JP7350316B2 - Manufacturing method for insert molded products - Google Patents

Description

The present invention relates to a method of manufacturing an insert molded product by integrally molding a resin member on the surface of a metal member.

Patent Document 1 discloses a wiper blade that constitutes a wiper for a vehicle. This wiper blade includes a blade body integrally molded from a resin material and a flat plate member formed from a metal plate and embedded inside the blade body. A holder member is fixed to the flat plate member via a rivet. The holder portion projects outward from the opening of the blade body.

In such a wiper blade, a blade body is integrally molded on the surface of the flat plate member by inserting a flat plate member to which a holder portion is fixed into a mold and filling a cavity with resin. At this time, since the holder part is supported in contact with the mold, it is not covered with resin.

Japanese Patent Application Publication No. 9-39743

By the way, since the holder part is a metal part and is exposed to the outside, it is likely to corrode by reacting with oxygen or chlorine contained in the air or rainwater. As a result, problems arise in that the appearance of the metal parts is impaired and that the resin members are deteriorated by alkaline substances generated when the metal parts corrode.

To address these problems, it is conceivable to perform surface treatment on metal parts for rust prevention prior to molding of resin parts. However, in this case, another problem arises in that the surface treatment layer deteriorates due to the heat generated during molding of the resin part.

Furthermore, it is conceivable to use a material with high rust prevention properties as the metal member. However, in this case, another problem arises in that it is difficult to ensure the strength of the metal member.
Note that such problems are not limited to wiper blades, but similarly occur in insert molded products in which a resin member is integrally molded on the surface of a metal member.

An object of the present invention is to provide a method for manufacturing an insert molded product that can easily manufacture an insert molded product that can suppress corrosion of metal members.

A method for manufacturing an insert molded product to achieve the above object includes supporting a metal member inserted into a mold by a support member at a position away from the molding surface of the mold, and filling a resin into a cavity. By filling, the resin member is integrally molded on the surface of the metal member to produce an insert molded product. The method includes a first step of filling the resin into the cavity with the metal member directly supported by the support member, and during filling the resin into the cavity in the first step, The method includes a second step of separating the support member from the metal member and filling a gap formed between the support member and the metal member with resin.

According to this method, the cavity is filled with resin while the metal member is directly supported by the support member. As a result, the other parts of the surface of the metal member except for the part in contact with the support member are covered with the resin. Furthermore, while the cavity is being filled with resin, the support member is separated from the metal member. As a result, the gap formed between the support member and the metal member is filled with resin.

In the insert molded product formed in this manner, the metal member is not exposed to the outside, so that corrosion of the metal member can be suppressed. Therefore, there is no need to perform surface treatment on the metal member to suppress corrosion prior to molding the resin member. Furthermore, it is possible to select a material that is susceptible to corrosion as the material for the metal member, and it is possible to select a material that has low resistance to alkaline substances as the resin member.

Further, a method for manufacturing an insert molded product to achieve the above object includes supporting a metal member inserted into a mold at a position away from a molding surface of the mold, and filling a resin into a cavity. In this way, a resin member is integrally molded on the surface of the metal member to produce an insert molded product. In this method, a receiving portion is provided at a position of the metal member that protrudes from the resin member, the resin member is molded while supporting the receiving portion, and the receiving portion is removed after the resin member is molded. A rust preventive agent is provided on the end face of the metal member.

According to this method, the resin member is molded by filling the cavity with resin while the receiving portion of the metal member is supported. Thereafter, the receiving portion of the metal member is removed. Then, a rust preventive agent is provided on the end face of the metal member.

In the insert molded product formed in this manner, corrosion of the end face of the metal member can be suppressed. Therefore, there is no need to perform surface treatment on the metal member to suppress corrosion prior to molding the resin member. Furthermore, it is possible to select a material that is susceptible to corrosion as the material for the metal member, and it is possible to select a material that has low resistance to alkaline substances as the resin member.

Further, a method for manufacturing an insert molded product to achieve the above object includes supporting a metal member inserted into a mold at a position away from a molding surface of the mold, and filling a resin into a cavity. In this way, a resin member is integrally molded on the surface of the metal member to produce an insert molded product. In this method, prior to molding the resin member, a resin receiving member is attached to the metal member, and the resin member is molded while supporting the receiving member.

According to this method, a resin receiving member is attached to a metal member prior to molding the resin member. Thereafter, the cavity is filled with resin while the receiving member is supported. As a result, a portion of the surface of the metal member excluding the portion in contact with the receiving member is covered with the resin, and a portion of the receiving member other than the portion in contact with the mold is covered with the resin. Note that the supported portion of the surface of the receiving member is exposed to the outside.

In the insert molded product formed in this manner, the metal member is not exposed to the outside, so that corrosion of the metal member can be suppressed. Therefore, there is no need to perform surface treatment on the metal member to suppress corrosion prior to molding the resin member. Furthermore, it is possible to select a material that is susceptible to corrosion as the material for the metal member, and it is possible to select a material that has low resistance to alkaline substances as the resin member.

According to the present invention, it is possible to easily manufacture an insert molded product that can suppress corrosion of metal members.

FIG. 1 is a perspective view showing an insert molded product manufactured by the manufacturing method of the first embodiment. FIG. 2 is a sectional view taken along line 2-2 in FIG. 1. FIG. 3 is a cross-sectional view showing a state in which the cavity is filled with resin in the first step. FIG. 3 is a cross-sectional view showing a state in which a gap formed between a support member and a metal member is filled with resin in a second step. FIG. 7 is a perspective view showing an insert molded product manufactured by the manufacturing method of the second embodiment. The perspective view which shows the metal component with a receiving part. A perspective view showing an intermediate manufactured product. FIG. 7 is a perspective view showing an insert molded product manufactured by the manufacturing method of the third embodiment. The perspective view which shows the metal component with a receiving member. FIG. 3 is a sectional view showing a state in which the cavity of the same embodiment is filled with resin.

<First embodiment>
Hereinafter, a first embodiment of a method for manufacturing an insert molded product will be described with reference to FIGS. 1 to 4.

As shown in FIGS. 1 and 2, the insert molded product 30 has a long plate shape and an L-shaped cross section.
As shown in FIG. 2, the insert molded product 30 includes a metal member 31 and a resin member 32 integrally molded on the surface of the metal member 31.

The metal member 31 of this embodiment has a long plate shape and an L-shaped cross section. The metal member 31 is made of steel and is embedded over substantially the entire longitudinal direction of the insert molded product 30 .

The metal member 31 is provided with a hole 31a that penetrates in the thickness direction. Although not shown in the drawings, in this embodiment, two holes 31a are provided at intervals in the longitudinal direction of the metal member 31.

The resin member 32 is made of thermoplastic resin and covers the entire surface of the metal member 31.
As shown in FIGS. 1 and 2, a recess 32a is formed on the surface of the resin member 32 at a position corresponding to the hole 31a. The recessed portions 32a are formed on both sides of the resin member 32 (see FIG. 2).

Next, the mold 10 for manufacturing the insert molded product 30 will be explained.
As shown in FIGS. 3 and 4, the mold 10 includes a first mold 11 and a second mold 12 that is movable forward and backward relative to the first mold 11.

A molding surface 13 is formed on the surface of the first mold 11 facing the second mold 12 (the upper surface of FIGS. 3 and 4).
A molding surface 14 is formed on the surface of the second mold 12 facing the first mold 11 (the lower surface of FIGS. 3 and 4).

The first mold 11 is provided with a first support member 21 that has a tip that protrudes from the molding surface 13 toward the second mold 12 and is movable toward the second mold 12. The first support member 21 is provided so as to be slidable with respect to the first mold 11.

The second mold 12 is provided with a second support member 22 that has a tip that protrudes toward the first mold 11 from the molding surface 14 and is movable toward the first mold 11 . The second support member 22 is provided so as to be slidable with respect to the second mold 12.

Both the tip of the first support member 21 and the tip of the second support member 22 are tapered.
Although not shown, two first support members 21 and two second support members 22 are provided, each corresponding to the two holes 31a of the metal member 31.

By clamping the first mold 11 and the second mold 12, a cavity 15, which is a space filled with molten resin (hereinafter referred to as resin R), is formed by the molding surfaces 13, 14 and supporting members 21, 22. be done.

Next, a method for manufacturing the insert molded product 30 using the mold 10 of this embodiment will be described.
First, the first mold 11 and the second mold 12 are clamped with the two holes 31a of the metal member 31 engaged with the tips of the two first support members 21 of the first mold 11 (see FIG. 3). ). As a result, the tips of the two second support members 22 of the second mold 12 engage with the two holes 31a of the metal member 31. By directly supporting the metal member 31 inserted into the mold 10 by the supporting members 21 and 22 at a position away from the molding surfaces 13 and 14 of the mold 10, the metal member 31 is inserted into the mold 10. Positioning is performed.

Subsequently, as shown in FIG. 3, resin R is injected and filled into the cavity 15 while the metal member 31 is directly supported by the supporting members 21 and 22 (first step).
Subsequently, as shown in FIG. 4, while the resin R is being injected and filled into the cavity 15 in the first step, the supporting members 21 and 22 are separated from the metal member 31 and the supporting members 21 and 22 and the metal are separated. The gap formed between the resin R and the member 31 is filled with resin R (second step).

Here, the timing at which the supporting members 21 and 22 are separated from the metal member 31 is such that the resin R is in the cavity 15 to the extent that the metal member 31 is not displaced by the flow pressure of the resin R even if the supporting members 21 and 22 are separated from the metal member 31. The gap is set within a period after the gap is filled and the fluidity of the resin R is ensured to the extent that the gap can be filled with the resin R.

By filling the resin R into the cavity 15 in this way, the insert molded product 30 is manufactured by integrally molding the resin member 32 on the surface of the metal member 31.
Note that the recessed portion 32a on the surface of the resin member 32 is formed by the tips of the supporting members 21 and 22.

Next, the operation of this embodiment will be explained.
By filling the cavity 15 with resin R while the metal member 31 is directly supported by the support members 21 and 22, the parts of the surface of the metal member 31 that are in contact with the support members 21 and 22 are removed. is covered with resin R.

In addition, when the supporting members 21 and 22 are separated from the metal member 31 while the resin R is being filled into the cavity 15, the resin is filled in the gap formed between the supporting members 21 and 22 and the metal member 31. R is now filled.

Next, the effects of this embodiment will be explained.
(1) In the insert molded product 30 molded by the manufacturing method of this embodiment, since the metal member 31 is not exposed to the outside, corrosion of the metal member 31 can be suppressed. Therefore, prior to molding the resin member 32, there is no need to perform surface treatment on the metal member 31 to suppress corrosion. It becomes possible to select a material that is susceptible to corrosion as the material for the metal member 31, and to select a material that has low resistance to alkaline substances as the resin member 32. Therefore, the insert molded product 30 that can suppress corrosion of the metal member 31 can be easily manufactured.

<Second embodiment>
The second embodiment will be described below with reference to FIGS. 5 to 7, focusing on the differences from the first embodiment.

Note that in this embodiment, the same or corresponding configurations as in the first embodiment are given the same reference numerals and redundant explanations will be omitted.
As shown in FIG. 5, the insert molded product 30 includes a metal member 31 and a resin member 32 integrally molded on the surface of the metal member 31. As shown in FIG.

The metal member 31 is not provided with a hole 31a.
The resin member 32 covers the entire surface of the metal member 31 except for both end faces 31c of the metal member 31 in the longitudinal direction. The surface of the resin member 32 has no recessed portion 32a formed therein.

A rust preventive agent 33 is provided on both end faces 31c of the metal member 31.
The mold 10 of this embodiment has the same configuration as the mold 10 of the first embodiment. However, the supporting members 21 and 22 are not provided in the mold 10 of this embodiment.

Next, a method for manufacturing the insert molded product 30 will be explained.
In this embodiment, a metal member 31 shown in FIG. 6 is used. The metal member 31 has a pair of receiving portions 31b extending along the longitudinal direction toward the outside from both longitudinal ends of the main body portion (the portion constituting the insert molded product 30). Each receiving portion 31b has a flat plate shape.

First, the resin R is injected into the cavity 15 while the pair of receiving parts 31b are supported by support parts (not shown) provided in the first mold 11 and the second mold 12 that constitute the mold 10. Fill. As a result, the resin member 32 is molded, and an intermediate product shown in FIG. 7 is formed. The pair of receiving portions 31b are provided at positions of the metal member 31 that protrude from the resin member 32 to the outside.

Subsequently, after molding the resin member 32, each receiving portion 31b is cut off to form each end surface 31c. Then, the insert molded product 30 is manufactured by providing the rust preventive agent 33 on each end surface 31c.

Next, the effects of this embodiment will be explained.
(2) The resin member 32 is molded by filling the cavity 15 with resin R while the receiving portion 31b of the metal member 31 is supported by the supporting members 21 and 22. Thereafter, the receiving portion 31b of the metal member 31 is removed. Then, a rust preventive agent 33 is provided on the end surface 31c of the metal member 31.

In the insert molded product 30 molded by the manufacturing method of this embodiment, corrosion of the end surface 31c of the metal member 31 can be suppressed. Therefore, prior to molding the resin member 32, there is no need to perform surface treatment on the metal member 31 to suppress corrosion. Furthermore, it is possible to select a material that is susceptible to corrosion as the material for the metal member 31, and to select a material that has low resistance to alkaline substances as the resin member 32. Therefore, the insert molded product 30 that can suppress corrosion of the metal member 31 can be easily manufactured.

<Third embodiment>
The third embodiment will be described below, focusing on the differences from the first embodiment, with reference to FIGS. 8 to 10.

Note that in this embodiment, the same or corresponding configurations as in the first embodiment are given the same reference numerals and redundant explanations will be omitted.
As shown in FIGS. 8 to 10, the insert molded product 30 includes a metal member 31, a resin receiving member 34 attached to the metal member 31, and a resin member 32 integrally molded on the surface of the metal member 31. have.

In this embodiment, two receiving members 34 are attached to two holes 31a of metal member 31, respectively.
The receiving member 34 has a shaft portion 34a that is fitted into the hole 31a, and a pair of end portions 34b that are provided at both ends of the shaft portion 34a and have a diameter larger than that of the shaft portion 34a. The end face of the end portion 34b is provided with a recess 34c into which support portions 16 and 17 of a mold 10, which will be described later, can engage. The receiving member 34 may be attached to the hole 31a by thermal caulking, snap-fitting, or molding.

As shown in FIGS. 8 and 10, the resin member 32 covers the entire surface of the metal member 31 except for the portion covered by the end portion 34b of the receiving member 34. As shown in FIGS.
As shown in FIG. 10, the mold 10 of this embodiment has the same configuration as the mold 10 of the first embodiment. However, the supporting members 21 and 22 are not provided in the mold 10 of this embodiment.

The first mold 11 is provided with a first support portion 16 that protrudes from the molding surface 13 toward the second mold 12 .
The second mold 12 is provided with a second support portion 17 that protrudes from the molding surface 14 toward the first mold 11 .

Both the tip of the first support portion 16 and the tip of the second support portion 17 are tapered.
Although not shown, two first support parts 16 and two second support parts 17 are provided, each corresponding to the recesses 34c provided at both ends of the two receiving members 34 attached to the metal member 31. ing.

Next, a method for manufacturing the insert molded product 30 using the mold 10 of this embodiment will be described.
First, prior to molding the resin member 32, two resin receiving members 34 are attached to the two holes 31a of the metal member 31.

Subsequently, the first mold 11 and the second mold 12 are clamped with the recesses 34c of the two receiving members 34 engaged with the tips of the two first support parts 16 of the first mold 11. As a result, the two tips of the two second support parts 17 of the second mold 12 engage with the recesses 34c of the receiving member 34. At this time, the end surfaces of both ends 34b of each receiving member 34 abut on the supporting parts 16, 17 and the molding surfaces 13, 14. By directly supporting the metal member 31 inserted into the mold 10 in this way by the supports 16 and 17 at a position away from the molding surfaces 13 and 14 of the mold 10, the metal member 31 is inserted into the mold 15. Positioning is performed.

Subsequently, as shown in FIG. 10, by injecting and filling the resin R into the cavity 15, the resin member 32 is integrally molded on the surface of the metal member 31, and the insert molded product 30 is manufactured.

In addition, when molding the resin member 32, the end surface of the end portion 34b of the receiving member 34 that was in contact with the supporting portions 16, 17 and the molding surfaces 13, 14 is exposed to the outside (see FIG. 8).

Next, the operation of this embodiment will be explained.
Prior to molding the resin member 32, a resin receiving member 34 is attached to the metal member 31. Thereafter, the cavity 15 is filled with resin R while the receiving member 34 is supported. As a result, the surface of the metal member 31 except for the part that is in contact with the receiving member 34 is covered with the resin R, and the part of the surface of the receiving member 34 that is in contact with the supporting parts 16, 17 and the molding surfaces 13, 14 is covered with the resin R. Resin R covers the rest of the parts except for the part where it is.

Next, the effects of this embodiment will be explained.
(3) In the insert molded product 30 molded by the manufacturing method of this embodiment, since the metal member 31 is not exposed to the outside, corrosion of the metal member 31 can be suppressed. Therefore, prior to molding the resin member 32, there is no need to perform surface treatment on the metal member 31 to suppress corrosion. Furthermore, it is possible to select a material that is susceptible to corrosion as the material for the metal member 31, and to select a material that has low resistance to alkaline substances as the resin member 32. Therefore, the insert molded product 30 that can suppress corrosion of the metal member 31 can be easily manufactured.

<Modified example>
This embodiment can be modified and implemented as follows. This embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.

- In the first embodiment and the third embodiment, the number of holes 31a in the metal member 31 may be three or more. Furthermore, if the metal member 31 can be positioned with respect to the cavity 15, the number of holes 31a can be reduced to one. In this case, it is preferable that the hole 31a has a polygonal shape.

- In the first embodiment and its modifications, instead of the hole 31a penetrating the metal member 31 in the thickness direction, recesses may be formed on both sides of the metal member 31 in the thickness direction. Furthermore, the metal member 31 may be provided with a convex portion that can engage with the supporting members 21 and 22. In short, any shape that can be engaged to be supported by the support members 21 and 22 is sufficient.

- In the first embodiment and its modifications, it is also possible to prevent the depression 32a from being formed on the surface of the resin member 32. In this case, the tip surfaces of the support members 21, 22 are made into planes along the molding surfaces 13, 14 adjacent to the support members 21, 22, and in the second step, the tip surfaces are flush with the molding surfaces 13, 14. The supporting members 21 and 22 may be retracted to the position where .

- In the second embodiment, the number of receiving parts 31b can be one, or can be three or more.
- In the third embodiment and its modifications, instead of the hole 31a penetrating the metal member 31 in the thickness direction, recesses may be formed on both sides of the metal member 31 in the thickness direction. Further, the metal member 31 may be provided with a convex portion for attaching the receiving member. In short, any shape can be used as long as the receiving member can be attached.

- In each of the above embodiments, the shape of the insert molded product 30, that is, the shape of the metal member 31 and the shape of the resin member 32, can be changed to any shape such as a flat plate shape or a cylindrical shape.
- As the metal member 31, metal materials other than steel, such as aluminum and copper, can also be used.

- Thermosetting resin can also be used as the resin member 32.

10... Molding die 11... First die 12... Second die 13... Molding surface 14... Molding surface 15... Cavity 16... First support part 17... Second support part 21... First support member 22... Second support member 30 ...insert molded product 31...metal member 31a...hole,
31b...Receiving part 31c...End face 32...Resin member 32a...Recessed part 33...Rust preventive agent 34...Receiving member 34a...Shaft part 34b...End part 34c...Recessed part

Claims (1)

The metal member inserted into the mold is supported at a position away from the molding surface of the mold, and the cavity is filled with resin, so that the resin member is integrally molded on the surface of the metal member and inserted. In a method of manufacturing a molded article,
Prior to molding the resin member, attaching a resin receiving member to the metal member,
molding the resin member in a state where the receiving member is supported by a molding surface of the mold and the entire metal member is separated from the mold ;
The receiving member includes a shaft portion that is fitted into a hole provided in the metal member, and a shaft portion provided at both ends of the shaft portion, located outside the surface of the metal member, and having a diameter larger than that of the shaft portion. having a pair of ends;
Method of manufacturing insert molded products.