JPH0321408A - Mold clamping device of molding machine - Google Patents

Abstract

PURPOSE:To enable easily mold clamping and mold break with feed of a small quantity of hydraulic oil by making use of a small mold clamping cylinder, by a method wherein a movable large stroke moving device moving forward and backward the movable platen to and from a stationary platen is provided between a connecting plate and the movable platen and a screw engagement regulating device is provided on the connecting plate and a movable platen large stroke moving device part. CONSTITUTION:Feed of hydraulic oil to a piston head chamber side 4b of a movable cylinder 2 is suspended at a stroke end of the movable cylinder 2, which is of this side where a movable mold 30b and stationary mold 30a come into contact with each other. Then, the hydraulic oil is fed to a piston head chamber side 15a in an opening and closing cylinder 14 of a semisplit nut. When a fraction not exceeding a decimal point is not generated on H/P obtained by dividing mold thickness H of both the molds such as the movable molds 30b and stationary mold 30a with a pitch P of a screw part of a groove part 8 on a tie bar 7, the semisplit nut 22 is engaged completely with the screw part or the groove part 8 on the tie bar 7. When the fraction not exceeding the decimal point is generated, the semisplit nut 22 and the screw part of the groove part 8 on the tie bar 7 are moved for engagement by actuating a screw engagement regulating device 40.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application 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 vertical cross-sectional plan view of an unknown mold clamping device according to Utility Application No. 114970/1983, and the prior art will be explained using Fig. 5. The mold clamping device in FIG. 5 includes a fixed platen 10, a movable platen 20,
Tie bar 7, half nut 22, nut box 21, connecting plate 50, mold clamping cylinder 3, moving cylinder 2, fixed mold 3
0a, movable mold 30b, stopper box 33, compression spring 32. Roller 36. It consists of a stopper member 34 and the like. The fixed mold 30a is fixed to one end L of the machine base L! ! ? On the other hand, a movable mold 30b is attached to the movable platen 20 on the other end side of the machine base L, facing the fixed m10. The tip of the piston rod 6 of the movable cylinder 2 fixed to the fixed platen 10 is attached to the movable platen 20, and can move forward and backward relative to the fixed platen 10 by sliding on the machine base l. The tie bars 7 that penetrate the movable platen 20 are provided with a plurality of tie bars (four in the wooden invention) manufactured to have the same overall length and the same diameter, one end of which is fixed to the internal piston 5 of the mold clamping cylinder 3, and the other end is fixed to the internal piston 5 of the mold clamping cylinder 3. After the end penetrates the connecting plate 50 in a direction substantially perpendicular to it,
At the same time that the tie bar 7 and the connecting plate 50 are tightened and fixed with nuts or end plates 51, the tie bar 7 is prevented from rotating using a key or the like. Further, a threaded portion or a groove portion 8 is formed approximately at the middle portion of the tie bar 7 in order to engage with a half nut 22 to be described later to lock the movable platen 20 to the tie bar 7. A recess 9 having a stopper surface 9a on the fixed platen 10 side perpendicular to the fixed platen 10 and a sloped surface 9b inclined toward the anti-fixed platen 10 side is provided on the rear side of the threaded portion or groove portion 8 of the tie bar 7. ．．
The stopper member 34 of the stopper box 33 fixed to the movable platen 20 is constantly biased with a force that acts toward the bottom of the recess 9, and the stopper member 34 descends down the slope 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 includes a stopper box 33, a compression spring 32, a stopper member 34, and a shaft 3.
1. It is composed of a pusher 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 to be able to slide vertically within the stopper box 33. It is provided so that it can slide freely through the hole. On the other hand, at the lower part of the stopper member 34, a roller 36 is rotatably supported on a support shaft 36a, and the roller 36 is biased by a compression spring 32 in a direction substantially perpendicular to the axis of the tie bar 7. I'm always moving forward and backward at the same time as Taipa 7.
It has a structure that allows it to move freely back and forth in the axial direction of the tie A7 along with the movable IB20. Also,
A nut box 21 fixed to the movable platen 20 is equipped with a half nut 22, which is used to engage or disengage the threaded part or groove part 8 carved in the tie bar 7 in a substantially perpendicular direction during mold clamping. Oil adjustment device for half nuts (not shown)
was set up. Next, the operation of the conventional mold clamping device will be explained.

As shown in FIG. 5, the movable platen 20 and the nut box 2 fixed to the movable platen 20 by supplying pressure oil to the piston rod chamber side 4a of the movable cylinder 2 during mold clamping.
1 and the stopper box 33 are attached to the fixed plate 1 along the tieper 7.
Move to the 0 side in the axial direction. At this time, stopper member 3
A roller 36, which is rotatably supported on a support shaft 36a at the tip of 4, moves while rotating the tie/<11. The threaded portion or groove portion 8 is smoothly inserted into the insertion hole 24 of the movable platen 20 6 At this time, in advance, when the movable platen 20 is approaching the fixed platen 10 by the movable cylinder 2 during the mold clamping operation, the half nut 22 is inserted. Since the action of quickly engaging the threaded part or groove part 8 carved in the approximately middle part of the tie bar 7 is simultaneously performed by the half-nut hydraulic system, the nut fixedly installed adjacent to the movable a20 is The box 2l passes through the recess 9 of the tie/height 7, and then the stomper member 3 drilled by being biased by the compression spring 32 from inside the stopper box 33
By abutting and engaging the i11 surface portion of 4 with the stopper surface 9a of the recess 9, it is possible to reliably engage the half nut 22 with the threaded portion or groove portion 8 of the tieper 7L. Further, when the engagement is completed, the clamping of the movable platen mold 30b and the fixed platen mold 30a by the mold clamping sill 3 is ready to start. In this state, since oil continues to be supplied to the piston rod chamber side 4a of the movable cylinder 2, the movable mold 30b and the fixed mold 30a continue to move closer together. After that, by supplying pressure oil to the piston rod chamber side 5a of the mold clamping cylinder 3 fixedly installed on the fixed platen 10, strong clamping can be started, and injection or molding can be carried out in this clamped state. .

[Problems to be Solved by the Invention] However, in the conventional device, pressure oil is supplied to the stone rond chamber side 4a of the movable cylinder 2 during mold clamping, and while the movable platen 20 is being moved to the fixed platen 10 side, as described above, Stopper box 3
The roller 36 at the tip of the stomper member 34 is pushed by the compression spring 32 from inside the tie bar 7 into the recess 9 at the approximately middle portion of the tie bar 7.
At the stage when the stopper member 34 starts to move on the slope surfaces 9b, l, the front part abuts and locks against the stopper surface 9a. After engaging the groove portion 8, oil was further supplied to the piston rod chamber side 4a of the movable cylinder 2, and after the two molds were brought into light contact, the mold wI operation was started.

Therefore, when the movable mold 30b and the fixed mold 30a are in contact with each other, that is, the two molds are compressed, the locking point between the front surface of the stopper member 34 and the stopper surface 9a of the recess 9 on the tie bar 7 is constant. Therefore, a device to adjust the mold thickness was required, and the mold clamping cylinder 3 had to have a Seijun adjustment function. In addition, in the conventional device, since the movable cylinder was fixed to the fixed platen side, the piston rows and dors of the movable cylinder were always disposed parallel to the tie bar around the mold. may get in the way when working close to the mold, or may interfere with the installation or installation of the mold.
This eliminates drawbacks such as the piston rond of the moving cylinder being easily scratched when removed. [Means for Solving the Problem] Therefore, in the present invention, a fixed plate for holding a fixed mold that holds a plurality of mold clamping cylinders is fixed on one end of the machine base, and a movable plate for holding a movable mold is fixed on one end of the machine base. The platen is placed on the other end of the machine base facing the fixed platen so that it can move forward and backward, and one end of the multiple tie bars that pass through the movable platen can be slid inside each mold clamping cylinder. A half nut is attached to the piston part provided on the tie bar, and the other end is fixed to the connecting plate, a threaded part is provided at approximately the center in the axial direction of the tie bar, and the half nut is provided so as to be able to engage with the threaded part on the tie bar. Model #l of the molding machine attached to the movable plate! In the device, a movable plate large stroke moving device for moving the movable plate back and forth toward the fixed plate is provided between the connecting plate and the moving plate, and a screw alignment adjustment device is provided on the connecting plate and the movable plate large stroke moving device. I made a plan.

[Function] According to this structure, the movable platen supplies the right sleeve to the piston hand chamber side of the movable cylinder at the stroke end of the movable cylinder before the movable mold and the fixed mold come into contact with each other by the movable cylinder. When trying to stop the half nut and supply pressure oil to the piston head chamber side of the half nut opening/closing cylinder to engage the half nut with the threaded part or groove on the tie bar,
If there is no fraction after the decimal point when dividing the mold length of both the fixed mold and the moving mold by the thread pitch of the half nut,
Simply engage the half nut and the threaded part or groove of the tie bar E without operating the screw engagement adjusting device.Also, if there is a fraction after the decimal point, use the screw engagement adjustment device. After operating the half nut and the threaded part or groove of the tie bar L to the position where they fit together, and after the half nut and the threaded part or groove of the tie bar L are completely engaged, move the half nut and the tie bar L to the piston rod chamber side of the mold clamping cylinder. Supply pressure oil to complete mold clamping. Furthermore, when opening the mold, this is accomplished by first removing the pressure oil from the piston head chamber side of the mold clamping cylinder, and then supplying oil to the piston head chamber side. In this way, mold clamping and mold opening can be easily performed by using a mold clamping cylinder with a small stroke and by supplying a small amount of pressure oil to the piston head chamber side or piston rod chamber side. [Embodiment] Figures 1 to 4 show an embodiment of the mold clamping device according to the present invention, and Figure 1 shows the stage of the stroke end of the movable cylinder 2 before the movable mold and the fixed mold come into contact. Fig. 2 is an enlarged longitudinal sectional view of the screw engagement adjustment device, and Fig. 3 is taken from the 1m line in Fig. 1. FIG. 3(a) is a plan cross-sectional view of the tie bar locking device as seen, and FIG. 3(a) shows the case where pressure oil is supplied to the piston rod chamber side of the half nut opening/closing cylinder to release the engagement between the half nut and the tie bar. , 0'S3 figure (
b) shows the operating condition when pressure oil is supplied to the piston head chamber side of the half-nut opening/closing cylinder and the half-nut and tie bar are engaged. Furthermore, Fig. 4 shows an enlarged longitudinal sectional view of the tie bar locking device. Embodiments of the present invention will be explained with reference to FIGS. 1, 2, 3, and 4. The mold clamping device in Fig. 1 includes a fixed filO, a movable platen 20
, tie bar 7, mold clamping cylinder 3, movable cylinder 2, fixed mold 30a, movable mold 30b, half nut 22, tie bar locking device 26, screw engagement adjustment device 40, etc. The fixed mold 30a is attached to a fixed platen 10 fixed on one end of the machine base l, while a movable mold 30b is mounted on the other end of the machine base 1, facing the fixed platen 10. is attached to the movable platen 20. Screws are cut on the outer periphery of the movable cylinder 2 and then inserted into both sides of the connecting plate 50, and one end of the movable cylinder 2 is connected to the cylinder connecting plate 4.
1, and the other end is attached to a movable platen 20 via a piston rod and throat 6, and the machine base 1 can be moved forward and backward by sliding with respect to the fixed platen 10. The movable plate 20
A plurality of tie bars 7 (four in the present invention) are manufactured to have the same diameter throughout the entire length, and one end thereof is fixed to the internal piston 5 of the mold clamping cylinder 3, and the other end is fixed to the connecting plate. 50 and then tightened and fixed with a nut or end plate 51, and at the same time, the tie bar 7 and the connecting plate 50 are prevented from rotating using a key or the like. At approximately the middle part of the tie bar 7, there is a movable mold 30b during the mold closing operation.
At the end of the stroke of the moving cylinder 2, a threaded portion or a groove portion 8 is formed to engage the half nut 22 described above and lock the movable platen 20 to the tie bar 7 before the fixed mold 30a comes into contact with the movable platen 20. ing. The screw engagement adjustment device 40 will be explained using FIG. 2. This screw mesh adjustment device 40 is configured to operate the half nut 22 of the tie bar locking device 26 and the piston head chamber of the half nut opening/closing cylinder 14 in a state where the moving cylinder 20 is at the stroke end before the two full molds come into contact during the mold closing operation. This is used when it is impossible to engage the threaded portion or groove 8 formed on the tie bar 7 by supplying pressure oil to the side 15a. That is, a threaded portion 27 is carved on the outer periphery of the moving cylinder 2, and a drive nut 18 of the A adjustment device 40 is engaged with this threaded portion 27, and a part of the connecting plate 50 is carved. One end of the L-shaped drive nut 18 is brought into contact with the drive nut 18, and the drive nut 18 is made to be rotatable by pressing and contacting the drive nut 18 with a Nantes presser l7.
The other end of the drive nut 18 is located on the side opposite to the connecting plate 50, and the outer circumference of the drive nut 18 has a sprocket portion l9.
The drive nut 18 is prevented from turning by using a key 28 or the like to prevent it from turning, and a presser plate 29 is attached to the side surface to prevent the sprocket part 19 from falling off. The sprocket portion l9 is connected by a chain (not shown), and a sprocket integrated with the output shaft of a motor (not shown) is connected to the chain, and the chain is driven by the rotation of the motor to move the drive nut 18 in the axial direction of the tie bar 7. By moving the movable cylinder 2 back and forth, the movable cylinder 2 and the movable cylinder 2, which are disposed to penetrate through the tie bar 7 in a substantially perpendicular direction, are moved back and forth. Further, a pusher 52 is installed in the insertion hole between the connecting plate 50 and the movable sill 2. Next, using FIGS. 3 and 4, tie bar locking device 2
6 will be explained. The tie bar locking device 26 is connected to the half nut opening/closing cylinder 14,
Piston 15, piston rod 23, half nut 22,
It is constructed from a connecting rod 101 and stoppers 102 and 103. The half nut 22 is provided adjacent to the movable @ 20, and has one set of half nuts 22 each divided into two upper and lower parts for each tie bar 7. One end of the piston rod 23 is fixed. Further, a piston l5 is disposed at the other end of the piston rod 23 and engages with the half-nut opening/closing cylinder 14 to slide up and down, and an adjustment plate lOO is fixed to the lower end of the half-nut opening/closing cylinder l4. 'F: Split nut} 22& and 22b are connected to each other through connections 14'l01 arranged on the left and right sides of the piston rod 23, and one end of the connection 41tl01 is connected to the adjustment plate 1 described above.
00, and the other end is fixed to the half nut 22b. As shown in FIG. 3(a), the piston rod side chamber 15b of the half nut opening/closing cylinder 14
By supplying pressure oil to the nut box 1, the piston 15 is pushed up and the half nut opening/closing cylinder 14 is pushed down, and the upper and lower half nuts 22a and 22b move while sliding on the nut box 2l. Then, the meshing state between the half nut 22 and the tie bar 7 is released, and the respective stoppers 102
, 103, it will stop.
When it is desired to engage the half nut 22 with the tie bar 7, as shown in FIG. 3(b), by supplying pressure oil to the piston head side chamber 15a of the half nut opening/closing cylinder 14, the piston l5 At the same time as pressing down, the half-nut opening/closing cylinder 14 is pushed upward, and the half-nut opening/closing cylinder 14 is pushed upward.
The structure is such that the nut boxes 22a and 22b move while sliding on the nut box 21, and eventually come into contact and engage with the tie bar 7. Next, we will explain the operation of the mold clamping device of the Wooden invention, which is based on 4Ia. In the mold clamping device constructed as described above, the movable platen 20 and the tie bars fixed to the side surface of the movable platen 20 are fixed by supplying pressure oil to the piston head chamber side 4b of the movable cylinder 2 when closing the mold. The stop device 26 moves together with the tie bar 7 in the axial direction towards the fixed platen 10. First, the threaded part or groove part 8 carved in the approximately middle part of the tie bar 7 is connected to the movable platen 20.
As the movable platen 20 is smoothly inserted into the insertion hole 24 of the movable mold 30 and the movable platen 20 moves forward, the movable mold 30b and the fixed mold 30a first come into contact with each other smoothly, and at the end of the stroke of the movable cylinder 2, the movable cylinder 20 moves forward. The supply of pressure oil to the piston head chamber side 4b of No. 2 is stopped. Next, the half nut 22 starts to engage with the threaded part or groove part 8 on the tie bar 7. First, when pressure oil is supplied to the piston head chamber side 15a in the half-nut opening/closing cylinder 14 through a pipe (not shown), the half-nut 22 moves forward in a direction substantially perpendicular to the tie bar 7. Here, in advance, the mold thickness (die bite) H of both molds when the movable mold 30b and the fixed mold 30a are in contact is measured with a scale, and this is measured by the thickness of the thread part or groove part 8 on the tie bar 7. When divided by P (H/P), if it is divisible and there is no fraction below the decimal point, open and close the half nut with the moving cylinder 2 at the stroke end before both full dies come into contact. If pressure oil is supplied to the piston head chamber side 15a of the cylinder l4, the half nut 22 will completely mesh with the threaded portion or groove portion 8 on the tie bar 7. However, contrary to the above, when H/P is not divisible and a fraction below the decimal point occurs, the fraction below the decimal point is divided into 22 screw bitch P)
Because the value multiplied by , completely engages the half nut 22 and the threaded portion 8 on the tie bar 7. The moving distance is A. In other words, by rotating the motor connected by the chain by an amount corresponding to the travel distance glA, the subrocket 1
9 to move the moving cylinder 2 forward and backward. However, the rotation of the motor is measured in pulses and can be converted into the distance traveled by the moving cylinder 2 in its retreat. In this way, it becomes possible to completely engage the half nut 22 with the threaded portion 8 on the tie bar 7. Furthermore, when the engagement is completed, the mold clamping cylinder 3 is ready to start clamping the movable platen mold 30b and the fixed platen mold 30a. Thereafter, strong mold clamping can be started by supplying pressure oil to the piston rod chamber side 5a of the mold clamping cylinder 3 fixedly installed on the fixed platen 10. Injection is performed in this mold clamped state. Furthermore, when opening the mold, the pressure oil in the piston rod chamber side 5a of the mold clamping sill 3 is first released and extracted, and at the same time, when pressure is supplied to the piston head chamber side 5b, the piston 5 moves to the retreating side. The mold opening will then begin. In the present invention, as shown in FIG. 1, it is necessary to carve the threaded part or groove part 8 on the tie bar 7 to be longer than the conventional example shown in FIG. At the end of the stroke of the movable cylinder 2, the mold clamping cylinder 3 enters the mold clamping operation from the state in which the threaded part or groove part 8 of the tie bar 7 and the half nut 22 are engaged. It only needs to be short. Furthermore, a gear may be used instead of the sprocket 19 shown in FIG. In addition, although we have described the case where die high}H is measured using a scale, a scale sensor is installed to automatically detect die high}H, and this data is automatically entered into the computer, and the pre-input tie bar is used. As mentioned above, when H/P cannot be divided by the pitch P of the threaded part on the tie bar 7, the subrocket 19 and the chain should be A necessary pulse may be issued to the motor connected via the H/ When P is split, the half-split nut 22 is set by a computer so that pressure oil is supplied to the threaded portion 8 on the tie bar 7 and the piston head chamber side 15a in the half-nut opening/closing cylinder 14 to cause the half-split nut 22 to engage with the threaded portion 8 on the tie bar 7. This command may be issued, or it may be performed manually. In this embodiment, the movable cylinders 2 are provided on the left and right sides of the connecting plate 50, but the cylinders are not limited to this, and may be provided diagonally or above and below the connecting plate 50. [Effects of the Invention] As described above, according to the present invention, all movement of the movable platen is performed by the moving cylinder regardless of the size of the mold thickness, and only the final mold clamping is performed by the mold clamping cylinder, which is different from the conventional method. The stroke is shorter than that of the device's mold clamping cylinder, and it also requires less hydraulic oil. Also, if the stroke of the mold clamping cylinder is shortened (volume is small), the amount of oil compressed decreases and the time to generate mold clamping force becomes shorter. As a result, the amount of pressurized oil is reduced, so the pressure oil supply device becomes smaller, the manufacturing cost of the mold clamping cylinder becomes cheaper, and the molding cycle of the product becomes shorter. In addition, in conventional equipment, the movable cylinder was fixed to the fixed platen side, so the piston rod of the movable cylinder was always disposed parallel to the tie bars in the periphery of the mold. However, in the present invention, the movable cylinder can be moved from the fixed position of the movable platen. Since it is installed on the panel side, there are no such drawbacks of the conventional method, and the piston rod does not get in the way, improving workability and safety.

[Brief explanation of drawings]

Figures 1 to 4 show one embodiment of the mold clamping device according to the present invention, and Figure 1 shows the screws on the tie bar at the stroke end stage of the movable cylinder before the movable mold and the fixed mold come into contact. Fig. 2 is an enlarged longitudinal sectional view of the screw engagement adjustment device, and Fig. 3 is a tie bar locking seen from line mm in Fig. 1. FIG. 3(a) is a plan cross-sectional view of the device, and FIG. ．． Figure 3(b) shows the case where the split nut and tie bar are disengaged.
shows the operating condition when pressurized oil is supplied to the piston head chamber side of the Y-split nut opening/closing cylinder and the half-split nut and tie bar are engaged. Figure 4 shows an enlarged longitudinal sectional view of the tie bar locking device. Furthermore, FIG. 5 shows a plan longitudinal sectional view showing an example of a conventional device similar to the present invention. l...Machine base, 2...φ...Moving cylinder, 3...Mold clamping cylinder, 4.5...
Piston, 6...Piston rod, 7...
... Tie bar, 8 ... Threaded part or groove, io ... Fixed plate, l4 ... Half nut opening/closing cylinder, 18 ...
...Drive nut, 19...Subrocket part, 20...Movable platen, 21...
・Nut box, 22...Half nut,
26... Tie bar engagement device, 30a... Fixed mold, 30b... Movable mold, 40... Screw engagement adjustment device, 50... Connection plate.

Claims (1)

[Claims] A fixed platen for holding fixed molds having a plurality of mold clamping cylinders was fixed on one end of the machine base, and a movable platen for holding movable molds was opposite to the fixed platen on the other end side of the machine base. The tie bars are mounted so that they can move back and forth in the state, and one end of the plurality of tie bars that pass through the movable platen is attached to a piston part that is slidably provided in each mold clamping cylinder, and the other end is attached to a connecting plate. In a mold clamping device of a molding machine, the movable platen is fixedly installed and has a threaded portion approximately in the center of the tie bar in the axial direction, and a half nut is attached to the movable platen so as to be able to engage with the threaded portion on the tie bar. A mold clamping device for a molding machine, in which a movable platen large stroke moving device for moving back and forth toward a fixed platen is provided between a connecting plate and a movable platen, and a screw engagement adjustment device is provided in the connecting plate and the movable platen large stroke moving device.