JPH09201852A - Injection molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accomplink the miniaturization of the entire apparatus by eliminating an exclusive driving source of ejector mechanism by a method wherein the ejector mechanism is operated with the same driving source as that for a mold clamping mechanism. SOLUTION: After supplying molten resin between a stationary mold 27 and a movable mold 28, a motor 39 is reversed to release a pressure contact state to the stationary mold 27 of the movable mold 28, and a mold clamping operation is released. Then, a movable platen 26 is separated from a stationary platen 24 to obtain a mold-released state. Simultaneously therewith, the motor 39 is driven to transfer a ball thread shaft 38 to the movable platen 26 side. An ejector mechanism 65 is operated to push out a molded produce formed in the movable mold 28 from the movable mold 28 with an ejector pin.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an injection molding machine for molding a resin product.

[0002]

2. Description of the Related Art FIG. 8 shows an injection molding machine described in JP-A-63-95925. In FIG. 1, the injection molding machine 1 includes a fixed platen 2 and a movable platen 3 which is arranged so as to face the fixed platen 2 so as to come in contact with and separate from the fixed platen 2.

The fixed platen 2 supports one side of the tie bars 4 and 4, and the movable platen 3 is slidably supported on the tie bars 4 and 4. A ball screw 5 is rotatably supported at a substantially central portion of the fixed platen 2 via a bearing 6. The movable plate 3 side of the ball screw 5 is inserted into the pusher rod 7. A ball screw nut 8 is screwed onto the ball screw 5. The ball screw nut 8 is connected and fixed to the pusher rod 7. Further, the end of the ball screw 5 on the opposite side of the movable plate 3 is inserted into the fixed plate 2 and protrudes to the outside, and the pulley 9 is fixed to the tip part. A belt 10 is wound around the pulley 9 with a drive shaft of a drive motor (not shown).

When the ball screw 5 is rotated by the rotational driving force of the drive motor, the ball screw nut 8 moves in the axial direction of the ball screw 5, and the movable platen 3 comes in contact with and separates from the fixed platen 2.

On the other hand, an ejector pin 11 is axially slidably arranged at a substantially central portion of the movable platen 3.
One end of an ejector ball screw 12 is fixed to the ejector pin 11. The other end of the ejector ball screw 12 has a mold clamping ball screw 5
Is inserted into the hole portion 13 at the tip end of the. The ejector ball screw nut 14 is provided in the pusher rod 7 at an intermediate portion of the ejector ball screw 12.
Is screwed. The rotational driving force of a drive motor (not shown) is transmitted to the ball screw nut 14.

The ball screw nut 1 for the ejector
When 4 is rotated by the driving force of a drive motor (not shown), the ejector ball screw 12 moves in the axial direction, and the ejector pin 11 advances and retreats from the movable platen 3.

In this injection molding machine 1, there is no bending of the movable plate during mold clamping, and the mold clamping force is unevenly distributed to deform the mold and no burrs or the like are generated.

[0008]

However, in the injection molding machine 1, since the motor for driving the ball screw nut 14 for the ejector and the motor for mold clamping are separately installed, the apparatus is miniaturized. Was difficult.

Further, since two motors are required, the manufacturing cost is high.

Therefore, an object of the present invention is to provide an injection molding machine which can be miniaturized and can be manufactured at a reduced cost.

[0011]

In order to achieve the above object, the invention according to claim 1 has a pair of fixed plates arranged at a predetermined interval and one fixed plate between the fixed plates. A movable plate, which is arranged so as to come into contact with and away from the movable plate, a fixed die which is fixed to one fixed plate, a movable die which is fixed to the movable plate so as to face the fixed die, and the movable plate is fixed on one side. A mold opening / closing driving unit that opens and closes between the fixed mold and the movable mold by bringing the movable mold into and out of contact with the board, and a mold clamping mechanism that presses the movable mold toward the fixed mold to bring the movable mold into close contact with the fixed mold. And an ejector mechanism that operates in a mold open state of the movable mold and the fixed mold to push out a molded product from the inside of the movable mold, wherein the ejector mechanism is the same as the mold clamping mechanism. It is operated by a drive source.

In this injection molding machine, since the ejector mechanism operates with the same drive source as the mold clamping mechanism, it is not necessary to separately provide a drive source for the ejector mechanism and a drive source for the mold clamping mechanism. Therefore, the size of the entire device can be reduced.

The invention according to claim 2 is the invention according to claim 1, wherein the mold clamping mechanism is screwed to the ball screw nut rotatably supported on the other stationary platen. A ball screw shaft that moves in the axial direction by the rotation of the ball screw nut, and a mold clamping motor that rotationally drives the ball screw nut to move the ball screw shaft in the axial direction to bring the movable mold into close contact with and abut the fixed mold, The drive source of the ejector mechanism is the mold clamping motor.

In this injection molding machine, the ejector mechanism is actuated by the driving force of the mold clamping motor to push the molded product out of the movable mold. Therefore, since the drive source for the ejector mechanism is not provided, the size of the entire device can be reduced.

A third aspect of the invention is the invention according to the second aspect, wherein the ejector mechanism is slidably arranged in the movable plate and the die clamping motor is driven in the axial direction when the die is opened. It is characterized in that it comprises an eject pin that comes into contact with the ball screw shaft that has moved to, and projects into the movable mold to push out a molded product in the movable mold, and a compression coil spring that pushes back the eject pin into the movable plate.

In this injection molding machine, the ejector pin projects into the movable mold by contacting the ball screw shaft axially moved by the driving force of the mold clamping motor, and the molded product in the movable mold is pushed out. Also, the eject pin is
It is pushed back from the movable die into the movable plate by the urging force of the compression coil spring.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of an injection molding machine according to the present invention will be described with reference to the drawings. 1 is a cross-sectional view showing the configuration of the injection molding machine 22, and FIG. 2 is a left side view of the injection molding machine 22 shown in FIG.

As shown in FIG. 1, the injection molding machine 22 includes a fixed platen 24 fixed on a base 23 at a predetermined interval.
25, a movable plate 26 disposed between these fixed plates 24, 25, and a fixed die 27 fixed to one fixed plate 25.
And a movable die 28 fixed to the movable plate 26 facing the fixed die 27, and the movable plate 26 is moved to one fixed plate 24 side to bring the movable die 28 into contact with the fixed die 27 and move the movable die 28. Mold opening / closing drive means 2 for separating the plate 26 from the fixed plate 24
9 and the movable die 28 toward the fixed die 27 to press the movable die 2
A mold clamping mechanism 30 for closely attaching 8 to the fixed mold 27 and an ejector mechanism 65 for pushing out a molded product from the inside of the movable mold are provided.

The fixed plates 24 and 25 are fixed on the base 23 with bolts 31 at predetermined intervals, and are connected by four tie bars 32 and 32 at four corners (however, only two tie bars are shown in the drawing). It is fixed. These tie bars 32,
The numeral 32 penetrates the movable platen 26, which allows the movable platen 26 to come into contact with and separate from the fixed plate 24 on one side. A mold opening / closing drive means 29 is arranged between the movable platen 26 and the other fixed platen 25.

The mold opening / closing driving means 29 comprises a pair of air cylinders 33 and 34. The air cylinders 33 and 34 have the same structure, and are arranged above and below the fixed plate 25 and the movable plate 26, respectively. The air cylinders 33 and 34 include a cylinder 35 and a rod 3 that is inserted into and removed from the cylinder 35.
6 and the rear end of the cylinder 35 is the other fixed plate 2
5 is fixed to the rod 35 and is inserted into and removed from the cylinder 35.
Is connected to the movable plate 26. When the rod 36 is inserted into the cylinder 35, the movable platen 26 is separated from the fixed platen 24 and positioned on the fixed platen 25 side, and the movable mold 28 and the fixed mold 27 are separated from each other to be in the mold open state. .
Further, when the rod 36 projects from the inside of the cylinder 35, the movable platen 26 is positioned on the other fixed platen 24 side, and the movable mold 28 and the fixed mold 27 come into contact with or come close to each other to be in a mold closed state.

Compressed air is supplied into the cylinders 35 of the air cylinders 33 and 34 by a compressed air supply means (not shown). By changing the pressure of the compressed air, it is possible to change the protruding speed of the rod when protruding from the inside of the cylinder 35 and the insertion speed of the rod when inserting into the cylinder 35.

The mold clamping mechanism 30 has a ball screw nut 37 rotatably supported on the other fixed platen 25, and a ball screw shaft 38 which is screwed into the ball screw nut 37 and moves in the axial direction by the rotation of the ball screw nut 37.
And a motor 39 for driving the ball screw nut 37 to rotate.
And a stopper cylinder 40 projecting from the movable plate 26 toward the other fixed plate 25 side, and a shutter 42 provided in an opening 41 on the other fixed plate 25 side of the stopper cylinder 40.

In the mold clamping mechanism 30, the tip portion 38a of the ball screw shaft 38 is inserted and the inner cylinder 43 arranged between the tip portion 38a of the ball screw shaft 38 and the shutter 42, and the stationary platen 25 on the other side. And a slide outer cylinder 44 that protrudes toward the movable plate 26 side and that supports the outer circumference of the inner cylinder 43 and supports the tip 38a side of the ball screw shaft 38.

The ball screw nut 37 is integrally assembled with the sleeve 45. The sleeve 45 is rotatably supported on the inner wall of the support hole 47 via bearings 46, 46. The support holes 47 are provided in the fixed platen 25 so as to penetrate through the front and back. Further, it is provided on the outer side of the fixed platen 25 between the ball screw nut 37 and the motor 39, and the rotational driving force of the motor 39 is applied to the ball screw nut 37.
There is provided a speed changing means 66 for transmitting to the.

The transmission means 66 includes large-diameter gears 48, 51.
And small gears 49 and 52. As shown in FIGS. 1 and 2, the gear 45 is integrally fixed to the outside of the other fixed platen 25 on the sleeve 45 to which the ball screw nut 37 is assembled. A gear 49 having a smaller diameter than that of the gear 48 meshes with the gear 48. Small diameter gear 49
Is rotatably supported by a rotary shaft 50 protruding outward from the other fixed platen 25.

A gear 51 having a larger diameter than the gear 49 and a smaller diameter than the gear 48 is rotatably supported on the rotary shaft 50. The gear 51 is formed integrally with the gear 49. Therefore, when the gear 49 rotates, the gear 51 also rotates in the same direction as the gear 49. The gear 51 has a small diameter gear 52.
Are engaged. The small-diameter gear 52 is used for the other fixed platen 2.
5 is rotatably supported by a rotary shaft 53 that is provided so as to project. A pulley 54 is rotatably supported on the rotating shaft 53. The pulley 54 is formed integrally with the gear 52. Therefore, when the pulley 54 rotates, the gear 5
2 also rotates in the same direction. In addition, the pulley 54 and the motor 39
The endless belt 55 is wound around the pulley 64 fixed to the drive shaft 39a. The motor 39 is fixed to the lower surface side of the base 23.

Then, the rotational driving force of the motor 39 is transmitted to the rotary shaft 53 via the endless belt 55, and the gears 52,
Transmitted to the sleeve 45 via 51, 49, 48,
The ball screw nut 37 rotates. Ball screw nut 3
When 7 rotates, the ball screw shaft 38 screwed into the ball screw nut 37 moves in the axial direction. In this case, depending on the rotation direction of the motor 39, the ball screw shaft 3
8 moves in the left-right direction in FIG. 1, that is, in the direction toward and away from the fixed platen 24.

A step portion 56 is formed at the end of the ball screw shaft 38 on the movable plate 26 side, and the tip end portion is formed to have a small diameter. A step 57 formed on the inner wall of the inner cylinder 43 is in contact with the step 56.

The inner cylinder 43 is inserted into a slide outer cylinder 44 fixed to the other fixed platen 25. Also, the inner cylinder 4
A slide key 59 is provided between the slide outer cylinder 44 and the inner wall of the slide outer cylinder 44 to restrict rotation of the inner cylinder 43 with respect to the slide outer cylinder 44. Therefore, even if the ball screw shaft 38 rotates, the inner cylinder 43 does not rotate with the rotation. Further, the slide outer cylinder 44 supports the inner cylinder 43, thereby supporting the end portion of the ball screw shaft 38.

On the other hand, a shutter 42 is arranged in an opening 41 on the fixed plate 25 side of a stopper tube 40 provided on the movable plate 26. This shutter 42, as shown in FIG.
A rectangular guide support frame 60 provided around the opening 41 of the stopper tube 40, and the opening 41 in the guide support frame 60.
A pair of slide lids 61, 62 slidably supported between the front side of the opening 41 and a position retracted from the front side of the opening 41 and capable of closing each half of the opening 41, and the slide lids 61, 62. A pair of driven air cylinders 63a, 6
3b. Further, arcuate notches 61a and 62a are formed on the mating surfaces of the slide lids 61 and 62, respectively. The inner diameters of the notches 61a and 62a are slightly larger than the outer diameter of the ball screw shaft 38 and smaller than the outer diameter of the inner cylinder 43. The inner diameter of the stopper cylinder 40 is set to be larger than the outer diameter of the slide cylinder 44 so that the end of the slide cylinder 44 can be accommodated in the stopper cylinder 40.

When the movable platen 26 is located on the other fixed platen 25 side and the mold is open, the shutter 42 is opened and the end of the slide cylinder 44 is inserted into the stopper cylinder 40. Further, when the movable platen 26 is located on the one fixed platen 24 side in the mold closed state, the shutter 42 is in the closed state, and the end surface 43a of the inner cylinder 43 abuts around the notches 61a and 62a of the slide lids 61 and 62. .

In this state, the driving force of the motor 39 causes the ball screw shaft 38 to press the inner cylinder 43 toward the slide lids 61, 61, thereby pressing the stopper cylinder 40.
When the stopper cylinder 40 is pressed, the movable platen 26 is pressed toward one of the fixed plates 24, so that the movable mold 28 comes into close contact with the fixed mold 27 with a predetermined pressing force, and the mold clamping operation is performed.

Behind the slide cylinder 44, the movable platen 2
An eject mechanism 65 is formed at 6 to face the tip portion 38 a of the ball screw shaft 38. The eject mechanism 65 is operated by the driving force of the motor 39 as the drive source of the mold clamping mechanism 30 described above.

As shown in FIGS. 1 and 3, the eject mechanism 65 has a concave portion 67 provided at a substantially central portion of the movable platen 26.
The eject pin 65a that is housed inside and can project toward the movable die 28, and a disc-shaped contact plate 65b that is integrally formed on the stopper cylinder 40 side of the eject pin 65a.
And a compression coil spring 69 arranged between the contact plate 65b and the inner wall 68 in the recess 67 to urge the contact plate 65b toward the stopper cylinder 40. In addition, the fixed plate 2 of the recess 67
The opening on the fifth side is closed by a disk-shaped stopper 71 having an insertion hole 70 formed at the center. The stopper 71 has a contact plate 65b urged by a compression coil spring 69.
Is in contact. In this state, the ejector pin 65a
Are accommodated in the recess 67. Further, the insertion hole 70 is
The ball screw shaft 3 has a diameter larger than that of the contact plate 65b.
8 has a diameter smaller than that of the tip end portion 38a.

When the movable mold 28 is in close contact with the fixed mold 27 and the mold is closed, the compression coil spring 6 is held in the mold clamped state.
The contact plate 65b is biased toward the stopper 71 by the biasing force of 9, and the eject pin 65a is housed in the recess 67. Further, in a mold open state in which the movable mold 28 and the fixed mold 27 are opened, the motor 39 drives the ball screw shaft 38 to move to the movable platen 26 side, and passes between the slide lids 61 and 62 of the shutter 42. The distal end portion 38a thereof is inserted into the insertion hole 70 and abuts against the stopper 71, and further advances to press the stopper 71 to cause the eject pin 65a to project from the inside of the recess 67 against the biasing force of the compression coil spring 69. As a result, the eject pin 65a is moved to the movable mold 28
Protrude into.

Next, the operation of the injection molding machine 22 of this embodiment will be described.

In the fixed position state shown in FIGS. 1 and 4, the movable platen 26 is located on the other fixed platen 25 side, abuts on the shock absorber 67, and the movable mold 28 is separated from the fixed mold 27. Further, in this state, the air cylinders 33, 34
The rod 36 is inserted into the cylinder 35. Further, the slide lids 61 and 62 of the shutter 42 are opened, and the end portion of the slide cylinder 44 is inserted into the stopper cylinder 40. Further, the eject pin 65 a is housed in the recess 67.

From this state, the air cylinders 33 and 34 are operated and the rod 36 is projected from the inside of the cylinder 35. When the rod 36 is projected from the cylinder 35, as shown in FIG.
As shown in FIG. 5, the movable platen 26 moves to the one fixed platen 24 side, and the movable mold 28 abuts the fixed mold 27 to be in the mold closed state. In this state, as shown in FIG.
The end portion of is pulled out from the stopper tube 40. And
The air cylinders 63a and 63b of the shutter 42 are operated, and the opening 41 of the stopper cylinder 40 is closed by the slide lids 61 and 62.

Next, by driving the motor 39 to rotate the ball screw nut 37, the ball screw shaft 3
8 is moved to the movable plate 26 side. Ball screw shaft 3
When 8 moves to the movable platen 26 side, the inner cylinder 43 moves to the movable platen 26.
And the end surface 43a of the inner cylinder 43 is moved to the slide lid 6
It abuts around the notches 61a and 62a of the first and the second 62. After the end surface 43a of the inner cylinder 43 comes into contact with the slide lids 61 and 62, the end surface 43a of the inner cylinder 43 is further slid through the ball screw shaft 38 by driving the motor 39.
When pressed toward 62, the movable platen 26 is pressed to the fixed platen 24 side, the movable mold 28 is pressed against the fixed mold 27 side, and the mold clamping operation is performed.

Then, from this state, the molten resin is press-fitted between the fixed die 27 and the movable die 28 by a resin supply device (not shown). The mold clamping force between the movable mold 28 and the fixed mold 27 is set to be larger than the resin pressure at this time. After the molten resin is supplied between the fixed die 27 and the movable die 28, the motor 39 is rotated in the reverse direction so that the fixed die 27 of the movable die 28 is rotated.
Release the pressure contact condition to and release the mold clamping operation. next,
Operate the air cylinders 63a and 63b to move the slide lid 6
1 and 62 are moved to open the opening 41 of the slipper cylinder 40.

From this state, the air cylinders 33 and 34 are actuated to move the movable platen 26 to the other fixed platen 25 side, and the movable platen 26 is separated from the fixed platen 24 to open the mold. At the same time, as shown in FIG.
The motor 39 is driven to move the ball screw shaft 38 to the movable platen 26 side, and the eject mechanism 65 is operated to push out the molded product formed on the movable mold 28 from the movable mold 28 by the push pin 65a.

In this case, after the movable platen 26 returns to the fixed position, the motor 39 is driven to rotate the ball screw nut 37 and move the ball screw shaft 38 to the movable platen 26 side. When the ball screw shaft 38 moves to the movable platen 26 side, the tip end portion 38a thereof passes through the insertion hole 70 of the stopper 71 and contacts the contact plate 65b. Further, when the ball screw shaft 38 moves to the movable plate 26 side, the eject pin 65a is moved toward the recess 6 against the biasing force of the compression coil spring 69.
7 and the movable die 28. This allows
The eject pin 65 is the molded product that is in close contact with the movable mold 28.
It is pushed by a and is pushed out of the movable mold 28.

When the movable platen 26 moves to the fixed position, the end of the slide outer cylinder 44 is inserted into the stopper cylinder 40 together with the inner cylinder 43 and the tip 38a of the ball screw shaft 38. At the same time, the motor 39 is rotated in the reverse direction to move the ball screw shaft 38 in the reverse direction, that is, toward the other fixed platen 25 side, and the operation of the eject mechanism 65 is stopped. This returns to the initial state shown in FIG. By repeating the above cycle, resin products are continuously molded.

In the injection molding machine 22 of this embodiment, since the ejector mechanism 65 is operated by the motor 39 which is the drive source of the mold clamping mechanism 30, it is not necessary to provide a motor for the ejector mechanism 65 separately from the motor 39. Therefore, the size of the entire device can be reduced.

Further, since the ejector mechanism 65 and the mold clamping mechanism 30 can be operated by one motor 39, the number of motors can be reduced and the manufacturing cost can be reduced. Further, in the injection molding machine 22 of this embodiment, since the driving force of the motor 39 is transmitted to the eject mechanism 65 by using the ball screw nut 37 of the mold clamping mechanism 30 and the ball screw shaft 38, a separate transmission switching means is unnecessary. Therefore, the manufacturing cost can be reduced accordingly.

The driving force of one motor 39 drives a set of the ball screw nut 37 and the ball screw shaft 38, so that the ejector mechanism 65 and the mold clamping mechanism 30 are driven.
Can be operated, so that the motor 39, the ball screw nut 37, and the ball screw shaft 38 can be easily controlled.

Further, in the injection molding machine 22 of this embodiment, when the movable platen 26 is moved to the fixed platen 24 to perform the mold closing operation, since the air cylinders 33 and 34 are used, ball screw nuts and ball screw shafts are used. The manufacturing cost can be reduced as compared with the case where it does not exist.

The air cylinder 3 is used as a mold opening / closing means.
By using 3, 34, the structure is simplified and its operation can be easily controlled. Further, the movable platen 26 can be stably brought into contact with and separated from the fixed platen 24 by using the pair of air cylinders 33 and 34. Further, the air cylinders 33 and 34 are attached to the fixed plate 25 and the movable plate 2.
Since it is arranged between the fixed plate 25 and the movable plate 2,
Since there is no protrusion outside the space surrounded by 6, the injection molding machine 22 can be downsized.

Further, by using the air cylinders 33 and 34, when the movable platen 26 is moved to the fixed platen 24 side, it can be moved quickly, the mold opening / closing time can be shortened, and the molding cycle can be shortened. Since the length can be shortened, it is possible to reduce the manufacturing cost when molding the resin product.

Further, in the injection molding machine 22 of this embodiment, since the mold opening / closing operation is driven by the air cylinders 33 and 34, the pitch of the screw threads of the ball screw nut 37 and the ball screw shaft 38 for performing the mold clamping operation is lengthened. Since it is not necessary to set it, and it can be set short, a high pressure contact force can be obtained.

In this embodiment, the motor 39, the ball screw nut 37 and the ball screw shaft 3 are used only for the mold clamping operation.
8 and the air cylinders 33 and 34 are used for the mold opening / closing operation, the control becomes simple and the maintenance becomes easy.

Further, since the rotational driving force of the motor 39 is transmitted to the ball screw nut 37 via the speed changing means 66, a high torque can be generated by a small motor. Therefore, the size of the injection molding machine can be reduced also by this.

[0053]

As described above, according to the invention of claim 1, since the ejector mechanism operates with the same drive source as the mold clamping mechanism, a drive source for the ejector mechanism and a drive source for the mold clamping mechanism are provided. Need not be provided separately. Therefore, the entire device can be downsized, and the manufacturing cost can be reduced.

According to the second aspect of the invention, the ejector mechanism is actuated by the driving force of the mold clamping motor to push out the molded product from the inside of the movable mold. Therefore, since the drive source for the ejector mechanism is not provided, the size of the entire device can be reduced.

According to the third aspect of the present invention, the eject pin is brought into contact with the ball screw shaft axially moved by the driving force of the mold clamping motor, so that the eject pin projects into the movable mold, so that the molded product in the movable mold is exposed to the outside. Since it is pushed out, the ball screw nut and the ball screw shaft of the mold clamping mechanism can be used when transmitting the driving force of the mold clamping motor, and a means for transmitting the motor driving force to the ejector mechanism is separately provided. There is no need to install it in. Therefore, the manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of an injection molding machine according to the present invention.

FIG. 2 is a front view showing the relationship between the motor of the injection molding machine and the ball screw shaft as seen from the direction of arrow P in FIG.

FIG. 3 is a partially cutaway perspective view showing a relationship between a tip portion of a ball screw shaft, a shutter, and a stopper cylinder.

FIG. 4 is a partially cutaway side view showing a mold open state.

FIG. 5 is a side view showing a mold closed state.

FIG. 6 is a partially cutaway side view showing a state where the mold clamping mechanism is operated.

FIG. 7 is a side view showing a state in which a mold opening operation and an ejector mechanism are activated.

FIG. 8 is a cross-sectional view showing a conventional injection molding machine.

[Explanation of symbols]

 22 injection molding machine 24, 25 fixed plate 26 movable plate 27 fixed type 28 movable type 29 mold opening / closing drive means 30 mold clamping mechanism 37 ball screw nut 38 ball screw shaft 38a tip portion 39 motor 65 eject mechanism 65a eject pin 65b contact plate 69 compression Coil spring

Claims (3)

[Claims] 1. A pair of fixed plates arranged at a predetermined interval, a movable plate arranged between these fixed plates so as to come in contact with and separated from one fixed plate, and one fixed plate. Between the fixed mold and the movable mold, the fixed mold is fixed, the movable mold is fixed to the movable plate so as to face the fixed mold, and the movable plate is brought into contact with and separated from one fixed plate. A mold opening / closing drive means for opening and closing the mold, a mold clamping mechanism for pressing the movable mold toward the fixed mold to bring the movable mold into close contact with the fixed mold, and operating in a mold open state of the movable mold and the fixed mold. An injection molding machine comprising an ejector mechanism for pushing out a molded product from the inside of a movable mold, wherein the ejector mechanism operates with the same drive source as the mold clamping mechanism. 2. The invention according to claim 1, wherein the mold clamping mechanism includes a ball screw nut rotatably supported by the other fixed plate, and a shaft screwed into the ball screw nut by rotation of the ball screw nut. The ejector mechanism includes a ball screw shaft that moves in a direction and a mold clamping motor that rotationally drives a ball screw nut to move the ball screw shaft in the axial direction to bring the movable mold into close contact with and abut the fixed mold. An injection molding machine, characterized in that the source is the mold clamping motor. 3. The ball screw shaft according to claim 2, wherein the ejector mechanism is slidably arranged in the movable plate and moved axially by driving the mold clamping motor in a mold open state. An injection molding machine comprising: an eject pin that abuts and projects into the movable mold to push out a molded product in the movable mold; and a compression coil spring that pushes the eject pin back into the movable plate.