JPH04336217A - Buffer jig for mold equipped with ejector mechanism - Google Patents

Abstract

PURPOSE:To reduce vibration and to suppress noise by impinging a movable mounting plate and a support plate constituting an ejector mechanism against a buffer jig composed of an elastic member at the time of the return operation of the ejector mechanism to a standby position in a mold. CONSTITUTION:A buffer jig is constituted of an elastic member 13, the support ring 14 supported by the elastic member 13 and a bolt 15 piercing the support ring 14 and the through-hole 15c formed to a movable mounting plate 5 to clamp and fix the support ring 14.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorber for a molding die equipped with an ejector mechanism.

0002

[Prior Art] Generally, plastic injection molds are
A fixed mold is supported by a fixed mounting plate arranged at a predetermined position, and a movable mold is supported by the movable mounting plate in correspondence with the fixed mold, and further, the movable mold fixes the movable mold. It is equipped with an ejector mechanism for extruding the resin molded product from the movable mold while being separated from the mold. This ejector mechanism includes an ejector pin that is inserted into and supported by a movable mold, a support plate that supports the pin, a push-back pin that pushes back the ejector pin, and urges the ejector pin, push-back pin, and support plate from the push-out position toward the retracted position. It is comprised of a spring that holds the movable mold and a pressing member that pushes out the support plate together with the ejector pin and the push-back pin against the biasing force of the spring in a state where the movable mold is separated from the fixed mold.

0003

[Problems to be Solved by the Invention] However, in the ejector mechanism described above, when the ejector pin and the support plate are returned to the standby position by the accumulated force of the spring after extruding the resin molded product from the movable mold, the support plate is movable. Since the spring collides with the mounting plate, vibrations and noise are generated, which has a negative impact on the living environment.

SUMMARY OF THE INVENTION An object of the present invention is to provide a shock absorber for a molding die equipped with an ejector mechanism that can eliminate the above-mentioned conventional problems and suppress vibration and noise during operation of the ejector mechanism, thereby eliminating noise pollution. There is a particular thing.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the invention as claimed in claim 1 comprises an elastic member that is removably attached to a movable mounting plate on which a movable mold equipped with an ejector mechanism is attached. There is. Further, the invention as set forth in claim 2 has a configuration in which the elastic member is supported by a support ring supported by a movable mounting plate in claim 1.

[0006]Furthermore, the invention according to claim 3 is based on claim 2.
The support ring is provided with a bolt that passes through an insertion hole formed in the movable mounting plate and tightens and fixes the support ring.

[0007]

[Operation] In the invention according to claims 1 to 3, after the molded product is extruded from the movable mold by the ejector mechanism, when the support plate of the ejector mechanism is returned to the standby position on the side of the movable mounting plate, the support plate is Vibration is suppressed because it collides with an elastic member,
Noise is reduced.

[0008]

[Example] An example embodying this invention is shown below in Figure 1.
This will be explained based on FIG. In the plastic molding die of this embodiment, a fixed die 2 is supported with respect to a fixed mounting plate 1 arranged at a predetermined position as shown in FIG. A movable mold 3 facing the fixed mold 2 is supported by a movable mounting plate 5 via a connecting block 4. Further, the movable mold 3 and the mounting plate 5 are configured to move the resin molded product in the cavity (not shown) in both the molds 2 and 3 to the movable mold while keeping the movable mold 3 separated from the fixed mold 2. It is equipped with an ejector mechanism 6 for extruding from 3.

This ejector mechanism 6 includes an ejector pin 7 inserted into and supported by the movable mold 3, a push-back pin 8 that pushes back the ejector pin 7, and a double support plate 9 that supports the ejector pin 7 and the push-back pin 8. A spring 10 is wound around the push-back pin 8 and biases and holds the ejector pin 7 and support plate 9 from the movable mold 3 to the standby position, and the movable mold 3 is separated from the fixed mold 2. , comes into contact with the support plate 9 through the through hole 5a formed in the movable mounting plate 5,
The push-out rod 11 presses the support plate 9 against the biasing force of the spring 10.

A shock absorber 12 of the present invention is supported on the movable mounting plate 5. This buffer 12 is attached to the movable mounting plate 5
an elastic member 13 made of urethane rubber, foamed urethane resin, soft resin, etc. that is fitted into the mounting recess 5b formed in the mounting recess 5b; a support ring 14 that supports the elastic member 13; and an insertion hole formed in the movable support plate 5. The ring 1 is screwed into the screw hole 14a formed in the center of the support ring 14 from 5c.
4 and a tightening bolt 15 that tightens and fixes the mounting plate 5 to the mounting plate 5. Further, a small-diameter mounting cylinder portion 14b is integrally formed in the center of the support ring 14, and the mounting cylinder portion 14b is connected to a fitting hole 13a formed in the center of the elastic member 13.
It is press-fitted into the Further, an annular groove 14c for preventing slippage is formed on the outer peripheral surface of the mounting cylinder portion 14b, and when the elastic member 13 is press-fitted, a part of the inner peripheral surface of the fitting hole 13a is formed as shown in FIG. The elastic member 13 is elastically deformed and enters the annular groove 14c, thereby preventing the elastic member 13 from separating from the mounting cylinder portion 14b.

Furthermore, the surface of the elastic member 13 is slightly protruded outward from the left side surface of the movable mounting plate 5 to reduce vibrations caused by collision with the right side surface of the support plate 9, and to reduce vibrations caused by collision with the right side surface of the support plate 9. 9 position regulations are implemented. Next, the operation of the molding die configured as described above will be explained. Now, FIG. 2 shows a state before mold release, in which resin is injected into the cavity formed by the fixed mold 2 and the movable mold 3 to produce a resin molded product. In this state, the movable mold 3 is separated from the fixed mold 2 together with the movable mounting plate 5 and the ejector mechanism 6.

In this mold release state, the resin molded product left in the cavity of the movable mold 3 is pushed out by the push rod 11 of the ejector mechanism 6 against the elasticity of the spring 10, so that the ejector pin 7, it is pushed out from inside the cavity. And the extrusion rod 11
moves backward, the support plate 9 is returned to the standby position by the stored force of the spring 10, and the support plate 9 moves toward the shock absorber 12 on the movable mounting plate 5 side. At this time, the elastic member 13 of the shock absorber 12
protrudes slightly from the surface of the mounting plate 5, so the support plate 9
hits the elastic member 13 and does not collide directly with the mounting plate 5, thereby suppressing vibration and noise.

Next, another embodiment of the present invention is shown in FIGS. 3 to 5.
The explanation will be based on. In this embodiment, the stopper itself for regulating the position of the support plate 9 with respect to the movable mounting plate 5 is provided with a function as a shock absorber. As shown in FIG. 5, a support cylindrical portion 14d is integrally formed on the back side of the support ring 14, and the support cylindrical portion 14d is inserted into the insertion hole 5c of the movable mounting plate 5.
The shock absorber 12 is fixed by fitting into the supporting cylinder portion 14d and screwing a bolt 15 into a screw hole 14e formed in the support cylinder portion 14d. In this embodiment, the diameter of the elastic member 13 is, for example, 25 mm.
, its thickness is 5.5 mm, and the diameter of the support ring 14 is 16 mm.
mm, and its thickness is 3 mm. In addition, the mounting cylinder part 14
b has a diameter of 12.8 mm and a thickness of 5.0 mm. The length of the elastic member 13 protruding from the mounting cylinder portion 14b is set to 0.5 mm. Further, the annular groove 14c has a width of 1.5 mm and a depth of 1.0 mm.

Further, in this embodiment, a rod 16 for guiding the movable mold 3 is shown on the fixed mold 2 side. moreover,
As shown in FIG. 4, the buffers 12 are provided at two locations. In this embodiment, the elastic member 13 protrudes from the support ring 14 by, for example, 0.5 mm, so after the protrusion of the elastic member 13 is compressed by the support plate 9, the support plate 9 is supported by the support ring 14. . Moreover, when the movable mold 3 is separated from the fixed mold 2, the compressed length of the elastic member 13 (0.5 m
The elastic force of the spring 10 is set so that the elastic force of the spring 10 moves the ejector pin 7 and the push-back pin 8 together with the support plate 9 in the direction of pushing out the cured molded product from the cavity of the movable mold 3 by the amount of elastic force of the spring 10. As a result, the molded product is slightly lifted out of the cavity, making it easier to extrude the molded product, suppressing the occurrence of cracks in the molded product, and increasing the extrusion speed.

[0015] The present invention is not limited to the above embodiments, but may be embodied as follows. (1) Fitting the elastic member 13 into the fitting recess 5b of the movable mounting plate 5 as shown in FIG. In this case, the elastic member 1
By making the outer diameter of the recess 5b slightly larger than the inner diameter of the recess 5b, the recess 5b is press-fitted and prevented from coming off.

(2) As shown in FIG. 7, the support ring 14 is fitted into the recess 5b of the movable mounting plate 5, and the support ring 9 is made of a magnet to attract the movable mounting plate 5 and prevent it from coming off. To do so. (3) Arbitrarily changing the arrangement position of the shock absorber 12.

[0017]

[Effects of the Invention] As described in detail above, the present invention applies the movable mounting plate and the support plate constituting the ejector mechanism to a shock absorber made of an elastic member when the ejector mechanism returns to the standby position in a molding die. This has the effect of reducing vibration and suppressing noise.

[Brief explanation of drawings]

FIG. 1 is an enlarged cross-sectional view of the main parts of the mounting structure of a shock absorber.

FIG. 2 is a sectional view showing an entire molding die showing an embodiment embodying the present invention.

FIG. 3 is a sectional view of the entire molding apparatus showing another example of the present invention.

FIG. 4 is a sectional view taken along line AA in FIG. 3;

FIG. 5 is an enlarged sectional view showing the mounting structure of the shock absorber used in FIG. 3;

FIG. 6 is a partial cross-sectional view showing another example of the invention.

FIG. 7 is a partial cross-sectional view showing another example of the invention.

[Explanation of symbols]

2 fixed mold, 3 movable mold, 5 movable mounting plate,
5c insertion hole, 6 ejector mechanism, 12 buffer, 13 elastic member, 14 support ring, 15
Tightening bolt.

Claims (3)

[Claims] 1. A shock absorber for a molding die, comprising an ejector mechanism made of an elastic member that is removably attached to a movable mounting plate to which a movable die equipped with the ejector mechanism is attached. 2. A shock absorber for a mold according to claim 1, wherein the elastic member includes an ejector mechanism having a support ring supported by a movable mounting plate. 3. The shock absorber for a molding die according to claim 2, wherein the support ring is provided with an ejector mechanism having a bolt that passes through an insertion hole formed in the movable mounting plate and tightens and fixes the support ring.