JPH0730342Y2 - Mechanical mold clamping safety device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a mechanical mold clamping safety device that stops a mold clamping operation of a movable mold plate when a safety door of an injection molding machine is opened.

(Prior Art) As a mechanical mold clamping safety device that stops the mold clamping operation of the movable mold plate when the safety door of the injection molding machine is opened, the fourth conventional method has been proposed.
A mechanism as shown in Figures 6 to 6 is used.

4 to 6, 1 is a fixed mold mounting plate, 2 is a movable mold mounting plate, 3 is a mold clamping cylinder or toggle plate, 4
Is a tie bar. Reference numeral 11 is a stopper rod, which is provided with a plurality of grooves 12 for inserting stopper arms. This stopper rod 11 is arranged in parallel with the tie bar 4, and one end thereof is attached to the side surface of the movable attachment plate 2 on the side where the safety door 9 is attached.
A lock nut 14 is attached to the shaft 13 so that the position thereof can be adjusted in the axial direction. The other end of the stopper rod 11 is a stopper block provided on the mold clamping cylinder or toggle plate 3.
It penetrates through the hole 16 of 15 and projects to the surface side of the stopper block 15 that does not face the movable mounting plate, that is, to the left side in FIG. Reference numeral 17 denotes a stopper arm that is engageable with the groove 12 of the stopper rod 11 and is disengaged from the stopper rod 11 by swinging around a pin 18 on the surface of the stopper block 15 that does not face the movable mounting plate. Provide to get. This stopper arm 17 is provided with an operating roller 19 and the operating roller 19
The cam 20 attached to the safety door 9 engages with the safety door 9 closed, and the stopper arm 17 is separated from the stopper rod 11 only in this state. The stopper arm 17 is always engaged with the stopper rod 11 when the safety door 9 is opened by a predetermined amount or more.

When the safety door 9 is closed, the cam 20 pushes the actuating roller 19 in the direction of the arrow shown in FIG. 6, and the stopper arm 17 is separated from the stopper rod 11. The plate 2 can be moved forward. However, when the safety door 9 is opened by a predetermined amount or more, the cam 20 does not engage with the actuating roller 19, so the stopper arm 17 engages with the groove 12 of the stopper rod 11, and the movable mounting plate 2 of the movable type mounting plate 2 is erroneously operated. Block forward. At this time, since a tensile load acts on the stopper rod 11, even if the stopper rod 11 has a relatively small diameter, it can sufficiently withstand a large mold clamping force.

Further, the stopper rod 11 is not located between the movable die and fixed die mounting plates 2 and 1, but is arranged between the movable die mounting plate 2 and the mold clamping cylinder or the toggle plate 3, so that It does not impede various work such as mounting and removing work performed between the two type mounting plates 2 and 1.

If a large number of grooves 12 are provided as shown in FIGS. 4 to 6, by changing the axial mounting position of the stopper rod 11 to the support base 13 only within the range of the mutual intervals of the grooves 12, 12. It can be applied to dies of any thickness, and even if the safety door 9 is opened during the advance of the movable die attachment plate 2, the advance of the die attachment plate 2 can be prevented in the middle thereof.

(Problems to be Solved by the Invention) When the safety door 9 is opened during the mold clamping operation in the conventional device, an electrical limit switch that reacts to the movement of the safety door 9 causes a hydraulic pressure to move the movable mold plate in the "closed" direction. An electrical safety circuit works by turning off the solenoid of the hydraulic valve that supplies oil to the cylinder. Also, independently of this, a dual safety circuit that simultaneously operates the cam type hydraulic switching valve that reacts to the movement of the safety door 9 and cuts off the oil supply to the hydraulic cylinder that is also moved in the "closed" direction. Although equipped in the molding machine, a mechanical mold clamping safety device is installed in case the two become damaged at the same time and become inoperable.
However, in the actual molding site, it seems that this equipment is useful in the following situations.

That is, while the control power is on and the hydraulic pump is rotating, the operator can open the safety door 9 and put a part or all of the body into the mold where the operation is stopped after the mold opening. Is often seen (a caution nameplate is put on the mold so that it enters the mold after the control power is turned off, but it is generally ignored). When the safety circuit of the C. lost its function, the mold suddenly started to be closed, which could endanger the worker.

If equipped with a mechanical clamping safety device, the advance of the mold is blocked by the device during its acceleration phase (ie low speed),
Accidents can be prevented. Apart from this, what is often seen in the field is that during normal closing of the mold, the operator may find something abnormal in the mold and open the safety door to stop the mold closing operation. , In this case, since the mold is moving at high speed, even if the electric and hydraulic safety circuits move correctly, it does not stop immediately and the mechanical mold clamping safety device should absorb this very large kinetic energy. To work.
However, in this state, it is unlikely that an operator puts a part of his / her body in the mold, and therefore the safety device mainly aims to prevent damage to the mold and the like.

In the conventional mechanical mold clamping safety device, at the same time when the safety door 9 is opened,
Since the cam 20 pushing up the stopper arm 17 is disengaged and the stopper arm 17 immediately moves due to gravity, it is necessary to absorb a very large amount of kinetic energy as described above. Therefore, the mechanism must be structured to withstand a large force. I had to do it.

If the safety door 9 is opened during the mold opening process, the stopper arm
17 hits the step of the stopper rod 11 and emits an abnormal noise of about 10 Hz,
Makes the operator uncomfortable. Since this operation is often performed by the operator, it was disliked in the field.

The present invention installs an air- or oil-filled damper on the rotating part of the stopper arm, and the damper works when the stopper arm rotates and falls by its own weight, and it hardly works when the stopper arm is lifted by a cam. It is intended to provide a device.

(Means for Solving the Problems) Therefore, according to the present invention, one end of a round bar is fixed to a supporting base mounted on the side surface of a movable die plate, and the other end of the round bar is a stopper block attached to a cylinder plate. Through the through hole of
One or more recessed grooves are formed in the round bar to form a stopper bar, which is attached to the surface of the same stopper block opposite to the movable mold plate so as to rotate by a pin, and is attached to the groove of the stopper bar by gravity. In a mechanical mold clamping safety device consisting of a stopper arm that falls down and becomes a stopper and is lifted by a cam attached to the safety door, and a mechanical clamping safety device consisting of the stopper rod, a damper is attached to slow down the movement of the stopper arm into the groove of the stopper rod. Which is a means for solving the problems.

(Action) The action of the damper makes the movement of the stopper arm slow. That is, even if the safety door is opened rapidly, the stopper arm slowly falls onto the stopper rod, so that in a normal operating state, the safety device using electric and hydraulic circuits moves faster than the mechanical safety device.

In the unlikely event that both the electrical and hydraulic safety circuits fail, the mechanical safety device will work. Further, even if the door is opened in the process of opening the mold, the operation of the mechanical safety device is slow, so that an unpleasant noise is generated only once or twice.

(Embodiment) The present invention will be described below with reference to the embodiments of the drawings. Figs. 1 to 3 show an embodiment of the present invention. First, FIG. 1 is a perspective view of a mechanical safety device attached to an injection molding machine, FIG. 2 is a front view of the same, and FIG. 3 is a shape of a serrated groove 42 of a stopper rod 41 which is a main part of the safety device. Indicates.

In FIGS. 1 and 2, reference numeral 32 denotes a movable mold plate (platinum) of an injection molding machine, to which an injection mold is attached, and the movable mold plate 32 is guided by a tie bar 34 to be attached to a cylinder plate 33. It is moved in the direction of the arrow by the ram of the attached hydraulic cylinder. 39 is a safety door that moves in the direction of the arrow, and a cam plate 50 is attached to the upper part. Reference numeral 41 is a stopper rod, and as shown in FIG. 3, a plurality of grooves 42 having a sawtooth side cross section are provided. The stopper rod 41 is screwed into a support base 43 attached to the upper side surface of the movable die plate 32, and is fixed with a nut 44. Further, the stopper rod 41 passes through a through hole of a stopper block 45 attached to the upper side surface of the cylinder board 33, and the stopper rod 41 and the tie bar 34 are attached in parallel.

47 is a stopper arm, and a stopper block is provided by a pin 48.
It is attached to 45 and rotates about a pin 48, and a roller 49 is attached to the lower end of the stopper arm 47. The roller 49 can rotate horizontally around a pin (not shown) fixed to the stopper arm 47 as an axis. 51 is a damper, which is pinned to the stopper block 45 by a pin 53, and the rod end of the damper 51 is pinned to the stopper arm 47 by a pin 52.
This damper 51 encloses air or oil, and the stopper arm 47
When the stopper part of is lowered by gravity, it exerts a damping action.

Next, the operation of the embodiment configured as described above will be described. First, in the mold closing step, the movable mold platen 32 moves in the upper right direction of the arrow shown in FIG. At this time, the stopper rod 41 also moves at the same time and passes through the through hole of the stopper block 45. When the safety door 39 is opened during movement of the movable mold plate, the cam plate 50 also moves in the lower left direction in FIG. 1, the roller 49 at the lower end of the stopper arm 47 moves along the cam plate 50, and the stopper portion of the stopper arm 47. Falls by its own weight, but it slowly falls by the action of the damper 51 and enters the groove 42 of the stopper rod 41.

If the movable die plate 32 cannot be stopped due to a failure of the electric or hydraulic circuit, the plane perpendicular to the groove 42 of the stopper rod 41 is the stopper arm.
The movable block 32 is blocked by the stopper 47 and stopped by the stopper block 45.

Next, in the mold opening process, when the movable mold platen 32 is moving in the direction of the arrow mold shown in FIG. 1, when the safety door 39 is opened, the roller 49 at the lower end of the stopper arm 47 moves down the cam and the stopper arm 47 is opened.
The stopper portion 47 slowly descends and hits the inclined portion of the groove 42 of the stopper rod 41. Therefore, the stopper portion of the stopper arm 47 is pushed up due to the inclination, and the stopper rod 41 continues to move as it is. That is, the mechanical stopper does not work during the mold opening process.

(Effects of the Invention) The present invention is configured as described in detail above, and since the operation for stopping the movable mold plate is performed gently, if the safety door is opened during the mold clamping process during normal operation, the electricity The safe operation by the hydraulic circuit and hydraulic circuit always works before the mechanical mold clamping safety device to stop the mold board.The mechanical mold clamping safety device is complementary only when the electric circuit and the hydraulic circuit malfunction. It can fulfill its original purpose of moving reliably. Further, in the mechanical type mold clamping safety device, an excessive force is hardly applied to the stopper arm and the stopper rod in the normal operation, so that the size can be reduced and the cost can be reduced. Furthermore, according to the present invention, unpleasant noise can be reduced and
A good work environment can be provided to the operator.

[Brief description of drawings]

FIG. 1 is a perspective view of a mechanical mold clamping safety device according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line II--FIG. 1, FIG. 3 is a side view of a stopper rod in FIG. FIG. 5 is a plan view of a conventional mechanical mold clamping safety device, FIG. 5 is a sectional view taken along line V--V in FIG. 4, and FIG. 6 is a sectional view taken along line VI--VI in FIG. Description of main parts of the drawing 32 ... Movable platen, 33 ... Cylinder plate 39 ... Safety door, 42 ... Stopper rod groove 43 ... Support base, 45 ... Stopper block 47 ... Stopper arm, 48 ... Pin 50 ... Cam plate, 51 ... damper

Claims (1)

[Scope of utility model registration request] 1. One end of a round bar is fixed to a supporting base mounted on the side surface of a movable mold plate, and the other end of the round bar passes through a through hole of a stopper block mounted on a cylinder plate and is attached to the round bar. One or more concave grooves are formed to form a stopper rod, and it is attached to the surface of the same stopper block opposite to the movable mold plate so that it can be rotated by a pin, and it falls into the groove of the stopper rod by gravity and becomes a stopper. In a mechanical mold clamping safety device comprising a stopper arm lifted by a cam attached to a safety door and the stopper rod, a damper is attached to slow down the movement of the stopper arm into the groove of the stopper rod. A mechanical mold clamping safety device.