JPH04112012A - Mold clamping device in molding machine - Google Patents

Abstract

PURPOSE:To easily regulate the engagement position at every replacement of a mold and to slow down mold closing velocity by equipping both a sleeve which combines the introduction hole of a tie-bar movably inserted into a mold clamping piston in the axial direction and the acceptance wall of the tip of the sleeve formed in the receiving hole of the mold clamping piston. CONSTITUTION:A sleeve 7 is screwed in the opening of a stationary platen side f a mold clamping cylinder 5 and movably inserted into a mold clamping piston 11 in the axial direction. Since the engagement position of a screw can be regulated by moving a chuck 22 together with the mold clamping piston 11 for a screw shaft 24 by both the sleeve 7 and the receiving wall 7a of the tip of the sleeve formed inside a receiving hole 10 of the mold clamping piston 11, the engagement position in replacement of a mold can be easily set. Further a tie-bar 9 is movablly screwed into a screw cylinder extending to the rear end of the mold clamping piston 11. This tie-bar 9 is linked with the mold clamping piston 11 in the midway part of transfer by both the stopper 16 of the tie-bar and a regulator 12 of mold thickness. Since the slowdown distance can be set, mold clamping is continuously performed to strong mold clamping from highspeed mold clamping.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a mold clamping device used in a molding machine such as an injection molding machine, a die casting machine, or a press molding machine.

[Prior Art] According to Japanese Patent Application Laid-Open No. 63-317243, a movable platen fixes a mold clamping piston of a mold clamping cylinder provided on a fixed platen side and a tie bar with a screw shaft at the tip provided on a movable platen side. A mold clamping device for a large molding machine is known in which, after approaching a plate and closing the mold, a half nut connected to a mold clamping piston and a tie bar screw shaft are engaged with each other to clamp the mold.

[Problems to be Solved by the Invention] This conventional device claims that it is possible to align the phase with the tie bar screw by simply moving the half nut a minute amount in the longitudinal direction as set by the movement adjustment device. The half nut, which is slidably supported via a bracket, is simply pressed against the tip of the ram by a spring, and no specific structure is shown for finely adjusting the meshing position of the nuts.

Furthermore, in this conventional device, when the fixed mold and the movable mold are brought together and the tip of the tie bar passes through the fixed plate and stops, the connection with the half nut is performed by meshing. There are problems such as the inability to slow down the mold closing speed necessary for mold protection using the mold clamping cylinder.

This invention was devised to solve the above-mentioned conventional technical problems, and its purpose is to easily adjust the engagement position each time the mold is replaced, and to make it possible to easily adjust the engagement position each time the mold is replaced. When the mold clamping piston receives the tie bar,
It is an object of the present invention to provide a mold clamping device for a molding machine having a new configuration in which the mold closing speed can be slowed down by a mold clamping cylinder.

[Means for Solving the Problems] The features of the present invention according to the above-mentioned objects include a movable platen that is provided to move forward and backward with respect to a fixed platen installed on a base, and a plurality of movable platens arranged at required locations on the fixed platen. A mold clamping cylinder, a plurality of tie bars whose tips are formed into screw shafts are provided at positions corresponding to the mold clamping cylinders of the movable platen, and a mold opening/closing cylinder that moves the movable platen forward and backward relative to the fixed platen. , a mold clamping piston that is located in the mold clamping cylinder and has a tie bar receiving hole penetrated therethrough, a tie bar stopper that is movably screwed into a threaded cylinder that extends at the rear end of the mold clamping piston, and the stopper. a mold thickness adjustment device consisting of a motor that moves the mold thickness forward and backward;
A pair of tie bar coupling devices are installed on both sides of the mold clamping piston with the chuck that engages with the screw shaft facing the receiving hole, and a screw ring for mesh adjustment is installed in the opening on the fixed plate side of the mold clamping cylinder. Consists of a sleeve that also serves as a tie bar introduction hole, which is screwed onto the outside of the inner end and is fitted so as to be movable in the axial direction into the mold clamping piston, and a receiving wall at the tip of the sleeve formed in the receiving hole of the mold clamping piston. There is a particular thing.

Another feature of the present invention is that the mold thickness adjusting device is screwed into a threaded sash whose outer end is closed and extends to the rear end of the mold clamping piston, and a screw threaded into the inner wall of the threaded sash. Also, a stopper of a tie bar that is fitted with a spline shaft from the outer end of the threaded cylinder and positioned so as to be able to move forward and backward with respect to the receiving hole, a servo motor at the outer end of the threaded cylinder that rotates the spline shaft, and an adjustment bolt for the stopper. It is composed of.

Furthermore, another feature of the present invention is that the mold clamping fringes are provided on the movable platen side and the tie bars are provided on the fixed platen side.

[Operation] In the above configuration, when the sleeve is fed into the interior, the tip of the sleeve hits the receiving wall and moves the mold clamping piston along the screw shaft. As a result, the chuck also moves with respect to the threaded surface of the screw shaft, so that the engagement position of the screw shaft and the chuck can be matched by the sleeve.

Furthermore, when the movable platen moves forward relative to the fixed platen, the screw shaft at the tip of the tie bar enters the mold clamping piston, and the tip end surface hits the stopper in the screw cylinder before mold closing is completed. This allows the tie bar to be stopped by the mold clamping piston via the stopper, and as a result of moving together with the mold clamping piston, the mold closing speed is slowed down. During this slowdown, the screw shaft remains stationary relative to the chuck, so
By the time the mold is completely closed, the tights and the mold clamping piston are connected by meshing.

[In the figure, 1 is a fixed plate installed on one side of the base 2, and 3 is a movable plate installed on the base 2 so as to be movable relative to the fixed plate 1.

Reference numeral 4 denotes a mold opening/closing cylinder, with a cylinder 4a fixed to the fixed platen side and a rod 4b fixed to the movable platen side.

A mold clamping cylinder 5 is integrally provided on the outside of the four corners of the fixed platen 1. In the opening on the fixed plate side of the mold clamping cylinder 4, there is a sleeve 7 which also serves as a tie bar insertion hole with a threaded ring 6 for mesh adjustment screwed onto the outer periphery of the inner end, as shown in FIG. 6 is fixed to the edge of the opening by a hole 8a, and is fitted into the mold clamping cylinder 5 so as to be rotatable and movable.

The mold clamp/ring 5 has a cylinder 8 integrated with the fixed platen 1 and a hole 10 extending in the axial direction for receiving the tie bar 9 on the movable platen together with the sleeve 7. It comprises a mold clamping piston 11 with a receiving wall 7a formed at its tip, a mold thickness adjusting device 12 at the rear end of the mold clamping piston, and a coupling device 13 for the tie bar 9 on the side of the mold clamping piston.

The mold thickness adjusting device 12 includes a screw fl14 whose outer end is closed and extends to the rear end of the mold clamping piston 11, and a threaded cylinder 14 thereof.
A stopper 16 is positioned in the receiving hole 10 so as to be able to move forward and backward by being engaged with a screw formed on the inner wall of the cylinder and a spline shaft 15 extending from the outer end of the threaded cylinder. It consists of a rotating servo motor 17 at the outer end and an adjustment bolt 18 of the stopper 16.

Further, the coupling device 13 includes a cylinder 18 integrally provided on both sides of the mold clamping piston 11, and a piston rod 20.
and a half-nut chuck 22 connected to the tip of the tie bar receiving hole 10 and housed in an annular recess 21 inside the tie bar receiving hole 10 and facing the receiving hole 10, and the cylinder 19 is a cylinder on the mold clamping cylinder side. It moves together with the mold clamping piston 11 through the elongated hole 23 provided in the mold clamping piston 11 .

The tie bars 9 are provided horizontally at the four corners of the movable platen 3 at positions corresponding to the mold clamping cylinders 5. Each tip of each tie bar 9 is formed into a screw shaft 24 that meshes with the screw teeth of the chuck 22.

This threaded shaft 24, the threaded teeth of the chuck 22, and the threads of the threaded cylinder 14 all have the same pitch.

In the figure, 25 is an insertion hole for the spline shaft 15 drilled in the center of the screw shaft 24, 26 is a limit switch for confirming the backward limit of the stopper 16, 27 is a rotary encoder,
28 is a fixed mold, and 29 is a movable mold.

Further, in the above embodiment, the mold clamping cylinder 5 is provided on the fixed platen side and the tie bar 9 is provided on the movable platen side, but if necessary, the mold clamping cylinder 5 is provided on the movable platen side and the tie bar 9 is provided on the fixed platen side. It may be provided.

Next, mold thickness adjustment will be explained with reference to FIGS. 5 to 8. Note that only cross sections of the screws in each part in the drawings are shown. Further, the threads of the threaded cylinder 14 have eight pitches, and other threads are also provided in accordance with these pitches.

In this mold clamping device, the original position of the stopper 16 is set, and the position of the stopper 16 with respect to the tie bar 9 is adjusted based on this original position.

Setting of this original position is carried out by attaching a mold 30 with the minimum mold thickness to the fixed platen 1 and the movable platen 3, as shown in FIG. First, after the mold is closed, a slight deviation in the engagement position between the chuck 22 and the screw shaft 24 is adjusted. This adjustment can be easily performed by rotating the sleeve 7 and feeding it into the interior, and moving the chuck 22 together with the mold clamping piston 11.

Next, the spline shaft 15 is rotated by the motor 17 to send out the stopper 16, so that the stopper 16 comes into contact with the end face of the screw shaft. After the motor 17 has stopped, the bolt 18 is fed out and the stopper 16
This position is set as the original position of the stopper 16, and the proximity switch 2B for confirming the backward limit is set to operate at this position.

The mold thickness adjustment accompanying mold replacement is performed after a new mold 30a is installed, as shown in FIG.

First, the mold is closed and the screw shaft 24 of the tie bar 9 is inserted into the mold clamping piston 11. Thereafter, the stopper 16, which has been lowered to its original position, is moved by the motor 17 and comes into contact with the end face of the screw shaft, as shown in FIG.

Next, in order to set the slowdown distance of the mold clamping speed, the mold 30a is opened by a required dimension L1, as shown in FIG. Due to this mold opening, the tie bar 9 also retreats, and the end face of the screw shaft is separated from the stopper 16 by the same distance L1. This size.

is the slowdown distance.

After adjusting the engagement position using the sleeve 7, the stopper 16 is moved again by the motor 17 to the end face of the screw shaft and comes into contact with it. Due to this contact, the tie bar 9 is stopped by the mold clamping piston 11 via the stopper 16 before the mold is closed, and moves together with the mold clamping piston 11 over a distance until the mold is closed.

In addition, since the engagement position has already been adjusted in the state in which it is in contact with the striker and parr 16, the chuck 22 can be moved forward during the slowdown to engage and connect with the screw shaft 24, and the mold can be closed. Afterwards, you can immediately shift to strong mold clamping.

In the mold clamping device in which the mold thickness is adjusted as described above, when the opening/closing/cylinder 4 is hydraulically operated in the mold open state shown in FIG. I'm going to close it.

As shown in FIG. 3, as the movable platen 3 moves forward, the tie bar 9
The threaded shaft 24 at the tip enters the inside of the mold clamping piston 11 from the sleeve 7, and before the mold is completely closed, it comes into contact with the stopper 16, which has been positioned in advance based on the thickness of the mold,
The clamping piston 11 allows the receiver to be stopped. As a result, the mold clamping piston 11 moves to the mold closing completion position together with the tie bar 9 while discharging the hydraulic oil from the rear oil chamber side, thereby slowing down the mold closing speed.

Further, due to the contact with the stopper 16, the screw shaft 24 of the tie bar 9 faces the pair of chucks 22 of the coupling device 13 in a stationary state, so when the cylinder 19 is hydraulically operated after slowing down, the chuck 22 is pushed out and engages with the side surface of the screw shaft of the tie bar 9.

When this engagement is sensed by a limit switch or the like and completion of mold closing is confirmed, hydraulic oil is supplied to the front oil chamber 31 and high-pressure mold clamping is performed there, as shown in FIG.

When the molding is completed, hydraulic oil is supplied to the rear oil chamber 32,
The hydraulic oil in the front oil chamber 31 is discharged by the mold clamping piston 11, and powerful mold opening is performed there. After the mold is opened forcefully, the mesh is released and the mold is opened by the mold opening/closing cylinder 4.

[Effects of the Invention] As described above, the present invention includes a sleeve 7 which is screwed into the opening on the fixed plate side of the mold clamping cylinder 5 and fitted so as to be movable in the axial direction up to the inside of the mold clamping piston 11; The receiving wall 7a at the tip of the sleeve formed inside the receiving hole 10 of the mold clamping piston 11 allows the chuck 22 to be moved together with the mold clamping piston 11 relative to the threaded shaft 24 to adjust the engagement position of the screw. Because of this, it is easy to set the engagement position when replacing the mold, and even slight deviations can be corrected by slight movement by the sleeve, so damage to the screw due to poor engagement can be prevented.

Furthermore, the tie bar 9 is controlled by a mold thickness adjusting device 12 consisting of a stopper 16 of the tie bar 9 movably screwed into a threaded cylinder extending from the rear end of the mold clamping piston 11 and a motor 17 that moves the stopper 16 forward and backward. is connected to the mold clamping piston 11 during the movement so that the slowdown distance can be set, so that the process from high-speed mold closing to strong mold clamping can be carried out continuously.

Furthermore, an adjustment bolt 18 for the stopper 16 is provided at the outer end of the threaded cylinder 14 of the mold thickness adjustment device 12, so that the original position of the stopper 16 can be set. It has the following advantages: the amount of movement of the stopper 16 can be controlled.

[Brief explanation of drawings]

The drawings show an example of a mold clamping device for a molding machine according to the present invention, and FIG. 1 is a longitudinal side view of the mold clamping cylinder section, and FIG. cross section,
Fig. 3 is a partial sectional view showing the state immediately before mold closing, Fig. 4 is a partial sectional view showing the high-pressure mold clamping state, Fig. 5 is a partial sectional view illustrating setting the stopper in its original position, and Fig. 6 to Fig. FIG. 8 is a partial sectional view illustrating adjustment of the engagement position and stopper position due to mold exchange. 16...Stopper 18...Adjustment bolt 24...Screw shaft

Claims (3)

[Claims] (1) A movable platen that can move forward and backward with respect to a fixed platen that is placed on a base, a plurality of mold clamping cylinders that are arranged at required locations on the fixed platen, and a mold clamping cylinder of the movable platen. A plurality of tie bars are provided at corresponding positions with the tips formed into screw shafts, a mold opening/closing cylinder that moves the movable platen forward and backward relative to the fixed platen, and a tie bar receiving hole in the mold clamping cylinder is provided. A mold thickness adjusting device comprising a mold clamping piston provided therein, a tie bar stopper movably screwed into a threaded cylinder extending at the rear end of the mold clamping piston, and a motor for moving the stopper forward and backward; A pair of tie bar coupling devices are provided on both sides of the mold clamping piston with the chuck that engages with the screw shaft facing the receiving hole, and a screw ring for mesh adjustment is inserted into the opening on the fixed plate side of the mold clamping cylinder. It is characterized by consisting of a sleeve that also serves as a tie bar introduction hole, which is screwed onto the outer end of the mold so that it can move freely in the axial direction into the mold clamping piston, and a receiving wall at the tip of the sleeve formed inside the receiving hole. A mold clamping device for a molding machine. (2) In the mold clamping device for a molding machine according to claim 1, the mold thickness adjusting device includes a threaded cylinder whose outer end is closed and extends to the rear end of the mold clamping piston, and an inner wall of the threaded cylinder. The stopper of the tie bar is fitted with the spline shaft from the outer end of the threaded cylinder and positioned so as to be able to move forward and backward with respect to the receiving hole, and the stopper of the tie bar, which rotates the spline shaft, A mold clamping device for a molding machine, comprising a servo motor and a stopper adjustment bolt. (3) The mold clamping device for a molding machine according to claim 1, wherein the mold clamping cylinder is provided on the movable platen side, and the tie bar is provided on the fixed platen side.