JPS6297820A - Composite type mold clamping device - Google Patents

Abstract

PURPOSE:To make both the opening and closing of mold and the mold clamping possible by means of a single driving source by a method wherein a supporting platen is shiftably provided on tie bars provided across a pair of fixed platens so as to connect it with a movable platen by link toggle and at the same time the link toggles are extended and contracted by means of arms. CONSTITUTION:When arms 11 and 11 are pressed by the forward motion of a working member 12, the pressing force is transmitted to a supporting platen 5 as well as to links 10a. Because being resiliently pressed backward by spring members 9, the supporting platen 5 is hard to be shifted and consequently the links 10a rotate inwards about connecting pins, which connect the links 10a with the supporting platen 5 so as to pressingly extend links 10b and consequently to shift a movable platen 3 forward. Furthermore, the supporting platen 5 starts to be shifted together with the link toggles 10, 10 and the movable platen 3 against the spring members 9 so as to close molds 6 and, after that, to further pressurize the molds 6 strongly in order to turn the molds 6 into the clamped state.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a composite mold clamping device for an injection molding machine used for molding synthetic resin.

(Prior art) A complex type mold clamping device called a toggle direct pressure type has a structure in which a movable platen and a ram of a mold clamping cylinder are connected by a link toggle, and the mold is opened and closed by the expansion and contraction of the link toggle. Tightening can be performed by applying pressure to the extended link toggle using a ram.

(Problems to be Solved by the Invention) In general, the above-mentioned composite type mold clamping device can shorten the stroke of the mold clamping cylinder compared to the conventional direct pressure type, and as a result, the mold clamping cylinder can be made smaller. In addition, the mold closing position can be accurately set so that a large mold clamping force is generated at the moment when the link is fully extended. However, in the composite type, the toggle mechanism is only used to open and close the mold, and there is no need to generate mold clamping force, so there is no need to particularly consider the mold closing position, and there is no need to take large amounts of pressure when opening and closing the mold. It has many advantages, including less wear on the connecting pins because no force is applied.

However, since it uses two types, direct pressure and toggle, devices and control means are required to drive the mold clamping cylinder and toggle mechanism, respectively, resulting in higher costs than direct pressure or toggle types. There was a drawback.

(Means for Solving the Problems) This invention was devised to solve the above-mentioned conventional problems, and its purpose is to perform mold opening/closing and mold clamping using one drive source. The object of the present invention is to provide an extremely economical composite type mold clamping device that can perform the following steps.

According to the present invention, the tie bars provided on a pair of fixed plates are movable together with the movable plate, and the tie bars are connected to the movable plate by a link toggle. A member for regulating the retreating position and a spring member such as a receiving plate for always pressing backward are provided, and an arm for extending and retracting the link toggle is provided between the eccentric position of the link toggle and the operating member of the drive device at the rear of the wheat husk. The gist of this is that

(Function) In the above configuration, when the ram is pressurized in the forward direction in the mold open state, the pressure is transmitted to the link toggle via the telescoping arm. Both ends of the link toggle are connected to a receiving plate and a movable plate whose retreating position is regulated, and since the connecting part of the arm is in an eccentric position, the link toggle shortened in the bent state will not operate in the extending direction. , move the movable platen in the mold closing direction.

Even when the link toggle is extended, the ram is still pressurized in the forward direction. Due to the pressure, the receiving plate moves forward together with the link toggle against the spring member, presses the movable plate to close the mold, and then moves on to mold clamping.

When the ram is pressurized in the backward direction in the mold-closed state, the receiving plate is first pulled back to the regulating position by the arm together with the link toggle. The link toggle is then pulled and folded outward from the central joint to shorten it. Due to this shortening, the movable platen is also pulled back and the mold is opened.

This will be explained in detail using an illustrated example.

(Example) In the figure, 1 and 2 are fixed plates, and 3 is a movable plate. Fixed plate 1 above
. The movable platen 3 and the receiving plate 5 are inserted through the tie bar 4.times.4 so as to be able to move forward and backward, and a mold 6 is attached to the movable platen 3 and one fixed platen l.

The receiving plate 5 is provided close to the other stationary plate 2 provided with the drive device 7. Further, both ends of the receiving plate 5 are inserted over the tights s'l- between the regulating members 8, 8 formed by flanges provided on the tie bars 4, 4 at a constant interval, and are always held backward with the spring member 9, i.e. It is being pressed in the direction of the fixed platen 2.

The movable plate 3 and receiving plate 5 are a pair of link toggles 10°10
and each link toggle 10.

10 is connected via parallel arms 11, 11 to an actuating member 12, ie a ram, of the drive device 7 consisting of a hydraulic cylinder.

The arms 11, 11 are connected by pins to a mounting plate 13 provided at the end of the actuating member 12 and to an eccentric position outside the link 10a, so that the actuating member 12 is pressurized in the forward direction. When pressed, the link toggles 10, 10 are pressed, and when pressed in the backward direction, they are pulled back. Note that 14 is a toggle stopper, and 15 is a connecting portion on the movable plate side.

Next, the mold opening/closing and mold clamping operations will be explained.

In the mold open state shown in FIG. 1, the rear chamber 7 of the pressurizing device 7
When pressure oil is supplied to a, the actuating member 12 moves forward and presses the arms 11, 11. The pressing force is transmitted to the links 10a, 10a via the connecting pin at the tip of the arm, and also to the receiving plate 5. Since the support board 5 is pressed backward by the spring member 9, it is difficult to move, so the pressing force acts strongly on the link toggle side, and the link 10a moves inward using the connecting pin with the support board 5 as a fulcrum. Rotate.

Furthermore, since the movable platen 3 connected to the link 101) is in a free state, the rotational force of the link 10a causes the link 1
0b is pushed out and the movable platen 3 moves forward.

The rotation of the link 10a stops when the link 10a contacts the stone/#-14. In addition, at the stop position, as shown in FIG. 2, the arms 11, 11 and link toggles 10, 10 immediately extend, and the movable platen 3 reaches a position where a predetermined gap is left between the molds 6. .

When the link toggles 10, 10 and the arms 11, 11 extend together, the pressing force transmitted to the link 10a acts on the receiving plate 5 through the connecting pin. The receiving plate 5 starts moving forward together with the link toggles 10, 10 and the movable plate 3 against the spring member 9, and as shown in FIG. becomes.

In the mold clamping state, when hydraulic pressure is supplied to the front chamber 7b of the pressurizing device 7 and the movable member 12 is moved backward, the arm 11
, 11, the receiving plate 5 is moved back together with the link toggles 10 and 10 to a position where it comes into contact with the regulating member 8 and stops. As a result, the movable platen 3 also moves backward, and a strong mold opening occurs there.

When the movable member 12 moves further, the link 10a is pulled by the arm 11 and rotates outward. As a result, the link io b bends outward from the central connecting part using the connecting part on the movable platen side as a fulcrum and shortens, and the movable platen 3 also retreats, causing mold opening there, and the first The state shown in the figure will be reached.

Therefore, one pressurizing device 7 can successively perform mold opening or mold closing and mold clamping.

Also, the mold opens and closes at high speed because it uses a toggle.

FIG. 4 shows an example in which a mold thickness adjustment distance adder is provided on the side of the movable platen 3. A rotatable nut member 21 is provided inside the movable platen 3, and a rotatable nut member 21 is provided at the tip of the link toggles 10, 10. A mold thickness adjustment mechanism is provided and the two are screwed together, and by rotating the nut member 21 from the outside manually or by an electric motor, hydraulic motor, etc., the movable platen 3 is moved forward or backward to change the position to match the mold thickness. do.

FIG. 5 shows a case where the tie bar 4 is provided with a mold thickness adjustment device 30, in which a threaded portion 31 is formed at the rear of the tie bar 4 according to the mold thickness adjustment distance, and is screwed into the threaded portion 31 at the rear. , is rotatable relative to the movable fixed platen 2, has a sprocket portion 32 on the outer periphery, has the receiving plate 5 inserted through the front part, and has the regulating members 8, 8 on the front and rear of the receiving plate 5. A cylindrical rotating member 33 having a spring member 9 is provided, each sprocket 32 is connected by a chain 34, and the sprocket 3 integrated with the output shaft of a motor 35 is connected to the chain 34.
6 and drive the chain 34 by the rotation of the motor 35 to rotate the rotating member 33 synchronously.
The position of the rotating member 33 with respect to the tie bar 4 can be changed, and at the same time, the driving device 7 and the receiving plate 5 of the fixed platen 2 connected to the rotating member 33 can be moved relatively on the tie bar 4, and the position of the movable platen 3 can be changed. By changing the position, the mold thickness can be adjusted.

FIG. 6 shows an example in which a drive device that converts rotational motion into linear motion using a serve motor 50, a screw shaft 51, and a nut member 52 is used instead of a hydraulic cylinder.

In this case, a screw shaft 51 is provided between the fixed plate 2 and the receiving plate 5, which is rotated by the drive of a servo motor, and has a nut member 52 in the center that is screwed with the screw shaft 51, and is guided by the tie bar 4 to retreat. An operating panel 53 is provided, to which the arms 11, 11 are connected by means of a pin.

When the servo motor 50 is operated to rotate the screw shaft 51, the operating plate 53 moves back and forth and exhibits the same effect as the ram of the hydraulic cylinder.

In this case, in order to allow the receiving plate 5 to move forward during strong mold clamping, a gap is provided between the tips of the five screw shafts and the receiving plate 5, and a spring 54 is disposed therein.

(Effects of the Invention) As described above, the present invention provides a receiving plate between the movable platen and the drive device, connects the receiving plate and the movable plate by a link toggle, and operates the link toggle and the drive device. An arm was provided across the member, and the arm enabled the link toggle to extend and contract, and a spring member was used to constantly press the receiving plate backwards so that it moved forward and backward only when the link toggle was extended. With the tightening drive device, it is also possible to perform high-speed opening and closing using a link toggle.

Therefore, the toggle drive device and its control device in the conventional toggle direct pressure type can be omitted. In addition, since it is only necessary to interpose a cover between the movable platen and the drive device, it is not particularly complicated compared to conventional systems, and not only can the cost of the device be reduced, but the drive device is also hydraulic. It has the advantage that it can be applied not only to electric vehicles but also to electric vehicles.

[Brief explanation of drawings]

The drawings show a partially longitudinal section of an embodiment of the composite mold clamping device according to the present invention, in which Fig. 1 is a side view when the mold is opened, Fig. 2 is a side view when the mold is closed, and Fig. 3 is a side view when the mold is closed. The figure is a side view when the mold is clamped,
5 and 5 are side views of an embodiment having a mold thickness adjustment device when the mold is closed, and FIG. 6 is a side view of the embodiment equipped with an electric drive device when the mold is opened and closed. 1.2... Fixed plate 3... Movable plate 4... Tights 5... Receiver lid 7...
... Drive device 8 ... Regulation member 9 ...
...Spring member 10...Link toggle 10a, fob...+)7ri 11...
...Arm 12...Operating member patent applicant: 1 person other than Nissei Jushi Kogyo Co., Ltd.

Claims (3)

[Claims] (1) A receiving plate is movably provided together with a movable plate on a tie bar provided on a pair of fixed plates, the receiving plate and the movable plate are connected by a link toggle, and the retreating position of the receiving plate is regulated on the tie bar. and a spring member that always presses the receiving board backward, and an arm for extending and retracting the link toggle is provided between the eccentric position of the link toggle and the operating member of the drive device behind the receiving board. Composite type mold clamping device. (2) The composite mold clamping device according to claim 1, wherein the drive device comprises a hydraulic cylinder and a ram. (3) The drive device includes a screw shaft rotated by an electric motor,
The composite mold clamping device according to claim 1, comprising a plate-shaped movable member that moves forward and backward by the screw shaft using a tie bar as a guide member.