23 is stopped at an initial position such as a retreat limit. The mobile electric motor 61 is stopped. The brake 79 may or may not be activated. Although not shown in FIG. 4, the pressure boosting piston 39 is stopped at an initial position such as a retreat limit.

The hydraulic device 29 is controlled so that the injection piston 37 stops at the initial position. For example, the flow control valve 57 is closed and / or the Acc valve 55 is closed. The same control as at the time of low-speed injection described later may be performed.

Further, the hydraulic pressure device 29 may be filling the accumulator 49 or may have completed the filling. When filling is done, the electric motor 47 for the pump is driven, and the switching valve 59 connects the pump 45 and the accumulator 49. When filling is complete, for example, the pump motor 47 is stopped and / or the switching valve 59 shuts off the pump 45 and the accumulator 49.

(Low speed injection: t0 to t1)
When a predetermined low-speed injection start condition is satisfied, such as when the fixing of the fixed mold 103 and the moving mold 105 is completed and the molten metal is supplied to the sleeve 21, the control device 13 rotates the moving electric motor 61 in the normal direction. .. The driving force is transmitted to the moving table 67 (cylinder portion 35) via the transmission mechanism 63 and the screw mechanism 65. As a result, the plunger 23 advances together with the injection cylinder 27. That is, low-speed injection is performed by the driving force of the electric drive unit 31.

During this time, the injection piston 37 is stopped with respect to the cylinder portion 35. That is, low-speed injection is basically performed only by the driving force of the electric drive unit 31, not by the driving force of the injection cylinder 27.

The hydraulic device 29 is appropriately controlled so that the injection piston 37 is stopped. For example, in the illustrated example, the flow control valve 57 is closed. As a result, the discharge of the hydraulic fluid from the rod side chamber 35r is prohibited, and the advance of the injection piston 37 is restricted.

However, the Acc valve 55 is open. That is, the accumulator 49 is in a state in which the hydraulic fluid can be discharged, as shown by the dotted line. Here, the discharge of the hydraulic fluid from the rod side chamber 35r is prohibited as described above. Therefore, the hydraulic fluid (for example, oil) in the rod side chamber 35r is in a compressed state.

The injection piston 37 slightly advances with respect to the cylinder portion 35 by an amount corresponding to the compression or leakage of the hydraulic fluid in the rod side chamber 35r. However, unless otherwise specified, it is expressed that the injection piston 37 is stopped even if such a slight advance occurs. Further, unlike the illustrated example, the Acc valve 55 can be closed.

At low speed injection, the brake 79 is not activated (it does not regulate the rotation of the screw shaft 75). The pump 45 (pump electric motor 47) is stopped, for example. However, the pump 45 may send the hydraulic fluid to the accumulator 49 side. The compression of the hydraulic fluid in the rod side chamber 35r by supplying the hydraulic fluid to the head side chamber 35h described above can also be performed by the pump 45 instead of the accumulator 49.

The speed of the plunger 23 is controlled by adjusting the rotation speed of the moving electric motor 61. Specifically, the control device 13 feedback-controls the rotation speed of the mobile electric motor 61 based on the detected value of the position sensor 95. The speed feedback control here may be based on the deviation of the speed itself of the plunger 23, or based on the deviation between the target position set with respect to the elapsed time in a predetermined time interval and the current position. It may be a thing (a thing that substantially realizes speed feedback by position feedback that is performed from moment to moment).

The speed of the plunger 23 (low speed injection speed _VL ) in low speed injection is, for example, less than 1 m / s. The specific value of the low-speed injection speed _VL may be appropriately set by the operator. The control device 13 receives the input of the value via the input device 17.

(High-speed injection: t1 to t2)
The control device 13 determines whether or not the position of the plunger 23 has reached a predetermined high-speed switching position in the low-speed injection. The determination may be made as appropriate. For example, the control device 13 determines whether or not the detection position of the position sensor 95 has reached a predetermined high-speed switching position, or determines whether or not a predetermined time has elapsed from the start of injection.

Then, when the control device 13 determines that the high-speed switching position has been reached, the control device 13 controls the hydraulic pressure device 29 so that the injection piston 37 advances with respect to the cylinder portion 35. As a result, the plunger 23 moves forward. Further, the speed at this time is relatively high. That is, high-speed injection is performed by the driving force of the injection cylinder 27.

Specifically, the control device 13 opens the flow rate control valve 57 at an appropriate opening degree. As a result, the discharge of the hydraulic fluid from the rod side chamber 35r is allowed, and eventually the injection piston 37 is allowed to move forward. On the other hand, the accumulator 49 has long been able to supply the hydraulic fluid to the head side chamber 35h. Therefore, the injection piston 37 advances by the hydraulic pressure from the accumulator 49.

The hydraulic fluid discharged via the flow rate control valve 57 is discharged to the tank 43 via, for example, the switching valve 59. Although not particularly shown, a run-around circuit for returning the hydraulic fluid discharged from the rod side chamber 35r to the head side chamber 35h is provided, and instead of the flow to the tank 43, a flow in this run-around circuit is allowed. Good.

The pressure of the accumulator 49 has been applied to the head side chamber 35h for some time, and the hydraulic fluid in the rod side chamber 35r has been compressed in advance. Therefore, the generation of surge pressure caused by the injection piston 37 advancing with the compression of the hydraulic fluid in the rod side chamber 35r is suppressed.

While the injection cylinder 27 is driven, the moving table 67 is stopped. That is, contrary to low-speed injection, high-speed injection is basically performed only by the driving force of the injection cylinder 27, not by the driving force of the electric drive unit 31.

Specifically, the control device 13 stops the mobile electric motor 61 and activates the brake 79. As already described, the stopped mobile electric motor 61 may be in a torque-free state, may be controlled to stop at a fixed position, or may include a brake. Brakes may be used.

The roles or divisions of the moving electric motor 61 and the brake 79 in stopping and maintaining the stop of the moving table 67 may be appropriately set. For example, the moving electric motor 61 may be simply put into a torque-free state, and the movement of the moving table 67 may be restricted mainly by the brake 79. Further, for example, the screw mechanism 65 is configured by the sliding screw mechanism, and the frictional force thereof contributes to the regulation of the movement of the moving table 67, and the brake 79 may assist the movement.

The control device 13 starts the control for stopping the mobile electric motor 61 and the control for operating the brake 79 at substantially the same timing. However, as is clear from the fact that the roles or divisions may be appropriately set as described above, the start timings of both controls may be different from each other.

The speed of the plunger 23 is controlled by adjusting the opening degree of the flow control valve 57. Specifically, the control device 13 feedback-controls the opening degree of the flow rate control valve 57 based on the detected value of the position sensor 95. Note that this velocity feedback control may be based on the deviation of the velocity itself, or may be substantially realized by the position feedback, as in the case of low-speed injection.

After the high-speed injection, at least until the holding pressure (described later) is completed, the plunger 23 is driven by the driving force of the injection cylinder 27 and not by the driving force of the electric drive unit 31 as in the high-speed injection. That is, the moving electric motor 61 is maintained in a stopped state, the brake 79 is maintained in an operating state, and the movement table 67 (cylinder portion 35) is restricted (stopped) from moving.

(Deceleration injection: t2 to t3)
When the molten metal is filled in the cavity Ca to some extent, the plunger 23 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, in order to alleviate the impact at the time of filling, appropriate deceleration control such as reducing the opening degree of the flow control valve 57 when a predetermined deceleration start condition is satisfied such as when the plunger 23 reaches a predetermined deceleration position. May be made.

(Pressure increase: t3 to t4)
When the predetermined pressure increasing start condition is satisfied, the control device 13 controls the hydraulic pressure circuit 51 so as to start the pressure increasing process. The pressure increase start condition is, for example, a predetermined injection pressure based on a detection value of a pressure sensor (not shown) that detects the pressure of the head side chamber 35h (and a pressure sensor (not shown) that detects the pressure of the rod side chamber 35r if necessary). The value of is reached, or the detection position of the plunger 23 detected by the position sensor 95 has reached a predetermined position.

The hydraulic circuit 51 allows the accumulator 49 to discharge the hydraulic fluid from the accumulator 49 to the rear concubine 35e, allows the hydraulic fluid to be discharged from the front concubine 35f to the tank 43, and allows the hydraulic fluid to be discharged from the head concubine 35h in order to start increasing the pressure. And allow the discharge of the hydraulic fluid from the rod side chamber 35r to the tank 43 (for example, the flow control valve 57 is fully opened). As a result, the pressure in the head side chamber 35h is pressurized by the pressure boosting piston 39, the injection pressure rises, and the injection pressure reaches the final pressure P. Further, the injection speed becomes 0 when the molten metal is completely filled in the cavity Ca.

In addition, unlike the illustrated example, when the injection cylinder is a single body type, for example, in the pressure boosting step, except that the speed feedback control of the flow rate control valve 57 is not performed, the injection is generally performed at high speed. Control similar to control is performed. The flow control valve 57 is, for example, fully opened, and the pressure in the head side chamber 35h rises to a pressure equivalent to the pressure in the accumulator 49, and the final pressure P is defined by this pressure. In the pressure boosting type or the single body type, the flow rate control valve 57 can be fully closed at an appropriate timing, and the final pressure P can be defined by the pressure difference between the rod side chamber 35r and the head side chamber 35h.

(Holding pressure: t4 to t5)
The control device 13 maintains a state in which the injection pressure is the final pressure P. Specifically, the control device 13 maintains the state of the hydraulic pressure circuit 51 in the pressure increasing step. While this final pressure P is maintained, the molten metal is cooled and solidified.

The control device 13 appropriately determines whether or not the molten metal has solidified while the pressure is being held. For example, the control device 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 when the final pressure P is obtained. Then, when the control device 13 determines that the molten metal has solidified, the control device 13 ends the holding pressure. For example, the control device 13 stops the supply of hydraulic pressure from the accumulator 49 to the rear concubine 35e.

(Extrusion follow-up: t6 to t7)
After the pressure holding is completed, the control device 13 causes a mold clamping device (not shown) to open the mold, and the extrusion device 11 extrudes the molded product from the fixed mold 103. At this time, the control device 13 controls the driving force for pushing out the biscuit by the plunger 23 so that the injection cylinder 27 and / or the electric driving unit 31 is generated. Note that FIG. 4 illustrates a case where extrusion follow-up is performed by the driving force of the injection cylinder 27.

(Plunger retreat: t8 ~)
After that, the control device 13 retracts the plunger 23 to the initial position. Specifically, the moving electric motor 61 is reversed to retract the moving table 67 (cylinder portion 35), and the hydraulic fluid is supplied from the pump 45 to the rod side chamber 35r to make the injection piston 37 relative to the cylinder portion 35. Retreat.

When the injection piston 37 is retracted, the hydraulic circuit 51 connects the pump 45 and the flow rate control valve 57 side by, for example, a switching valve 59, and opens the flow rate control valve 57. Further, the hydraulic circuit 51 allows, for example, the discharge of the hydraulic fluid from the head side chamber 35h to the tank 43, the supply of the hydraulic fluid from the tank 43 to the front side chamber 35f, and the rear side chamber 35e to the tank 43. Allows drainage of hydraulic fluid. The pressure boosting piston 39 is pushed back by, for example, the injection piston 37. The pressure boosting piston 39 may be retracted by prohibiting the discharge of the hydraulic fluid from the head side chamber 35h, or the accumulator 49 may be filled with the hydraulic fluid discharged from the head side chamber 35h or the rear side chamber 35e.

Further, the control device 13 fills the accumulator 49 at an appropriate time. Specifically, for example, the control device 13 closes the flow rate control valve 57 and supplies the hydraulic fluid from the pump 45 to the accumulator 49 via the switching valve 59. This filling is performed, for example, by the start of the next injection. However, it may be performed during the next low-speed injection.

As described above, in the present embodiment, the injection device 9 includes an injection cylinder 27, a moving electric motor 61, and a stop device 33. The injection cylinder 27 has an injection piston 37 connected to a plunger 23 that pushes a molding material into a mold, and a cylinder portion 35 that houses the injection piston 37. The moving electric motor 61 generates a driving force for moving the cylinder portion 35 in the moving direction of the injection piston 37 with respect to the cylinder portion 35. The stop device 33 stops the cylinder portion 35 at a position in the middle of the movable range of the cylinder portion 35.

Therefore, for example, the stop device 33 can stop the movement of the cylinder portion 35, while the injection piston 37 can be advanced with respect to the cylinder portion 35 to advance the plunger 23. As a result, for example, the combined control of the injection cylinder 27 and the moving electric motor 61 becomes unnecessary, and the control is simplified. As a result, it becomes easy to obtain the desired injection speed with high accuracy. Further, for example, the driving force of the moving electric motor 61 may be smaller than that in the case where the injection piston 37 is advanced with respect to the cylinder portion 35 while advancing the cylinder portion 35. As a result, for example, it is possible to reduce the size of the mobile electric motor 61, reduce the power consumption, and / or reduce the amount of heat generated.

In the present embodiment, the stop device 33 has a brake having a braked member 81 that moves with the movement of the cylinder portion 35 and a braking member 83 that comes into contact with the braked member 81 and stops the movement of the braked member 81. Includes 79.

Therefore, for example, when the injection piston 37 is advanced with respect to the cylinder portion 35 to advance the plunger 23, the retreat of the cylinder portion 35 can be suppressed more reliably. Further, for example, in pressure increasing and holding pressure, if the retreat of the cylinder portion 35 is suppressed by the driving force of the moving electric motor 61, the moving electric motor 61 will generate a large driving force for a relatively long time. As a result, for example, the increase in power consumption, the increase in heat generation amount, and / or the increase in size of the mobile electric motor 61 become remarkable. However, in the present embodiment, since the brake 79 suppresses the retreat of the cylinder portion 35, such an inconvenience is eliminated. This effect becomes remarkable when the moving electric motor 61 is torque-free while the brake 79 is operating.

In the present embodiment, the mobile electric motor 61 is a rotary type. The injection device 9 is provided with a conversion mechanism (screw mechanism 65 in this embodiment) that converts the rotation of the moving electric motor 61 into a linear motion and transmits it to the cylinder portion 35. The screw mechanism 65 includes a rotating member (screw shaft 75 in this embodiment) that is rotated by transmitting the rotation of the moving electric motor 61, and a moving member (nut 77 in this embodiment) that transmits linear motion to the cylinder portion 35. And have. The braked member 81 is connected so as to rotate together with respect to the screw shaft 75, or is connected so as to move together with respect to the nut 77 (the former in the present embodiment).

Therefore, for example, as compared with a mode in which the brake directly brakes the moving table 67 (this mode is also included in the technique according to the present disclosure, see FIG. 5 (e) described later), the brake 79 has a screw mechanism 65. Since the force from the cylinder portion 35 is received through the brake 79, the load on the brake 79 is reduced. On the other hand, for example, as compared with the embodiment in which the brake is provided in the mobile electric motor 61 (this embodiment is also included in the technique according to the present disclosure), the force from the mobile table 67 can be reliably received. It is also possible to easily protect the moving electric motor 61 from impacts and the like.

In the present embodiment, the braked member 81 is connected so as to rotate together with the rotating member (screw shaft 75 in the present embodiment).

Therefore, for example, as compared with a mode in which the braked member 81 is connected so as to move (linearly move) together with respect to the nut 77 (this mode is also included in the technique according to the present disclosure). , The size of the braked member 81 and the braking member 83 with respect to the braking force can be reduced. For example, as can be understood from the modified examples of FIGS. 5 (d) and 5 (e) described later, when the braked member 81 moves linearly, one of the braked member 81 and the braking member 83 is used. Since the moving table 67 extends in the moving direction, the brake tends to be relatively large.

In the present embodiment, the conversion mechanism that converts the rotary motion into a linear motion is a screw mechanism 65 having a screw shaft 75 extending in the moving direction of the injection piston 37 and a nut 77 screwed to the screw shaft 75. .. The rotating member that rotates by transmitting the rotation of the moving electric motor 61 is the screw shaft 75, and the moving member that transmits the linear motion to the cylinder portion 35 is the nut 77. The braked member 81 is connected so as to rotate together with the rotating member (screw shaft 75 in this embodiment).

Therefore, for example, the degree of freedom in the configuration of the brake 79 is high. For example, unlike the present embodiment, in a mode in which the nut 77 rotates and the screw shaft 75 moves (this mode is also included in the technique according to the present disclosure), the screw shaft 75 moves forward or backward. , Protrudes forward or backward of the nut 77. Therefore, the brake that brakes the rotation of the nut 77 needs to be configured in an annular shape so that the screw shaft 75 can be inserted, for example. However, such an inconvenience does not occur in the mode of braking the rotating screw shaft 75 as in the present embodiment.

In the present embodiment, the braked member 81 and the braking member 83 are arranged coaxially with respect to the screw shaft 75 and face each other in the axial direction of the screw shaft 75.

Therefore, for example, in a mode in which the braked member and the braking member face each other in the radial direction of the screw mechanism 65 such as a drum brake, or a pair of braking members in a part of the outer edge of the braked member such as a disc brake. The brake can be easily miniaturized in the radial direction as compared with the mode in which the braked member is sandwiched (these modes are also included in the technique according to the present disclosure). As a result, the screw mechanism 65 can be easily brought closer to the injection cylinder 27, and the possibility that an unintended moment such as a moment around the vertical axis is applied from the screw mechanism 65 to the injection cylinder 27 can be reduced.

In the present embodiment, the injection device 9 has an electric control unit 91 that controls the moving electric motor 61 so as to advance the cylinder unit 35 in low-speed injection, and an injection piston 37 with respect to the cylinder unit 35 in high-speed injection following low-speed injection. It has a hydraulic pressure control unit 89 that controls the injection cylinder 27 so as to move forward. The stop device 33 includes a stop control unit 93 that stops the cylinder unit 35 in high-speed injection.

Therefore, for example, in low-speed injection, the injection speed can be controlled by high-precision control, which is an advantage of the electric type. On the other hand, for example, in high-speed injection, a sufficient injection speed can be obtained by a large driving force, which is an advantage of the hydraulic type. Since the cylinder portion 35 is stopped in high-speed injection, for example, control in high-speed injection is simplified.

In the present embodiment, the stop control unit 93 operates the brake 79 at high speed injection.

Therefore, for example, when the injection cylinder 27 exerts a large driving force for high-speed injection, the retreat of the cylinder portion 35 can be suppressed by the brake 79, so that the load on the moving electric motor 61 can be sufficiently reduced. Further, for example, since the brake 79 is mainly used to regulate the movement of the stopped cylinder portion 35, for example, the coefficient of static friction is sufficiently large to regulate the movement of the cylinder portion 35. It should be. In other words, the brake 79 need not be configured to have a coefficient of kinetic friction that is smaller than the coefficient of static friction. As a result, the brake 79 can be miniaturized.

In the present embodiment, the injection device 9 is a cylinder portion in at least a part (low-speed injection in the present embodiment) of an injection process (injection in a narrow sense that does not include pressure boosting and holding pressure; low-speed injection and high-speed injection in the present embodiment). An electric control unit 91 that controls the moving electric motor 61 so as to advance the 35, and a driving force in a direction that advances the injection piston 37 with respect to the cylinder unit 35 in the pressure increasing step and the pressure holding step after the injection step are generated. It has a hydraulic pressure control unit 89 that controls the injection cylinder 27 as described above. The stop device 33 includes a stop control unit 93 that stops the cylinder unit 35 in the pressure increasing step and the pressure holding step.

Therefore, for example, in injection (in a narrow sense), the injection speed can be controlled by high-precision control, which is an advantage of the electric type. On the other hand, in pressure increasing and holding pressure, a sufficient casting pressure can be obtained by a large driving force, which is an advantage of the hydraulic pressure type.

In the present embodiment, the stop control unit 93 operates the brake 79 in the pressure increasing step and the pressure holding step.

Therefore, for example, when the injection cylinder 27 exerts a large driving force for increasing the pressure and holding the pressure, the retreat of the cylinder portion 35 can be suppressed by the brake 79, so that the load on the moving electric motor 61 can be sufficiently reduced. Can be done. Further, for example, as already described, since the brake 79 is mainly used for restricting the movement of the stopped cylinder portion 35, it is necessary to be configured so that the coefficient of kinetic friction becomes large. It is possible to reduce the size.

In the above embodiment, the die casting machine 1 is an example of a molding machine. The injection piston 37 is an example of a piston. The mobile electric motor 61 is an example of an electric motor. The screw mechanism 65 is an example of a conversion mechanism. The screw shaft 75 is an example of a rotating member. The nut 77 is an example of a moving member.

(Modification example)
5 (a) to 5 (f) are schematic views showing a main part of the injection device according to the modified example. In these figures, the booster piston 39, the moving table 67, and the like are not shown.

As shown in FIG. 5A, the moving electric motor is not limited to the rotary type, and may be a linear motor 201. In this case, no transmission mechanism is required between the linear motor 201 and the cylinder portion 35.

As shown in FIG. 5B, the conversion mechanism that converts the rotation of the rotary moving electric motor 61 into linear motion is not limited to the screw mechanism. In FIG. 5B, the rack and pinion mechanism 203 is illustrated as another example of the conversion mechanism. The rack and pinion mechanism 203 has, for example, a rack 205 having a plurality of teeth arranged in the moving direction of the cylinder portion 35, and a pinion 207 that meshes with the rack 205 and is rotated by the moving electric motor 61. In addition, although not particularly shown, a conversion mechanism may be configured by, for example, a link mechanism.

As shown in FIG. 5C, when the conversion mechanism for converting the rotation of the moving electric motor 61 into linear motion is the screw mechanism 65, the roles of the screw shaft 75 and the nut 77 may be opposite to those of the embodiment. Good. That is, the nut 77 is restricted from moving in the axial direction and is rotated about the axis by the moving electric motor 61. The screw shaft 75 is allowed to move in the axial direction, is fixed to the cylinder portion 35, and is restricted from rotating around the shaft.

As shown in FIGS. 5 (b) and 5 (c) above, the transmission mechanism between the rotary moving electric motor 61 and the conversion mechanism that converts the rotation into linear motion may be omitted. In the example of FIG. 5B, the pinion 207 is fixed to the output shaft of the mobile electric motor 61. In the example of FIG. 5C, the mover of the moving electric motor 61 and the nut 77 are directly fixed concentrically. Similarly, when the conversion mechanism is another type of mechanism, the mover of the moving electric motor 61 may be fixed concentrically or coaxially with respect to the rotating member of the conversion mechanism.

As shown in FIG. 5D, the stop device or brake is not limited to the friction brake. In the example of FIG. 5D, a brake 211 configured by a ratchet mechanism (one-way clutch) is shown. The brake 211 has a rack 213 as a braked member and a claw 215 as a braking member. The rack 213 has a plurality of teeth arranged in the moving direction of the cylinder portion 35. The claw 215 is movable between an engaging position that engages with the teeth of the rack 213 and a position that retracts from the engaging position in a direction away from the rack 213.

As shown in FIG. 5 (d) above, the braked member (rack 213 in FIG. 5 (d)) is rotated by the moving electric motor 61 of the conversion mechanism (screw mechanism 65 in FIG. 5 (d)). It is not connected to the rotating member (screw shaft 75 in FIG. 5D) so as to rotate together, but to a moving member (nut 77 in FIG. 5D) that transmits linear motion to the cylinder portion 35. On the other hand, they may be connected so as to move together.

From another point of view, as shown in FIG. 5D, the brake may directly brake the movement of the cylinder portion 35. In FIG. 5D, the rack 213 is directly fixed to the moving table 67, but even when the rack 213 is directly fixed to the cylinder portion 35 and the nut 77, the cylinder portion 35 moves. May be included in the category of those that directly brake.

Although not particularly shown, contrary to FIG. 5D, in a brake other than the friction brake, the braked member is connected so as to rotate together with the rotating member rotated by the moving electric motor 61. It may be a member. For example, a rotary one-way clutch may be attached to the rotating member of the screw mechanism 65.

As shown in FIG. 5 (e), even when the brake is a friction brake, the braked member 223 is connected so as to move together with respect to the moving member (nut 77) as in FIG. 5 (d). It may be a member. From another point of view, the friction brake may directly brake the cylinder portion 35. In the example of FIG. 5 (e), the brake 221 is movable between the braked member 223 extending in the moving direction of the cylinder portion 35, the position where the braked member 223 is in contact with the braked member 223, and the position where the brake 221 is separated from the braked member 223. It has a member 225 and.

As shown in FIG. 5 (e) above, the drive system for operating the brake (driving at least one of the braked member and the braking member) is not limited to the electromagnetic system. In the example of FIG. 5 (e), the braking member 225 is driven by the cylinder 227. The cylinder 227 may be of a hydraulic type or a gas pressure type. In addition, for example, a voice coil motor may be used. The brake 221 of FIG. 5 (e) is of a friction type in which the braked member 223 moves linearly, but similarly, an appropriate drive system may be adopted for a rotary brake and a brake other than the friction type. ..

As shown in FIG. 5 (f), the stop device may not have a brake and may have only a stop control unit 93. Then, the stop control unit 93 may control the position of the moving electric motor 61 so that the moving electric motor 61 stops in high-speed injection, pressure increasing and / or holding pressure. Even in this case, simple control is possible and the burden on the moving electric motor 61 is reduced as compared with the case where the cylinder portion 35 is advanced by the moving electric motor 61 in high-speed injection, pressure increasing and / or holding pressure. can do.

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

The molding machine (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 for molding a resin, or a molding machine for molding a material obtained by mixing wood powder with a thermoplastic resin or the like. There may be. Further, the molding machine is not limited to the horizontal clamping horizontal injection, and may be, for example, vertical clamping vertical injection, horizontal clamping vertical injection, or vertical clamping horizontal injection. The molding material is not limited to a liquid material, and may be a solid-liquid coexisting material such as a semi-solidified metal or a semi-molten metal.

The liquid used for the injection cylinder is not limited to oil, and may be, for example, water. The plunger may be screw-shaped. Instead of or in addition to the meter-in circuit, a flow rate adjusting valve (meter-out circuit) for controlling the flow rate of the hydraulic fluid to the head side chamber may be provided.

The injection is not limited to those having low-speed injection and high-speed injection, and may be, for example, one in which the injection speed is constant or continuously increases from the start of injection to the start of pressure increase. In addition, the process of utilizing the stop device or the brake may be arbitrarily selected. For example, the brake may not be used in high-speed injection, but the brake may be used in boosting and / or holding pressure.

1 ... Die casting machine (molding machine), 9 ... Injection device, 23 ... Plunger, 27 ... Injection cylinder, 35 ... Cylinder part, 37 ... Injection piston (piston), 61 ... Mobile electric motor (electric motor), 33 ... Stop device.

Claims (11)

A piston connected to a plunger that pushes the molding material into a mold, an injection cylinder having a cylinder portion accommodating the piston, and an injection cylinder.
An electric motor that generates a driving force that moves the entire cylinder portion in the direction of movement of the piston with respect to the cylinder portion.
A stop device that stops the cylinder at an intermediate position within its movable range,
Have and
The rear end of the cylinder portion does not communicate with other cylinder portions and
The stop device has a brake member that moves with the movement of the cylinder portion and a braking member that comes into contact with the braked member to stop the movement of the braked member, and is not mounted on the electric motor. Injecting equipment including. The electric motor is rotary and
A conversion mechanism is provided that converts the rotation of the electric motor into linear motion and transmits it to the cylinder portion.
The conversion mechanism is
A rotating member that is rotated by transmitting the rotation of the electric motor,
It has a moving member that transmits linear motion to the cylinder portion.
The braked member may, injection apparatus according to claim 1 which is coupled for movement together relative to both is connected so as to rotate, or the moving member relative to the rotary member. The injection device according to claim 2 , wherein the braked member is connected to the rotating member so as to rotate together. The conversion mechanism is a screw mechanism having a screw shaft extending in the moving direction and a nut screwed to the screw shaft.
The rotating member is the screw shaft.
The injection device according to claim 2 or 3 , wherein the moving member is the nut. The braked member and the braking member is injection according to claim 4 together are arranged coaxially with the screw shaft, citing claim 3 are opposed to each other with respect to the axial direction of the screw shaft apparatus. An electric control unit that controls the electric motor so as to advance the cylinder unit during a low-speed injection process.
A hydraulic control unit that controls the injection cylinder so as to advance the piston with respect to the cylinder unit during the high-speed injection process following the low-speed injection process.
Have and
The injection device according to any one of claims 1 to 5 , wherein the stop device includes a stop control unit that stops the cylinder portion during the high-speed injection step. The injection device according to claim 6 , wherein the stop control unit operates the brake during the high-speed injection process. The injection device according to claim 6 or 7 , wherein the stop control unit controls the position of the electric motor so that the electric motor stops during the high-speed injection process. An electric control unit that controls the electric motor so as to advance the cylinder unit during the injection process.
A hydraulic pressure control unit that controls the injection cylinder so as to generate a driving force in a direction for advancing the piston with respect to the cylinder unit during the pressure increasing step and the pressure holding step after the injection step.
Have and
The injection device according to any one of claims 1 to 8 , wherein the stop device includes a stop control unit that stops the cylinder unit during the pressure increasing step and the pressure holding step. The stop control unit operates the brake during the pressure increasing step and the pressure holding step.
Injection device according to請Motomeko 9. The injection device according to any one of claims 1 to 10, and the injection device.
A mold clamping device that clamps the mold and
An extruder that extrudes a molded product from the mold,
Molding machine equipped with.

Images