JPH05169454A - Clamping device of molding machine - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce the space occupied by the approach cylinder device and make it a compact mold clamping device. [Structure] The approach cylinder device is installed inside the tie bar, and its telescopic rod is fastened to the movable plate or fixed plate so that it can go in and out from the tip of the tie bar, and there is an engaging / disengaging means between the tie bar and the movable plate or fixed plate. Provided.

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 for a molding machine, and more particularly to a mold clamping device used for an injection molding machine, a die casting machine, a press molding machine or the like.

[0002]

2. Description of the Related Art Generally, in an injection molding machine, a die casting machine, or a press molding machine, a fixed mold and a moving mold are brought close to each other to perform mold matching, and thereafter, mold clamping is performed by a mold clamping cylinder device. There is. In order to perform this mold clamping operation, a fixed plate to which a mold is attached and a movable plate are connected by a tie bar, and one end of the tie bar constitutes a mold clamping cylinder device.

By the way, the operations to be applied to the mold are a movement for mold matching which does not require a pressing force and a mold clamping operation which requires a strong pressing force for clamping, and both operations are a mold clamping cylinder device. Therefore, an approach cylinder device (also referred to as a moving cylinder or a boost cylinder device) for performing a movement for mold matching is usually provided separately from the mold clamping cylinder device because the hydraulic device becomes large in size. As a result, the mold fitting operation with a long moving stroke is performed by the approach cylinder device, and after the mold matching, the mold clamping cylinder device performs mold clamping that requires a strong reduction force.

Conventionally, an approach cylinder device in such a mold clamping device is constituted by a cylinder device having a small cross section and long stroke, which connects a fixed platen and a movable platen, as disclosed in Japanese Patent Publication No. 51-29978. This is arranged in parallel with the tie bar, and the movable platen is moved toward the fixed platen by the stroke of the piston rod. At this time, the tie bar functions as a guide shaft. Usually, in order to fix the position of the tie bar and the movable plate at the mold matching position, a split nut means is provided on the movable plate side and a groove is formed on the tie bar side.
A split nut is fitted in the groove of the tie bar at the mold matching position for positioning, and then a mold clamping pressure is applied by a mold clamping cylinder device.

[0005]

However, in the conventional mold clamping device, the approach cylinder device has a long stroke structure that covers the strokes of the fixed platen and the movable platen, and is arranged in parallel with the tie bar. Because
There is a drawback that the space occupied by the approach cylinder device becomes large and the device becomes large.

An object of the present invention is to provide a compact and space-saving mold clamping device by focusing attention on the above-mentioned conventional problems and effectively disposing an approach cylinder device for mold matching. Especially.

[0007]

In order to achieve the above object, in a mold clamping device of a molding machine according to the present invention, a fixed plate to which a fixed mold is mounted and a movable plate to which a movable mold is mounted are connected by a tie bar. In the mold clamping device of the molding machine, the movable platen is moved to the mold clamping position by the approach cylinder device with respect to the fixed platen, and the mold clamping is performed by the mold clamping cylinder device. The approach cylinder device is incorporated into the above, and its telescopic rod is fastened to the movable platen or the fixed platen so as to be able to move in and out from the tip of the tie bar, and the engaging / disengaging means is provided between the tie bar and the movable platen or the fixed platen.

[0008]

According to the above construction, the approach cylinder device is incorporated in the inside of the tie bar, and the telescopic rod projecting from the tip of the tie bar expands and contracts, whereby the entire length of the tie bar expands and contracts. With this, the movable plates connected to each other can be moved to the mold matching position. Since the tie bar penetrates the movable plate at the mold matching position, it is sufficient to position the tie bar in this state by the engaging / disengaging means and perform the mold clamping pressure reduction by the mold clamping cylinder. In such a configuration, since the tie bar and the approach cylinder device are integrated, it is possible to significantly reduce the space as compared with the case where the approach cylinder device is installed outside the tie bar, and the entire mold clamping device can be constructed. The structure can be downsized.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A concrete embodiment of a mold clamping device of a molding machine according to the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view of a molding machine such as an injection device equipped with a mold clamping device according to the embodiment. As shown in this figure, the molding machine mounts a fixed mold 10 and a movable mold 12 on a fixed platen 14 and a movable platen 16, respectively. The fixed platen 14 is fixed to a base (not shown), while the movable platen 16 is slidably installed on the base and can move toward and away from the fixed platen 14. Four tie bars 18 are attached to the four corners of the outer edge of the fixed platen 14 and the movable platen 16 in order to support the movement guide of the movable platen 14 and the pressing force at the time of mold clamping. Tie bar 1
One end of the fixed plate 8 is fixed to a support plate 20 arranged on the back surface of the fixed platen 14, penetrates the fixed platen 14 to reach the movable platen 16, and the tip is inserted and connected to the movable platen 16.

To attach the tie bar 18 to the support plate 20, as shown in detail in FIG. 2, a screw 22 is engraved on the outer periphery of the end portion of the tie bar 18, and a drive nut 24 is screwed onto the screw 22. , The drive nut 24 to the support plate 20
The tie bar 18 is prevented from moving in the axial direction by being attached to the. The drive nut 24 is the support plate 20.
It is housed inside from the back side of, and is held in a fixed position by the holding plate 26, and is rotatable at the fixed position. A chain sprocket 28 is attached to the outer end surface of the drive nut 24, and the drive chain 30 is attached to the chain sprocket 28 attached to the drive nuts 24 corresponding to the four tie bars 18, as shown in FIG. It is designed so that it can be hung and rotated at the same time. By this, the position of the support plate 20 is adjusted according to the height dimension of the molds 10 and 12 at the time of mold matching, that is, the so-called die height, and the stroke of the mold clamping cylinder device provided between the support plate 20 and the fixed platen 14 is fixed. To be able to hold.

On the other hand, the tip end of the tie bar 18 is inserted into the movable platen 16. For this reason, the movable platen 16 has a tie bar insertion hole 32 formed therein. Further, in the mold clamping device of this embodiment, the approach cylinder device 34 is integrally incorporated in the tie bar 18, and the device 34 and the movable platen 16 are directly connected. That is, as shown in detail in FIG. 2, the inside of the central portion of the tie bar 18 is cut out to form a cylinder tube 36, and a piston 38 is slidably mounted inside the cylinder tube 36. The piston 38 is provided with a long rod 40 directed to the movable platen 16 side, which is projected from the end surface of the tie bar 18, and the protruding tip is fixed to the movable platen 16. Inside the cylinder tube 36, head-side and rod-side hydraulic chambers 42A and 42B partitioned by the piston 38 are formed, and the hydraulic chambers 42A and 4B are formed.
2B can be supplied with pressure oil from a hydraulic source (not shown). Therefore, when the pressure oil is supplied to the head side hydraulic chamber 42A, the piston rod 40 projects from the tip of the tie bar 18, and pushes out the movable platen 16 connected to the piston rod 40 to separate the fixed platen 14 from the fixed platen 14, thereby performing a mold opening operation. On the contrary, by supplying pressure oil to the rod side hydraulic chamber 42B, the rod 28 is drawn into the tie bar 18 and moved, and the movable platen 16 is moved forward to the mold matching position.
The stroke end of the piston 38 in the cylinder tube 36 is set so as to correspond to the mold opening position and the mold matching position, respectively.

When the approach cylinder device 34 is extended and driven, the molds 10 and 12 are moved to the mold open position, and conversely, when the contracted and driven, the molds are brought into a mold matching state. It is necessary to make it free in the open state, and to connect and fix both in the mold matching state. For this reason, the disengagement means 44 is incorporated in the movable platen 16. This is a tie bar 1 as shown in FIG.
An engaging groove 46 is formed on the outer periphery of the groove 8, and a pair of thrust plates 48 are disposed so as to be able to be fitted into and removed from the engaging groove 46. The pair of thrust plates 48 are arranged on the same plane orthogonal to the tie bar 18, one end of the thrust plate 48 faces the outer peripheral surface side of the tie bar 18, and the other end of the thrust plate 48 extends inside. Face the surface side. The thrust plates 48 are arranged so that they can move in parallel, and they are connected by a link plate 50.
Are rotated by the cylinder mechanism 51 so that they can be translated in opposite directions. This engagement / disengagement mechanism is formed at both ends of the thrust plate 48, and can be engaged / disengaged with the pair of tie bars 18 at the same time. Further, the engagement / disengagement mechanism is formed symmetrically with the cylinder mechanism 51 sandwiched therebetween, and simultaneously engages / disengages the four tie bars 18.

By the way, the molds 10 and 1 which are matched with each other.
The mold clamping cylinder device 52 for clamping the mold 2 is provided between the support plate 20 and the fixed platen 14, and is vertically arranged in a pair on the vertical line passing through the center of the mold, as shown in FIG. There is. This is a cylinder portion 54 formed in the fixed platen 14.
And a ram 56 provided on the support plate 20 are slidably fitted together, and a mold clamping force is generated by supplying pressure oil from a hydraulic source (not shown).

According to the mold clamping device of the molding machine configured as described above, the movable platen 16 is moved away from the fixed platen 14 by extending and driving the approach cylinder device 34 incorporated in the tie bar 18. Opening is done. The mold clamping operation is performed by the rod side hydraulic chamber 4 of the built-in approach cylinder device 34.
2B by supplying pressure oil to the piston 3
8 moves to the stationary platen 14 side, the end portion of the tie bar 18 enters the insertion hole 32, and the piston 38 reaches the stroke end to reach the mold matching position. At this position, the thrust plate 48 incorporated in the movable plate 16 and the engagement groove 46 formed in the tie bar 18 are aligned, and the cylinder mechanism 50 for operation is driven to fit the thrust plate 48 into the engagement groove 46. ,
The positioning of the movable plate 16 and the tie bar 18 is completed. After that, by supplying pressure oil to the mold clamping cylinder device 52, the pressing force is transmitted to the movable platen 16 via the support plate 20, the drive nut 24, the tie bar 18, and the engaging / disengaging means 44, so that the molds 10 and 12 are separated. The mold is clamped.

According to this structure, the approach cylinder device 34 having a long stroke is incorporated in the tie bar 18 to move the movable platen 16, and the movable platen 1 is clamped at the time of mold clamping.
Since the 6 and the tie bar 18 are connected by the engagement / disengagement means 44, the mold clamping cylinder device 52 is driven.
It is possible to perform mold opening and mold matching without hindering the mold clamping of the molds 10 and 12. Therefore, the space occupied by the approach cylinder device 34 can be significantly reduced, and the size of the mold clamping device can be reduced.

Next, FIG. 4 shows a second embodiment. This is an approach cylinder device 3 with a tie bar built into the fixed platen 14.
The tie bar 18 is connected to the movable platen 16 via the drive nut 24.
Further, the mounting state of the built-in approach cylinder device 34 is opposite to that of the first embodiment. According to this, by the extension drive of the approach cylinder device 34, the movable platen 16 including the tie bar 18 is moved leftward in the drawing, and the mold opening is performed.

Also in this embodiment, since the approach cylinder device 34 is built in, a compact mold clamping device can be similarly obtained.

In these embodiments, the position of the thrust plate 48 is determined because the mold matching position is limited by the stroke end of the piston 38 of the approach cylinder device 34 and the butting end of the tie bar 18 into the insertion hole 32. There is an advantage that it can be set surely and easily.

In the above embodiment, the tie bar 18 and the movable platen 16 or the fixed platen 14 are positioned by the thrust plate 48. However, this can be done by the split nut means which has been conventionally used, and this is also possible. It is also possible to connect and fix by means similar to the above.

[0021]

As described above, in the mold clamping device of the molding machine according to the present invention, the approach cylinder device is incorporated in the tie bar, and its telescopic rod is fastened to the movable plate or the fixed plate to move in and out from the tip of the tie bar. Since it is possible and the engaging / disengaging means is provided between the tie bar and the movable platen or fixed platen, it is possible to reduce the size by effectively disposing the approach cylinder device for mold matching. -A space-saving mold clamping device can be used.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a molding machine including a mold clamping device according to an embodiment.

FIG. 2 is a sectional view of a main part of the mold clamping device according to the embodiment.

FIG. 3 is a side view of the mold clamping device according to the embodiment and an explanatory view of the engagement / disengagement means.

FIG. 4 is a cross-sectional view of a molding machine including a mold clamping device according to a second embodiment.

[Explanation of symbols]

 10 Fixed mold 12 Movable mold 14 Fixed plate 16 Movable plate 18 Tie bar 20 Support plate 22 Screw 24 Drive nut 26 Holding plate 28 Chain sprocket 30 Drive chain 32 Tie bar insertion hole 34 Approach cylinder device 36 Cylinder tube 38 Piston 40 Rod 42A, 42B Hydraulic chamber 44 Engaging means 46 Engaging groove 48 Thrust plate 50 Link plate 51 Cylinder mechanism 52 Clamping cylinder device 54 Cylinder part 56 Ram

Claims (1)

[Claims] 1. A fixed plate to which a fixed mold is attached and a movable plate to which a movable mold is attached are connected by a tie bar, and the movable plate is moved to a mold clamping position by an approach cylinder device with respect to the fixed plate, In a mold clamping device of a molding machine configured to perform mold clamping with a mold clamping cylinder device, an approach cylinder device is incorporated in the inside of the tie bar, and its telescopic rod is fastened to a movable plate or a fixed plate to move in and out from the tip of the tie bar. A mold clamping device for a molding machine, which is capable of being provided with engaging / disengaging means provided between a tie bar and a movable platen or a fixed platen.