JPH0759369B2 - Molding machine clamping device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a mold clamping device for a molding machine such as an injection molding machine, a die casting machine, or a press machine.

[Prior Art] FIG. 5 is a plan vertical cross-sectional view of an unknown mold clamping device according to Japanese Patent Application No. 63-114970. The prior art will be described with reference to FIG.

The mold clamping device shown in FIG. 5 includes a fixed plate 10, a movable plate 20, and a tie bar.
7, half nut 22, nut box 21, connecting plate 50, mold clamping cylinder 3, moving cylinder 2, fixed mold 30a, movable mold 30b, stopper box 33, compression spring 32, roller 36, stopper member 34, etc. Composed.

The fixed mold 30a is attached to a fixed platen 10 fixed on one end of the machine base 1, while the movable mold 30b is arranged on the other end side of the machine base 1 so as to face the fixed platen 10. Is attached to the movable plate 20. The tip of the piston rod 6 of the moving cylinder 2 fixed to the fixed platen 10 is attached to the movable platen 20, and can slide on the machine base 1 with respect to the fixed platen 10 to move back and forth. The tie bar 7 penetrating the movable plate 20 is provided with a plurality of tie bars 7 (four pieces in the present invention) each having the same overall length, one end of which is fixed to the internal piston 5 of the mold clamping cylinder 3, and the other. After the end penetrates the connecting plate 50 at a substantially right angle, it is fixed by tightening with a nut or end plate 51, and at the same time, the tie bar 7 and the connecting plate 50 are prevented from turning around the tie bar 7 using a key or the like. ing.
In addition, a half nut 22 to be described later is provided at a substantially middle portion of the tie bar 7.
A screw portion or a groove portion 8 is formed for engaging with the tie bar 7 by engaging with the movable plate 20. Further, a stopper surface 9a on the side of the fixed plate 10 perpendicular to the axial direction of the tie bar 7 and a non-fixed plate 10 are formed.
A concave portion 9 having a sloped surface 9b inclined toward the side is provided on the rear side of the screw portion or groove portion 8 of the tie bar 7.
The stopper member 34 of the stopper box 33 fixedly mounted on the movable plate 20 is constantly urged by the force acting toward the bottom of the recess 9, and the stopper member 34 descends the sloped surface 9b and enters the recess 9. Finally, the front surface of the stopper member 34 comes into contact with the vertical stopper surface 9a of the recess 9. The stopper means in the present invention comprises a stopper box 33, a compression spring 32, a stopper member 34, a shaft 31, a bush 35 and a roller 36. A shaft 31 is fixed in the axial direction of the stopper member 34 to the upper part of the stopper member 34 which is arranged so as to be vertically slidable in the stopper box 33.
Is slidably provided through a through hole formed in the upper part of the stopper box 33. On the other hand, the stopper member
A roller 36 is rotatably supported by a support shaft 36a at a lower portion of the roller 34. The roller 36 is always urged by a compression spring 32 in a direction substantially perpendicular to the axis of the tie bar 7 so that the roller 36 can move forward and backward. It is pressed against the tie bar 7 and is attached to the movable plate 20 so as to be movable back and forth in the axial direction of the tie bar 7. In addition, the nut box 21 fixed to the movable plate 20 has a half nut 22
And a hydraulic device (not shown) for a half nut for engaging or disengaging with a screw portion or groove portion 8 engraved in the tie bar 7 in a substantially right angle direction at the time of mold clamping is provided.

Next, the operation of the mold clamping device of the conventional example will be described.

As shown in FIG. 5, a movable plate is provided by supplying pressure oil to the piston rod chamber side 4a of the moving cylinder 2 during mold clamping.
The nut box 21 and the stopper box 33 fixed to the movable plate 20 and the movable plate 20 move along the tie bar 7 toward the fixed plate 10 in the axial direction. At this time, attach the spindle to the tip of the stopper member 34.
The roller 36, which is rotatably supported by the 36a, moves while rotating on the tie bar. First, the screw part or groove part 8 engraved in the substantially middle part of the tie bar 7 is inserted into the insertion hole of the movable plate 20.
It is smoothly inserted into 24. At this time, during the mold clamping operation, while the movable platen 20 is approaching the fixed platen 10 by the movable claw 2 in advance, the half nut 22 is quickly meshed with the screw part or the groove part 8 carved in the middle part of the tie bar 7. Since the operation is performed in parallel by the half nut hydraulic device, the nut box 21 fixedly installed adjacent to the movable plate 20 passes through the concave portion 9 of the tie bar 7, and then the stopper box.
The front surface of the stopper member 34, which is urged by the compression spring 32 from inside 33 and abuts against the stopper surface 9a of the recess 9 and locks the half nut 22 into the threaded portion or groove portion on the tie bar 7. It is possible to surely engage the gear 8 quickly. Also, when the meshing is completed, the movable plate mold is made by the mold clamping thin lid 3
The mold clamping of 30b and the fixed plate mold 30a is ready to start. In this state, since the pressure oil is continuously supplied to the piston rod chamber side 4a of the moving cylinder 2, the movable mold 30b
And the fixed mold 30a continues to move closer. Thereafter, by supplying pressure oil to the piston rod chamber side 5a of the mold clamping cylinder 3 fixed to the fixed platen 10, strong mold clamping can be started, and injection molding is performed in this mold clamping state.

[Problems to be Solved by the Invention] However, in the conventional apparatus, the movable platen 20 is fixed to the stationary platen 10 by supplying pressure oil to the stone rod chamber side 4a of the moving cylinder 2 during mold clamping.
While moving to the side, as described above, the roller 36 at the tip of the stopper member 34 starts to move on the sloped surface 9b of the recessed portion 9 of the tie bar 7 by being biased by the compression spring 32 from inside the stopper box 33. At this stage, the stopper member 34 is provided in a protruding manner, and the front surface portion thereof abuts against the stopper surface 9a to be locked, whereby the half nut 22
After engaging with the threaded portion or groove portion 8 on the tie bar 7, pressure oil was further supplied to the piston rod chamber side 4a of the moving cylinder 2 to lightly contact both dies, and then the die clamping operation was started.

Therefore, the locking points of the front surface of the stopper member 34 and the stopper surface 9a of the concave portion 9 on the tie bar 7 are constant with the movable mold 30b and the fixed mold 30a in contact with each other, that is, depending on the thickness of both molds. Therefore, a device for adjusting the die thickness is required, and the die clamping cylinder 3 needs to have a die thickness adjusting function.

Further, in the conventional apparatus, since the moving cylinder is fixed to the stationary platen side, the piston rod of the moving cylinder is always arranged in parallel with the tie bar at the peripheral portion of the mold, so that a person skilled in the art can use the metal rod. When working close to the mold, there are drawbacks such as being an obstacle or being easily scratched on the piston rod of the moving cylinder when the mold is attached or detached.

[Means for Solving the Problems] Therefore, according to the present invention, a fixed plate for holding a fixed mold having a plurality of mold clamping cylinders is fixed on one end of a machine base, and a movable plate for holding a movable mold. Is mounted on the other end of the machine base so as to be able to move forward and backward while facing the fixed plate, and one end of multiple tie bars penetrating the movable plate can be slidable in each mold clamping cylinder. The piston provided and the other end fixed to the connecting plate, the screw part is provided at the center of the tie bar in the axial direction, and the half nut that can be meshed with the screw part on the tie bar is movable. In a mold clamping device of a molding machine attached to a board, a moving cylinder for moving a movable board forward and backward toward a fixed board is arranged in mesh with the connecting plate, and the movable cylinder is meshed with the moving cylinder to move the cylinder forward and backward. The half nut and the thread or groove on the tie bar The screw mesh adjusting device that can be engaged is provided on the side opposite to the movable plate of the connecting plate.

[Operation] According to this configuration, the movable plate supplies pressure oil to the piston head chamber side of the movable cylinder at the stroke end of the movable cylinder before the movable mold and the fixed mold contact each other by the movable cylinder. Stop, and when pressure oil is supplied to the piston head chamber side of the half nut opening / closing cylinder to try to mesh the half nut with the screw part or groove part on the tie bar,
If the mold thickness of both the fixed mold and the movable mold is divided by the screw pitch of the half nut, and there is no fraction after the decimal point,
It is sufficient to engage the half nut with the thread or groove on the tie bar without activating the screw engagement adjusting device.In addition, if a fraction below the decimal point occurs, operate the screw engagement adjusting device. , Move to the position where the half nut and the screw or groove on the tie bar mesh, and after the half nut and the screw or groove on the tie bar completely mesh,
Pressure oil is supplied to the piston rod chamber side of the mold clamping cylinder to complete the mold clamping. Further, when the mold is opened, first, the pressure oil on the piston rod chamber side of the mold clamping cylinder is drained, and the pressure oil is supplied to the piston head chamber side.

Thus, by using a mold clamping cylinder having a small stroke and supplying a small amount of pressure oil to the piston head chamber side or the piston rod chamber side, mold clamping and mold opening can be easily performed.

[Embodiment] FIGS. 1 to 4 show an embodiment of the mold clamping device according to the present invention. FIG. 1 shows the stroke end stage of the moving cylinder 2 before the contact between the movable mold and the fixed mold. 2 is a plan vertical cross-sectional view in which the screw nut or groove on the tie bar is meshed with the half nut, FIG. 2 is an enlarged vertical cross-sectional view of the screw mesh adjustment device, and FIG. 3 is taken from line III-III in FIG. FIG. 3 (a) is a horizontal cross-sectional view of the tie bar locking device as viewed, in which pressure oil is supplied to the piston rod chamber side of the half nut opening / closing cylinder to release the mesh between the half nut and the tie bar. FIG. 3 (b) shows an operating state when pressure oil is supplied to the piston head chamber side of the half nut opening / closing cylinder to mesh the half nut with the tie bar. FIG. 4 is an enlarged vertical sectional view of the tie bar locking device.

Embodiments of the present invention will be described with reference to FIGS. 1, 2, 3, and 4.
It will be described with reference to the drawing.

The mold clamping device in FIG. 1 includes a fixed platen 10, a movable platen 20, a tie bar.
7, mold clamping cylinder 3, moving cylinder 2, fixed mold 30a, movable mold
30b, a half nut 22, a tie bar locking device 26, a screw mesh adjusting device 40 and the like.

The fixed mold 30a is attached to a fixed platen 10 fixed on one end of the machine base 1, while the movable mold 30b is arranged on the other end side of the machine base 1 so as to face the fixed platen 10. Is attached to the movable plate 20. Screws are formed on the outer circumference of the moving cylinder 2 on both sides of the connecting plate 50, and then inserted and arranged.
One end of the moving cylinder 2 is fixed by a cylinder connecting plate 41, the other end is attached to the movable plate 20 via the piston rod 6, and can move forward and backward by sliding on the machine base 1 with respect to the fixed plate 10. . Tie bar 7 that penetrates the movable plate 20
Are provided with a plurality (4 in the present invention) of the same diameter over the entire length, one end of which is fixed to the internal piston 5 of the mold clamping cylinder 3 and the other end is in a direction substantially perpendicular to the connecting plate 50. After being penetrated, the nut or end plate 51 is tightened and fixed, and at the same time, the tie bar 7 and the connecting plate 50 are prevented from turning around by using a key or the like.

At the approximate middle position of the tie bar 7, the movable platen 20 is meshed with a half nut 22 described later at the stroke end of the moving cylinder 2 before the movable mold 30b and the fixed mold 30a come into contact with each other during the mold closing operation. A screw portion or a groove portion 8 for locking the tie bar 7 is formed.

The screw mesh adjusting device 40 will be described with reference to FIG.
The screw mesh adjusting device 40 is arranged on the side opposite to the movable plate 20 of the connecting plate 50, and meshes with the screw portion 27 formed on the outer peripheral portion of the moving cylinder 2 via the drive nut 18. Then, before the two molds come into contact with each other by the mold closing operation, pressure oil is supplied to the piston head chamber side 15a of the half nut opening / closing synrider 14 of the diver locking device 26 in the state of the stroke end of the moving cylinder 2. It is used when meshing is not possible even when trying to mesh with the threaded portion or groove portion 8 engraved on the tie bar 7.

That is, a screw portion 27 is engraved on the outer peripheral portion of the moving cylinder 2, the screw portion 27 and the drive nut 18 of the screw engagement adjusting device 40 are engaged with each other, and a part of the connecting plate 50 is engraved. To L
The drive nut 18 is configured to be rotatable by abutting one end of the drive nut 18 having a letter shape and further pressing the nut with a nut retainer 17 to bring it into contact therewith.

Further, the other end of the drive nut 18 is on the side opposite to the connecting plate 50, and has a sprocket portion 19 on the outer peripheral portion of the drive nut 18.
Rotation prevention of the key 28 and the like is used to prevent rotation with the drive nut 18, and a holding plate 29 is attached to the side surface portion to prevent the sprocket portion 19 from falling off.

The sprocket portion 19 is connected by a chain (not shown), a sprocket that is integrated with an output shaft of a motor (not shown) is connected to the chain, and the chain is driven by the rotation of the motor to drive the drive nut 18 in the axial direction of the tie bar 7.
By moving back and forth, the movable platen 20 and the moving cylinder 2 arranged so as to penetrate the tie bar 7 in a direction substantially perpendicular to the tie bar 7 can be moved back and forth. Further, a bush 52 is attached to an insertion hole portion between the movable plate 2 and the connecting plate 50.

Next, referring to FIGS. 3 and 4, the tie bar locking device 26 will be described.
Will be explained.

The tie bar locking device 26 includes a half nut opening / closing cylinder 14, a piston 15, a piston rod 23, a half nut 22, a connecting rod 101, and stoppers 102 and 103.

The half nut 22 is provided adjacent to the movable plate 20 and is provided with a tie bar 7.
Each half has a pair of half nuts 22 that are vertically divided into two parts, and the piston rod 2 is provided on the end face of the half nut 22a on the non-meshing side.
One end of 3 is stuck. Further, a piston 15 that engages with the half nut opening / closing cylinder 14 and slides vertically is disposed at the other end of the piston rod 23, and an adjusting plate 100 is fixed to the lower end of the half nut opening / closing cylinder 14. With half nut 22a
The connecting rod 101 connected through 22b is the piston rod 23.
The connecting rod 101 is fixed to the adjusting plate 100 at one end, and the other end is fixed to the half nut 22b. Then, as shown in FIG. 3 (a), by supplying pressure oil to the piston rod side chamber 15b of the half nut opening / closing cylinder 14, the piston 15 is pushed up and the half nut opening / closing cylinder 14 is pushed downward. It is lowered, and a pair of upper and lower half nuts 22a and 22b move while sliding on the nut box 21 to release the meshed state of the half nut 22 and the tie bar 7, and stop by contacting the stoppers 102 and 103, respectively. Is supposed to do. When the half nut 22 is to be engaged with the tie bar 7, as shown in FIG. 3 (b),
Piston head side chamber 15 of the half nut opening / closing cylinder 14
By supplying pressure oil to a, the piston 15 is pushed down and the half nut opening / closing cylinder 14 is pushed upward, and the half nuts 22a and 22b slide in the nut box 21 and move toward the tie bar 7 direction. Then, finally, they are brought into contact with each other to be meshed with the tie bar 7.

Next, the operation of the mold clamping device of the present invention thus constructed will be described.

In the mold clamping device configured as described above, pressure oil is supplied to the piston head chamber side 4b of the moving cylinder 2 at the time of mold closing, so that the movable platen 20 and the tie bar locking device 26 fixed to the side surface of the movable platen 20. Move to the fixed platen 10 side in the axial direction of the tie bar 7 together. First, the screw portion or the groove portion 8 engraved in the substantially middle portion of the tie bar 7 is smoothly inserted into the insertion hole 24 of the movable plate 20, and the movable plate 20 is further moved forward. Before the stationary die 30a and the stationary die 30a slowly contact with each other, the supply of the pressure oil to the piston head chamber side 4b of the moving cylinder 2 is stopped at the stroke end of the moving cylinder 2.

Next, the half nut 22 starts to mesh with the thread portion or the groove portion 8 on the tie bar 7. First, the half nut opening / closing cylinder 14
When pressure oil is supplied to the piston side chamber side 15a inside through a pipe (not shown), the half nut 22 advances in a direction substantially perpendicular to the tie bar 7. Here, for example, when the die height is changed by exchanging both molds of the movable mold 30b and the fixed mold 30a, the molds of both molds when the movable mold 30b and the fixed mold 30a are contacted in advance. When the thickness (die height) H is measured with a scale and this is divided by the pitch P of the threaded portion or groove portion 8 on the tie bar 7 (H / P), here, if it is divisible, the fraction below the decimal point is If it does not occur, if pressure oil is supplied to the piston head chamber side 15a of the half-nut nut opening / closing cylinder 14 at the stroke end of the moving cylinder 2 before the two molds come into contact with each other, the half-nut 22 will move above the tie bar 7. Completely meshes with the threaded portion or groove portion 8 of the above. However, conversely to the above, when the H / P is not divisible and a fraction less than the decimal point occurs, the pitch of the threaded portion or groove 8 on the tie bar 7 (or the half nut) The value obtained by multiplying the screw pitch P of 22 is the half nut 22 and tie bar 7
The moving distance A is for completely engaging the upper screw portion or groove portion 8. That is, in order to drive the screw mesh adjusting device 40 by an amount commensurate with the moving distance A and completely mesh the screw portion or groove portion 8 on the tie bar 7 with the half nut 22, the motor connected by the chain is rotated. The sprocket 19 is rotated to move the moving cylinder 2 backward.
However, the rotation of the motor can be measured by a pulse and converted into a moving distance for the moving cylinder 2 to move backward. In this way, the screw nut or groove 8 on the tie bar 7 is halved.
It is possible to completely engage 22.

When the meshing is completed, the mold clamping of the movable plate mold 30b and the fixed plate mold 30a by the mold clamping cylinder 3 is ready to start. Thereafter, by supplying pressure oil to the piston rod chamber side 5a of the mold clamping cylinder 3 fixed to the fixed platen 10, it is possible to start the mold clamping strongly. Injection molding is performed in this mold clamped state.

When the mold is opened, first, the pressure oil on the piston rod chamber side 5a of the mold clamping cylinder 3 is released and withdrawn, and at the same time, when the pressure oil is supplied to the piston head chamber side 5b, the piston 5 moves backward. The mold opening will be started.

In the present invention, as shown in FIG. 1, it is necessary to engrave a screw portion or groove portion 8 on the tie bar 7 longer than in the conventional example shown in FIG. 5, and both molds contact each other regardless of the mold thickness. At the stroke end of the moving cylinder 2 on the front side, the mold clamping operation is started by the mold clamping cylinder 3 from the state where the threaded portion or groove 8 of the tie bar 7 and the half nut 22 are meshed. It's short.

Further, a gear may be used instead of the sprocket 19 shown in FIG.

Regarding the die height H, the case of measuring with a scale was described, but a scale sensor for automatically detecting the die height H is arranged, and this data is automatically input to the computer, and the tie bar 7 input in advance is input. Of the sprocket so that the half nut 22 and the screw portion or groove portion 8 on the tie bar 7 are completely meshed with each other when the H / P is not divisible, as described above. The required pulse is issued to the motor connected with 19 via the chain by the command from the computer, and the sprocket corresponding to this is issued.
19 may be rotated so that the moving cylinder 2 may be moved so as to move backward for a required moving distance A, and if the H / P is split, the half nut 22 and the threaded portion or groove portion 8 on the tie bar 7 and the corresponding portion thereof. A command may be issued from the computer to supply pressure oil to the piston head chamber side 15a in the half nut opening / closing cylinder 14 for engagement in the field, or may be manually performed. In the present embodiment, the moving cylinders 2 are provided on the left and right sides of the connecting plate 50, but the present invention is not limited to this, and the connecting plate 50
It may be provided on the diagonal of 50 or above and below.

[Effects of the Invention] As described above, according to the present invention, regardless of the size of the mold, the movable platen is entirely moved by the moving cylinder, and only the final mold clamping is performed by the mold clamping cylinder. The stroke is shorter than that of the mold clamping cylinder of the machine, and less hydraulic oil is required.

If the stroke of the mold clamping cylinder is short (volume is small), the amount of compressed oil is reduced and the time for generating the mold clamping force is shortened.

For this reason, since the amount of pressure oil is small, the pressure oil supply device becomes small, the manufacturing cost of the mold clamping cylinder becomes low, and the molding cycle of the product becomes short.

Further, in the conventional device, since the moving cylinder is fixed to the stationary platen side, the piston rod of the moving cylinder is always arranged in parallel with the tie bar at the peripheral portion of the mold, and therefore, those skilled in the art can easily use the mold. It was easy to get in the way when working close to, or it was easy to scratch the piston rod of the moving cylinder at the time of attaching and detaching the mold, but in the present invention, the moving cylinder is not fixed to the movable plate. Since it is provided on the panel side, there is no such drawback of the related art, and the workability and safety are improved without the piston rod getting in the way.

[Brief description of drawings]

1 to 4 show an embodiment of a mold clamping device according to the present invention. FIG. 1 shows a screw on a tie bar at a stroke end stage of a moving cylinder before a movable mold and a fixed mold come into contact with each other. Section or groove and a plan vertical sectional view for engaging a half nut, FIG. 2 is an enlarged vertical sectional view of a screw mesh adjusting device, and FIG. 3 is a tie bar locking seen from line III-III in FIG. FIG. 3A is a horizontal cross-sectional view of the apparatus, and FIG. 3A shows a case where pressure oil is supplied to the piston rod chamber side of the half nut opening / closing cylinder to release the meshing of the half nut and the tie bar. (B) shows an operating state when pressure oil is supplied to the piston head chamber side of the half nut opening / closing cylinder to engage the half nut with the tie bar. FIG. 4 shows an enlarged vertical sectional view of the tie bar locking device. Further, FIG. 5 is a plan vertical sectional view showing an example of a conventional device similar to the present invention. 1 ... Machine base, 2 ... Moving cylinder, 3 ... Mold clamping cylinder, 4,5 ... Piston, 6 ... Piston rod, 7
...... Tie bar, 8 ...... screw or groove, 10 ...... fixing board,
14 …… Half split nut open / close cylinder, 18 …… Drive nut, 19
...... Sprocket part, 20 ...... Movable plate, 21 ...... Nut box, 22 ...... Half-nut, 26 ...... Tie bar locking device, 30a
...... Fixed mold, 30b ...... Movable mold, 40 ...... Screw mesh adjustment device, 50 ...... Connecting plate.

Claims (1)

[Claims] 1. A fixed plate for holding a fixed mold having a plurality of mold clamping cylinders is fixed on one end of a machine base, and a movable plate for holding a movable mold is provided on the other end side of the machine base. It is placed so that it can move forward and backward while facing the fixed plate, and one end of multiple tie bars that penetrate the movable plate is provided slidably in each mold clamping cylinder on the piston part and the other end. Is fixed to the connecting plate, a screw part or groove part is provided at substantially the center of the tie bar in the axial direction, and a half nut that can be meshed with the screw part or groove part on the tie bar is attached to the movable plate. In the mold clamping device, a moving cylinder for moving the movable plate forward and backward toward a fixed plate is arranged in mesh with the connecting plate, and the movable cylinder is meshed with the movable cylinder to move the cylinder back and forth to move the half nut and the tie bar on the tie bar. A screw meshing tone that can mesh with a screw part or groove part Molding machine mold clamping device provided in the counter movable platen side of the device coupling plate.