JPH0242424Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a die clamper for clamping an injection mold to a die plate in an injection molding machine.

"Prior Art" Conventionally, a die clamper is used to clamp an injection mold to the die plate of an injection molding machine in order to fix it in a replaceable manner. Most types require fluid pressure to be applied to the die plate at all times while it is clamped to the die plate.

Therefore, when the fluid pressure is removed, even temporarily, the force necessary to secure the injection mold to the die plate is immediately removed, and in the worst case, the injection mold is It will fall off the plate.

This can happen, for example, when there is a failure of the hydraulic pump, a failure of the equipment's hydraulic system, a power outage, or other accidents, and in the worst case scenario, the mold may fall off the die plate, resulting in personal injury. It will also lead to.

``Problems to be Solved by the Invention'' The present invention uses a fluid pressure cylinder as described above in the die clamper of a conventional injection molding machine.
When clamping the injection mold to the die plate, in case of hydraulic system failure, power outage or other accident,
In order to prevent the clamping force from immediately disappearing and the injection molding mold falling off the die plate, once the injection molding mold is fixed to the die plate, apply fluid pressure to the fluid pressure cylinder. The clamping force will not loosen even if it is not operated continuously, and the clamping force can be clamped for the first time by actively applying a constant fluid pressure to the fluid pressure cylinder in the direction of loosening the clamping force. so that you can release the
This allows the user to use it with peace of mind.

``Means for Solving Problems'' This invention consists of attaching a holding plate that clamps an injection mold to a die plate to the clamp casing with a mounting pin so that it can swing, and near the tip of this holding plate. The lower end of the first link is pivotably supported on the tip of the cylinder rod of the fluid pressure cylinder, and the root of the second link is also pivoted on the tip of the cylinder rod. The upper end of the second link is slidably attached to the clamp casing along a guide groove cut into the clamp casing, and these cylinder rods, the first link, and the second link constitute a toggle mechanism, and the cylinder rod moves forward. Then, the first link and second link of this toggle mechanism open, and the angle α formed by them is
The clamp casing is provided with a stopper that restricts the forward movement of the cylinder rod at a position of 180 degrees or more.

"Operation" In the initial state when the cylinder rod of the fluid pressure cylinder is retracted, the first link of the toggle mechanism retracts as the cylinder rod retracts, and the first link of the toggle mechanism moves the presser plate pivotally attached to the lower end of the link into contact with the clamp casing. Swing upwards around the mounting pin.

The second link also retreats as the cylinder rod retreats, but its tip slides in the guide groove of the clamp casing.

That is, the first link retreats while swinging the holding plate upward about the mounting pin, so the link becomes inclined with respect to the cylinder rod, and the upper end of the second link falls into the guide groove above the cylinder rod. The angle between the first link and the second link of the toggle mechanism forms an obtuse angle.

Next, in order to clamp the injection mold, fluid pressure is applied to the fluid pressure cylinder to move the cylinder rod forward, and the upper end of the second link moves along the guide groove, and the lower end of the first link moves to the holding plate. While pressing down, move the 1st link and the 2nd link.
Further widen the obtuse angle that can be formed with the link. When the tip of the cylinder rod reaches the stopper position and the angle α formed by both links becomes 180° or more, this is when the strongest clamping force is generated for this toggle mechanism, and the tip of the holding plate holds the injection mold in place. Clamp to the plate.

This clamping force is caused by the angle α between the first and second links of the toggle mechanism as the cylinder rod moves forward.
This occurs when the angle is 180° or more, so if the fluid pressure acting on the fluid pressure cylinder is removed in this state, the angle α between the first link and the second link will be Trying to become bigger through power. As the angle α increases, the cylinder rod tends to move to the right, but this is restricted by the stopper. Even if the fluid pressure acting on the fluid pressure cylinder is removed in this state, the clamping force is not affected at all and the clamping is maintained as it is.

When removing the mold, the clamping force can be easily released by actively applying fluid pressure to the hydraulic cylinder in the opposite direction, thereby retracting the cylinder rod.

"Embodiment" A drawing showing an embodiment of the present invention will be described.

1 is a U-shaped clamp casing,
The holding plate 4 is swingably attached to the casing with attachment pins 5.

The injection molding die 14 is pressed against the die plate 13 by the tip 4' of the holding plate 4 and clamped thereto.

3 is a first link whose lower end is pivotally connected to the pin 6 near the tip of the holding plate 4, and the upper end of the link is connected to the cylinder rod 11 of the fluid pressure cylinder 10.
It is pivotally supported with a pin shaft 7 at the tip thereof so as to be swingable.

Reference numeral 2 designates a second link, the lower end of which is pivotally supported at the tip of the cylinder rod 11 together with the first link 3 by means of a pin shaft 7. The pin shaft 8 at the upper end is attached to the clamp casing 1 so as to be slidable back and forth within a guide groove 9 cut in the clamp casing 1.

The cylinder rod 11 of the fluid pressure cylinder 10, the first link 3, and the second link 2 form a toggle mechanism T.

15 is a stopper for the cylinder rod 11.
Note that the guide groove 9 is provided parallel to the cylinder rod 11.

Now, when fluid pressure is applied to the fluid pressure cylinder 10, the cylinder rod 11 moves in the direction of operating the toggle mechanism T (to the right in FIG. 1).
Along with this, the second link 2 is connected to the cylinder rod 1.
The first link 3 moves along the guide groove 9 while maintaining a shape perpendicular to the first link 3, and the first link 3 presses the inclined presser plate 4 downward around the mounting pin 5, and each link 3, 2 and the presser plate 4 It sequentially moves from the position indicated by the chain line to the position indicated by the solid line.

That is, in the toggle mechanism T, the first link 3
The angle α formed between the second link 2 and the second link 2 becomes wider than the initial obtuse angle, and as a result, the presser plate 4 swings in the direction in which its tip 4' presses the injection mold 14.

When the second link 2 moves along the guide groove 9 and reaches the position of the stopper 15, and the tip of the cylinder rod 11 also reaches the position of the stopper 15, its horizontal movement is stopped. In this position, the angle α between the first link 3 and the second link 2 is 180° or more, and in this state, the first link 3 and the second link 2 push the cylinder rod 11 back toward the fluid pressure cylinder 10. The force is almost zero, and both links 3 and 2
The force that presses the holding plate 4 vertically downward is maximum when the angle α formed by the first link 3 and the second link 2 is 180°, and when the angle α is limited by the stopper 15, It is slightly larger, and even in this state it is almost at its maximum. The toggle mechanism T then mechanically locks the presser plate 4.

Therefore, in this case, the fluid pressure supplied to the fluid pressure cylinder 10 may become zero for some reason, the fluid pressure may leak due to a failure in the fluid pressure piping, or the fluid pressure may be reduced due to some other accident. Even if a situation occurs where the pressure does not activate the toggle mechanism T, link 2,
3. The cylinder rod 11 does not move from the position indicated by the solid line, but always maintains the same position, and clamps the holding plate 4 with a constant force.

When releasing the clamp of the injection mold 14 by the presser plate 4, by operating the fluid pressure cylinder 10 in the opposite direction, the links 2, 3 and the cylinder rod 11 move from the solid line position to the original chain line position. position, the holding plate 4 separates from the injection mold 14 and releases its clamp.

``Effect of the invention'' The invention forms a toggle mechanism with a first link, a second link, and a cylinder rod, and when the angle α between the first link and the second link is 180° or more, The maximum clamping force is generated in the presser plate to which the first link is pivotally connected, and this is used to clamp the injection mold, making it possible to create a strong clamp. Since there is almost no force pushing back in the direction of the pressure cylinder with both links, even if fluid pressure is not supplied to the fluid pressure cylinder or the hydraulic piping of the same cylinder for some reason, the injection molding mold can be maintained by the holding plate. There is no change in the clamp state of the clamp, and the clamp remains strong.

Further, since a toggle mechanism is applied to clamp the injection mold, the fluid pressure cylinder only needs to generate a small force, and therefore a small fluid pressure cylinder can be used.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view of the die clamper of the present invention, FIG. 2 is a sectional view taken along the line A--A in FIG. 1, and FIG. 3 is a perspective view of the entire device. 1... Clamp casing, 2... Second link, 3... First link, 4... Holding plate, 5...
Mounting pin, 9... Guide groove, 10... Fluid pressure cylinder, 11... Cylinder rod, 13... Die plate, 14... Injection mold, T... Toggle mechanism, α... First link 3 and 2 Angle formed by link 2.

Claims (1)

[Scope of utility model registration request] A holding plate 4 is swingably attached to the clamp casing 1 with a mounting pin 5, and the lower end of the first link 3 is swingably supported at the tip of a cylinder rod 11 of a hydraulic cylinder 10 fixed to the clamp casing 1. is pivotally mounted near the tip of the pressing plate 4, and the root of the second link 2 is also pivotally supported at the tip of the cylinder rod 11,
The upper end of the second link 2 is connected to the clamp casing 1
The cylinder rod 11, the first link 3, and the second link 2 constitute a toggle mechanism T, and the cylinder rod 11 moves forward to open the toggle mechanism. The angle α between the first link 3 and the second link 2 of T is
Cylinder rod 11 at a position of 180° or more
A die clamper for an injection molding machine in which a clamp casing 1 is provided with a stopper 15 for regulating the forward movement of the die clamper.