JPS6274618A - Mold clamping of vertical molder - Google Patents

Abstract

PURPOSE:To prevent a worker from being injured and an unloader-inserted from being broken by a method wherein a stopper plate is shifted so as to release the engagement of the stopper plate with a locking rod by the starting action of at least one pushbutton switch and at the same time a mold clamping circuit is closed by means of both the starting signals of two pushbutton switches and the detection signal of a positional detector. CONSTITUTION:A locking rod 9, which is parallel to the direction of movement of a movable platen 1, a stopper plate 19, which checks the forward movement of the movable platen by engaging with the locking rod, and a positional detector to detect the release position of the engagement of the stopper plate are provided on the movable platen 1 so as to shift the stopper plate 19 in order to release the engagement of the stopper plate with the locking rod 9 by the starting action of at least one out of two pushbutton switches 23 and at the same time to perform the mold clamping action by closing a mold clamping circuit by means of both the starting signals of the two pushbutton switches and the detection signal of the positional detector. Because the mechanical safety device is added to the electrical safety device as described above, even if abnormality occurs in electrical circuit, valves and the like, the lowering of the movable platen is interrupted through the engagement of the locking rod with the stopper plate.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a mold clamping method suitable for use in a vertical injection molding machine without a safety cover.

(Prior Art) Vertical injection molding machines are generally widely used for injection molding with inserts, and inserting and ejecting operations are performed manually or by loggets.

Therefore, in many cases, a safety force/J- is not provided for the workability of ejecting/inserting or for moving in and out of the ejecting/inserting machine, so two safety forces are installed on the mold clamping control circuit to prevent accidents for workers. A circuit was used in which a push button switch was used, and the mold would not close unless the operator pressed the push button switch with both hands.

(Problems to be solved by the invention) However, in the conventional method, the mold may be clamped even without a mold clamping operation instruction due to malfunction of the electric circuit or malfunction of the valve, and the hydraulic mold clamping cylinder is not used. If the mold is left open for a long time to replace the mold, the movable plate may fall due to the weight of the clamping ram, movable plate, mold, etc., and leakage of hydraulic oil. In both cases, this was a safety issue for workers.

(Means for Solving the Problems) The present invention has been made in view of the above circumstances, and its purpose is to provide a vertical hydraulic mold clamping device without safety force/J- to an electric circuit. - To provide a new mold clamping method that does not cause the movable platen to fall and cause injury to workers or damage to the ejection/insertion machine even if an abnormality occurs in the mold.

According to the present invention for the above-mentioned purpose, in a vertical mold clamping device that performs a mold clamping operation by closing a mold clamping circuit by activation of two pushbutton switches, a lock rod is provided on a movable platen parallel to the direction of movement thereof, and the lock rod is provided with a movable platen. A stone/flat plate that engages with the movable plate to prevent the movable plate from moving forward, and a position detector that detects the disengaged position of the stopper plate are provided. The operation moves the stopper plate to disengage it from the lock rod, and closes the mold clamping circuit by both the activation signal from the two pushbutton switches and the detection signal from the position detector. The gist of this is to perform the mold clamping operation.

(Function) In the above method, the mold clamping operation is performed by the worker pressing two pushbutton switches (both hands are tied), and by confirming that the lock rod and stopper plate are released in conjunction with the activation of the pushbutton switches. Otherwise, the mold clamping circuit is electrically interrupted by a push button switch, and the movable plate is mechanically locked by the engagement of the lock rod and the stone/flat plate.

The present invention will be specifically explained below using the illustrated apparatus.

(Embodiment) Figures 1 to 3 show a first embodiment, in which a movable platen 1 has a movable mold 2 integrally on its lower surface, and a mold clamping cylinder of a frame 4 on a machine base 3 on its upper surface. The mold is connected to a mold clamping ram 6 inserted into the mold 5, and the mold is opened and closed by raising and lowering the mold clamping ram 6 using hydraulic pressure.

A fixed mold 7 is installed on the machine stand directly below the movable mold.
When the mold is clamped, a molded product cavity is formed by overlapping the movable mold and the fixed mold, and a synthetic resin material is injected by an injection device 8 provided movably back and forth on the side of the parting surface.

On the upper surface of the movable platen 1, a lock rod 9 is provided in parallel with the mold clamping ram 6, and has engagement steps 9' formed in multiple stages. This lock rod 9 is provided concentrically with a through hole 11 formed in a support portion 10 that projects horizontally from the bottom of the mold clamping cylinder.

Further, a lock cylinder 12 operated by hydraulic pressure is provided on the upper surface of the support portion 10, and a stopper plate 14 that acts on the lock rod 9 is attached to the piston rod 13 of the lock cylinder 12.

The stopper plate 14 has a daruma hole 15, and when moving forward, a large diameter portion having approximately the same diameter as the through hole 11 is located above the through hole 11, allowing the lock rod 90 to pass through, and when moving backward, the lock rod 9 The small diameter portion of the daruma hole 15 engages with the small diameter portion of the movable platen 1 to prevent the movable platen l from lowering.

As shown in FIG. 2, on the side of the stopper plate 14, a release confirmation switch 17 and a lock confirmation switch 16, which are proximity switches that detect the forward position (release position) and the backward position of the stopper plate 14, are provided. There is.

The lock cylinder 12 and mold clamping cylinder 5 are connected to a pressure source and an oil tank via directional valves A and B, respectively.

Although the diagram is omitted, the control circuit that operates the switching valve A to the A side to perform the mold clamping operation includes two pushbutton switches that are energized only while being pressed, and the A contact of the release confirmation switch 17, which are connected in series. It is set up so that it will not operate unless the above three signals are input, and when pressed? One of the drawer inches also acts on a circuit that operates the switching valve B in the d direction.

In the mold open state, the lock cylinder 12 is set so as to be retracted so that the lock rod 9 and the locking plate 14 are engaged (as shown in Fig. 3), so that the operator can take out the molded product and insert the next insert. While doing this, move the movable plate 1
is prevented from descending both electrically and mechanically, and the operator completes his preparations and presses the two pushbutton switches with both hands, turning on the two contacts on the control circuit, and at the same time switching valve B 7) Z a direction and the lock cylinder 12
operates in the forward direction, disengaging the lock rod 9 from the stopper plate 14, and turning on the release confirmation switch 17 (
1 and 2), three contacts on the control circuit are closed, switching valve A is switched to side a, and mold clamping operation is performed.

4 and 5 show a second embodiment, in which a through hole is bored on the side of the mold of the movable platen 1 in parallel to the mold opening/closing direction, and a lock rod 9 is inserted therein. Insert it through and fix it with the upper and lower lock nuts (9a, 91).

A hole 18 for inserting the lock rod is provided in the opposite part of the lock rod 9 on the machine side, and a stopper plate 19 for opening and closing the hole 18 is provided in the middle part of the hole 18 and is always pressed in the closing direction by a spring so that it can move forward and backward. It is set in.

The stopper plate 19 is connected to the wire 21 by m springs, and the wire 21 passes through the spring end presser.
It is connected to one end of the crank 22, and the other end of the crank η is in contact with the slope of the inverted triangular pyramid-shaped dog 5 located in the middle of the push button for starting the push button switch. As a result, the stopper plate 9 is always pressed in the closing direction by the spring force, and the wire 21 is also pressed by the spring force.
As the crank n is pulled, the push button 24 is constantly pushed upward.

The relationship between the stopper plate 19 and the push button 24 is as follows:
When the plate 19 closes the insertion hole 18, the push button 24 is in the uppermost position, and when the push button 24 is fully pushed in against the spring, the crank 22 is rotated along the dog 5. , the wire 21 and the stopper plate 19 are pulled to release the insertion hole 18.

It should be noted that confirmation at the time of closing and release is made by a lock confirmation switch 16 and a release confirmation switch 17 installed corresponding to the crank positions at the time of both operations.

Although only one push button switch is shown in the drawing, there is another push button switch on the side of the push button 24. The switch does not operate in conjunction with the stopper plate like the one shown in the figure, but simply turns on and off the current.

Therefore, in the mold open state shown in FIG. 4, while the operator is taking out the molded product and inserting the insert for fire forming, the movable platen 1 is prevented from descending by both electricity and machinery.
When the operator completes preparations and presses the push button and push button switch with both hands, one contact on the control circuit turns ON, and at the same time, the tip of the push button 24 activates the push button switch shown in the figure to turn on the other contact. Crank 22 by dogging
is rotated, and the wire 21 causes the strike iJ? The plate 19 is pulled and retreated, the insertion hole 18 is opened, and the release confirmation switch 17 is activated, so that the third contact on the control circuit is turned ON and the control circuit is closed.

As a result of the above, the directional control valve is activated and the mold clamping operation is performed.

Although the above two embodiments have been described, the present invention can also be used in vertical injection molding machines such as rotary type and sliding type, and the parts that move when the push button switch is activated can be used to
It is more preferable to operate the stylus of the mechanically operated valve provided on the mold clamping hydraulic circuit at the same time so that oil can pass only while the push button is being pressed, as this will also provide hydraulic protection.

Other details such as shape, configuration, quantity, etc. can be changed as desired without departing from the spirit of the invention.

(Effects of the Invention) As described above, the present invention includes a mechanical safety device in addition to the electrical safety device, so even if an abnormality occurs in the electric circuit, valve, etc., the movable platen will not fall. Since this is prevented by the engagement between the lock rod and the stopper plate, it has the feature of significantly improving safety.

[Brief explanation of drawings]

The drawings schematically show a vertical injection molding machine capable of carrying out the method of the present invention, and FIG. 1 is a partially longitudinal side view of the first embodiment when the rod is open, and FIGS. 2 and 3 are views of the stopper. - A partial plan view showing the operating state of the plate; FIG. 4 is a partially longitudinal side view of the second embodiment when the rod is closed; and FIG. 5 is a partially longitudinal side view when the rod is open. l...Movable plate 3...Machine base 5
...Mold clamping cylinder 6 ...Mold clamping ram 9 ... Lock rod 13 , 19 ...
...Stock plate 16...Lock confirmation switch 17...Release confirmation switch 20...Spring 21...Wire n...Crank ...Push button switch 24...Push button 5...
...Dog patent applicant Nissei Jushi Kogyo Co., Ltd. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] In a vertical mold clamping device that performs a mold clamping operation by closing a mold clamping circuit by activation of two pushbutton switches, a movable platen has a lock rod parallel to its moving direction, and a movable platen that engages with the lock rod. a stopper plate that prevents the forward movement of the stopper plate, and a position detector that detects the engagement and release position of the stopper plate, and when at least one of the two push button switches is activated, the stopper plate is moved and the stopper plate is moved. The lock rod is also disengaged, and the mold clamping operation is performed by closing the mold clamping circuit based on both activation signals from the two pushbutton switches and detection signals from the position detector. Mold clamping method for vertical molding machine.