JPH08118368A - Resin mold - Google Patents

Abstract

PURPOSE: To easily take out a molded product from an mold by enhancing the releasability of the molded product. CONSTITUTION: In a resin mold constituted so that the molded product molded between a core mold 1 and a cavity mold 4 is thrust out by an ejector pin 6 to be released from the core mold 1, an ejector piece 8 for molding the wall part 5a of the molded product 5 along with the core mold 1 is provided in the core mold 1 so as to be thrust out of the core mold 1. Further, by thrusting out the ejector piece 8 from the core mold 1 by a slide pin 9 of which the stroke is less than that of the ejector pin 6 at the time of the taking-out of the molded product 5, the wall part 5a is released from the core mold 1 when the ejector piece 8 is thrust out and, therefore, the resistance at the time of the taking-out of the molded product is relaxed to a large extent and the molded product 5 can be easily taken out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin molding die in which a molded product can be easily taken out by improving mold releasability.

[0002]

2. Description of the Related Art In recent years, in order to improve the safety of passengers, an air bag device has been increasingly used in front of a driver's seat or a passenger seat of a vehicle such as a passenger car to reduce the impact at the time of a collision.

In this air bag device, an air bag is compactly housed in a cover which is usually made of resin, and when a shock at the time of collision is sensed, the air bag is instantly inflated and a part of the cover is broken, so that the cover is covered. The airbag protrudes from the inside to absorb the impact, so that the safety of the occupant is ensured.

[Problems to be Solved by the Invention]

The cover used in the conventional airbag device is molded from resin, but has a complicated structure in which a plurality of wall portions (leg portions) are provided on the back surface of the molded product. For this reason, when this cover is molded using a resin mold, there is a problem that when the molded product is released from the mold, it is difficult to take out the molded product due to the resistance of the wall portion and the mold.

Particularly when a molded product is taken out by an automatic take-out machine, the wall of the molded product and the resistance of the molding die cause the molded product to come off the chuck of the automatic take-out machine and the molded product cannot be taken out. There are problems such as remaining and significantly deteriorating the quality of the molded product.

In Japanese Utility Model Laid-Open No. 29520/1990, a resin molding die for molding a molded product having an undercut is proposed. The molding die of the above publication, when the molded product molded between the core mold and the cavity mold is extruded from below using an edger pin, by simultaneously pushing up the undercut molding part from the core mold with a slide pin,
The undercut part of the molded product is designed to be released from the mold. However, the molding die of the above publication has a problem that it can be applied only to molding of a soft resin because the undercut portion is released from the mold by utilizing the elasticity of the molded product.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a resin molding die in which a molded product can be easily taken out by relaxing the resistance at the time of mold release. is there.

[0008]

In order to achieve the above object, the resin molding die according to the present invention is characterized in that a molded product molded between a core mold and a cavity mold is projected by a first projecting member, In a resin molding die in which a molded product is released from a core mold, on a back surface side of the molded product, a second protrusion sandwiched between at least a pair of molded product side walls extending substantially in the molded product projecting direction to the core mold. A member is provided and this second
The protrusion stroke of the protrusion member is smaller than the protrusion stroke of the first protrusion member.

In order to achieve the above object, the resin molding die according to the present invention is the resin molding die according to claim 1, wherein the difference between the protruding strokes of the first and second protruding members is the side wall of the molded product. Between the two, the sandwiching of the second projecting member is set to a range in which a part thereof remains.

In order to achieve the above object, the resin molding die according to the present invention is the resin molding die according to claim 1 or 2, wherein a difference in protrusion stroke between the first and second protrusion members is provided. And an adjusting means for adjusting.

The first projecting member is an edge ectapin that projects a molded product molded between the core mold and the cavity mold and releases the molded product, and the second projecting member is freely projectable to the core mold. It is preferable that it is configured by a straight-up piece that is provided to form the side wall of the molded product, and a slide pin that projects the straight-up piece from the inside of the core die with a smaller stroke than the edge ejector pin when the molded product is taken out.

Further, it is preferable that a stopper whose height is adjustable by a stopper adjusting mechanism is provided in the middle of the slide pin so that the protruding amount of the straight-up piece can be adjusted by the stopper.

Further, the stopper adjusting mechanism has a circular hole-shaped concave portion provided on the outer peripheral surface of the stopper, and an elliptical shaped tip portion fitted into the concave portion, and is rotatable by an appropriate means. It is preferably composed of a stopper pin.

[0014]

When the molded product is projected by the first projecting member and the molded product is released from the core mold, the second projecting member sandwiched between at least a pair of molded product side walls extending substantially in the molded product projecting direction on the core mold. By making a stroke smaller than the protrusion stroke of the first protrusion member, the wall portion of the molded product is released from the core mold, and the wall portion of the molded product is released from the second protrusion member. The resistance can be significantly reduced.

Further, by adjusting the difference between the protruding strokes of the first and second protruding members to the optimum length by the adjusting means, the molded product can be easily taken out even if the length of the wall portion changes. .

[0016]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 is a cross-sectional view of a resin molding die according to the present invention during molding, FIG. 2 is an enlarged view of a second projecting member portion provided in the resin molding die, and FIG. 3 is an adjusting means provided in the resin molding die. FIG. 6 is a side view showing the stopper pin of FIG.

The resin mold according to the present invention comprises a core mold 1 supported on a substrate 2 via legs 3, and a mold mold 4 movable in the contacting and separating directions of the core mold 1. A cavity 1a for molding the wall portion 5a of the molded product 5 is formed in the mold 1, and a cavity 4a for molding the main body of the molded product 5 is formed in the cavity mold 4.

At the center of the core mold 1, there is provided an ejecta pin 6 which is a first projecting member penetrating in the vertical direction, and the upper end of the ejecta pin 6 is almost the same as the upper surface of the core mold 1 when the molded product 5 is molded. In addition to being flush with each other, the lower end of the edge ejector pin 6 is fixed to an edge ejector plate 7 which is vertically movable by a release actuator (not shown).

Further, a recess 1b is formed in a part of the cavity 1a for molding the wall 5a of the core mold 1, and the straight-up piece 8 is vertically slidably accommodated in the recess 1b. A cavity 8a for molding a part of the wall portion 5a is formed between the straight-up piece 8 and the core die 1, and
An upper end of a slide pin 9 provided so as to be vertically slidable is fixed to the lower surface of the straight-up piece 8. Then, the straight-up piece 8 and the slide pin 9 form a second projecting member.

A spring chamber 1c is formed in the lower part of the core mold 1 from which the slide pin 9 projects, and the spring chamber 1c is formed.
A cylindrical stopper 10 and a first compression spring 12 for urging the stopper 10 downward are housed in c, and
The slide pin 9 penetrates through the central portions of the first compression spring 12 and the stopper 10, and a stopper adjusting mechanism 13 is provided in the vicinity of the stopper 10 and constitutes an adjusting means.

The stopper adjusting mechanism 13 adjusts the vertical height of the stopper 10 in accordance with the length of the wall portion 5a of the molded product 5 and the magnitude of the releasing resistance, so that it is perpendicular to the slide pin 9. Stopper pin 14 provided in the core mold 1
It has. As shown in FIG. 4, the tip portion 14a of the stopper pin 14 has an elliptical shape (elliptical shape), the major axis side dimension is a, and the minor axis side dimension is b.
A circular recess 1 formed on the outer peripheral surface of the stopper 10.
It is inserted in 0a.

Further, a tool hole 14b as shown in FIG. 5 is formed on the other end side of the stopper pin 14, and a tool (not shown) such as a hexagon wrench is inserted into the tool hole 14b to make a stopper. By rotating the pin 14, the vertical height of the stopper 10 biased downward by the first compression spring 12 can be freely adjusted.

The lower end of the slide pin 9 is a slide 15 housed in the edge plate 7 so as to be vertically movable.
Is fitted on the upper surface of. The slide 15 is provided in a spring chamber 7a formed in the edge plate 7 so as to be slidable up and down, and in the spring chamber 7a, the first slide is provided.
A second compression spring 16 having a smaller spring force (approximately 1/3) than that of the compression spring 12 is accommodated in the second compression spring 1.
The slide 15 is urged upward by 6.

Next, the operation of the resin molding die configured as described above will be described. In molding the molded product 5, first, as shown in FIG. 1, the mold 4 is brought into close contact with the core 1, and the mold is clamped between the two molds by a mold clamping means (not shown). Resin is injected into the cavities 1a, 4a between the four, but at this time, the ejector plate 7 is at the lower limit position on the base 2, and the straight-up piece 8 is also at the lower limit position, and the upper surface is the upper surface of the core mold 1. It is on the same plane as.

Next, when the molding of the molded product 5 is completed, first the cavity mold 4 is separated from the core mold 1, and in this state, the edge ejector 7 is raised by the mold release actuator as shown in FIG. As a result, the edge ectapine 6 is raised, and at the same time the molded product 5 is ejected from the core mold 1,
Since the slide pin 9 is also pushed up by the slide 15, the straight-up piece 8 is pushed up by the slide pin 9, and the wall portion 5a of the molded product 5 is released from the core die 1.

After that, when the edge plate 7 is further raised, the slide 15 comes into contact with the stopper 10 whose height is adjusted by the stopper adjusting mechanism 13 from below as shown in FIG. Is prevented from rising, and only the edge plate 7 is further increased. As a result, the second compression spring 16 having a smaller spring force than the first compression spring 12 is compressed, and the ejector plate 7 is compressed.
Of the molded article 5a
The wall portion 5a of the mold is released in a range where a part of the wall portion 5a remains on the straight-up piece 8.

As described above, when the straight-up piece 8 is pushed out of the core mold 1, the wall 5a of the molded product 5 and the inside of the core die 1 are separated from each other. The resistance at the time of releasing the mold is greatly reduced, and the molded product 5
Since there is almost no resistance when taking out with an automatic takeout machine,
It can be easily taken out with an automatic take-out machine. In addition, since the length of the wall portion 5a protruding on the back surface of the molded product 5 and the magnitude of the releasing resistance are different, the straight-up piece 8 of the straight-up piece 8 depends on the length of the wall portion 5a and the type of the molding die. It is necessary to adjust the amount of protrusion.

In adjusting the protrusion amount, the height of the stopper 10 may be adjusted by rotating the stopper pin 14 of the stopper adjusting mechanism 13 with a tool.
The height of the stopper 10 can be freely adjusted within the range of the dimension a on the major axis side and the dimension b on the minor axis side of the tip portion 14a of No. 4, and
It is easy to work because it can be adjusted outside the mold.

In the above embodiment, the case where the molded product 5 such as the cover of the airbag device is molded has been described. However, according to the present invention, a protrusion such as the wall 5a is formed on the back surface of the molded product 5. Of course, it can be applied to all molded articles having

[0030]

As described above in detail, in the resin molding die according to the present invention, when the molded product is ejected by the first projecting member and the molded product is released from the core mold, the core mold is substantially molded. Since the second projecting member sandwiched between at least a pair of molded product side walls extending in the product projecting direction strokes smaller than the projecting stroke of the first projecting member,
Since the wall of the molded product is released from the core mold and the wall of the molded product is released from the second projecting member, the resistance at the time of taking out the molded product can be remarkably reduced.

Also, by adjusting the difference between the protruding strokes of the first and second protruding members to the optimum length by the adjusting means, the molded product can be easily taken out even if the length of the wall portion changes. .

Further, a straight-up piece for molding a wall portion or the like protruding on the surface of the molded product is provided in a part of the core die, and when the molded article is pushed out from the core die, this straight-up piece is also After the wall part is released from the core mold by protruding from the core mold, the wall part is released from the core mold by using a two-step release method. Since the resistance is greatly reduced compared to the case of releasing the molded product, the molded product can be taken out easily.

Accordingly, even when the molded product is taken out by the automatic take-out machine, it is possible to solve the problems that the chuck is detached from the molded product and cannot be taken out, or the mark of the chuck remains on the molded product and the quality of the molded product is deteriorated. You can

Further, a stopper whose height can be freely adjusted by a stopper adjusting mechanism is provided in the middle of the slide pin for protruding the straight-up piece, and the protruding amount of the straight-up piece is adjusted by this stopper, so that the wall portion of the molded product or the like can be adjusted. Even if the length or the mold release resistance for each mold is changed, the molded product can be easily and reliably taken out, and the height of the stopper can be adjusted from outside the mold, so that the adjustment work is also easy.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a resin molding die according to an embodiment of the present invention in a resin-filled state.

FIG. 2 is an enlarged view of a second protruding member portion provided on the resin molding die according to the embodiment of the present invention.

FIG. 3 is a side view showing a stopper pin of the stopper adjusting mechanism provided in the resin molding die according to the embodiment of the present invention.

FIG. 4 is a view from the direction A in FIG.

5 is a view from the direction B in FIG.

FIG. 6 is an explanatory view of the operation of the resin mold according to the embodiment of the present invention during the ejection of a molded product.

FIG. 7 is an explanatory view of the operation of the resin mold according to the embodiment of the present invention when the molded product is completely ejected.

[Explanation of symbols]

 1 Core type 4 Cavity type 5 Molded product 5a Wall part 6 Edgerta pin (first push-up member) 8 Straight-up piece (second push-up member) 9 Slide pin (second push-up member) 10 Stopper 10a Recess 13 Stopper adjusting mechanism 14 Stopper pin

Claims (6)

[Claims] 1. A resin molding die in which a molded product molded between a core mold and a cavity mold is released from a core mold by projecting the molded product with a first projecting member, and a back surface side of the molded product. In the core mold, a second projecting member sandwiched between at least a pair of molded product side walls extending substantially in the projecting direction of the molded product is provided, and the projecting stroke of the second projecting member is greater than the projecting stroke of the first projecting member. A resin mold characterized by being made smaller. 2. The resin molding die according to claim 1, wherein the difference between the protrusion strokes of the first and second protrusion members is a range in which the sandwiching of the second protrusion member between the side walls of the molded product partially remains. 3. The resin molding die according to claim 1, further comprising adjusting means for adjusting a difference between protrusion strokes of the first and second protrusion members. 4. The first projecting member is an edge ectapin that projects a molded product molded between a core mold and a cavity mold and releases the molded product, and the second projecting member is freely projectable to the core mold. 3. A straight-up piece provided to form a side wall of a molded article, and a slide pin projecting from the inside of the core die with a stroke smaller than that of the edge ejector pin when the molded article is taken out. Alternatively, the resin molding die according to claim 3. 5. The resin molding die according to claim 4, wherein a stopper whose height is adjustable by a stopper adjusting mechanism is provided in the middle of the slide pin, and the protruding amount of the straight-up piece is adjustable by the stopper. 6. A stopper adjusting mechanism, wherein a circular hole-shaped concave portion provided on the outer peripheral surface of the stopper and an elliptical shaped tip portion are fitted into the concave portion, and are rotatable by an appropriate means. The resin molding die according to claim 5, which comprises a stopper pin.