JP2003025056A - Locking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a locking device in which the position of a movable die plate to start the extruding operation of a formed article is adjustable. SOLUTION: The locking device comprises: a movable plate 53 which is connected to an extrusion pin retractable to a moving die and held by the movable die plate 51 movably in the die opening/closing directions A1 and A2; an air cylinder 210 which is provided on the movable die plate 51 to restrict the movable plate 53 to the predetermined position relative to the movable die plate 51 in a releasable manner; an air cylinder 53 which is provided in a link housing 21, restricts the movement of the movable plate 53 in the die opening/closing directions A1 and A2 when the movable die plate 51 moves to the predetermined die opening position PD, and regulates only the movement of the movable plate 53 whose restriction by the air cylinder 210 is released relative to the movable die plate 51 directed from the die opening position PD to further in the die opening direction; and position changing mechanisms 250, 251, 252 and 253 which can change their positions relative to the movable die plate 51 of the air cylinder 210 along the die opening/closing direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold clamping device having an extruding mechanism for extruding a molded product from a mold, which is applied to, for example, a die casting machine or a plastic injection molding machine.

[0002]

2. Description of the Related Art In an injection molding machine for molding a resin such as plastic, a mold clamping device is equipped with an extrusion mechanism for separating a molded product from a mold. The mold clamping device is a device that opens and closes the mold and clamps the mold with a predetermined mold clamping force with the mold closed. In the extrusion mechanism of the mold clamping device described above, for example, an extrusion pin is provided so as to be retractable in the die, and after the product is molded, the extrusion pin is projected in a state where the die is opened and the product is taken out. By the way, conventionally, since the push-out pin of the push-out mechanism is driven by an actuator independent of the actuator for opening and closing the mold, there is a disadvantage that the structure of the mold clamping device becomes complicated and the cost rises.

A technique for performing the opening / closing operation of a mold and the operation of an extrusion mechanism with the same actuator is disclosed in, for example, Japanese Patent Publication No. 4-24.
No. 16 publication. As shown in FIG. 19, the mold clamping device disclosed in Japanese Patent Publication No. 4-2416 clamps a fixed mold 174 and a movable mold 175, and after the injection molding and cooling, the movable mold 175 is moved to a movable die plate. It is equipped with an extruding mechanism that separates it from the fixed mold 174 by 110 and extrudes the molded product by the eject pin 117. Specifically, the crank arm 115 for moving the movable die plate 110 forward and backward, and the crank arm 11
The mold opening / closing motor 107 that drives the die 5 and the eject plate 11 that is disposed inside the moving die plate 110 and is elastically biased in the backward direction by the spring 112.
1 and an eject bar 103 that prevents the eject plate 111 from further retracting by contacting the eject plate 111 with its tip when the eject plate 111 retracts to a predetermined position. In this mold clamping device, when the crank arm 115 is driven and the movable die 175 is opened by the movement of the movable die plate 110, the eject plate 111 comes into contact with the eject bar 103 and the retreat of the eject plate 111 is restricted. Moving die plate 1 with eject plate 111 stopped
When 10 is further retracted, the eject pin 117 projects toward the movable die 175 while the spring 112 is compressed. As a result, the molded product is extruded from the moving mold 175. When the movable die plate 110 is moved forward by driving the crank arm 115, the eject plate 11
1 is separated from the eject bar 103, and the eject pin 117 is moved by the urging force of the spring 112.
It immerses in 75 and returns to a fixed position.

[0004]

By the way, as in the above structure, a die-casting machine is used in place of the plastic injection molding machine as the mold clamping device having the extrusion mechanism for operating the eject pin 117 in cooperation with the opening / closing operation of the mold. It is possible to apply to. However, a die casting machine uses a molten metal such as an aluminum alloy as a molding material. Therefore, a part of the molten metal injected into the mold is scattered to the moving die plate 110, and the moving die plate 11
There is a possibility that it will adhere to the spring 112 provided inside the zero. If the molten metal adheres to the spring 112 and solidifies, the spring 112 may not expand or contract normally.
In the above-mentioned extrusion mechanism, if the eject pin 117 moved with respect to the movable die plate 110 does not normally expand and contract the spring 112, for example, the movable die 175 and the fixed die 174 are closed after the product pushing operation is completed. In this state, the eject pin 117 may not return to the fixed position and may protrude into the movable die 175. If molding is performed with the eject pin 117 protruding from the moving mold 175, there is a risk of molding failure. Especially, when the core is inserted into the mold for molding, the eject pin 11
If 7 protrudes, the mold may be damaged.

The present invention has been made in view of the above problems, and an object thereof is to provide a mold clamping device capable of reliably operating an extrusion pin in cooperation with the opening / closing operation of a mold. To do.

[0006]

A mold clamping device of the present invention comprises a fixed die plate for holding a fixed die, a movable die plate for holding a movable die opposed to the fixed die, and the movable die. A mold clamping device, comprising: a link housing provided with a drive mechanism that moves a plate in a mold opening / closing direction and supplies a mold clamping force; A movable member that is connected to a push-out pin that can be retracted and is held by the movable die plate so as to be movable in the mold opening and closing direction; A first restraint for releasably restraining the movable member in a mold opening / closing direction when the movable die plate is provided in the link housing and moves to a predetermined mold opening position. And second restraint means for restraining only the movement of the movable member that has been released from the restraint by the first restraint means with respect to the moving die plate that is further restrained from the die open position in the die opening direction. And a restraint position adjusting means capable of changing the position of the movable die plate when restraining of the movable member is started by the second restraining means.

Preferably, the restraint position adjusting means has a position adjusting mechanism capable of changing the position of the first restraining means with respect to the movable die plate along the mold opening / closing direction.

In the mold clamping device of the present invention, since the movable member connected to the extrusion pin is constrained by the first constraining means until the movable die plate moves to a predetermined mold opening position, the movable member moves. It is securely in place with respect to the die plate. When the movable die plate of the movable member moves to a predetermined mold opening position, the movement of the movable member in the mold opening / closing direction is restricted by the second restricting means. Immediately before the movable member and the movable die plate relatively move, the restraint by the first restraint means is released, and the relative movement between the movable member and the movable die plate causes the extrusion pin to project with respect to the movable die. The molded product is extruded. When the moving die plate returns to the predetermined mold opening position again after the above-described extrusion operation of the molded product is completed, the movable member surely returns to the fixed position with respect to the moving die plate. The movable member in this state is restrained again by the first restraining means. Therefore, the mold clamping operation is not performed in a state where the movable member is dislocated from the fixed position and the push pin projects from the movable mold. Further, in the mold clamping device of the present invention, the pushing position of the molded product can be arbitrarily changed by changing the position of the moving die plate when the restraining of the movable member is started by the restraining position adjusting means. .

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. First Embodiment FIG. 1 is a configuration diagram showing an example of a mold clamping device to which the present invention is applied, and the mold clamping device 1 shown in FIG. 1 is applied to mold clamping of a die casting machine, for example. In FIG. 1, the mold clamping device 1 includes a base 100, a fixed die plate 91 fixed on the base 100, a fixed mold 92 attached to the fixed die plate 91, and a base facing the fixed die plate 91. A movable die plate 51 movably provided on 100, a movable die 52 attached to the movable die plate 51 so as to face the fixed die 92, and a fixed die plate 91 with the movable die plate 51 interposed therebetween. A link housing 21 connected by a tie bar 95,
A toggle mold clamping mechanism 109 that connects the link housing 21 and the movable die plate 51 is provided.

The fixed die plate 91 is fixed to the base 100. The link housing 21 is normally fixed to the tie bar 95, but moves with respect to the tie bar 95 when adjusting the die height accompanying the die replacement. The movable die plate 51 is provided so as to be movable on the base.
The link housing 21 and the fixed die plate 91 are connected by a tie bar 95 penetrating the movable die plate 51, and normally four tie bars 95 are provided.

The toggle mold clamping mechanism 109 for connecting the link housing 21 and the movable die plate 51 is provided with two sets of upper and lower link systems 110 in FIG. 1, and only one structure thereof is shown in detail. Each link system is composed of a plurality of links. Each link system includes an angle-shaped first link 110-1 and a linear link 110-2.
One end of the first link 110-1 is pivotally attached to the link housing 21 and the other end is pivotally attached to the crosshead 105. Second link 1
One end of the first link 10-2 is located between the link housing 21 and the pivot point of the crosshead 105.
10-1 and the other end of the movable die plate 51. The crosshead 105 pivotally attached to the first link of the toggle mechanism 109 moves along the screw shaft 106 in the direction of arrow A1 or A2, whereby the toggle mechanism 109 operates and the link housing 21 and the moving die plate 51 are separated from each other. Move closer or further away. The screw shaft 106 is
As will be described later, the cross head 105 driven by a servo motor provided in the link housing 21 and screwed with the screw shaft 106 moves in the direction of arrow A1 or A2.

As shown in FIG. 1, as the crosshead 105 moves in the direction of arrow A2, the toggle mechanism 109 operates and the moving die plate 51 moves in a direction away from the link housing 21 (the mold closing direction). , Fixed mold 92
Then, the movable die 52 is closed, and when the crosshead 105 is further moved in the direction of arrow A2, tension acts on the tie bar 95 to tighten the fixed die 92 and the movable die 52. With the moving mold 52 and the fixed mold 92 clamped, a cavity formed by the moving mold 52 and the fixed mold 92 is injected and filled with a molten metal such as an aluminum alloy by an injection device (not shown). Mold die cast products.

On the other hand, in order to mold the die cast product, open the movable die 52 and take out the die cast product,
As shown in FIG. 7, as the crosshead 105 moves in the arrow A1 direction, the moving die plate 51 moves the toggle mechanism 10
The movable die 52 opens with respect to the fixed die 92 by moving in a direction approaching the link housing 21 (die opening direction) via the link 110 of 9. At this time, the die-cast product in the movable die 52 is extruded by the extruding mechanism described later.

FIG. 3 is a plan view showing the structure around the link housing 21 and the movable die plate of the mold clamping device according to the embodiment of the present invention. FIG. 4 is a rear view of the link housing 21 as seen from the direction of arrow C shown in FIG. FIG. 5 is a rear view showing the movable die plate 51 in a partial cross section as seen from the direction of arrow D shown in FIG. FIG. 6 is a front view showing a partial cross section of the link housing 21 as seen from the direction of arrow E shown in FIG.

In FIG. 3, a mold clamping servomotor 30 and a die height adjusting motor 41 are provided on both sides of the link housing 21, respectively.
As shown in, the pulley 30a is fixed to the output shaft of the mold clamping servomotor 30, and the gear 42 is fixed to the output shaft of the die height adjusting motor 41. As shown in FIG. 4, a screw shaft 106 is rotatably supported at the center of the link housing 21 along the mold opening / closing directions A1 and A2, and a pulley 106a is provided at the rear end of the screw shaft 106. Is fixed. This pulley 106a,
The toothed belt 31 is wound around the pulley 30a fixed to the output shaft of the mold clamping servomotor 30 described above.
The rotational force of the mold clamping servomotor 30 is transmitted to the screw shaft 106.

A ring gear 43, which is arranged concentrically with the screw shaft 106, is rotatably supported on the back side of the link housing 21, and the ring gear 43 is fixed to the output shaft of the die height adjusting motor 41. It meshes with the gear 42. At four corners of the link housing 21, gear wheels are formed on the outer circumference, and tie bar nuts 46 that are screwed into the threaded portions on the outer circumference of the tie bar 95 are rotatably held, and these tie bar nuts 46 mesh with the ring gear 43, respectively. . The rotational force of the die height adjusting motor 41 is
The gear 46 and the ring gear 43 meet and are transmitted to the tie bar nut 46, whereby the link housing 21 moves along the axial direction of the tie bar 95. The movable die plate 51 is in a state where the movable die 52 and the fixed die 92 are in contact with each other and a mold clamping force is not generated between them.
The distance between the fixed die plate 91 and the fixed die plate 91 is called a die height, and the die height can be adjusted by adjusting the position of the link housing 21 according to the heights of the movable die 52 and the fixed die 92.

In FIG. 3, a crosshead 105 is screwed onto the screw shaft 106.
Is driven in the mold opening / closing direction A1 or A by driving the screw shaft 106.
Move to 2. On both sides 105a of the crosshead 105, the mold opening / closing direction A1 provided in the link housing 21 is provided.
Alternatively, two guide bars 23 provided along A2 are fitted and inserted. The rear end of this guide bar 23 is
It is fixed to the link housing 21, and the tip end portion is supported by a support portion 22 formed in the link housing 21 and extending along the mold opening / closing direction A1 or A2.

As shown in FIGS. 3 and 6, the cross head 105 has a link 110-1 (see FIGS. 1 and 2) of a toggle mechanism 109 for connecting the movable die plate 51 and the link housing 21, as shown in FIGS. (See 2)
A connecting portion 105b connected to is formed. An expandable cover 26 that surrounds the screw shaft 106 is provided between the tip of the screw shaft 106 and the crosshead 105 to prevent foreign matter such as molten metal from adhering to the screw shaft 106.

As shown in FIGS. 3 and 6, a clamp member 24 is provided on the tip side of the support portion 22 of the link housing 21, and the clamp member 24 has a mold opening / closing direction A1 or Insert hole 2 along A2
4a is formed. An air cylinder 25 is provided above the clamping members 24. The air cylinder 25 is an embodiment of the actuator of the present invention. In these air cylinders 25, the built-in piston rod can be retracted into the insertion hole 24a of the clamp member 24. The air cylinder 25 is arranged so that the piston rod is orthogonal to the central axis of the insertion hole 24a.

The movable die plate 51 is provided with a movable plate 53 on the side opposite to the side holding the movable die 52. The movable plate 53 is an embodiment of the movable member of the present invention.
As shown in FIGS. 3 and 5, the movable plate 53 is moved in the mold opening / closing directions A1 and A by the guide rods 55 provided upright on the side surfaces of the main body 51a of the moving die plate 51, respectively.
It is held so as to be movable in two directions. A fitting portion 53 a that fits into the guide rod 55 is formed on one surface of the movable plate 53, and the fitting portion 53 a is fitted into the guide rod 55.
Is fitted to.

Stoppers 56 made of double nuts are fixed to the distal end portions of the guide rods 55, respectively.
The movable plate 53 is prevented from coming off by the stopper 56. A coil spring 60 is inserted in the guide rod 55 between the movable plate 53 and the facing surface of the movable die plate 51. The coil spring 60 is an embodiment of the biasing means of the present invention.

The coil spring 60 elastically biases the movable plate 53 toward the die opening direction A1, and the movable plate 53 abuts the stopper 56 which is the movement limit position in the die opening direction A1 by this biasing force. Held in position. That is, the position where the movable plate 53 contacts the stopper 56 is the fixed position.

On the surface of the movable plate 53 facing the link housing 21, a hook member 58 to be inserted into the insertion hole 24a of the clamp member 24 provided at the tip of the support portion 22 of the link housing 21 is provided. It is provided corresponding to. The hook member 58 has a locking recess 59 formed at the front end for locking the front end of the piston rod of the air cylinder 25 described above. Further, the brim-shaped stopper portion 58a formed on the shaft portion of the hook member 58 has a hook member 58 for the clamp member 24 when the tip end portion of the hook member 58 is inserted into the insertion hole 24a of the clamp member 24. For defining the position of. here,
The air cylinder 25, the clamp member 24, and the hook member 58 form an embodiment of the restraint means of the present invention.

The movable die 52 has a plurality of push-out pins 6.
3 is provided so as to be retractable from the inner surface of the movable die 52. These push-out pins 63 are connected to a push-out plate 68 arranged behind the movable mold 52. Extruded plate 68
Is held by a guide pin 65 fixed to the back of the movable mold 52 so as to be movable in the mold opening / closing directions A1 and A2. A plurality of coil springs 64 are provided between the pushing plate 68 and the moving die 52, and the pushing plate 6
A force is applied to separate the moving mold 52 from the moving mold 8.

The pushing plate 68 is moved by the plurality of connecting rods 54 penetrating the inside of the moving die plate 51.
It is connected with 3. Movable plate 5 by connecting rod 54
3 and the push-out plate 68 are connected, the movable plate 53
And the extruding pin 63 are connected to each other, and the extruding pin 63 projects in and out of the die inner surface of the moving die 52 in association with the relative movement of the movable plate 53 with respect to the moving die plate 51.

Next, the operation of the mold clamping device 1 having the above structure will be described. In the mold clamping device 1 in the state shown in FIG. 3, the fixed mold 92 and the movable mold 52 are in the mold clamping state. From this state, the mold clamping servomotor 30 is driven to rotate the screw shaft 106 in a predetermined direction to move the crosshead 105 in the mold opening direction A1.

When the cross head 105 is moved in the mold opening direction A1, the moving die plate 51 moves toward the link housing 21 and the fixed mold 92 moves by the above-mentioned toggle mechanism 109, as shown in FIG. Open to mold 52. At this time, the die-cast product W molded in the cavity formed by the fixed mold 92 and the movable mold 52.
Moves together with the moving mold 52 as shown in FIG.

When the movable die plate 51 moves to the mold opening limit position PA which is a predetermined mold opening position, the hook member 58 provided on the movable plate 53 is inserted into the insertion hole of the clamp member 24 provided on the link housing 21. 24a is inserted. Therefore, the movable plate 53 is connected to the link housing 21 via the clamp member 24 and the hook member 58.

Here, FIG. 9 is a side view showing a state in which the movable plate 53 is clamped to the link housing 21, and in the lower half of FIG. 9, the movable die plate 51 has moved to the mold open position PA. It shows the state. As shown in FIG. 9, when the hook member 58 provided on the movable plate 53 is inserted into the insertion hole 24a of the clamping member 24, the air cylinder 25 is driven to drive the piston rod 2 of the air cylinder 25.
5a is projected and locked in the locking recess 59 of the hook member 58. As a result, the movable plate 53 becomes the link housing 2
1, the movement of the movable plate 53 in the mold opening / closing directions A1 and A2 is restricted.

Next, from the above state, the crosshead 1
05 is further moved in the mold opening direction A1, and the moving die plate 51 is further moved from the mold opening limit position PA to the extrusion position PB in the mold opening direction A1 as shown in FIG. The upper half of FIG. 9 shows a state in which the movable die plate 51 has been moved from the mold opening limit position PA to the extrusion position PB in the mold opening direction A1. Since the movable plate 53 is constrained by the link housing 21, the movable die plate 51 moves in the mold opening direction A.
Even if the movable plate 53 is further moved to 1, the movable plate 53 is prevented from moving.
Therefore, relative movement occurs between the movable die plate 51 and the movable plate 53 in the mold opening / closing directions A1 and A2. As can be seen from FIG. 9, the movable die plate 51 and the movable plate 5
When a relative movement occurs between the coil spring 60 and the coil 3, the coil spring 60 is compressed.

Further, as shown in FIG. 8, when only the movement of the movable plate 53 in the die opening direction A1 is blocked, the pushing plate 68 provided behind the movable die 52 resists the biasing force of the coil spring 64. Then, the moving mold 52 is approached. When the pushing plate 68 approaches the moving mold 52, the pushing pin 63 projects from the moving mold 52 and pushes out the die-cast product W in the moving mold 52. This completes the removal of the die cast product W from the mold.

Next, from the above state, the direction of rotation of the mold clamping servomotor 30 is reversed to move the movable die plate 51.
Is moved from the extrusion position PB to the mold opening position PA. At this time, the movable plate 53 remains restrained with respect to the link housing 21. Moving die plate 5
When 1 moves to the mold open position PA, the state shown in FIG. 7 is reached, and the movable plate 53 comes into contact with the stopper 56 at the tip of the guide rod 55 and returns to the fixed position with respect to the moving die plate 51. Further, the push-out pin 63 surely sinks from the mold inner surface of the movable mold 52, and the compressed coil spring 60 is restored.

In this state, the movable plate 53 is restrained with respect to the link housing 21 and is in a fixed position with respect to the movable die plate 51, so that the movable die plate 51 cannot move in the mold closing direction A2. It has been blocked. That is, in the mold open state, the moving die plate 51 keeps the mold closing direction A until the clamp by the air cylinder 25 is released.
It is possible to prevent the moving die plate 51 from moving in the mold closing direction A2 even if the mold clamping servomotor 30 is erroneously operated without moving to the mold closing direction A2.

When the mold is clamped again from this state,
After detecting the mold clamping signal to the control device of the mold clamping device 1, the air cylinder 25 is driven to drive the piston rod 25a.
Is retracted into the hook member 58 to release the clamp operation of the movable plate 53.

As described above, according to the mold clamping device 1 of the present embodiment, the actuator for pushing out is not required, and the mold for the die-cast product is moved from the movable mold 52 in cooperation with the mold opening operation of the movable die plate 51. Extrusion can be performed.
Further, in the mold clamping device 1 of the present embodiment, the movable die plate 51 is moved to the mold open position PA, and the extrusion position P
After the moving die plate 51 is moved to B and the die casting product is extruded from the moving die 52, the moving die plate 51 is kept restrained until the moving die plate 51 is returned to the die open position PA again. 51 is the mold open position PA
The extrusion pin 63 can be reliably retracted from the inner surface of the mold of the moving mold 52 when moved to the position. That is, in the present embodiment, the pushing pin 63 that has been pushed out is not moved into the moving die 52 by the urging force of the coil spring 60, but is moved by moving the moving die plate 51. Even when the coil spring 60 does not expand and contract properly due to the sticking of the push pin 63, the push pin 63 can be reliably returned to the fixed position.

Further, in the present embodiment, the movable plate 53 is restrained by the link housing 21 so that the mold opening limit position PA.
It is possible to obtain a function of a safety mechanism for surely preventing the movable die plate 51 in FIG. 6 from accidentally moving in the mold closing direction A2, and the movable mold 52 and the fixed mold 9 in the mold open state.
It is possible to safely and reliably clean the second mold 2 and prevent damage to the movable mold 52 and the fixed mold 92. Further, since the safety mechanism and the pushing mechanism can be used in common, the device configuration can be further simplified.

The present invention is not limited to the above embodiment. In the above-described embodiment, the case where the air cylinder 25 is used as an actuator for restraining the movable plate 53 has been described. However, for example, a hydraulic cylinder, a motor, a strong electromagnet, or the like, which has a high responsiveness to the movable plate 53 to the link housing. Any means that can be restrained may be used. Further, in the above-described embodiment, the case of the coil spring is described as one embodiment of the biasing means of the present invention, but in addition to this,
For example, the movable plate 53 may be biased toward a fixed position by utilizing the attraction force or repulsive force of a magnet, or compressed air may be blown to the movable plate 53 toward a fixed position. It is also possible to set it as a vibrating structure.
Further, in the above-described embodiment, the air cylinder 25, the clamp member 24, and the hook member 58 are provided at a plurality of positions from the viewpoint of clamping force, balance, etc., but they may be provided singly. Further, the air cylinder 25 and the clamp member 2
4 is provided in the link housing 21 and the hook member 58 is provided in the movable plate 53, but the air cylinder 25 and the clamping member 24 may be provided in the movable plate 53 and the hook member 58 may be provided in the link housing 21. is there.

Second Embodiment FIG. 10 is a plan view showing a structure around a link housing and a movable die plate of a mold clamping device according to a second embodiment of the present invention. The mold clamping device according to the present embodiment differs from the mold clamping device according to the first embodiment described above only in a part of the configuration of the movable die plate 51, and the other configurations are the same, and the same. The components will be described with the same reference numerals. In FIG. 10, the link housing 2
The above-mentioned clamp member 24 and air cylinder 25 are provided at the tip of the support portion 22 of No. 1, and these constitute the second restraint means of the present invention.

A movable plate 53 is provided on the movable die plate 51 along the guide rod 55 so as to be movable in the mold opening / closing directions A1 and A2. In FIG. 10, the movable plate 53 contacts the stopper 56. In position. A plurality of hook members 201 are provided on the surface of the movable plate 53 on the link housing 21 side. This hook member 201
At the tip of the, the piston rod 25 of the air cylinder 25
A locking recess 202 for locking a is formed. The hook member 201 is the hook member 58 in the first embodiment.
Has a slightly different shape, but performs the same function as the hook member 58.

Further, locking members 203 are provided on both sides of the movable plate 53. A locking recess 203a is formed on the outer surface of the locking member 203.

Air cylinders 210 are provided on both sides of the movable die plate 51 at positions facing the locking members 203 of the movable plate 53 in a fixed position. The tip portion 211a of the piston rod 211 built into the air cylinder 210 can be fitted into the locking recess 203a of the locking member 203 by the piston rod 211 extending from the air cylinder 210. When the tip end portion 211a of the piston rod 211 engages with the locking recess 203a of the locking member 203, the movable plate 53 is restrained from moving from the fixed position of the movable die plate 51. That is, it becomes impossible to move in the mold opening / closing directions A1 and A2 with respect to the moving die plate 51.

Next, the operation of the mold clamping device having the above structure will be described. In the mold clamping device in the state shown in FIG. 10, the fixed mold 92 and the movable mold 52 are in the mold clamped state, and the movable die plate 51 is in a fixed position. In this state, the air cylinder 210 is driven, the piston rod 211 is projected, and the movable plate 53 is restrained with respect to the movable die plate 51.

From this state, when the movable die plate 51 is moved in the mold opening direction A1 as in the case of the first embodiment, the movable die plate 51 is moved to the mold open position PA as shown in FIG. When moved, the tip end portion of the hook member 201 is inserted into the insertion hole 24a of the clamp member 24.

In this state, the air cylinder 25 is operated and the piston rod of the air cylinder 25 is moved to the hook member 2.
01 is locked in the locking recess 202 and clamped. As a result, the movable plate 53 is restrained with respect to the link housing 21.

When the movable plate 53 is restrained to the link housing 21 by the air cylinder 25, then, as shown in FIG.
1 is immersed, and the constraint of the movable plate 53 on the movable die plate 51 is released. This allows the movable plate 53 to move relative to the movable die plate 51.

Then, as shown in FIG. 13, the movable die plate 51 is further moved from the mold opening limit position PA in the mold opening direction A1 to the extrusion position PB. As a result, the movable plate 53 moves relative to the movable die plate 51 in the mold closing direction A2, and the die cast product is extruded by the extrusion pin. In this state, the movable plate 53 is out of the fixed position of the movable die plate 51.

When the extrusion of the die cast product is completed,
As shown in FIG. 14, the movable die plate 51 is moved again to the mold open position PA. As a result, the movable plate 53 returns to the fixed position of the movable die plate 51. Further, the push-out pin 63 surely sinks from the mold inner surface of the movable mold 52. Then, the piston rod 211 of the air cylinder 210 is extended, and the restraint of the movable plate 53 on the moving die plate 51 is restarted.

In this state, the movable plate 53 is restrained with respect to the link housing 21 and is in a fixed position with respect to the movable die plate 51, so that the movable die plate 51 is not movable in the mold closing direction A2. It has been blocked. That is, in the mold open state in which mold clamping is not performed, the moving die plate 51 does not move in the mold closing direction A2 until the clamp by the air cylinder 25 is released, and the mold clamping servomotor 30 operates erroneously. Can also prevent the moving die plate 51 from moving in the mold closing direction A2.

When the mold is clamped again from this state,
After detecting the mold clamping signal to the control device of the mold clamping device 1, the air cylinder 25 is driven to drive the piston rod 25a.
Is retracted into the hook member 58 to release the clamp. At this time, the clamp of the movable plate 53 by the air cylinder 210 is not released. Therefore, the movable plate 53 is reliably positioned at the fixed position of the movable die plate 51 until the next pushing operation.

As described above, according to the present embodiment, the push pin 63 is moved by constantly clamping the movable plate 53 by the air cylinder 210 except when the movable plate 53 and the movable die plate 51 are relatively moved. The mold 52 can be surely immersed from the inner surface of the mold, and the position of the extrusion pin 63 can be accurately controlled. Further, according to the present embodiment, as in the first embodiment described above, the safety mechanism and the pushing mechanism can be used in common, so that the device configuration can be simplified.

In the above-described embodiment, the case where the air cylinders 25 and 210 are used as the actuator has been described, but an actuator having a relatively high response such as a hydraulic cylinder, a motor, a strong electromagnet or the like may be used. Further, in the above-described embodiment, the air cylinder 25,
Although 210 is provided at a plurality of locations, it may be provided at a single location.

Further, although the air cylinders 25 and 210 are provided separately in the above-described embodiment, for example, FIG.
As shown in, it is possible to integrate these. In FIG. 15A, the movable plate 53 is provided with an air cylinder 301 from which both ends of the piston rod 302 can project. In addition, the moving die plate 51
The piston rod 30 of the air cylinder 301
A locking recess 304 capable of locking 2 is formed. On the other hand, the link housing 21 is provided with a locking member 305 having a locking recess 305a capable of locking the piston rod 302 of the air cylinder 301.

When the state shown in FIG. 15A is the mold clamping state, the movable plate 53 can be clamped at the fixed position of the movable die plate 51 by the air cylinder 301. As shown in FIG. 15B, when the movable die plate 51 is moved to the mold open position, the piston rod 302 of the air cylinder 301 is projected in the opposite direction to lock the locking member 305.
To be locked. As a result, the movable plate 53 is restrained by the link housing 21. At the same time, the restrained state of the movable plate 53 with respect to the movable die plate 51 is released. In this way, the movement of the movable plate 53 is restrained from the fixed position of the movable die plate 51, and the movable plate 53 moved to the mold open position.
By selectively restraining the movement of the mold in the mold opening / closing direction, the number of air cylinders to be used can be reduced and the cost can be reduced.

Third Embodiment FIG. 16 is a plan view showing the structure around a link housing and a movable die plate of a mold clamping device according to a third embodiment of the present invention. In the above-described first and second embodiments, unless the movable die plate 51 is moved to the mold open position PA, the extrusion operation of the molded product cannot be performed. For example, when the molded product is thin, it can be pushed out without moving the movable die plate 51 to the mold open position PA. Further, if the movable die plate 51 is always moved to the mold open position PA, there is a disadvantage that the cycle time becomes long. In the present embodiment, the pushing operation can be performed without constantly moving the movable die plate 51 to the mold open position PA, that is, the position of the movable die plate 51 when the constraint of the movable plate is started can be changed. The configuration will be described.

The mold clamping device according to the present embodiment and the above-mentioned second
The mold clamping device according to the embodiment is basically the same in structure, and is different only in a part of the structure of the movable die plate 51 and is the same in other structures.
Therefore, the same components and components having the same basic function will be described using the same reference numerals. FIG.
In the above, the air cylinder 25 described above is provided at the tip of the support portion 22 of the link housing 21. A plurality of hook members 201 are provided on the movable plate 53 so as to extend in the mold opening / closing directions A1 and A2. A locking recess 202 for locking the piston rod 25a of the air cylinder 25 is formed at the tip of the hook member 201. The hook member 201 has a different shape from the hook member 201 in the second embodiment, but performs the same function.

The plurality of air cylinders 210 are not fixed to the movable die plate 51, but the slider 25.
It is fixed at 0 respectively. A ball screw 251 is screwed into one end of the slider 250. The ball screw 251 has a servo motor 252 having one end in a released state and the other end fixed to the moving die plate 51.
Is connected to the rotary shaft 252a. Ball screw 251
Is arranged along the mold opening and closing directions A1 and A2, and
It is rotatably supported. A guide rod 253 is inserted on the other end side of the slider 250. The guide rod 253 has one end in a released state and the other end
It is fixed to the movable die plate 51 by a fixing member 254. The guide rod 253 is arranged along the mold opening / closing directions A1 and A2. The slider 250 is supported by a guide rod 253 so as to be movable along the mold opening / closing directions A1 and A2.

The slider 250 is composed of the ball screw 25 described above.
1 and the guide rod 253 so as to be movable in the mold opening / closing directions A1 and A2. Servo motor 252
When is rotated, the rotational force of the servo motor 252 is converted into a direct power, and the slider 250 moves in the mold opening / closing directions A1 and A2. By controlling the rotational position of the servo motor 252, the slider 250 is positioned in the mold opening / closing directions A1 and A2.

In FIG. 16, the movable plate 53 is movable along the guide rod 55.
A locking recess 53a into which the tip portion 211a of the piston rod 211 of the air cylinder 210 is fitted is formed in the. The locking recess 53a has the same function as the locking recess 203a of the locking member 203 described in the second embodiment. When the piston rod 211 extends to fit into the locking recess 53a of the movable plate 53, the movement of the movable plate 53 from the fixed position of the movable die plate 51 is restricted. That is, it becomes impossible to move in the mold opening / closing directions A1 and A2 with respect to the moving die plate 51.

The restraining position of the movable plate 53 is the air cylinder 2
It depends on the positions of the mold opening and closing directions A1 and A2. That is, by positioning the slider 250 at a desired position in the mold opening / closing directions A1 and A2, the movable plate 5 is moved.
The restraint position of 3 can be adjusted to a desired position. The slider 250, the ball screw 251, the servo motor 252, and the guide rod 253 constitute the position adjusting mechanism of the present invention.

Next, an example of the operation of the mold clamping device having the above structure will be described with reference to FIGS. 17 and 18. When it is desired to change the position of the movable die plate 51 for starting the extrusion operation of the molded product from the above-mentioned mold opening position PA,
As shown in FIG.
It is moved by a predetermined distance La from 1 toward the mold opening direction A1. The movable plate 53 is restrained by the air cylinder 210. The distance La is the amount of change in the position of the moving die plate 51 that starts the extrusion operation of the molded product.

When the slider 250 is moved by the distance La, the position of the movable plate 53 with respect to the moving die plate 51 is changed. In FIG. 17, the moving die plate 51 in a state where the moving die 52 and the fixed die 92 are closed.
When the position of is the mold closing position PC, when the molding of the molded product is completed, the moving die plate 51 is moved from the mold closing position PC in the mold opening direction A1.

Next, as shown in FIG. 18, the movable die plate 51 is positioned at the extrusion operation start position PD before the mold opening position PA. This extrusion operation start position PD
Is a distance La from the mold open position PA, as shown in FIG.
Only at the position close to the mold closing direction A2. After the movable die plate 51 is positioned at the push-out operation start position PD, the piston rod 25a of the air cylinder 25 is extended, and the piston rod 25a is locked by the locking recess 20 of the hook member 201.
Fit to 2. The piston rod 25a is the hook member 20.
After fitting into the locking recess 202 of No. 1, the air cylinder 21
The piston rod 211 of 0 contracts and the restraint of the movable plate 53 by the air cylinder 210 is released. The subsequent operation is exactly the same as that of the second embodiment described above, and the moving die plate 51 is further moved from the extrusion operation start position PD in the mold opening direction A1 to extrude the molded product.

As described above, according to this embodiment, since the extrusion operation start position for starting the extrusion operation of the molded product can be changed, the movable die plate 51 is moved to the mold closing position for each extrusion operation of the molded product. There is no need to move from the PC to the mold open position PA. As a result, the cycle time of the die casting machine can be shortened. Further, since the position of the air cylinder 210 as the first restraint means can be adjusted by an actuator such as a servomotor, for example, the specifications of the mold are input to the control device, and the specifications of the mold are input according to the specifications. It is possible to automatically adjust the starting position of the pushing operation.

In this embodiment, the position of the air cylinder 210 as the first restraint means is adjusted by the actuator. However, for example, the position for manually adjusting the position of the air cylinder 210 with respect to the moving die plate 51 is adjusted. It is also possible to adopt a configuration in which an adjusting mechanism is provided.

Further, although the mold clamping device in each of the above-mentioned embodiments is applied to the mold clamping of the die casting machine, the mold clamping device of the present invention is applicable not only to the die casting machine but also to a plastic injection molding machine or the like. It can be applied to other molding devices. Further, the mold clamping device described above,
Although the one using the toggle mechanism as the drive mechanism for driving the movable die plate has been described, the present invention is also applicable to a direct pressure type mold clamping device.

[0066]

According to the mold clamping device of the present invention, the extrusion pin can be reliably operated in cooperation with the opening / closing operation of the mold. Further, according to the mold clamping device of the present invention, the structure of the mold clamping device can be further simplified and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an example of a mold clamping device to which the present invention is applied.

FIG. 2 is a view for explaining the operation of the mold clamping device in FIG.

FIG. 3 is a plan view showing a configuration around a link housing and a movable die plate of the mold clamping device according to the embodiment of the present invention.

FIG. 4 is a rear view of the link housing 21.

5 is a cross-sectional view of the movable die plate 51 as seen from the direction of arrow D shown in FIG.

6 is a cross-sectional view of the link housing 21 as viewed in the direction of arrow E shown in FIG.

FIG. 7 is a diagram showing a state in which a movable die plate 51 has been moved to a mold open position PA.

FIG. 8 is a diagram showing a state in which a movable die plate 51 has been moved from a mold opening position PA to an extrusion position PB.

9 is a side view showing a state where the movable plate 53 of the link housing 21 is clamped to the link housing 21. FIG.

FIG. 10 is a plan view showing a configuration around a link housing and a movable die plate of a mold clamping device according to a second embodiment of the present invention.

FIG. 11 is a view for explaining the operation of the mold clamping device according to the second embodiment of the present invention.

FIG. 12 is a diagram for explaining the operation following FIG. 11.

FIG. 13 is a diagram for explaining the operation following FIG. 12.

FIG. 14 is a diagram for explaining the operation following FIG.

FIG. 15 is a view for explaining a modified example of the mold clamping device according to the second embodiment of the present invention.

FIG. 16 is a plan view showing a configuration around a link housing and a movable die plate of a mold clamping device according to a third embodiment of the present invention.

FIG. 17 is a view for explaining the operation of the mold clamping device according to the third embodiment of the present invention.

FIG. 18 is a diagram for explaining the operation following FIG. 17.

FIG. 19 is a cross-sectional view showing an example of the configuration of a conventional mold clamping device.

[Explanation of symbols]

1 ... Mold clamping device 21 ... Link housing 24 ... Clamping member 25 ... Air cylinder 51 ... Moving die plate 52 ... Moving mold 53 ... Movable plate 91 ... Fixed die plate 92 ... Fixed mold 95 ... Tie bar 100 ... base 110 ... Toggle mold clamping mechanism 210 ... Air cylinder 211 ... Piston rod

Claims (2)

[Claims] 1. A fixed die plate for holding a fixed mold,
A movable die plate for holding the movable die opposite to the fixed die; and a link housing provided with a drive mechanism for moving the movable die plate in the die opening / closing direction and supplying a die clamping force, A mold clamping device that opens and closes and clamps a mold, the movable member being connected to an extruding pin provided so as to be retractable from the movable mold and held by the movable die plate so as to be movable in a mold opening and closing direction. A first restraint unit provided on the movable die plate and releasably restraining the movable member at a predetermined position with respect to the movable die plate; When the movable member moves to the mold opening position, the movement of the movable member in the mold opening / closing direction is restricted, and the moving die plate is further moved toward the mold opening direction from the mold opening position.
Changing the position of the movable die plate when the restraint of the movable member is started by the second restraint means. A mold clamping device having a possible restraint position adjusting means. 2. The mold clamping apparatus according to claim 1, wherein the restraint position adjusting means has a position adjusting mechanism capable of changing a position of the first restraining means with respect to the movable die plate along a mold opening / closing direction.