TWI481492B - Injection molding machine - Google Patents

Description

Injection molding machine

The present invention relates to an injection molding machine.

The injection molding machine produces a molded article by filling and solidifying the molten resin in the cavity space of the mold device. The mold device is composed of a fixed mold and a movable mold, and a cavity space is formed between the fixed mold and the movable mold during mold clamping. The mold closing, mold clamping, and mold opening of the mold apparatus are performed by a mold clamping device. As the mold clamping device, a linear motor is used for the mold opening and closing operation, and an electromagnet is used for the mold clamping operation (see, for example, Patent Document 1).

(previous technical literature) (Patent Literature)

Patent Document 1: International Publication No. 05/090052

In the past, it was required to reduce the power consumption of the linear motor. Linear motors are more susceptible to power consumption when accelerating or decelerating than when traveling at a constant speed.

The present invention has been made in view of the above problems, and an object thereof is to provide an injection molding machine capable of reducing power consumption of a linear motor.

In order to solve the above problems, an injection molding method according to an aspect of the present invention The present invention includes a linear motor including a movable member and a fixed member and performing a mold opening and closing operation, and a speed reducing mechanism that absorbs at least a part of kinetic energy of the movable member that moves in a predetermined direction. The aforementioned movable member is decelerated. Further, an injection molding machine according to another aspect of the present invention includes: a linear motor including a movable member and a fixing member and performing a mold opening and closing operation; and an acceleration mechanism including an elastic body and The elastic restoring force of the elastic body accelerates the aforementioned movable member.

According to the present invention, an injection molding machine capable of reducing power consumption of a linear motor is provided.

In the following, the embodiments for carrying out the invention will be described with reference to the accompanying drawings. In addition, the moving direction of the movable platen when the mold is closed is set to the front, and the moving direction of the movable platen when the mold is opened is set to the rear.

[First Embodiment]

Fig. 1 is a view showing a state in which the injection molding machine according to the first embodiment of the present invention is closed. Fig. 2 is a view showing a state at the time of completion of mold opening by the injection molding machine according to the first embodiment of the present invention.

In the figure, 10 is an injection molding machine, Fr is a frame of the injection molding machine 10, Gd is a guide composed of two rails laid on the frame Fr, and 11 is a fixed platen. The fixed platen 11 can be disposed on the position adjustment base Ba which is movable along the guide member Gd extending in the mold opening and closing direction (the horizontal direction in the drawing). In addition, the fixed platen 11 can also be placed on the frame Fr.

The movable platen 12 is disposed opposite to the fixed platen 11. The movable platen 12 is fixed to the movable base Bb, and the movable base Bb is movable on the guide Gd. Thereby, the movable platen 12 can be moved in the mold opening and closing direction with respect to the fixed platen 11.

The rear platen 13 is disposed at a predetermined interval from the fixed platen 11 in parallel with the fixed platen 11. The rear platen 13 is fixed to the frame Fr via the leg portion 13a.

The four tie rods 14 (only two of the four tie rods 14 are shown in the drawing) are spanned between the fixed pressure plate 11 and the rear pressure plate 13 . The fixed platen 11 is fixed to the rear platen 13 via a tie rod 14. The movable platen 12 is disposed to move forward and backward along the tie rod 14. A portion of the movable platen 12 corresponding to the tie bar 14 is formed with a guide hole (not shown) for piercing the tie bar 14. In addition, a notch portion may be formed instead of the via hole.

The distal end portion (the right end portion in the drawing) of the tie rod 14 is formed with a screw portion (not shown), and the nut n1 is screwed and fastened to the screw portion, whereby the distal end portion of the tie rod 14 is fixed to the fixed pressure plate 11. The rear end of the tie rod 14 is fixed to the rear pressure Board 13.

A fixed die 15 is attached to the fixed platen 11, and a movable die 16 is attached to the movable platen 12. The fixed die 15 and the movable die 16 are contact-separated with the advancement and retreat of the movable platen 12, thereby performing mold closing, mold clamping, and mold opening. Further, as the mold clamping is performed, a cavity space (not shown) is formed between the fixed mold 15 and the movable mold 16, and the molten resin is filled in the cavity space. The mold device 19 is constituted by the fixed mold 15 and the movable mold 16.

The adsorption plate 22 is disposed in parallel with the movable platen 12. The suction plate 22 is fixed to the slide base Sb via a mounting plate 27, and the slide base Sb is movable on the guide Gd. Thereby, the suction plate 22 becomes retractable more rearward than the rear platen 13. The adsorption plate 22 may be formed of a soft magnetic material. Further, the mounting plate 27 may not be provided, and in this case, the suction plate 22 is directly fixed to the sliding base Sb.

The rod 39 is disposed to be coupled to the suction plate 22 at the rear end portion and coupled to the movable platen 12 at the front end portion. Therefore, the rod 39 advances with the advancement of the suction plate 22 at the time of mold closing, and advances the movable platen 12, and retreats with the retraction of the suction plate 22 at the time of mold opening, and the movable platen 12 is retracted. Therefore, a rod hole 41 for penetrating the rod 39 is formed in the central portion of the rear platen 13.

The linear motor 28 is a mold opening and closing drive unit for moving the movable platen 12 forward and backward, and is disposed, for example, between the suction plate 22 coupled to the movable platen 12 and the frame Fr. Further, the linear motor 28 may be disposed between the movable platen 12 and the frame Fr.

The linear motor 28 includes a fixing member 29 and a movable member 31. The fixing member 29 is formed to be parallel to the guiding member Gd and to the sliding base Sb on the frame Fr The range of motion corresponds. The movable member 31 is formed to face the fixing member 29 at a lower end of the sliding base Sb and over a predetermined range.

The mover 31 includes a magnetic core 34 and a coil 35. The magnetic core 34 has a plurality of magnetic pole teeth 33 that protrude toward the fixing member 29. The plurality of magnetic pole teeth 33 are arranged at a predetermined pitch in a direction parallel to the opening and closing direction of the mold. The coil 35 is wound around each of the magnetic pole teeth 33.

The fixing member 29 includes a magnetic core (not shown) and a plurality of permanent magnets (not shown) provided on the magnetic core. The plurality of permanent magnets are arranged at a predetermined pitch in a direction parallel to the opening and closing direction of the mold, and the magnetic poles on the side of the movable member 31 are alternately magnetized by the N pole and the S pole.

When a predetermined current is supplied to the coil 35 of the movable member 31, the movable member 31 advances and retreats by the interaction of the magnetic field formed by the current flowing through the coil 35 and the magnetic field formed by the permanent magnet. Accordingly, the adsorption plate 22 and the movable platen 12 are advanced and retracted to perform mold closing and mold opening. The linear motor 28 performs feedback control based on the detection result of the position sensor 53 that detects the position of the movable member 31 so that the position of the movable member 31 becomes the target value.

Further, in the present embodiment, a permanent magnet is disposed in the fixing member 29, and the coil 35 is disposed in the movable member 31. However, a coil may be disposed in the fixing member, and a permanent magnet may be disposed in the movable member. At this time, since the coil does not move with the driving of the linear motor 28, the wiring for supplying electric power to the coil can be easily performed.

The electromagnet unit 37 generates an adsorption force between the rear platen 13 and the adsorption plate 22. This suction force is transmitted to the movable platen 12 via the rod 39, and a mold clamping force is generated between the movable platen 12 and the fixed platen 11.

The electromagnet unit 37 is composed of an electromagnet 49 formed on the side of the rear platen 13 and an adsorption portion 51 formed on the side of the adsorption plate 22. The adsorption portion 51 is formed at a predetermined portion of the adsorption surface (front end surface) of the adsorption plate 22, for example, a portion of the adsorption plate 22 that surrounds the rod 39 and faces the electromagnet 49. Further, a groove 45 for accommodating the coil 48 of the electromagnet 49 is formed around a predetermined portion of the suction surface (rear end portion) of the rear platen 13, for example, around the rod 39. The magnetic core 46 is formed on the inner side of the groove 45. The coil 48 is wound around the magnetic core 46. A yoke 47 is formed in a portion other than the magnetic core 46 in the rear platen 13.

Further, in the present embodiment, the electromagnet 49 is formed separately from the rear platen 13, and the adsorption portion 51 is formed separately from the adsorption plate 22, but the electromagnet may be formed as a part of the rear platen 13, and the adsorption portion may be formed as A portion of the adsorption plate 22. Further, the electromagnet and the adsorption portion may be arranged in reverse. For example, the electromagnet 49 can be provided on the side of the adsorption plate 22, and the adsorption portion 51 can be provided on the side of the rear platen 13. Further, the number of the coils 48 of the electromagnet 49 may be plural.

In the electromagnet unit 37, when a current is supplied to the coil 48, the electromagnet 49 is driven to adsorb the adsorption portion 51, and the mold clamping force can be generated. The electromagnet unit 37 performs feedback control based on the detection result of the mold clamping force sensor 55 that detects the mold clamping force so that the mold clamping force becomes the target value. The mold clamping force sensor 55 may also be, for example, a strain sensor that detects the strain (elongation amount) of the tie rod 14 that is elongated in accordance with the mold clamping force. Further, as the mold clamping force sensor 55, for example, a load sensor that detects a load sensor or the like applied to the load of the rod 39 and a magnetic sensor that detects a magnetic field of the electromagnet 49 can be used, and the mold clamping force is sensed. The type of the device 55 can be varied.

The control unit 60 includes, for example, a CPU, a memory, and the like, and controls the operation of the line motor 28 and the electromagnet 49 by processing the control program recorded in the memory by the CPU.

Next, the operation of the injection molding machine 10 having the above configuration will be described. The various operations of the injection molding machine 10 are performed under the control of the control unit 60.

The control unit 60 controls the mold closing process. When the control unit 60 supplies a predetermined current to the coil 35 of the linear motor 28 in the state of the second drawing (the state at the time of completion of the mold opening), the movable member 31 starts moving forward from the backward limit position. After the movable member 31 is accelerated to the set speed, it moves toward the front at the set speed, and then is decelerated to stop at the forward limit position. At this time, the fixed mold 15 abuts against the movable mold 16 to end the mold closing process. At this time, a gap δ is formed between the rear platen 13 and the adsorption plate 22, that is, between the electromagnet 49 and the adsorption portion 51. In addition, the force required to close the mold is very small compared to the mold clamping force.

Next, the control unit 60 controls the mold clamping process. The control unit 60 supplies a direct current to the coil 48 of the electromagnet 49 in the state of Fig. 1 (the state at the end of the mold closing). Thus, a magnetic field is generated in the coil 48 by the direct current flowing through the coil 48, and the magnetic core 46 is magnetized, and the magnetic field is strengthened. Further, an adsorption force is generated between the electromagnet 49 opposed to the predetermined gap and the adsorption portion 51, and the adsorption force is transmitted to the movable platen 12 via the rod 39, thereby generating a mold clamping force between the movable platen 12 and the fixed platen 11. . The molten resin is filled in the cavity space of the mold device 19 in the mold clamping state, and is cooled and solidified to be a molded article.

Next, after the control unit 60 stops supplying electric power to the coil 48 of the electromagnet 49, the control unit 60 controls the mold opening process. When the control unit 60 supplies a predetermined current to the coil 35 of the linear motor 28, the movable platen 12 starts moving toward the rear from the forward limit position. After the movable member 31 is accelerated to the set speed, it moves toward the rear at the set speed, and then is decelerated to stop at the reverse limit position, thereby ending the mold opening process. After the mold opening process is completed, the molded article is obtained by ejecting the molded article from the movable mold 16 by an ejector means not shown.

Fig. 3 is an explanatory view of a speed reduction mechanism of the injection molding machine according to the first embodiment. Fig. 3(a) shows a state in which the movable member moving in the mold opening direction is traveling at a constant speed, and Fig. 3(b) shows a state in which the movable member is decelerated.

In order to reduce the power consumption of the linear motor 28, the injection molding machine 10 includes a speed reduction mechanism 70 that absorbs at least a part of the kinetic energy of the movable member 31 that moves in the mold opening direction (the left direction in the drawing) to decelerate the movable member 31. For example, as shown in Fig. 3, the speed reduction mechanism 70 is constituted by a spring 71 or the like as an elastic body.

Further, when the speed reducing mechanism 70 decelerates the movable member 31, it can absorb not only the kinetic energy of the movable member 31 but also the member that moves together with the movable member 31 (for example, the sliding base Sb, the suction plate 22, the rod 39, the movable platen 12, and The kinetic energy of the movable mold 16).

The spring 71 is, for example, a coil spring, and the expansion and contraction direction of the spring 71 is parallel to the mold opening and closing direction. The spring 71 is disposed between the slide base Sb and the fixed member 77 as the first movable member that moves together with the mover 31, and is attached only to either one of the slide base Sb and the fixed member 77 (fixed in FIG. 3) Member 77). The fixing member 77 is disposed further behind the sliding base Sb Square, and fixed with respect to the frame Fr.

When a predetermined current is supplied to the coil 35 of the linear motor 28 in a state where the mold clamping process is completed, the mover 31 starts moving toward the rear from the forward limit position, and starts mold opening. After the movable member 31 is accelerated to the set speed, it moves toward the rear at the set speed. At this time, as shown in Fig. 3(a), the slide base Sb is not in contact with the spring 71, and the spring 71 is not elastically deformed in a natural state.

Next, when the slide base Sb comes into contact with the spring 71, the spring 71 is sandwiched between the slide base Sb and the fixing member 77 as shown in Fig. 3(b), and is elastically contracted. Thereby, at least a part of the kinetic energy of the sliding base Sb or the movable member 31 is converted into the elastic energy of the spring 71, and the sliding base Sb or the movable member 31 is decelerated. Therefore, the current flowing to the coil 35 of the linear motor 28 for the deceleration of the movable member 31 can be reduced. When the mover 31 is decelerated, the energization to the coil 35 of the linear motor 28 can be cut off.

Then, the movable member 31 is stopped at the retreat limit position to end the mold opening process. At this time, the spring 71 becomes a super-contracted state, and the elastic restoring force of the spring 71 also becomes the highest. The slide base Sb, the mover 31, and the movable mold 16 are biased in the mold closing direction (the right direction in the drawing) by the elastic restoring force of the spring 71.

After the mold opening process is completed, during the ejection of the molded article from the movable mold 16 by the ejector, the control unit 60 supplies a current to the coil 35 of the linear motor 28 to stop the movable member 31 in order to stop the movable mold 16. The time for stopping the movable member 31 is short, and the mold closing process is started immediately after the molded article is pushed out.

At the beginning of the mold closing process, the movable member is made by the elastic restoring force of the spring 71 31 accelerates toward the closed mode. Therefore, the current flowing to the coil 35 of the linear motor 28 for the acceleration of the movable member 31 can be reduced. While the length of the spring 71 is restored to the natural length, the energization of the coil 35 to the linear motor 28 can be cut off.

As described above, according to the present embodiment, when the movable member 31 is folded back at the retreat restricting position, the deceleration and acceleration of the movable member 31 are performed by the speed reducing mechanism 70, so that the power consumption of the linear motor 28 can be reduced. Therefore, the electric energy that can be reduced by the speed reduction mechanism 70 is more than the electric energy required to stop the movable member 31, and the power can be saved as a whole. In order to improve the power saving efficiency, the spring rate of the spring 71 is optimized.

The spring 71 is attached only to either one of the fixed member 77 and the slide base Sb, so that the spring 71 is elastically deformed to decelerate or accelerate the movable member 31 only when the movable member 31 is located near the retreat limit. Thereby, the constant speed travel of the movable member 31 is stabilized.

Further, in the present embodiment, the slide base Sb is used as the first movable member, but for example, the suction plate 22 or the movable platen 12 may be used.

Further, although the spring of the present embodiment is disposed between the first movable member and the fixed member 77, it may be disposed between the movable member 31 and the fixed member 77.

Further, in the present embodiment, the coil spring is used as the spring 71. However, an air spring may be used, and the structure of the spring is not particularly limited. In addition, instead of the spring 71, rubber may be used as the elastic body.

[Second Embodiment]

The spring 71 of the above-described first embodiment is disposed between the movable member 31 or the first movable member and the fixed member 77 that move together with the movable member 31, and is attached only to either one.

On the other hand, the spring of the present embodiment differs in that it is disposed between the second movable member and the movable member 31 that move together with the movable mold 16 and is coupled to each other. Hereinafter, the description will be centered on differences.

Fig. 4 is an explanatory view of a speed reduction mechanism of the injection molding machine according to the second embodiment. Fig. 4(a) shows the state at the end of the mold opening, and Fig. 4(b) shows the state when the mover is decelerated after the mold opening is completed.

The speed reduction mechanism 170 absorbs at least a part of the kinetic energy of the movable member 31 moving in the mold opening direction (the left direction in the drawing) to decelerate the movable member 31. The speed reduction mechanism 170 is constituted by a spring 171 or the like.

The spring 171 is, for example, a coil spring, and the expansion and contraction direction of the spring 171 is parallel to the mold opening and closing direction. The spring 171 is disposed between the slide base Sb as the second movable member that moves together with the movable mold 16 and the mover 31 disposed forward of the slide base Sb, and connects the slide base Sb and the mover 31. The brake 177 that defines the retreat limit position of the slide base Sb is disposed rearward of the slide base Sb and fixed to the frame Fr.

When a predetermined current is supplied to the coil 35 of the linear motor 28 in a state where the mold clamping process is completed, and the movable member 31 starts moving toward the rear from the forward limit position, the spring 171 is sandwiched between the movable member 31 and the slide base Sb, and Elastic contraction. In this state, when the mover 31 is further moved rearward, the slide base Sb is retracted and the mold opening is started.

After the movable member 31 is accelerated to the set speed, the speed is set backward When the square is moved, if the slide base Sb comes into contact with the rear brake 177, the movable mold 16 is stopped as shown in Fig. 4(a), and the mold opening process is ended.

As shown in Fig. 4(b), after the mold opening process is completed, the spring 171 is further contracted by the inertia of the movable member 31 being pressed toward the slide base Sb. At least a portion of the kinetic energy of the movable member 31 is converted into the elastic energy of the spring 171 to decelerate the movable member 31. Therefore, the current flowing to the coil 35 of the linear motor 28 for the deceleration of the movable member 31 can be reduced. During the deceleration of the movable member 31, the energization to the coil 35 of the linear motor 28 can be cut off.

When the deceleration of the movable member 31 is completed, the spring 171 is contracted to the minimum state, and the elastic restoring force of the spring 171 is also maximized. The movable member 31 is biased in the mold closing direction (the right direction in the drawing) by the elastic restoring force of the spring 171.

Next, the mover 31 is accelerated toward the mold closing direction by the elastic restoring force of the spring 171. Thereby, the current flowing to the coil 35 of the linear motor 28 for the acceleration of the movable element 31 can be reduced. When the length of the spring 171 is restored to the natural length, the energization of the coil 35 to the linear motor 28 can be cut off.

When the movable member 31 further advances, the slide base Sb advances away from the brake 177, thereby starting the mold closing process. The molded article is taken out from the stopped movable mold 16 from the end of the mold opening process to the start of the mold closing process.

. In the embodiment, as in the first embodiment, the movable member 31 is When the reverse limit position is folded back, the deceleration and acceleration of the mover 31 are performed by the speed reduction mechanism 170, so that the power consumption of the line motor 28 can be reduced.

In the present embodiment, unlike the first embodiment, the movable member 31 has a dwell time for stopping the slide base Sb or the movable mold 16 during deceleration or acceleration, and at this time, the molded product can be pushed out from the movable mold 16. Therefore, energization of the coil 35 of the linear motor 28 for stopping the movable mold 16 is not required.

Further, in the present embodiment, the slide base Sb is used as the second movable member, but the suction plate 22 or the movable platen 12 may be used. When the movable platen 12 is used, the mover 31 is disposed further forward than the movable platen 12.

Further, in the present embodiment, the coil spring is used as the spring 171, but an air spring may be used, and the structure of the spring is not particularly limited. In addition, rubber may be used as the elastomer instead of the spring 171.

[Third embodiment]

The speed reduction mechanism 70 according to the first embodiment described above absorbs at least a part of the kinetic energy of the mover 31 that is moving in the mold opening direction by the spring 71, and decelerates the mover 31.

On the other hand, the speed reduction mechanism of the present embodiment differs in that the damper absorbs the at least a part of the kinetic energy to decelerate the mover 31. Hereinafter, the description will be centered on differences.

Fig. 5 is an explanatory view of a speed reduction mechanism of the injection molding machine according to the third embodiment. Fig. 5(a) shows the movable member moving in the mold opening direction The state at the time of rapid walking, Fig. 5(b) shows the state at the time of deceleration of the movable member.

The speed reduction mechanism 270 absorbs at least a part of the kinetic energy of the movable member 31 moving in the mold opening direction (the left direction in the drawing) to decelerate the movable member 31. The speed reduction mechanism 270 is constituted by a damper 271 or the like.

Further, when the movable member 31 is decelerated, the speed reducing mechanism 270 can absorb not only the kinetic energy of the movable member 31 but also the member that moves together with the movable member 31 (for example, the sliding base Sb, the suction plate 22, the rod 39, and the movable platen 12). And the kinetic energy of the movable mold 16).

The damper 271 is disposed between the slide base Sb and the orifice 277 as the third movable member that moves together with the mover 31, and is attached only to either one of the slide base Sb and the orifice 277 (5th) In the figure is the orifice 277). The orifice 277 is provided rearward of the slide base Sb and fixed to the frame Fr.

The damper 271 is composed of, for example, a cylinder 272, a piston 273 that can reciprocate in the cylinder 272, and a rod 274 that is coupled to the piston 273. The internal space of the cylinder 272 is partitioned into a front chamber 275 and a rear chamber 276 by a piston 273, and the front chamber 275 and the rear chamber 276 are respectively filled with a liquid such as oil. An orifice 277 is provided in the piston 273. When the piston 273 is pushed backward, the liquid in the rear chamber 276 is moved to the front chamber 275 by the orifice 277, and the force of the piston 273 is sucked rearward by the flow resistance generated at this time. The axial direction of the rod 274 is parallel to the mold opening and closing direction. One end portion of the damper 271 (for example, the cylinder 272) is attached to the orifice 277.

The coil 35 of the linear motor 28 is supplied in a state where the mold clamping process is completed. The predetermined current is applied, and the movable member 31 starts moving toward the rear from the forward limit position, thereby starting the mold opening. After the movable member 31 is accelerated to the set speed, it is moved rearward at the set speed. At this time, the slide base Sb is not in contact with the other end portion (for example, the rod 274) of the damper 271 as shown in Fig. 5(a).

Next, when the slide base Sb comes into contact with the rod 274 and the piston 273 is pushed backward, the liquid in the rear chamber 276 is moved to the front chamber 275 through the orifice 277, and heat is generated by the flow resistance generated at this time. At least a portion of the kinetic energy of the sliding base Sb or the movable member 31 is converted into thermal energy of the liquid, and the sliding base Sb or the movable member 31 is decelerated. Therefore, the current flowing to the coil 35 of the linear motor 28 for the deceleration of the movable member 31 can be reduced. During the deceleration of the movable member 31, the energization to the coil 35 of the linear motor 28 can be cut off.

Then, the movable member 31 is stopped at the retreat limit position, thereby ending the mold opening process. After the end of the mold opening process, the molded article is pushed out from the movable mold 16 by the ejector means. During the ejection of the molded article, the energization of the coil 35 to the linear motor 28 can be cut off.

Next, a predetermined current is supplied to the coil 35 of the linear motor 28, and the movable member 31 is accelerated in the mold closing direction to start mold closing. The position of the piston 273 is returned to the original position after the start of the mold closing to the start of the next mold opening.

In the present embodiment, when the movable member 31 is folded back at the retreat limit position, the deceleration of the movable member 31 is performed by the speed reduction mechanism 270. Therefore, similarly to the first embodiment, the power consumption of the linear motor 28 can be reduced.

The damper 271 is attached only to either one of the orifice 277 and the slide base Sb, so that the damper 271 decelerates the movable member 31 only when the movable member 31 is located near the reverse limit position. Therefore, the constant speed travel of the movable member 31 is stable.

Further, in the present embodiment, the slide base Sb is used as the third movable member, and for example, the suction plate 22 or the movable platen 12 may be used.

In addition, the damper 271 is disposed between the fourth movable member and the movable member 31 that move together with the movable mold 16 in the same manner as the spring 171 of the second embodiment, and connects the fourth movable member and the movable member 31. As the fourth movable member, for example, a slide base Sb, an adsorption plate 22, or a movable platen 12 can be used.

Further, the damper 271 of the present embodiment is an oil damper, but may be an air damper, and the structure of the damper 271 is not particularly limited.

[Fourth embodiment]

The injection molding machine according to the first embodiment includes a speed reduction mechanism that dissipates at least a part of the kinetic energy of the movable member 31 that moves in a predetermined direction by the spring 71 to decelerate the movable member 31.

On the other hand, the injection molding machine of the present embodiment includes an acceleration mechanism that accelerates the movable member in a predetermined direction by the elastic restoring force of the spring. Hereinafter, differences will be mainly described.

Fig. 6 is an explanatory view of an acceleration mechanism of the injection molding machine according to the fourth embodiment. Fig. 6(a) shows the state at the time of mold clamping, and Fig. 6(b) shows the state at the time of mold opening.

The acceleration mechanism 370 is constituted by a spring 371 or the like as an elastic body, and the movable member 31 is accelerated in the mold opening direction by the elastic restoring force of the spring 371. The acceleration mechanism 370 also accelerates the members (for example, the slide base Sb, the suction plate 22, the rod 39, the movable platen 12, and the movable mold 16) that move together with the movable member 31 when the movable member 31 is accelerated.

The spring 371 is, for example, a coil spring, and the direction in which the spring 371 expands and contracts is parallel to the mold opening and closing direction. The spring 371 is disposed between the suction plate 22 and the rear pressure plate 13 that move together with the movable member 31, and is attached only to either one of the suction plate 22 and the rear pressure plate 13 (the rear pressure plate 13 in Fig. 6).

A plurality of springs 371 can be disposed at equal intervals around the rod 39. For example, as shown in Fig. 6, a pair of springs 371 may be disposed above and below the rod 39. The inclination of the suction plate 22 or the rear platen 13 can be reduced by the elastic restoring force of the spring 371.

In the mold closing process, when a predetermined current is supplied to the coil 35 of the linear motor 28, the mover 31 starts moving forward from the backward limit position. After the movable member 31 is accelerated to the set speed, it advances at the set speed. Thereafter, when the mover 31 is decelerated and stopped, the gap between the suction plate 22 and the rear platen 13 becomes a set value. When the movable member 31 is stopped, (1) the suction plate 22 is in contact with the spring 371, the spring 371 is elastically deformable; (2) the suction plate 22 is not in contact with the spring 371, and the spring 371 is in a natural state and is not elastically deformable. In the case of (1), the movable member 31 of the linear motor 28 can be smoothly stopped, and the mold can be closed and closed by the electromagnet 49. On the other hand, in the case of (2), the current supplied to the linear motor 28 can be reduced, and the amount of consumption of electric energy can be reduced.

Next, a predetermined current is supplied to the coil 48 of the electromagnet 49, and the adsorption plate 22 is closed and closed by the adsorption force of the electromagnet 49 close to the rear platen 13.

As shown in Fig. 6(a), in the state at the time of mold clamping, the spring 371 is elastically contracted by being sandwiched between the suction plate 22 and the rear platen 13. The elastic restoring force of the spring 371 is extremely smaller than the suction force by the electromagnet 49.

In the mold opening process, when the energization to the coil 48 of the electromagnet 49 is cut off, as shown in Fig. 6(b), the suction plate 22 or the movable member 31 is accelerated in the mold opening direction by the elastic restoring force of the spring 371. . Therefore, the current flowing to the coil 35 of the linear motor 28 for the acceleration of the movable member 31 can be reduced. When the length of the spring 371 returns to the natural length, the energization of the coil 35 to the linear motor 28 can be cut off.

The spring 371 is attached only to either one of the suction plate 22 and the rear pressure plate 13 (Fig. 6 is the rear pressure plate 13), so that the spring 371 is elastically deformed only when the movable member 31 is located near the forward limit position. Thereby, the constant speed travel of the movable member 31 is stabilized.

Further, in the present embodiment, the spring 371 is elastically deformed by the suction force of the electromagnet 49 that generates the mold clamping force, but the linear motor 28 may be driven to elastically deform the spring 371.

In the above, the first to fourth embodiments of the present invention have been described. However, the present invention is not limited to the above-described embodiments, and various modifications and reversals can be made without departing from the spirit and scope of the invention.

For example, the speed reduction mechanisms 70 to 270 of the above-described embodiment absorb at least a part of the kinetic energy of the movable member 31 that moves in the mold opening direction to move the movable member. The mechanism for decelerating is 31, but it can also be used as a mechanism for absorbing the at least a part of the kinetic energy of the fixing member 31 moving in the mold closing direction to decelerate the movable member 31. Moreover, one injection molding machine can also be provided with two speed reduction mechanisms

10‧‧‧ Injection molding machine

15‧‧‧Fixed mode

16‧‧‧ movable mold

19‧‧‧Molding device

22‧‧‧Adsorption plate

28‧‧‧Line motor

29‧‧‧Fixed parts

31‧‧‧ movable parts

35‧‧‧ coil

60‧‧‧Control Department

70‧‧‧Speed reduction mechanism

71‧‧‧Spring (elastomer)

77‧‧‧Fixed components

271‧‧‧ damper

Sb‧‧Sliding base

Fig. 1 is a view showing a state in which the injection molding machine according to the first embodiment of the present invention is closed.

Fig. 2 is a view showing a state at the time of completion of mold opening by the injection molding machine according to the first embodiment of the present invention.

Fig. 3 is an explanatory view of a speed reduction mechanism of the injection molding machine according to the first embodiment.

Fig. 4 is an explanatory view of a speed reduction mechanism of the injection molding machine according to the second embodiment.

Fig. 5 is an explanatory view of a speed reduction mechanism of the injection molding machine according to the third embodiment.

Fig. 6 is an explanatory view of an acceleration mechanism of the injection molding machine according to the fourth embodiment.

10‧‧‧ Injection molding machine

11‧‧‧Fixed platen

12‧‧‧ movable platen

13‧‧‧ rear platen

13a‧‧‧foot

14‧‧‧ tied

15‧‧‧Fixed mode

16‧‧‧ movable mold

19‧‧‧Molding device

22‧‧‧Adsorption plate

27‧‧‧Installation board

28‧‧‧Line motor

29‧‧‧Fixed parts

31‧‧‧ movable parts

33‧‧‧Magnetic teeth

34‧‧‧ magnetic core

35‧‧‧ coil

37‧‧‧Electromagnetic unit

39‧‧‧ pole

41‧‧‧ rod holes

45‧‧‧ trench

46‧‧‧ magnetic core

47‧‧‧Y yoke

48‧‧‧ coil

49‧‧‧Electromagnet

51‧‧‧Adsorption Department

53‧‧‧ position sensor

55‧‧‧Molding force sensor

60‧‧‧Control Department

70‧‧‧Speed reduction mechanism

71‧‧‧ Spring

77‧‧‧Fixed components

Ba‧‧‧ Position adjustment base

Bb‧‧‧ movable base

Fr‧‧ frame

Gd‧‧‧Guide

N1‧‧‧ nut

Sb‧‧Sliding base

Claims (9)

An injection molding machine comprising: a linear motor comprising a movable member and a fixing member and performing a mold opening and closing operation; and a speed reduction mechanism that absorbs at least a part of kinetic energy of the movable member that moves in a predetermined direction The movable member is decelerated. The injection molding machine according to claim 1, wherein the speed reduction mechanism includes an elastic body that absorbs at least a part of the kinetic energy and is elastically deformed, and the movable member is moved toward the elastic member by the elastic restoring force of the elastic body. The aforementioned predetermined direction is accelerated in the opposite direction. The injection molding machine according to the second aspect of the invention, wherein the elastic body is disposed between the movable member or the first movable member and the fixed member that move together with the movable member, and is attached only to the movable member. Or one of the first movable member and the fixed member. The injection molding machine according to the second aspect of the invention, wherein the elastic body is disposed between the second movable member and the movable member that move together with the movable mold, and connects the second movable member and the movable member . The injection molding machine of claim 1, wherein the speed reduction mechanism includes a damper that absorbs at least a portion of the kinetic energy. The injection molding machine according to claim 5, wherein the damper is disposed between the movable member or the third movable member and the fixed member that move together with the movable member, and is attached only to the movable body. Or one of the third movable member and the aforementioned fixed member. The injection molding machine according to the fifth aspect of the invention, wherein the damper is disposed between the fourth movable member and the movable member that move together with the movable mold, and connects the fourth movable member and the movable member . An injection molding machine comprising: a linear motor comprising a movable member and a fixing member and performing a mold opening and closing operation; and an acceleration mechanism including an elastic body and accelerating the movable member in a predetermined direction by an elastic restoring force of the elastic body. The injection molding machine according to claim 8, wherein the elastic body is elastically deformed by an adsorption force of an electromagnet that generates a mold clamping force, and the elastic body is released by the elastic body. The elastic restoring force accelerates the aforementioned movable member in the mold opening direction.