JPH02265713A - Clamping apparatus of molding machine - Google Patents

Abstract

PURPOSE:To enable combination to be performed in meshing prior to completion of mold clamping even in the case of combination through screw meshing by providing communicatingly a mold thickness controlling unit in which a stopper shaft in contact with the tip of tie-bars is inwardly mounted movably in an axial direction, in the outside of a combination device. CONSTITUTION:After setting completion of a meshing position on the basis of the thickness of a die, a mold open and close cylinder unit 21 is operated for molding, and clamping is carried out in advancing a movable disc 3. The speed of the mold clamping is slowed down at a predetermined position, and after tie-bars 18 advances into tie-bars insertion hole 14, the tip surface of the tie-bars 18 come into contact with a stopper 15. Since the tie-bars 18 move together with a movable disc 3, a combination device 7 and a clamping piston 6 integrally provided communicatingly to a casing 14 also move to the molding completion position together with the tie-bars 18. After that, even a cylinder 10 is operated, screw shafts 19 and half nuts 9 are securely meshed with each other and combined then integrally.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present 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] A mold clamping cylinder device having tie bar insertion holes is installed in the four corner surfaces of a fixed platen placed on a base, and a movable platen placed on the base is movable with respect to the fixed platen. Tie bars with threaded shafts at the tips are provided at the four inner corners, and a half-nut coupling device is provided on the outside of the stationary plate to connect with the mold clamping piston of the mold clamping cylinder, and the tie bars are clamped by the movement of the movable plate. A mold clamping device that connects a tie bar and a mold clamping piston with a half nut after being inserted into a cylinder, and clamps a mold attached to a fixed platen and a movable platen was disclosed in Japanese Patent Laid-Open No. 63
It is publicly known from the publication No.-317243.

[Problems to be Solved by the Invention] In such a mold clamping device, since connection is performed by thread engagement, the engagement is determined in advance for each mold based on the thickness so that both thread pitches match. determining the location.

For this reason, the connection by meshing cannot be performed until after both molds are completely closed, and as a result, the time until mold clamping pressure is increased becomes longer, which tends to cause a loss in the molding cycle.

This invention is based on the mold clamping pressure increase R1! This was devised in order to solve the rWi problem of 1, and its purpose is to create a new molding machine that can perform the connection by engagement before the mold is closed, even when the connection is done by engagement of screws. Our objective is to provide a mold clamping device.

[! ! Means for Solving the Problem] The present invention according to the above object includes six fixed plates provided on a base, a movable plate provided on the base so as to be able to move forward and backward with respect to the fixed plate, and a fixed plate or a movable plate. a plurality of mold clamping cylinder devices each having a tie bar insertion hole provided therein, a movable platen or a fixed plate having a tie bar having a threaded shaft at its tip in a corresponding portion of the mold clamping cylinder, and a mold for the mold clamping cylinder. In a mold clamping device consisting of a half-nut coupling device connected to a clamping piston and provided on the outside of a fixed platen or a movable platen, and a mold opening/closing cylinder device for moving the above-mentioned plate forward and backward with respect to the fixed platen, the above-mentioned coupling The conventional problems are solved by installing a mold thickness adjustment vRW1, which has a stopper movable in the axial direction and is movable in the axial direction, installed on the outside of the device.

[Function] In the above configuration, when the tip of the tie bar passes through the mold clamping piston and contacts the stopper, the tie bar, the coupling device, and the mold clamping piston become one body in the axial direction, and they move together with the tie bar. The half nut and the screw shaft are engaged with each other during low-speed movement before the mold closing is completed, and the pressure of the mold clamping cylinder device can be increased immediately.

Therefore, it is possible to move to the mold clamping step more quickly than in the case where the two are engaged after the mold opening is completed and then the pressure is increased.

[Example] In the figure, reference numeral 1 indicates six fixed plates provided on one side of the base 2, and reference numeral 3 indicates a movable plate provided on the base 2 so as to be movable with respect to the fixed plate 1.

A mold clamping cylinder assembly [5] having a tie bar insertion hole 4 is installed in each of the four corner surfaces of the fixed platen 1. This tie bar insertion hole 4 is formed with a through hole for a mold clamping piston 6 which is open at both ends, and a coupling device 7 is connected to the outer end of the mold clamping piston 6.

This coupling device 7 is provided with a pair of half nuts 9.9 having threads on the inner surface and facing each other so as to be freely movable in the radial direction in a cover 8 fixed to the outer end surface of the mold clamping piston 6 and having openings on both sides. 9.9 is an attachment to the piston rod 11 of the cylinder 10 provided on the cover 8.

Reference numeral 12 denotes a mold thickness adjustment device, which includes a cylindrical casing 14 with a closed outer end and a screw 13 on the inner surface, a nut-shaped stopper 15 located inside the casing and screwed into the screw 13, and the stopper. It consists of a spline shaft 16 pushed through the center of the casing 15, and a servo motor 17 at the outer end of the casing that rotates the spline shaft 16.

This mold thickness adjustment device! 12 is integrally connected to the coupling device 7 by fixing its open inner end to the outer end surface of the cover of the coupling device 7, whereby the mold thickness adjusting device 12 is movable together with the coupling device 7 by the mold clamping piston 6. That's what I do.

A tie bar 18 is horizontally attached to the inner surface of the movable platen 3 corresponding to the tie bar insertion holes 4 at the four corners. Each end of the tie bar 18.18 is formed into a threaded shaft 19 that engages with the thread of the half nut 9, and the threaded shaft 19
An insertion hole 20 for the spline shaft 16 is bored in the center.

Reference numeral 21 denotes a mold opening/closing cylinder device, in which a cylinder 22 is fixed to the upper part of the fixed platen 1 and a piston 23 is fixed to the upper part of the movable platen 3.

Reference numeral 24 denotes a bottle for preventing the mold clamping piston 6 from rotating, and a protrusion 25 on the side of the cover of the coupling device 7 from the mold clamping cylinder device 5
It is inserted through. Moreover, a limit switch 26 for confirming the most retracted position of the mold clamping cylinder 6 is installed inside the protrusion 25.
It is 1.

Further, 27 is a fixed mold, 28 is a movable mold, 29 is a guide cylinder for the tie bar 18 provided on the fixed plate side, and 30 is a tie bar guide provided in the opening of the mold clamping piston 6.

Next, the operation will be explained.

From the mold open state shown in FIG. 1, the movable platen 3 is moved forward relative to the fixed 111 by the operation of the opening/closing cylinder device 21.
Perform mold closing. As the movable platen 3 moves forward, the tie bar 18 enters the tie bar insertion hole 4 of the mold clamping cylinder device @5, and the screw shaft 19 at the tip becomes the mold thickness adjustment device! ! Fits in 12 casings.

When the mold is completely closed, when the spline shaft 16 is rotated by the operation of the servo motor 17, the casing 1 is
A stopper 15 placed close to the closed end side of the screw lid moves toward the tie bar side and comes into contact with the tip end surface of the screw shaft 19.

Next, the operation of the servo motor 17 is stopped, and the stopper 15
remains in contact position. Then, using this position as a mold closing reference for both molds 27 and 28 attached to the fixed platen 1 and the movable platen 3, the engagement position of the half nut 9 and the screw shaft 19 by the stopper 15 is set.

This setting is performed by moving the stopper 15 forward by the servo motor 17 so that the mold remains closed by the high-pressure mold line or high-pressure mold surface. Furthermore, if the engagement is impaired due to minute screw displacement at the set position, the mold clamping piston 6 is moved to make the adjustment, and the adjusted position is used as the starting point for the mold clamping piston 6 to operate.

In this way, after the setting of the engagement position based on the mold thickness of the mold is completed, the mold opening/closing cylinder device 2 is opened for molding.
1 to move the movable platen 3 forward and close the mold. The mold opening speed is slowed down at a predetermined position, and as shown in FIG. 2, after the tie bar 18 enters the tie bar insertion hole 14, the tie bar 18
The distal end surface of the stopper 18 hits the stopper 18.

Even after hitting this stopper 15, the tie bar 1
Since 8 moves together with the movable platen 3, a coupling device 17 is integrally connected to the casing 14 with the same center line.
The mold clamping piston 6 also moves together with the tie bar 18 to the mold closing completion position.

In addition, since the contact position between the tie bar tip surface and the stopper 15 is set in advance as the engagement position, the position remains unchanged even after contact, and even if the cylinder 10 is operated thereafter, as shown in FIG. 3. As such, the screw shaft 19 and the half nut 9 are reliably engaged and coupled together.

When this connection is detected by a limit switch or the like and pressurized oil is supplied to the mold clamping cylinder device 5, the pressure of the mold clamping cylinder device @5 increases and the process shifts to high-pressure mold clamping.

As a result, when the mold opening shown in FIG. 4 is completed, the mold clamping process has already started, and it becomes possible to inject the molten resin into the mold.

Next, in order to open the mold, the mold clamping cylinder device 5 is first subjected to pressure treatment. As a result, the half nut 9 due to mold clamping pressure
Since the pressure on the mutually meshing surfaces of the screw shaft 19 and the screw shaft 19 is removed, the cylinder 10 is operated to release the meshing by the half nut 9.

Even in this disengagement, the tie bar 18 is connected to the stopper 15.
When the hydraulic pressure supply to the mold clamping cylinder device 5 is switched and the mold clamping piston 6 is moved back to its original position by high pressure, the tie bar 18 is pushed back through the stopper 15, and the high pressure mold An opening occurs.

Note that although the above embodiment uses a screw and a spline as means for moving the stopper 15, the drive device may be a hydraulic motor, and a transmission means such as a chain may also be used in order to synchronize the positions of each location. You can also do it.

Furthermore, in the above embodiment, the mold clamping cylinder device is provided on the fixed platen side and the tie bar is provided on the movable platen side, but the same effect can be achieved even if the mold clamping cylinder device is provided on the movable platen side and the tie bar is provided on the fixed platen side. The present invention is not particularly limited to the above-mentioned embodiments, since the desired effects can be obtained.

[Effects of the Invention] As described above, the present invention includes a mold clamping piston of a mold clamping cylinder device having a tie bar insertion hole provided inside a fixed plate or a movable plate at a required location, a coupling device with a half nut inside, and a tie bar. A stopper in contact with the tip is connected to a mold thickness adjustment device that is movable in the axial direction, and by contact between the stopper and the tie bar tip surface, the half nut and the tie bar tip are adjusted at a position that suits the mold thickness of the mold. Since the meshing position with the screw shaft can be adjusted, 1. The tie bar and mold clamping cylinder can be connected via a half nut at low mold closing speed, and the high pressure process can be started at the same time as mold closing is completed. I can do it.

Therefore, the mold clamping time is shorter than in the past, making it possible to shorten the molding cycle.

[Brief explanation of drawings]

The drawings show one embodiment of the mold clamping device for a molding machine according to the present invention, in which FIG. 1 is a longitudinal sectional view of the main part when the mold is opened, FIG. 2 is a longitudinal sectional view of the main part when the mold is closed, and FIG. Figure 3 is a vertical cross-sectional view of the main parts when combined.
FIG. 4 is a vertical sectional view of the main part during mold clamping. 4...Tie bar insertion hole 5...Mold clamping cylinder device 6...Mold clamping piston 8...Cover 12...Mold thickness adjustment device 1 14...Casing 1 16...Spline shaft 1 18...Tie bar 1 20...Insertion hole 21...Mold opening/closing cylinder device 7 ...Coupling device 9 ...Half nut 3 ...Screw 5 ...Stopper 7 ...Servo motor 9 ...Screw shaft

Claims (1)

[Claims] A fixed platen placed on the base, a movable platen provided on the base so as to be able to move forward and backward with respect to the fixed platen, and a plurality of mold clamping cylinders each having tie bar insertion holes installed inside the fixed platen or the movable platen at required locations. A device, a movable platen or a fixed platen having a tie bar having a threaded shaft at the tip on a corresponding part of the mold clamping cylinder, and a mold clamping piston of the mold clamping cylinder connected to the mold clamping cylinder and provided on the outside of the fixed platen or movable platen. In a mold clamping device consisting of a coupling device for half nuts, and a mold opening/closing cylinder device that moves the movable platen forward and backward relative to the fixed platen, a stopper in contact with the tip of the tie bar is provided on the outside of the coupling device and is movable in the axial direction. A mold clamping device for a molding machine, characterized in that a mold thickness adjustment device built into the molding machine is connected to the mold thickness adjusting device.