JP4181735B2 - Manufacturing method of resin molded products - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a resin molded article having an extended piece that is pressed against a contact object while being elastically deformed.
[0002]
[Prior art]
Conventionally, when a printed wiring board is disposed in parallel to another board surface (for example, another printed wiring board or a housing panel), for example, as described in Japanese Utility Model Publication No. 1-26144. Fixed fixtures were used. The fixture includes a check piece that is inserted into the mounting hole and caught on the back side of the plate material, and an extension piece that presses against the front side of the plate material while being elastically deformed. The plate material is sandwiched from the front and back and fixed to the plate material.
[0003]
[Problems to be solved by the invention]
By the way, when attaching the said conventional fixing tool to a printed wiring board, unintentionally protrusions, such as a lead wire and a solder lump, may exist around an attachment hole. And when the extension piece is pressed against the printed wiring board in such a state that the protruding object is sandwiched between the printed wiring board, the extension piece is inclined with respect to the surface of the printed wiring board. Along with this, there is a problem that the entire fixture is also tilted.
[0004]
[Means for Solving the Problems and Effects of the Invention]
Therefore, in order to solve the above problem, a new fixture 1 as shown in FIG. 1 has been devised.
The fixture 1 includes a support 3, bases 5 provided at both ends of the support 3, extended pieces 7 extending on both sides of the base 5, support pieces 9 protruding from the base 5, and support A check piece 11 extended so as to be folded back from the tip of the piece 9 and a connecting band 13 for connecting the check piece 11 and the base 5 are provided. And the slit 15 is cut from the front-end | tip of the extension piece 7, and the front end side part of the extension piece 7 is divided | segmented into several (2 in FIG. 1) small piece 7a.
[0005]
According to such a fixture 1, as shown in FIG. 2A, when fixed to the plate materials B1 and B2, as shown in FIG. Since it is pressed against the plate material B2 while being elastically deformed according to the irregularities on the surface of B2 (presence or absence of projections), even when the projection P is present on the plate material B2, the entire fixture 1 is compared with the conventional fixture. Becomes difficult to tilt.
[0006]
However, several problems have arisen in manufacturing such a fixture 1.
First, when the convex portion for forming the slit 15 is formed in the mold, there is a problem that the cost for manufacturing the mold increases.
[0007]
Moreover, since the convex part for forming the slit 15 becomes very thin when the width of the slit 15 is very narrow, there is also a problem that it is easily damaged by, for example, pressure applied during injection molding. Of course, if the thickness of the convex portion provided on the mold can be increased, the strength of the convex portion may be improved to some extent. However, when the fixture 1 having a small outer dimension is made, if the width of the slit 15 cut into the extended piece 7 is increased, the width of the plurality of small pieces 7a divided by the slit 15 is reduced. For this reason, there is a possibility of causing another problem such that the pressure contact force of each small piece 7a is weakened.
[0008]
The present invention has been made to solve these problems, and an object of the present invention is to provide a method for producing a resin molded product that can easily narrow the width of a slit cut from the tip of an extended piece. is there.
In order to achieve this object, the invention described in claim 1
An extension piece extending from the base, and a slit is cut from a tip of the extension piece, and at least a tip side portion of the extension piece is divided into a plurality of small pieces, and the extension piece is In the method of manufacturing a resin molded article configured such that each of the plurality of small pieces is pressed against the contact object while being elastically deformed according to the unevenness of the surface of the contact object when pressed against the contact object. There,
A film material is disposed in the cavity of the mold, a molten resin material having a temperature lower than the melting point of the film material is injected into the cavity, and the film material is removed from the resin molded product after the resin material is solidified. By removing, the slit having a width corresponding to the thickness of the film material is formed.
[0009]
The invention described in claim 2
A check piece that passes through the mounting hole while being elastically deformed when inserted into a mounting hole formed in the plate material, and expands on the back side of the plate material and cannot be pulled out from the mounting hole; An extension piece that presses against the front side of the plate material when the piece is inserted into the mounting hole, and sandwiching the plate material between the check piece and the extension piece, to the plate material When the slit is cut from the tip of the extension piece and at least the tip side portion of the extension piece is divided into a plurality of small pieces, and the extension piece is pressed against the plate member Each of the plurality of small pieces is a method of manufacturing a resin molded product configured to be pressed against the plate material while being elastically deformed according to the unevenness of the surface of the plate material,
A film material is disposed in the cavity of the mold, a molten resin material having a temperature lower than the melting point of the film material is injected into the cavity, and the film material is removed from the resin molded product after the resin material is solidified. By removing, the slit having a width corresponding to the thickness of the film material is formed.
[0010]
In the method for producing a resin molded product, the material of the film material is not particularly limited, but a PET film or the like is preferable in consideration of strength and cost. Also, the resin material for molding the resin molded product is not particularly limited, but it is necessary to select a resin material having a melting point lower than that of the film material and perform the molding process at a temperature lower than the melting point of the film material. Conversely, when the resin material is determined based on the performance required for the resin molded product, it is necessary to select a film material made of a material having a melting point higher than that of the resin material.
[0011]
According to such a method for producing a resin molded product, since the slit is formed in the extended piece by the film material arranged in the cavity of the mold, a thin convex portion is provided in the cavity of the mold. There is no need, and the cost for manufacturing the mold can be reduced to the extent that the cavity has a simple shape.
[0012]
Further, since there are no thin convex portions in the mold cavity, the mold is hardly damaged.
Furthermore, as for the film material, it is possible to adopt a film material that does not easily cost compared to the mold, so that it is not necessary to repeatedly use it so as to cause breakage, and a new film material can be used for each molding. . Therefore, the film material does not need to be selected as much as durability as the mold, and it is easy to adopt a thin film material, and a narrower slit is easily formed when forming a slit in the extended piece. can do.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described with an example.
In the following description, a method for manufacturing the above-described fixture 1 will be described. Since the structure of the fixture 1 has already been described, the description thereof is omitted here.
[0014]
FIG. 3 is a view showing a molding state of the fixture 1 in the mold.
The fixture 1 is made of 66 nylon (melting point: 255 ° C.), and in the mold 21, four fixtures 1 are connected via a runner 23 formed in the molten resin injection path. ing.
[0015]
The mold 21 is a two-plate mold for horizontal injection molding. In FIG. 3, only the fixed side mold is shown. In the fixed side mold, a cavity having a shape in which the unevenness of the half surface of the fixture 1 is inverted is formed only in a portion corresponding to the fixture 1, and the half of the fixture 1 is formed in the movable side mold (not shown). In addition to a cavity having a shape in which the unevenness of the minute portion is inverted, a cavity for molten resin injection corresponding to the runner 23 is formed.
[0016]
The film material 25 is made of PET (melting point: 260 ° C.), and its thickness is as thin as 125 μm, and its length is long so that it can be continuously processed while winding up sequentially. Yes. The film material 25 is provided with a forming hole 27 and a positioning hole 29 according to the forming position of the fixture 1. The molding hole 27 has a shape such that only the portion that becomes the slit 15 overlaps the cavity for molding the fixture 1. The positioning hole 29 is a hole into which a positioning projection (not shown) provided on the mold 21 is fitted when the film material 25 is sandwiched between the fixed side and the movable side of the mold 21.
[0017]
Next, a procedure for forming the fixture 1 will be described.
First, the film material 25 is sandwiched between the fixed side and the movable side of the mold 21 set in the injection molding machine. At this time, a positioning protrusion (not shown) protruding from the mold 21 is fitted into the positioning hole 29, thereby preventing the film material 25 from being displaced relative to the mold 21.
[0018]
Subsequently, a molten resin having a temperature of 255 ° C. is injected from the nozzle and injected from the gate of the mold 21 into the cavity, and the fixture 1 is molded. After molding, the mold 21 is opened, the molded product including the fixture 1 is pushed up from the cavity, the film material 25 is wound up and sent in the longitudinal direction, and the molded product is detached from between the molds 21. .
[0019]
Thereafter, the fixture 1 is continuously formed by repeating this process.
The fixture 1 thus formed is removed from the film material 25. At this time, since the film material 25 is in the extended piece 7 of the fixture 1, when the film material 25 is removed, the extended piece 7 corresponds to the thickness of the film material 25. A slit 15 having a width is formed.
[0020]
When the fixture 1 is manufactured by the above-described manufacturing method, the slit 15 is formed in the extended piece 7 by the film material 25 arranged in the cavity of the mold 21, so There is no need to provide a thin convex portion, and the cost required for manufacturing the mold 21 can be reduced by the amount that the cavity has a simple shape.
[0021]
Moreover, since there is no thin convex part in the cavity of the metal mold | die 21, damage to the metal mold | die 21 is hard to be caused.
Furthermore, the film material 25 is less expensive than the mold 21, so it is not necessary to repeatedly use the film material 25 so as to cause damage, and a new film material 25 may be used every time it is molded. Therefore, the film material 25 does not need to be made of a material that places more importance on durability than the mold 21, and it is possible to employ the thin film material 25 as described above, and in forming the slit 15 in the extended piece 7, A narrow slit 15 can be easily formed.
[0022]
As mentioned above, although embodiment of this invention was described, this invention is not limited to said specific one Embodiment, In addition, it can implement with a various form.
For example, in the said embodiment, although the specific material name was mentioned regarding the material of the fixing tool 1 and the material of the film material 25, what is necessary is just to select arbitrarily regarding each material. However, since it is difficult for the film material 25 to melt when the resin material for molding the fixture 1 is poured in a molten state, the film material 25 is more than the resin material for molding the fixture 1. As a material having a high melting point, it is necessary to inject a molten resin at a temperature lower than the melting point.
[0023]
Moreover, in the said embodiment, although the fixing tool 1 for fixing two board | plate materials to a parallel positional relationship was shown as a resin molded product, of course, you may shape | mold other resin molded products. . Specifically, if one of the structures provided at both ends of the fixture 1 is a resin molded product that can be attached to a plate material, another structure may be adopted for the other. For example, as another structure, if a structure that surrounds and holds the wire bundle from the outer periphery by an annular portion is provided, a clamp that holds the wire bundle wired along the plate material can be configured.
[Brief description of the drawings]
FIG. 1 is a perspective view of a fixture shown as an example of a resin molded product.
FIG. 2A is a view showing a state in which the fixture is attached to a plate material, and FIG. 2B is an end view taken along line AA of FIG.
FIG. 3 is a view showing a molding state of the fixture in the mold.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Fixing tool, 3 ... Support | pillar, 5 ... Base, 7 ... Extension piece, 7a ... Small piece, 9 ... Supporting piece, 11 ... Check piece, 13. ..Connecting band, 15 ... slit, 21 ... mold, 23 ... runner, 25 ... film material, 27 ... molding hole, 29 ... positioning hole.

Claims (3)

An extension piece extending from the base, and a slit is cut from a tip of the extension piece, and at least a tip side portion of the extension piece is divided into a plurality of small pieces, and the extension piece is In the method of manufacturing a resin molded article configured such that each of the plurality of small pieces is pressed against the contact object while being elastically deformed according to the unevenness of the surface of the contact object when pressed against the contact object. There,
A film material is disposed in the cavity of the mold, a molten resin material having a temperature lower than the melting point of the film material is injected into the cavity, and the film material is removed from the resin molded product after the resin material is solidified. A method for producing a resin molded product, wherein the slit having a width corresponding to the thickness of the film material is formed by removing the slit. A check piece that passes through the mounting hole while being elastically deformed when inserted into a mounting hole formed in the plate material, and expands on the back side of the plate material and cannot be pulled out from the mounting hole; An extension piece that presses against the front side of the plate material when the piece is inserted into the mounting hole, and sandwiching the plate material between the check piece and the extension piece, to the plate material When the slit is cut from the tip of the extension piece and at least the tip side portion of the extension piece is divided into a plurality of small pieces, and the extension piece is pressed against the plate member Each of the plurality of small pieces is a method of manufacturing a resin molded product configured to be pressed against the plate material while being elastically deformed according to the unevenness of the surface of the plate material,
A film material is disposed in the cavity of the mold, a molten resin material having a temperature lower than the melting point of the film material is injected into the cavity, and the film material is removed from the resin molded product after the resin material is solidified. A method for producing a resin molded product, wherein the slit having a width corresponding to the thickness of the film material is formed by removing the slit. The film material is a PET film,
The method for producing a resin molded product according to claim 1, wherein the resin material is a resin material having a melting point lower than that of PET.

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