JP2021030293A - Injection device and molding machine - Google Patents

Abstract

To provide an electrically-operated injection device that can be improved in high-speed characteristics and acceleration characteristics.SOLUTION: The injection device according to an embodiment comprises: a first member that injects a material into a mold of a molding machine, can connect to the injected material extending in a first direction, has a first rack and extends in the first direction; a second member that has a first pinion gear that is combined with the first rack and a second pinion gear that rotates in tandem with the first pinion gear, and extends in the first direction; a third member having a second rack that is combined with the second pinion gear; and a first motor that moves the first member and the second member in the first direction.SELECTED DRAWING: Figure 2

Description

The present invention relates to an electric injection device and a molding machine.

In a molding machine such as a die casting machine or an injection molding machine, an injection device for injecting a material into a cavity in a mold is provided. From the viewpoints of improving the working environment, energy saving, space saving, and resource saving, it is desired to realize an electric injection device that does not use a hydraulic mechanism as much as possible.

Patent Document 1 describes an electric injection device for a die casting machine capable of performing a required high-speed injection process using a small electric servomotor. However, with the electric injection device of Patent Document 1, it is difficult to realize high-speed characteristics and acceleration characteristics sufficient for actual use.

Japanese Unexamined Patent Publication No. 2012-187609

An object to be solved by the present invention is to provide an electric injection device capable of improving high-speed characteristics and acceleration characteristics.

The injection device according to one aspect of the present invention has a first rack, which can inject materials into a mold of a molding machine and can be connected to an injection member extending in the first direction, and has a first rack extending in the first direction. It has a member, a first pinion gear combined with the first rack, and a second pinion gear that rotates in conjunction with the first pinion gear, and extends in the first direction. A second member, a third member having a second rack combined with the second pinion gear, and a first member that moves the first member and the second member in the first direction. It is equipped with a motor.

In the injection device of the above aspect, the number of teeth of the second pinion gear is preferably equal to or less than the number of teeth of the first pinion gear.

In the injection device of the above aspect, it is preferable that the first motor applies a driving force to at least one of the rotation shafts of the first pinion gear and the second pinion gear.

In the injection device of the above aspect, a support rod extending in the first direction and connected to the second member is further provided, and the first motor applies a driving force to the support rod to cause the support rod. It is preferable to move it in the first direction.

In the injection device of the above aspect, a nut combined with the support rod is further provided, the support rod is a screw shaft, and the first motor rotates the nut to move the support rod in the first direction. It is preferable to move to.

In the injection device of the above aspect, the accumulator fixed to the second member is further provided, and the first member has a piston rod and a piston connected to the piston rod, and the second member. It is preferable that the member of the accumulator has a cylinder that slidably accommodates the piston and includes a head side chamber behind the piston, and the accumulator supplies liquid to the head side chamber.

In the injection device of the above aspect, the second motor and the pressurizing member for pressurizing the liquid supplied to the head side chamber are further provided, and the second motor applies a driving force to the pressurizing member. Is preferable.

In the injection device of the above aspect, a connecting portion for connecting the rear end of the injection member and the front end of the piston rod is further provided, and the connecting portion is provided between the rear end of the injection member and the front end of the piston rod. It is preferable that the piston rod and the piston are formed with a communication passage for communicating the head side chamber and the surge pressure absorption chamber.

In the injection device of the above aspect, the number of teeth of the first pinion gear is preferably twice or more the number of teeth of the second pinion gear.

The molding machine of one aspect of the present invention includes the injection device of the above aspect.

According to the present invention, it is possible to provide an electric injection device capable of improving high-speed characteristics and acceleration characteristics.

The schematic diagram which shows the whole structure of the molding machine of 1st Embodiment. The schematic diagram of the main part of the injection apparatus of the molding machine of 1st Embodiment. The schematic diagram explaining the operation of the injection apparatus of the molding machine of 1st Embodiment. The schematic diagram explaining the operation of the injection apparatus of the molding machine of 1st Embodiment. The schematic diagram of the main part of the injection apparatus of the molding machine of the 2nd Embodiment. The schematic diagram of the main part of the injection apparatus of the molding machine of the 2nd Embodiment. The schematic diagram of the main part of the injection apparatus of the molding machine of the 3rd Embodiment. The schematic diagram of the main part of the injection apparatus of the molding machine of the 3rd Embodiment. The schematic diagram of the main part of the injection apparatus of the molding machine of 4th Embodiment. The schematic diagram of the main part of the injection apparatus of the molding machine of 4th Embodiment. The schematic diagram of the main part of the injection apparatus of the molding machine of 4th Embodiment. The schematic diagram of the main part of the injection apparatus of the molding machine of 4th Embodiment. FIG. 6 is a schematic view of a main part of an injection device of a molding machine according to a fifth embodiment. FIG. 6 is a schematic view of a main part of an injection device of a molding machine according to a fifth embodiment. FIG. 6 is a schematic view of a main part of an injection device of a molding machine according to a fifth embodiment. FIG. 6 is a schematic view of a main part of an injection device of a molding machine according to a fifth embodiment. The schematic diagram of the main part of the injection apparatus of the molding machine of 6th Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In this specification, hydraulic pressure will be used as an example of hydraulic pressure. For example, a hydraulic mechanism will be described as an example of a hydraulic mechanism, and oil will be used as an example of a liquid that generates hydraulic pressure. For example, water pressure can be used instead of hydraulic pressure. Further, in the present specification, a hydraulic oil will be used as an example of the hydraulic fluid.

(First Embodiment)
The injection device of the first embodiment is capable of injecting a material into a mold of a molding machine and connected to an injection member extending in the first direction, having a first rack and extending in the first direction. Member, a first pinion gear combined with the first rack, and a second pinion gear that rotates in conjunction with the first pinion gear, and a second member extending in the first direction. A third member having a second rack combined with the second pinion gear, and a first motor for moving the first member and the second member in the first direction.

Further, the molding machine of the first embodiment includes the above-mentioned injection device.

The number of teeth of the second pinion gear is, for example, equal to or less than the number of teeth of the first pinion gear. Hereinafter, in the first embodiment, a case where the number of teeth of the second pinion gear is the same as the number of teeth of the first pinion gear will be described as an example.

FIG. 1 is a schematic view showing the overall configuration of the molding machine of the first embodiment. FIG. 1 is a side view including a cross-sectional view in part.

The molding machine of the first embodiment is a die casting machine 100. The die casting machine 100 is an example of a molding machine. The die casting machine 100 of the first embodiment is a cold chamber type die casting machine.

The die casting machine 100 includes a mold clamping device 10, an extrusion device 12, an injection device 14, a mold 18, and a control unit 20.

The die casting machine 100 includes a base 22, a fixed die plate 24, a movable die plate 26, a link housing 28, and a tie bar 30.

The die casting machine 100 manufactures a die casting product by injecting a liquid metal (molten metal) into the inside of the mold 18 (cavity Ca in FIG. 1) to fill the mold 18 and solidifying the liquid metal in the mold 18. It is a machine. The metal is, for example, aluminum, an aluminum alloy, a zinc alloy, or a magnesium alloy.

The mold 18 includes a fixed mold 18a and a movable mold 18b. The mold 18 is provided between the mold clamping device 10 and the injection device 14.

The fixed die plate 24 is fixed on the base 22. The fixed die plate 24 can hold the fixed mold 18a.

The movable die plate 26 is provided on the base 22 so as to be movable in the mold opening / closing direction. The mold opening / closing direction means both the mold opening direction and the mold closing direction shown in FIG. The movable die plate 26 can hold the movable mold 18b facing the fixed mold 18a.

The link housing 28 is provided on the base 22. One end of the link mechanism constituting the mold clamping device 10 is fixed to the link housing 28.

The fixed die plate 24 and the link housing 28 are fixed by the tie bar 30. The tie bar 30 supports the mold clamping force while the mold clamping force is applied to the fixed mold 18a and the movable mold 18b.

The mold clamping device 10 has a function of opening and closing the mold 18 and mold clamping.

The injection device 14 has a function of injecting the molten metal into the cavity Ca of the mold 18 and pressurizing the molten metal. The injection device 14 includes an injection sleeve 40, an injection plunger 42 (injection member), a coupling 44 (connecting portion), a position sensor 46, and an injection actuator 51. The injection plunger 42 includes an injection plunger tip 42a and an injection plunger rod 42b.

The injection sleeve 40 leads to the cavity Ca of the mold 18. The injection sleeve 40 is, for example, a tubular member connected to the fixed mold 18a. The injection sleeve 40 has, for example, a cylindrical shape.

The injection plunger 42 slides in the injection sleeve 40. The injection plunger 42 extends in the first direction.

The injection plunger tip 42a fixed to the tip of the injection plunger rod 42b slides in the injection sleeve 40 in the front-rear direction (first direction). When the injection plunger tip 42a slides forward in the injection sleeve 40, the molten metal in the injection sleeve 40 is pushed out into the mold 18.

After the molten metal is filled in the cavity Ca of the mold 18, the injection plunger 42 pressurizes the molten metal to apply pressure to the molten metal.

For example, a hot water supply port (not shown) is provided on the upper part of the injection sleeve 40. For example, a molten metal is supplied into the injection sleeve 40 from a hot water supply port by a ladle (not shown).

The coupling 44 has a function of connecting the injection plunger rod 42b of the injection plunger 42 and the injection actuator 51.

The extrusion device 12 has a function of extruding the manufactured die-cast product from the mold 18.

The control unit 20 includes a control device 32, an input device 34, and a display device 36. The control unit 20 has a function of controlling the molding operation of the die casting machine 100 using the mold clamping device 10, the extrusion device 12, and the injection device 14.

The input device 34 receives an operator's input operation. The operator can set the molding conditions and the like of the die casting machine 100 by using the input device 34. The input device 34 is, for example, a touch panel using a liquid crystal display or an organic EL display.

The display device 36 displays, for example, the molding conditions, the operating status, and the like of the die casting machine 100 on the screen. The display device 36 is, for example, a liquid crystal display or an organic EL display.

The control device 32 has a function of performing various calculations and outputting a control command to each part of the die casting machine 100. The control device 32 has a function of storing, for example, molding conditions and the like. The control device 32 controls, for example, the operation of the injection device 14.

The control device 32 is composed of, for example, a combination of hardware and software. The control device 32 includes, for example, a CPU (Central Processing Unit), a semiconductor memory, and a control program stored in the semiconductor memory.

FIG. 2 is a schematic view of a main part of the injection device of the molding machine of the first embodiment. FIG. 2A is a top view and FIG. 2B is a side view. FIG. 2 is a schematic view including an injection actuator 51 of the injection device 14.

The injection actuator 51 includes an extrusion rod 60 (first member), a movable stage 62 (second member), a fixing base 64 (third member), and a drive motor 66 (first motor). The extrusion rod 60 has a first rack 60a. The movable stage 62 has a first pinion gear 62a, a second pinion gear 62b, and a drive transmission belt 62c. The fixed base 64 has a second rack 64a.

The injection actuator 51 includes a first rack and pinion mechanism and a second rack and pinion mechanism. The first rack and pinion mechanism is composed of a combination of the first rack 60a and the first pinion gear 62a. The second rack and pinion mechanism is composed of a second rack 64a and a second pinion gear 62b.

The extrusion rod 60 is, for example, a round bar. The extrusion rod 60 extends in the stretching direction (first direction) of the injection plunger 42. The extrusion rod 60 has a function of pushing out the injection plunger 42. The extrusion rod 60 has a function of moving the injection plunger 42 in the first direction.

The extrusion rod 60 can be connected to the injection plunger 42. The extrusion rod 60 can be connected to the injection plunger rod 42b. The extrusion rod 60 is connected to the injection plunger rod 42b using, for example, a coupling 44.

The extrusion rod 60 has a first rack 60a. For example, first racks 60a are provided on both side surfaces of the extrusion rod 60.

The extrusion rod 60 is movably supported with respect to the movable stage 62 using, for example, a linear motion guide (LM guide) (not shown).

The movable stage 62 is, for example, a plate-shaped member. The movable stage 62 is provided on both sides of the extrusion rod 60, for example. The movable stage 62 extends in the extending direction (first direction) of the injection plunger 42. The movable stage 62 has a function of advancing the injection plunger rod 42b.

A first pinion gear 62a and a second pinion gear 62b are fixed to the movable stage 62. The first pinion gear 62a is combined with the first rack 60a provided on the extrusion rod 60. The first pinion gear 62a meshes with the first rack 60a.

The second pinion gear 62b is combined with a second rack 64a provided on the fixed base 64. The second pinion gear 62b meshes with the second rack 64a.

The second pinion gear 62b rotates in conjunction with the first pinion gear 62a. The rotating shaft of the second pinion gear 62b and the rotating shaft of the first pinion gear 62a are connected by, for example, a drive transmission belt 62c. The second pinion gear 62b and the first pinion gear 62a rotate at the same rotation speed by being connected by, for example, a drive transmission belt 62c. As the drive transmission mechanism between the second pinion gear 62b and the first pinion gear 62a, a drive transmission chain can be used instead of the drive transmission belt 62c.

The number of teeth of the second pinion gear 62b is, for example, the same as the number of teeth of the first pinion gear 62a. The diameter of the second pinion gear 62b is, for example, the same as the diameter of the first pinion gear 62a. The rotation speed of the second pinion gear 62b is, for example, the same as the rotation speed of the first pinion gear 62a.

The movable stage 62 is movably supported with respect to the fixed base 64 by using, for example, a linear motion guide (LM guide) (not shown).

The fixing base 64 is, for example, a plate-shaped member. The fixing base 64 is provided on both sides of the extrusion rod 60 and the movable stage 62, for example. The fixing base 64 extends, for example, in the extending direction (first direction) of the injection plunger 42. The fixed base 64 has a function of movably supporting the movable stage 62.

A second rack 64a is provided on the fixed base 64. The second rack 64a is combined with the second pinion gear 62b. The second rack 64a meshes with the second pinion gear 62b.

The drive motor 66 has a function of moving the extrusion rod 60 and the movable stage 62. The drive motor 66 is, for example, a servo motor. For example, a servomotor is used as the drive motor 66, and the drive motor 66 is feedback-controlled based on the position information of the extrusion rod 60 detected by the position sensor 46.

The drive motor 66 applies a driving force to the rotating shaft of the first pinion gear 62a, for example. The drive motor 66 rotates, for example, the rotation shaft of the first pinion gear 62a. The rotation shaft of the drive motor 66 is connected to, for example, the rotation shaft of the first pinion gear 62a to rotate the first pinion gear 62a.

The drive motor 66, for example, applies a driving force to both rotating shafts of the two first pinion gears 62a. In this case, for example, two drive motors 66 are provided.

The drive motor 66 may, for example, apply a driving force to the rotating shaft of the second pinion gear 62b. The drive motor 66 rotates, for example, the rotation shaft of the second pinion gear 62b. The rotation shaft of the drive motor 66 is connected to, for example, the rotation shaft of the second pinion gear 62b to rotate the second pinion gear 62b.

The drive motor 66 applies a driving force to the rotation shafts of both the first pinion gear 62a and the second pinion gear 62b, for example. The drive motor 66 is connected to, for example, the rotation shafts of both the first pinion gear 62a and the second pinion gear 62b. In this case, for example, two drive motors 66 are provided.

The drive motor 66, for example, applies a driving force to both rotating shafts of the two second pinion gears 62b. In this case, for example, two drive motors 66 are provided.

The drive motor 66 may apply a driving force to all the rotating shafts of the two first pinion gears 62a and the two second pinion gears 62b, for example. In this case, for example, four drive motors 66 are provided.

The position sensor 46 has a function of detecting the position of the extrusion rod 60. The position sensor 46 has a function of detecting the position of the injection plunger 42. The position sensor 46 is, for example, an optical or magnetic linear encoder. By differentiating the position of the extrusion rod 60 detected by the position sensor 46, it is possible to detect the speed of the extrusion rod 60 and the injection plunger 42.

The position information of the extrusion rod 60 detected by the position sensor 46 is fed back to, for example, the drive of the drive motor 66.

Next, an example of the operation of the injection device of the first embodiment will be described. An example of the operation of the injection actuator 51 of the injection device 14 of the first embodiment will be described.

3 and 4 are schematic views illustrating the operation of the injection device of the molding machine of the first embodiment. 3 and 4 are schematic views of a main part of the injection device 14. 3 (a) and 4 (a) are top views, and FIGS. 3 (b) and 4 (b) are side views. 3 and 4 are schematic views including an injection actuator 51 of the injection device 14.

The injection actuator 51 of FIG. 2 is in a state before the start of the injection operation. In other words, in the injection actuator 51 of FIG. 2, the injection plunger 42 is in the most retracted state.

When starting the injection operation, for example, the drive motor 66 of the injection device 14 starts the operation by a command from the control device 32.

FIG. 3 shows a state in which the extrusion rod 60 is advancing. In other words, it indicates a state in which the injection plunger 42 is moving forward.

As shown in FIG. 3, the rotation of the drive motor 66 causes the first pinion gear 62a to rotate. At the same time, the second pinion gear 62b connected to the first pinion gear 62a by the drive transmission belt 62c also rotates in conjunction with the first pinion gear 62a.

The extrusion rod 60 advances relative to the movable stage 62 by the first rack and pinion mechanism composed of a combination of the first rack 60a and the first pinion gear 62a. Further, the movable stage 62 advances relative to the fixed base 64 by the second rack and pinion mechanism composed of the second rack 64a and the second pinion gear 62b.

Assuming that the relative movement distance of the movable stage 62 with respect to the fixed base 64 is d2, the relative movement distance of the extrusion rod 60 with respect to the movable stage 62 is also d2. Since the number of teeth of the second pinion gear 62b is the same as the number of teeth of the first pinion gear 62a, the relative movement distance of the movable stage 62 with respect to the fixed base 64 and the relative movement distance of the extrusion rod 60 with respect to the movable stage 62 Are the same. Therefore, assuming that the relative movement distance of the extrusion rod 60 with respect to the fixed base 64 is d1, d1 = 2 × d2.

By controlling the rotation of the drive motor 66, the extrusion rod 60 is advanced at a low speed for a predetermined time from the injection operation. For example, the speed of the extrusion rod 60 is, for example, less than 1 m / sec.

After a predetermined time has elapsed, the speed of the extrusion rod 60 is increased by increasing the rotation of the drive motor 66. The speed of the injection plunger 42 is set to, for example, 3 m / sec or more.

FIG. 4 shows a state in which the extrusion rod 60 is stopped. In other words, it indicates a state in which the injection plunger 42 is stopped. The injection actuator 51 of FIG. 4 is in the state in which the injection plunger 42 is most advanced. In this state, the filling of the molten metal into the cavity Ca formed by the fixed mold 18a and the movable mold 18b is completed.

High pressure is applied to the molten metal after the filling is completed in order to reduce the cavities caused by air that are caught during the filling of the molten metal and the cavities that are generated when the molten metal solidifies after the filling is completed. For example, the molten metal is pressurized by continuing to drive the drive motor 66 and continuously applying force to the extrusion rod 60.

After the pressurization of the molten metal is completed, the drive motor 66 is rotated in the reverse direction, so that the extrusion rod 60 retracts and returns to the state before the start of the injection operation shown in FIG.

Next, the operations and effects of the injection device and the molding machine of the first embodiment will be described.

In a molding machine such as a die casting machine, an injection device for injecting a material into a cavity in a mold is provided. From the viewpoints of improving the working environment, energy saving, space saving, and resource saving, it is desired to realize an electric injection device that does not use a hydraulic mechanism as much as possible. In particular, an electric injection device having practically sufficient high-speed characteristics and acceleration characteristics is desired.

The injection device 14 of the first embodiment is an electric injection device that operates by using the drive motor 66. The injection actuator 51 of the injection device 14 includes two rack and pinion mechanisms, that is, a structure in which a first rack and pinion mechanism and a second rack and pinion mechanism are combined.

As shown in FIGS. 3 and 4, in the injection actuator 51, by combining two rack and pinion mechanisms, the extrusion rod 60 per unit time is compared with the case where one rack and pinion mechanism is used. It is possible to double the amount of movement. Therefore, it is possible to double the speed of the extrusion rod 60 and double the acceleration of the extrusion rod 60.

Therefore, an electric injection device 14 having practically sufficient high-speed characteristics and acceleration characteristics is realized. Further, by using the injection device 14, a die casting machine 100 having practically sufficient high-speed characteristics and acceleration characteristics is realized.

From the viewpoint of improving the driving force of the injection device 14, it is preferable that the drive motor 66 is connected to the rotation shafts of both the first pinion gear 62a and the second pinion gear 62b, respectively.

As described above, according to the first embodiment, it is possible to realize an electric injection device and a molding machine capable of improving high-speed characteristics and acceleration characteristics.

(Second embodiment)
The injection device of the second embodiment is different from the injection device illustrated in the first embodiment in that the number of teeth of the second pinion gear is smaller than the number of teeth of the first pinion gear. In other words, it differs from the injection device illustrated in the first embodiment in that the number of teeth of the first pinion gear is larger than the number of teeth of the second pinion gear. Hereinafter, some descriptions of the contents overlapping with the first embodiment will be omitted.

The molding machine of the second embodiment includes the injection device.

FIG. 5 is a schematic view of a main part of the injection device of the molding machine of the second embodiment. 5 (a) is a top view and FIG. 5 (b) is a side view. FIG. 5 is a schematic view including an injection actuator 52 of the injection device 14. In the injection actuator 52 of FIG. 5, the injection plunger 42 is in the most retracted state.

FIG. 6 is a schematic view of a main part of the injection device of the molding machine of the second embodiment. 6 (a) is a top view and FIG. 6 (b) is a side view. FIG. 6 is a schematic view including an injection actuator 52 of the injection device 14. The injection actuator 52 of FIG. 6 is in the state in which the injection plunger 42 is most advanced.

The number of teeth of the second pinion gear 62b is smaller than the number of teeth of the first pinion gear 62a. In other words, the number of teeth of the first pinion gear 62a is larger than the number of teeth of the second pinion gear 62b. The number of teeth of the first pinion gear 62a is n times (n> 1) the number of teeth of the second pinion gear 62b.

The diameter of the second pinion gear 62b is, for example, smaller than the diameter of the first pinion gear 62a. The rotation speed of the second pinion gear 62b is, for example, the same as the rotation speed of the first pinion gear 62a.

Assuming that the relative movement distance of the movable stage 62 with respect to the fixed base 64 is d2, the relative movement distance of the extrusion rod 60 with respect to the movable stage 62 is n × d2. This is because the number of teeth of the first pinion gear 62a is n times the number of teeth of the second pinion gear 62b, so that the extrusion rod 60 can be moved with respect to the relative movement distance of the movable stage 62 with respect to the fixed base 64. This is because the relative movement distance with respect to the stage 62 is n times. Therefore, assuming that the relative movement distance of the extrusion rod 60 with respect to the fixed base 64 is d1, d1 = (1 + n) × d2.

For example, when n = 2, that is, when the number of teeth of the first pinion gear 62a is twice the number of teeth of the second pinion gear 62b, d1 = 3 × d2. The relative movement distance d2 of the extrusion rod 60 with respect to the fixed base 64 is three times the relative moving distance d1 of the movable stage 62 with respect to the fixed base 64.

For example, when n = 2, the injection actuator 52 combines two rack and pinion mechanisms to move the extrusion rod 60 per unit time as compared with the case of using one rack and pinion mechanism. Can be tripled. Therefore, it is possible to triple the speed of the extrusion rod 60 and triple the acceleration of the extrusion rod 60.

In the case of the injection actuator 51 of the first embodiment, it corresponds to n = 1. The larger n is, the more the speed and acceleration of the extrusion rod 60 can be improved.

From the viewpoint of improving the speed and acceleration of the extrusion rod 60, the number of teeth of the first pinion gear 62a is preferably twice or more, preferably three times or more the number of teeth of the second pinion gear 62b. More preferred.

As described above, according to the second embodiment, it is possible to realize an electric injection device and a molding machine capable of further improving high-speed characteristics and acceleration characteristics as compared with the first embodiment.

(Third Embodiment)
The injection device of the third embodiment further includes a support rod extending in the first direction and connected to the second member, the first motor applies a driving force to the support rod, and the support rod is first. It differs from the injection device of the first embodiment in that it is moved in the direction of. Hereinafter, some descriptions of the contents overlapping with the first embodiment will be omitted.

Further, the molding machine of the third embodiment includes the above-mentioned injection device.

FIG. 7 is a schematic view of a main part of the injection device of the molding machine of the third embodiment. 7 (a) is a top view and FIG. 7 (b) is a side view. FIG. 7 is a schematic view including an injection actuator 53 of the injection device 14. In the injection actuator 53 of FIG. 7, the injection plunger 42 is in the most retracted state.

FIG. 8 is a schematic view of a main part of the injection device of the molding machine of the third embodiment. 8 (a) is a top view and FIG. 8 (b) is a side view. FIG. 8 is a schematic view including an injection actuator 52 of the injection device 14. The injection actuator 53 of FIG. 8 is in the state in which the injection plunger 42 is most advanced.

The injection actuator 53 includes an extrusion rod 60 (first member), a movable stage 62 (second member), a fixing base 64 (third member), a drive motor 66 (first motor), a support rod 68, and a nut. 70 is provided. The extrusion rod 60 has a first rack 60a. The movable stage 62 has a first pinion gear 62a, a second pinion gear 62b, and a drive transmission belt 62c. The fixed base 64 has a second rack 64a.

The support rod 68 is a rod-shaped member. The support rod 68 is connected to the rear of the movable stage 62. The drive motor 66 applies a driving force to the support rod 68 to move the support rod 68 in the extending direction (first direction) of the injection plunger 42.

The support rod 68 is, for example, a screw shaft. The nut 70 is combined with the support rod 68. The support rod 68 and the nut 70 have a ball screw structure. The drive motor 66 rotates the nut 70 to move the support rod 68 in the extending direction of the injection plunger 42.

As the drive motor 66 rotates, the nut 70 rotates. As the nut 70 rotates, the movable stage 62 advances relative to the fixed base 64. A so-called ball screw mechanism is used to transmit the driving force from the drive motor 66 to the movable stage 62. The second pinion gear 62b is rotated by the second rack and pinion mechanism composed of the second rack 64a and the second pinion gear 62b.

The first pinion gear 62a connected to the second pinion gear 62b by the drive transmission belt 62c also rotates in conjunction with the second pinion gear 62b. The extrusion rod 60 advances relative to the movable stage 62 by the first rack and pinion mechanism composed of a combination of the first rack 60a and the first pinion gear 62a.

The number of teeth of the second pinion gear 62b is, for example, the same as the number of teeth of the first pinion gear 62a. The diameter of the second pinion gear 62b is, for example, the same as the diameter of the first pinion gear 62a. The rotation speed of the second pinion gear 62b is, for example, the same as the rotation speed of the first pinion gear 62a.

Assuming that the relative movement distance of the movable stage 62 with respect to the fixed base 64 is d2, the relative movement distance of the extrusion rod 60 with respect to the movable stage 62 is also d2. Since the number of teeth of the second pinion gear 62b is the same as the number of teeth of the first pinion gear 62a, the relative movement distance of the movable stage 62 with respect to the fixed base 64 and the relative movement distance of the extrusion rod 60 with respect to the movable stage 62 Are the same. Therefore, assuming that the relative movement distance of the extrusion rod 60 with respect to the fixed base 64 is d1, d1 = 2 × d2.

In the injection actuator 53 of the third embodiment, the drive motor 66 is separated from the movable stage 62. Therefore, the weight of the movable stage 62 can be reduced. Therefore, as compared with the first embodiment, it is possible to further improve the high-speed characteristics and the acceleration characteristics.

As described above, according to the third embodiment, it is possible to realize an electric injection device and a molding machine capable of further improving high-speed characteristics and acceleration characteristics as compared with the first embodiment.

(Fourth Embodiment)
The injection device of the fourth embodiment further includes an accumulator fixed to the second member, the first member having a piston rod and a piston connected to the piston rod, and a second member. The member is different from the injection device of the first embodiment in that it slidably accommodates the piston, has a cylinder including a head side chamber behind the piston, and the accumulator supplies liquid to the head side chamber. Hereinafter, some descriptions of the contents overlapping with the first embodiment will be omitted.

Further, the molding machine of the fourth embodiment includes the above-mentioned injection device.

9 and 10 are schematic views of a main part of the injection device of the molding machine of the fourth embodiment. 9 and 10 are schematic views including an injection actuator 54 of the injection device 14. 9 (a) is a top view and FIG. 9 (b) is a side view. 10 (a) is a partial cross-sectional view of FIG. 9 (a). 10 (b) is a partial cross-sectional view of FIG. 9 (b). In the injection actuator 54 of FIGS. 9 and 10, the injection plunger 42 is in the most retracted state.

11 and 12 are schematic views of a main part of the injection device of the molding machine of the fourth embodiment. 11 and 12 are schematic views including an injection actuator 54 of the injection device 14. 11 (a) is a top view and FIG. 11 (b) is a side view. 12 (a) is a partial cross-sectional view of FIG. 11 (a). 12 (b) is a partial cross-sectional view of FIG. 11 (b). The injection actuator 54 of FIGS. 11 and 12 is in a state in which the injection plunger 42 is most advanced.

The injection actuator 54 includes an extrusion rod 60 (first member), a movable stage 62 (second member), a fixing base 64 (third member), a drive motor 66 (first motor), a support rod 68, and a nut. It includes 70, an accumulator 72, and a valve 74.

The extrusion rod 60 has a first rack 60a, a piston rod 60b, and a piston 60c. The movable stage 62 has a first pinion gear 62a, a second pinion gear 62b, a drive transmission belt 62c, a cylinder 62d, and a head side chamber 62e. The fixed base 64 has a second rack 64a.

The piston rod 60b is a round bar-shaped member. For example, a first rack 60a is provided on the side surface of the piston rod 60b.

The piston 60c is connected to the piston rod 60b. The piston 60c is slidably provided in the cylinder 62d.

The cylinder 62d has a head side chamber 62e. The head side chamber 62e is provided behind the piston 60c, that is, on the side opposite to the piston rod 60b with respect to the piston 60c. For example, hydraulic oil (liquid) is stored in the head side chamber 62e.

The accumulator 72 is fixed to the movable stage 62. The accumulator 72 has a function of supplying hydraulic oil to the head side chamber 62e.

The accumulator 72 stores energy using a high-pressure filled gas and momentarily releases the energy to increase the flow rate of hydraulic oil. By providing the accumulator 72, the injection actuator 54 can be operated at a higher speed, and the injection actuator 54 can generate a higher pressure.

The valve 74 is provided between the accumulator 72 and the cylinder 62d. The valve 74 is provided between the accumulator 72 and the head side chamber 62e.

The valve 74 controls the flow of hydraulic oil flowing between the accumulator 72 and the head side chamber 62e. The valve 74 controls the supply and stop of hydraulic oil from the accumulator 72 to the head side chamber 62e.

The valve 74 is, for example, a servo valve. The servo valve is an electromagnetic direction switching valve that switches the flow path using electromagnetic force. The servo valve has high response performance to the input signal. For example, a servo valve is used for the valve 74, and the valve 74 is feedback-controlled based on the position information of the extrusion rod 60 detected by the position sensor 46.

Next, an example of the operation of the injection device of the fourth embodiment will be described. An example of the operation of the injection actuator 54 of the injection device 14 of the fourth embodiment will be described.

The injection actuator 54 of FIGS. 9 and 10 is in a state before the start of the injection operation. In the injection actuator 54 of FIGS. 9 and 10, the injection plunger 42 is in the most retracted state.

When starting the injection operation, for example, the drive motor 66 of the injection device 14 starts the operation by a command from the control device 32. The nut 70 is rotated by the drive motor 66, and the support rod 68 is advanced so that the movable stage 62 advances with respect to the fixed base 64.

As the movable stage 62 advances, the first pinion gear 62a connected to the second pinion gear 62b rotates. Therefore, the extrusion rod 60 advances relative to the movable stage 62.

Further, in response to a command from the control device 32, the valve 74 is opened, and hydraulic oil is supplied from the accumulator 72 to the head side chamber 62e. The pressure of the hydraulic oil pushes the piston 60c and advances the extrusion rod 60.

As the extrusion rod 60 advances, the second pinion gear 62b connected to the first pinion gear 62a rotates. Therefore, the movable stage 62 advances with respect to the fixed base 64.

A driving force due to the pressure of the hydraulic oil generated by the accumulator 72 is directly applied to the extrusion rod 60. At the same time, the driving force of the drive motor 66 is indirectly applied to the extrusion rod 60 by the first rack and pinion mechanism and the second rack and pinion mechanism.

The movement of the extrusion rod 60 is controlled by using both the driving force of the accumulator 72 and the driving force of the drive motor 66.

Assuming that the relative movement distance of the movable stage 62 with respect to the fixed base 64 is d2, the relative movement distance of the extrusion rod 60 with respect to the movable stage 62 is also d2. Since the number of teeth of the second pinion gear 62b is the same as the number of teeth of the first pinion gear 62a, the relative movement distance of the movable stage 62 with respect to the fixed base 64 and the relative movement distance of the extrusion rod 60 with respect to the movable stage 62 Are the same. Therefore, assuming that the relative movement distance of the extrusion rod 60 with respect to the fixed base 64 is d1, d1 = 2 × d2.

For example, by controlling the rotation of the drive motor 66 and the amount of hydraulic oil supplied from the accumulator 72 to the head side chamber 62e, the extrusion rod 60 is advanced at a low speed for a predetermined time from the injection operation. For example, the speed of the extrusion rod 60 is, for example, less than 1 m / sec.

After a predetermined time has elapsed, the speed of the extrusion rod 60 is increased, for example, by increasing the rotation of the drive motor 66. Further, for example, by increasing the supply amount of hydraulic oil from the accumulator 72 to the head side chamber 62e, the speed of the injection plunger 42 is set to, for example, 1 m / sec or more.

11 and 12 show a state in which the extrusion rod 60 is stopped. In other words, it indicates a state in which the injection plunger 42 is stopped. The injection actuator 54 of FIGS. 11 and 12 is in a state in which the injection plunger 42 is most advanced. In this state, the filling of the molten metal into the cavity Ca formed by the fixed mold 18a and the movable mold 18b is completed.

High pressure is applied to the molten metal after the filling is completed in order to reduce the cavities caused by air that are caught during the filling of the molten metal and the cavities that are generated when the molten metal solidifies after the filling is completed. For example, the molten metal is pressurized by continuing to drive the drive motor 66 and continuously applying force to the extrusion rod 60. Further, for example, the molten metal is pressurized by continuously applying pressure to the hydraulic oil with the accumulator 72.

After the pressurization of the molten metal is completed, the drive motor 66 is rotated in the reverse direction to retract the extrusion rod 60 and return to the state before the start of the injection operation shown in FIGS. 9 and 10. At this time, the hydraulic oil returns to the accumulator 72. When the hydraulic oil returns to the accumulator 72, energy is stored in the accumulator 72 using the high-pressure filled gas.

The injection actuator 54 of the fourth embodiment uses a drive motor 66 and an accumulator 72 as a source of driving force. Therefore, the operation of the injection device 14 can be controlled with high accuracy. Therefore, it is possible to further improve the high-speed characteristics and the acceleration characteristics. Further, by using the hydraulic pressure as the driving force, it is possible to generate a higher pressure. Further, the load of the drive motor 66 is reduced by using the hydraulic pressure as the driving force.

As described above, according to the fourth embodiment, it is possible to realize an electric injection device and a molding machine capable of further improving high-speed characteristics and acceleration characteristics as compared with the first embodiment. Moreover, it becomes possible to generate a higher pressure. In addition, the load on the motor is reduced.

(Fifth Embodiment)
The injection device of the fifth embodiment further includes a second motor and a pressurizing member that pressurizes the liquid supplied to the head side chamber, and the second motor applies a driving force to the pressurizing member. , Different from the injection device of the fourth embodiment. Hereinafter, some descriptions of the contents overlapping with the fourth embodiment will be omitted.

Further, the molding machine of the fifth embodiment includes the above-mentioned injection device.

13 and 14 are schematic views of a main part of the injection device of the molding machine of the fifth embodiment. 13 and 14 are schematic views including an injection actuator 55 of the injection device 14. 13 (a) is a top view and FIG. 13 (b) is a side view. 14 (a) is a partial cross-sectional view of FIG. 13 (a). 14 (b) is a partial cross-sectional view of FIG. 13 (b). In the injection actuator 55 of FIGS. 13 and 14, the injection plunger 42 is in the most retracted state.

15 and 16 are schematic views of a main part of the injection device of the molding machine of the fifth embodiment. 15 and 16 are schematic views including an injection actuator 54 of the injection device 14. 15 (a) is a top view and FIG. 15 (b) is a side view. 16 (a) is a partial cross-sectional view of FIG. 15 (a). 16 (b) is a partial cross-sectional view of FIG. 15 (b). In the injection actuator 55 of FIGS. 15 and 16, the injection plunger 42 is in the most advanced state.

The injection actuator 55 includes an extrusion rod 60 (first member), a movable stage 62 (second member), a fixing base 64 (third member), a drive motor 66 (first motor), a support rod 68, and a nut. It includes 70, an accumulator 72, a valve 74, a pressurizing motor 76 (second motor), and a pressurizing plunger 78 (pressurizing member).

The pressurizing plunger 78 has a function of pressurizing the hydraulic oil in the head side chamber 62e. The pressurizing plunger 78 is slidably provided with respect to the opening formed in the movable stage 62.

The pressurizing motor 76 has a function of driving the pressurizing plunger 78. The pressurizing motor 76 is fixed to the movable stage 62. For example, a ball screw mechanism is used to transmit the driving force from the pressurizing motor 76 to the pressurizing plunger 78.

High pressure is applied to the molten metal after the filling is completed in order to reduce the cavities caused by air that are caught during the filling of the molten metal and the cavities that are generated when the molten metal solidifies after the filling is completed. In the injection device 14 of the fifth embodiment, the molten metal is pressurized by continuously applying pressure to the hydraulic oil by using the pressurizing motor 76 and the pressurizing plunger 78. Therefore, the pressurizing characteristics are improved as compared with the injection device 14 of the fourth embodiment.

As described above, according to the fifth embodiment, it is possible to realize an electric injection device and a molding machine capable of improving high-speed characteristics and acceleration characteristics as in the fourth embodiment. Further, it is possible to realize an electric injection device and a molding machine having particularly improved pressurizing characteristics.

(Sixth Embodiment)
In the injection device of the sixth embodiment, the connecting portion connects the rear end of the injection member and the front end of the piston rod, and the connecting portion is a liquid between the rear end of the injection member and the front end of the piston rod. The injection device of the fifth embodiment is provided with a case forming a surge pressure absorption chamber filled with the above, and a communication furnace for communicating the head side chamber and the surge pressure absorption chamber is formed in the piston rod and the piston. Is different. Hereinafter, some descriptions of the contents overlapping with the fifth embodiment will be omitted.

Further, the molding machine of the sixth embodiment includes the above-mentioned injection device.

FIG. 17 is a schematic view of a main part of the injection device of the molding machine of the sixth embodiment. FIG. 17 is a cross-sectional view of a part of a main part of the injection device corresponding to FIG. 14 of the fifth embodiment. In the injection actuator of FIG. 17, the injection plunger 42 is in the most retracted state.

The coupling 44 of the injection device 14 connects the rear end 42c of the injection plunger rod 42b and the front end 60d of the piston rod 60b.

The coupling 44 has a case 44a. The case 44a includes a surge pressure absorbing chamber 44b. The surge pressure absorption chamber 44b is located between the rear end 42c of the injection plunger rod 42b and the front end 60d of the piston rod 60b. The surge pressure absorption chamber 44b is filled with hydraulic oil.

Further, the piston rod 60b and the piston 60c are formed with a communication passage 60e for communicating the head side chamber 62e and the surge pressure absorption chamber 44b. The communication passage 60e allows the hydraulic oil to move between the head side chamber 62e and the surge pressure absorption chamber 44b.

In the injection device, it is known that a high pressure is instantaneously generated when the filling of the molten metal into the mold is completed. That is, it is known that so-called surge pressure is generated. If this surge pressure is large, for example, the impact applied to a drive mechanism such as a motor that drives an injection device becomes large, and the drive mechanism may break down.

In the injection device 14 of the sixth embodiment, the surge pressure absorption chamber 44b is filled with hydraulic oil. When the filling of the molten metal into the mold is completed, the volume of the surge pressure absorption chamber 44b between the rear end 42c of the injection plunger rod 42b and the front end 60d of the piston rod 60b is reduced. Therefore, the surge pressure is reduced, and the impact applied to the piston rod 60b is reduced. Therefore, the impact applied to the drive mechanism such as the drive motor 66, the first rack and pinion mechanism, and the second rack and pinion mechanism can be reduced, and the failure of the drive mechanism can be suppressed.

As described above, according to the sixth embodiment, an electric injection device and a molding machine capable of improving high-speed characteristics and acceleration characteristics can be realized as in the fifth embodiment. Further, an electric injection device and a molding machine having improved pressurizing characteristics can be realized. In addition, an electric injection device and a molding machine capable of suppressing a failure of the drive mechanism can be realized.

The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. Although the description is omitted for parts of the injection device, molding machine, etc. that are not directly required for the description of the present invention, the required elements related to the injection device, molding machine, etc. can be appropriately selected and used.

In the first to sixth embodiments, a die casting machine has been described as an example of a molding machine, but the present invention can also be applied to an injection molding machine or the like.

Further, in the first to sixth embodiments, the case where the rack and pinion mechanisms are provided on both sides of the extrusion rod 60 has been described as an example. For example, the rack and pinion mechanisms are provided above and below the extrusion rod 60. It is also possible to have a configuration provided.

Further, in the first to sixth embodiments, a case where a two-stage rack and pinion mechanism is applied to improve high-speed characteristics and acceleration characteristics has been described as an example, but three or more stages of rack and pinions have been described. It is also possible to apply the mechanism to further improve the high speed characteristics and acceleration characteristics.

Further, in the first to sixth embodiments, the case where the number of teeth of the second pinion gear 62b is equal to or less than the number of teeth of the first pinion gear 62a has been described as an example, but the second pinion gear 62b It is also possible to increase the number of teeth to be larger than the number of teeth of the first pinion gear 62a.

In addition, all injection devices and molding machines having the elements of the present invention and which can be appropriately redesigned by those skilled in the art are included in the scope of the present invention. The scope of the present invention is defined by the scope of claims and the scope of their equivalents.

10 Mold clamping device 12 Extruding device 14 Injection device 18 Mold 18a Fixed mold 18b Movable mold 20 Control unit 22 Base 24 Fixed die plate 26 Movable die plate 28 Link housing 30 Tie bar 32 Control device 34 Input device 36 Display device 40 Injection Sleeve 42 Injection plunger (injection member)
42a Injection plunger tip 42b Injection plunger rod 42c Rear end 44 Coupling (connecting part)
44a Case 44b Surge pressure absorption chamber 46 Position sensor 51 Injection actuator 52 Injection actuator 53 Injection actuator 54 Injection actuator 55 Injection actuator 60 Extrusion rod (first member)
60a First rack 60b Piston rod 60c Piston 60d Front end 60e Continuous passage 62 Movable stage (second member)
62a First pinion gear 62b Second pinion gear 62c Drive transmission belt 62d Cylinder 62e Head side chamber 64 Fixing base (third member)
64a Second rack 66 drive motor (first motor)
68 Support rod 70 Nut 72 Accumulator 74 Valve 76 Pressurization motor (second motor)
78 Pressurized plunger (pressurized member)
100 Die casting machine (molding machine)
Ca cavity

Claims (10)

A first member that injects material into a mold of a molding machine and can be connected to an injection member that extends in the first direction, has a first rack, and extends in the first direction.
A second member having a first pinion gear combined with the first rack, a second pinion gear that rotates in conjunction with the first pinion gear, and a second member extending in the first direction. ,
A third member having a second rack combined with the second pinion gear, and
A first motor that moves the first member and the second member in the first direction, and
An injection device characterized by: The injection device according to claim 1, wherein the number of teeth of the second pinion gear is equal to or less than the number of teeth of the first pinion gear. The injection device according to claim 1 or 2, wherein the first motor applies a driving force to at least one of the rotation shafts of the first pinion gear and the second pinion gear. A support rod extending in the first direction and connected to the second member is further provided.
The injection device according to claim 1 or 2, wherein the first motor applies a driving force to the support rod to move the support rod in the first direction. Further provided with a nut combined with the support rod,
The support rod is a screw shaft and
The injection device according to claim 4, wherein the first motor rotates the nut to move the support rod in the first direction. An accumulator fixed to the second member is further provided.
The first member includes a piston rod and a piston connected to the piston rod.
The second member has a cylinder that slidably accommodates the piston and includes a head concubine behind the piston.
The injection device according to any one of claims 1 to 5, wherein the accumulator supplies a liquid to the head side chamber. With the second motor
A pressurizing member that pressurizes the liquid supplied to the head side chamber is further provided.
The injection device according to claim 6, wherein the second motor applies a driving force to the pressurizing member. Further provided with a connecting portion for connecting the rear end of the injection member and the front end of the piston rod.
The connecting portion has a case forming a surge pressure absorption chamber filled with the liquid between the rear end of the injection member and the front end of the piston rod.
The injection device according to claim 6 or 7, wherein a communication passage connecting the head side chamber and the surge pressure absorption chamber is formed in the piston rod and the piston. The injection device according to any one of claims 1 to 8, wherein the number of teeth of the first pinion gear is at least twice the number of teeth of the second pinion gear. A molding machine comprising the injection device according to any one of claims 1 to 9.

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