JPS60192612A - Mold clamper - Google Patents

Abstract

PURPOSE:To clamp molds easily with the push force higher than that of a push device by a method wherein the engaging part of a bar hook with a lock plate, the joint part of the push plate with the bar and the pivot part of the bar with the movable mold are pushed respectively as the fulcrum, the point of force and the point of action. CONSTITUTION:The push force F1 of the push plate 7 given by the hydraulic cylinder 5 uses the bar 12 like a lever with the engaging part of the hook part 12a with the lock plate 14 as the fulcrum A, with the joint part of the bar 12 with the push plate 7 as the point of force B, and with the pivot part of the bar 12 with the movable mold 3 as the point of action to push the movable mold 3 to the fixed mold 2 with the mold clamping force F2. When l1:l2=5:1 is given, F2=F1Xl1/l2=5F1 is obtained, the mold clamping force will be equal to 5 times as large as the push force of the hydraulic cylinder 5. Therefore, the molds will be clamped with the push force higher than the push force of the hydraulic cylinder 5 without changing the push device or the hydraulic cylinder 5.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a mold clamping device for clamping a mold used in injection molding or the like.

<Prior art> Conventionally, a mold clamping device used for this type of molding connects a suppressing means such as a hydraulic cylinder directly to the movable mold side, operates the suppressing means, presses the movable mold against the fixed mold, and closes the mold. If a higher mold clamping force is required, it is necessary to replace it with a suppressor that can generate a higher pressing force.

<Purpose of the Invention> The present invention adds a boosting mechanism with a simple structure to the conventional pressing means, and easily clamps the mold with a pressing force higher than that of the pressing means without replacing the pressing means itself. The purpose is to provide a mold clamping device that can perform this type of mold clamping.

<Structure of the Invention> The gist of the invention is that on the back side of the movable mold, which is provided opposite to the fixed mold, there is provided a pressing plate connected to a pressing means, and an elastic body that urges the pressing plate and the movable mold to be separated from each other. A bar is attached to the suppression plate with a rotating shaft, a hook is formed at the tip of the bar, and the bar is movably connected near the tip of the bar via a slidable pivot. Furthermore, a lock plate that engages with the bar hook is arranged and fixed at a side position of the bar hook when the mold is closed, and when the mold is closed, the bar hook moves in a direction substantially perpendicular to the moving direction of the movable mold and locks. A mold that engages with a plate and presses the movable mold against the fixed mold using the engaging part as a fulcrum, the pivot point between the press plate and the bar as a force point, and the pivot point between the bar and the movable mold as a point of action. It is in the tightening device.

<Embodiment> Fig. 1 is a perspective view of a mold clamping device showing one embodiment of the present invention, Figs. 2a to 2d are schematic front views showing the operating mode of the same embodiment in order, and Fig. 3 is a schematic front view of the same embodiment. It is a schematic front view showing the time of mold clamping.

The mold clamping device of the embodiment is installed in an injection molding machine, and a table 1b with legs (not shown) is provided with a frame l at a position facing each other with tie bars 9, and a fixed mold 2 is mounted on the lower surface of the table 1b. is fixed, and furthermore, four wooden holding rods 4 are protruded downward from the four corners of the table 1b, and the holding rods 4
A holding plate 6 is fixed to the tip, and a hydraulic cylinder 5 is fixedly held on the holding plate 6 with its rod 5a facing upward.

The back side of the movable mold 3 (the first
A suppression plate 7 connected to the rod 5a of the hydraulic cylinder 5 is disposed at the lower side in the figure, and a coil spring is provided between the suppression plate 7 and the movable mold 3 to urge the movable mold 3 upward. An elastic body 8 such as the like is interposed.

Near both sides of the front and rear end surfaces of the suppression plate 7 in FIG. It is attached to the shaft.

Each bar 12 has a pivot portion 13 near its tip that is movable in a direction perpendicular to the moving direction of the movable mold 3 (horizontal direction in FIG. 1) and that restricts movement of the movable mold 3 in the moving direction. It is connected to the movable mold 3 via. Specifically, a sliding hole 3b is formed in a flange portion 3a fixed below the movable mold 3 in a direction perpendicular to the moving direction of the movable mold 3, and a sliding hole 3b is provided protruding from the bar 12 and fitted into the sliding hole 3b. Pin 1 to be inserted
2b, this pivot portion 13 is constructed. Note that, if the bar 12 has sufficient strength, the pivot portion 13 may be constructed by providing a sliding hole in the bar 12 and a pin protruding from the movable flange portion 3a.

A lock plate 14 is arranged and fixed on the table 1b, and is located on the side of the bar hook 12a when the mold is closed and can be engaged with the bar hook 12a.

Note that 16 is an injection cylinder.

Next, the operation mode of the mold clamping device of the embodiment will be explained (see Figures 2a to 2d).

First, when the mold is opened, the movable mold 3 is urged and supported by the elastic body 8 interposed between the movable mold 3 and the suppression plate 7, as shown in FIG. 2a.

When the hydraulic cylinder 5 operates and pushes up the rod 5a, the suppressing plate 7 causes the movable mold 3 to approach the fixed mold 2 through the elastic body 8, and further brings the movable mold 3 into contact with the fixed mold 2. (Figure 2b).

Thereafter, when the rod 5a of the hydraulic cylinder 5 is further pushed up, the suppression plate 7 rises against the biasing force of the elastic body 8. At that time, the bar 1 which is pivoted on the suppression plate 7
2 rotates to narrow the angle with the pressing plate 7, and the vicinity of the tip is connected to the movable mold 3 via the pivot portion 13 so as to be movable only in a direction perpendicular to the direction of movement of the movable mold 3. As a result, the hook portions 12a each move to the side substantially perpendicular to the direction of movement of the movable mold 3, and engage with the lock plate 14 (FIG. 2C).

Then, when the rod 5a of the hydraulic cylinder 5 is actuated to push up the rod 5a, the suppression plate 7 is further pressed upward, but the pressing force is used as a lever to clamp the movable mold 3. (Figure 2d). To explain this action, as shown in FIG. 3, the bar 12 is pivotally attached to the suppression plate 7 by the pin 11, the hook portion 12a is engaged with the lock play) 14, and the vicinity of the tip of the par 12 is attached to the pivot point. 13, the movable mold 3 is connected to the movable mold 3 with its movement in the movement direction regulated, so that the pressing force Fl of the suppression plate 7 by the hydraulic cylinder 5 is less than the hook portion 12a.
The bar 12 is used as a lever, with the engaging part between the bar 12 and the lock plate 14 as a fulcrum A, the pivoting part of the bar 12 and the suppression plate 7 as a point of force B, and the pivoting part of the bar 12 and the movable mold 3 as a point of action C. Then, the movable mold 3 is pressed against the fixed mold 2 with a mold clamping force F2. By the way, 11:! ;L2=5: 1
and sult F 2 = F I X l l / l 2
= 5 F l,! l: Nutte, hydraulic cylinder 5
It is possible to obtain a mold clamping force that is 5 times the pressing force of .

Therefore, mold clamping can be performed with a pressing force higher than that of the hydraulic cylinder 5 without replacing the hydraulic cylinder 5 which is the suppressing means.

Then, after molding the molded product, the rod F' of the hydraulic cylinder 5 is
5. When a is retracted, the mold is opened in a completely opposite manner to the previously described process, and the molded product is taken out.

In the embodiment, a hydraulic cylinder is used as the suppressing means, but other means such as a screw, a rack pinion, etc. may also be used.

Further, in the embodiment, a total of four bars 12 are used, which are connected to the suppression plate 7 and the movable mold 3 and have a lever effect, so as to intersect at the front and rear end surfaces of the suppression plate 7, but the number of bars 12 is If the movable mold 3 is small and a kite mechanism or the like is provided for smooth mold clamping, one movable mold 3 may be sufficient. In addition, as in the example, a plurality of pieces (
If an even number of molds are provided (desirably an even number), the mold clamping force is evenly applied to the left and right sides, so that uniform mold clamping can be performed.

Furthermore, in the embodiment, an elastic body 8 that urges the suppressing plate 7 and the movable mold 3 to be separated from each other is interposed between the pressing plate 7 and the movable mold 3, but this elastic body 8 is provided to enable the bar 12 to perform a lever action when the mold is closed, so the pressure plates 7 to 8 are
The same effect can be obtained even if the bar is provided between the suppression plate and the bar so that the tips of the bar 12 are separated from each other.

<Effects of the Invention> In the mold clamping device according to the present invention, when the mold is closed, the bar, which is pivoted to the suppression plate and movably connected via a pivot near the tip, connects its tip hook to the lock plate. engage,
Using this retaining part as a fulcrum, the pivot point with the pressing plate as a point of force, and the pivot point of the movable mold as a point of action, it acts like a lever to press the movable mold against the fixed mold, thereby pressing the restraining plate. By simply adding a boosting mechanism with a simple structure without replacing the suppressing means, mold clamping can be easily performed with a suppressing force higher than that of the suppressing means.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a mold clamping device showing one embodiment of the present invention, Figs. 2a to 2d are schematic front views sequentially showing the operating mode of the same embodiment, and Fig. 3 shows the mold clamping device of the same embodiment. It is a schematic front view shown. 2... Fixed type, 3... 1■ moving type, 5... (suppressing means) hydraulic cylinder, 7... suppressing plate, 8... elastic body, 12... bar, l 2. a... hook part, 13.
... Pivotal part (3b...sliding hole, 12b...pin),
14...Lock plate, A...Fully point, B...Point of force, C...Point of action. Patent applicant Figure 2q Figure 2b jI Figure 2C! 26ffi

Claims (1)

[Claims] A pressing plate connected to a suppressing means and an elastic body biasing the pressing plate and the movable mold to be separated from each other are disposed on the back side of the movable mold provided opposite to the fixed mold, and the pressing plate has a rotating shaft and is attached to the bar, and a hook portion is formed at the tip of the bar, and near the tip of the bar, it is connected to the movable mold via a slidable pivot, and the bar is connected to the movable mold through a slidable pivot. A lock plate that engages with the bar hook is arranged and fixed at a lateral position of the bar hook when the mold is closed, and when the mold is closed, the bar hook moves in a direction substantially perpendicular to the moving direction of the movable mold. The movable mold is engaged with the lock plate, and the movable mold is engaged with the fixed mold using the engaging portion as a fulcrum, the pivoting portion of the press plate and the bar as a force point, and the pivoting portion of the bar and the movable mold as a point of action. A mold clamping device configured to press against.