JP2001003916A - Fixing fitting - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance a bonding force of a member made of resin and a fixing fitting buried in the member and to enhance a durability of the fixing fitting without generating a stress concentration from an outer periphery of the fixing fitting to the resin of the portion contacted therewith. SOLUTION: The fixing fitting is used by burying it in a member made of resin. A female screw 11 to which a bolt as a shaft member is attached is formed on a fitting body 12 as a shaft hole and a resin biting portion 15 is provided on an outer periphery. Stripe projections 16 projectedly formed on the outer periphery of the resin biting portion 15 and curved portions 18a, 18b circumferentially curved are provided on both axial end sides. A surface of the stripe projections 16 is formed to a circular shape and an engagement groove 19 surrounded by the circular surface is formed between the stripe projections 16 circumferentially adjacent each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing fitting which is embedded in a synthetic resin member and used for mounting a shaft member such as a screw member or a pin.

[0002]

2. Description of the Related Art A notebook personal computer has a personal computer main body and a personal computer display which is attached to the personal computer by a hinge so as to be openable and closable. Each housing is formed of synthetic resin. . The hinge has a metal cylindrical fixing bracket and a shaft member composed of a screw member such as a bolt and a pin attached to the metal, and the fixing bracket includes a casing of the personal computer main body and a casing of the personal computer display section. It is designed to be embedded in one of the body.

[0003] Even in a portable telephone having a cover member that can be opened and closed, the housing of the main body is formed of resin, and the resin housing of the main body is connected to the resin cover via a metal hinge. The members are designed to be freely openable and closable,
The hinge has a metal cylindrical fitting.

[0004]

In the case of using a metal fixing bracket embedded in a resin member such as a housing,
To press-fit the fixing bracket into the fitting hole provided in the resin member at the time of molding, or to insert-mold the fixing bracket when molding the resin member using thermoplastic resin. I have. In insert molding, a fixing member is arranged in a molding die to form a resin member, and the fixing member can be embedded in the resin member at the same time as molding.

As described above, when the fixing bracket is embedded in a resin member, it is necessary to process the outer periphery of the fixing bracket so that the outer periphery of the fixing bracket and the resin are firmly connected to each other.
Conventionally, the outer peripheral surface of the fixing bracket is knurled to form an uneven portion on the outer peripheral surface.
Not only is there a limit to the bonding force between the resin and the fixing bracket, but when external force is applied to the fixing bracket, stress concentrates on the resin portion that contacts the knurled irregularities, which can cause cracks and cracks. Was. In particular, when the tip of the uneven portion on the outer peripheral surface was sharp, cracks and cracks were remarkably generated.

SUMMARY OF THE INVENTION It is an object of the present invention to increase the bonding force between a resin member and a fixing member embedded therein, and to prevent stress concentration from occurring at the portion of the resin contacting from the outer peripheral portion of the fixing member. It is to improve the durability of the fixing bracket.

[0007]

A fixing bracket according to the present invention is a fixing bracket embedded in a resin member. The fixing bracket has a shaft hole in which a shaft member is mounted, and a cylindrical member having a resin biting portion on an outer peripheral portion. A metal body having a shape, and a plurality of streak-like projections formed on the outer peripheral surface of the resin biting portion of the metal fitting body and having both ends in the axial direction curved in the circumferential direction. The surface is formed in an arc shape, and a meshing groove surrounded by the arc-shaped surface of the streak is formed between the streaks adjacent in the circumferential direction.

In the fixing bracket according to the present invention, the metal fitting body is provided with a plurality of resin biting portions separated through an annular groove, and the bending directions at both ends of the streak-like projections are set adjacent to each other in the axial direction. The directions of the resin bite portion and the other resin bite portion may be opposite to each other. In the fixing bracket of the present invention, the shaft hole may be a female screw to which a screw member is screwed.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a front view showing a fixing bracket according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line 2-2 in FIG. 1, and FIG. FIG. 4 is a cross-sectional view taken along a line, and FIG. 4 is a cross-sectional view taken along a line 4-4 in FIG.

The fixing bracket 10 is made of a metal such as brass, aluminum, stainless steel, steel, or the like, and has a cylindrical metal fitting body 12 in which a through hole for a female screw 11 as a shaft hole is formed at the center. A flange portion 13 is formed at one end of the metal fitting body 12, and a resin biting portion 15 is formed at the other end side through an annular groove 14.

On the outer peripheral surface of the resin biting portion 15, a plurality of streaky projections 16 extending along the central axis of the fitting main body 12 project outward of the fitting main body 12, and are formed at predetermined intervals in the circumferential direction. Have been. Each of the stripe-shaped projections 16 has a substantially straight central portion 17 and curved portions 18a and 18b formed on both ends of the central portion 17 so as to be curved in the circumferential direction.

Each of the stripe-shaped projections 16 has a substantially semicircular cross-sectional shape and an arc-shaped surface. The entire line from one end to the other end of each of the stripe-shaped projections 16 including the curved portions 18a and 18b has a semicircular cross-sectional shape. A meshing groove 19 surrounded by the arc-shaped surface of the streak-like projection 16 is formed between them.

The number, width and height of the strip-like projections 16 and the width of the engagement groove 19 can be arbitrarily set according to the outer diameter of the fixture 10 and the dimension in the axial direction.

The fixing fitting 10 can be manufactured by processing a predetermined shape using a metal material and then plastically forming the resin biting portion 15 using a rolling roller or a plate roll.

FIG. 5 is a sectional view showing a state in which the fixing fitting 10 shown in FIGS. 1 to 4 is embedded in a resin member 20. The resin member 20 is made of a thermoplastic resin using a resin molding die. At the time of molding, the fixing fitting 10 is insert-molded by molding in a state where the fixing fitting 10 is arranged in a molding die. In the case shown in FIG. 5, only the portion of the resin biting portion 15 is embedded in the resin member 20, but the fixing fitting 1 including the flange portion 13 is provided.
The entirety of 0 may be embedded in the resin member 20.

At the time of molding, the resin in the molten state enters the engagement groove 19 of the resin biting portion 15, and when the resin is cooled, the resin undergoes cooling shrinkage. Has an arcuate shape and meshing groove 1
9 is surrounded by an arc-shaped surface, so that the surface of the streak-like projections 16, particularly the top surface, is not sharp, so that stress is not dispersed due to cooling shrinkage and the stress is dispersed. Become. Thereby, it is possible to prevent cracks and cracks from occurring in the resin member. Similarly, when the fixing member 10 is used by screwing a screw member such as a bolt to the female screw 11, the fixing member 10 is used.
Even if an external force is applied via the screw member to the
Since no stress concentration occurs at 0, cracking and cracking of the resin can be prevented even during use.

Moreover, since each of the stripe-shaped projections 16 is curved at both ends in the circumferential direction, even if an axial load is applied when the fixing bracket 10 is used, each of the stripe-shaped projections 1 is bent.
6 surely digs into the resin that has entered the engagement groove 19, thereby preventing the fixture 10 from coming off the resin member 20.

FIG. 6 is a front view showing a fixing fitting 10 according to another embodiment of the present invention.
The curved portions 18a and 18b provided at both ends of the curved line 18 are curved in the circumferential direction in the adjacent streaked projections 16 in the opposite direction.
In other words, the curved portions 18a, 18b of each of the stripe-shaped projections 16 are curved.
, And are back-to-back with the curved portions 18a, 18b of the streak-like projection 16 on the other side in the circumferential direction.

FIG. 7 is a front view showing a fixture 10 according to still another embodiment of the present invention.
Flange part 1 whose outside diameter is larger than the other part at one end
3 are formed, and two resin biting portions 15a and 15b are formed with the annular groove 14 interposed therebetween. Each of the resin digging portions 15a and 15b is formed with a streak projection 16 having curved portions on both end sides as in the case shown in FIG. The bending direction of the both end portions is the streak-like projection 1 in the other resin biting portion 15b axially adjacent to this.
6 is opposite to the bending direction of both end portions.

As described above, by setting the bending directions to be opposite to each other, it is possible to further increase the bonding force between the fixing bracket 10 and the resin member. However, as shown in FIG. 6, the curved portions 18a, 18b
May be curved in the opposite direction in the circumferential direction, and the curved portions 18a, 1 of both the resin biting portions 15a, 15b may be curved.
8b may be the same direction.

FIG. 8 is a view showing a fixing fitting 10 according to still another embodiment of the present invention. A flange is not provided at one end of the fixing fitting 10 and each of the resin biting portions 15a is provided. , 15b are provided with tapered portions 21 at the ends. In this case, the curving directions of the streak-like projections 16 in the respective resin biting portions 15a and 15b are opposite to each other, but may be the same.

The length of the streak-like projection 16 shown in FIGS. 7 and 8 is shorter than that shown in FIGS. Part 18a, 1
The dimensions of 8b are almost the same. In the case shown in FIGS. 1 to 6, the length of the central portion 17 is substantially the same as that shown in FIGS. 7 and 8, and two rows are provided along the circumferential direction without providing the annular groove 14. The bite portion 15 may be formed in the groove.

In each of the above embodiments, common parts are denoted by the same reference numerals. The circumferential pitch of each of the stripe-shaped projections 16 can be set to an arbitrary value.

The present invention is not limited to the above embodiment, and it goes without saying that various changes can be made without departing from the spirit of the present invention.

For example, the curved portions 18a and 18b of each streak projection 16 are curved in the same direction in the circumferential direction, but one curved portion 18a is turned rightward as shown in FIG. It may be curved and the other curved portion 18b may be curved to the left. If both end portions are curved more circumferentially than the other portions, the streaky projection 16 including the central portion is entirely bent. You may make it curve smoothly. A female screw 11 for screwing a screw member is formed at the center of the fixing bracket 10, but a straight shaft hole may be formed without forming a female screw in place of the female screw hole. When a pin is attached to the shaft hole or when the screw member is attached to the straight shaft hole, a female screw may be cut into the shaft hole like a tapping screw. Further, the shaft hole may be a bottomed hole without opening the end facing the resin side.

[0027]

According to the fixing bracket of the present invention, the engagement groove is formed by the arc-shaped surface of the streak-like projection and does not have a sharp projection. Even when cooling shrinkage occurs, stress concentration is prevented from occurring in the resin member. This prevents cracks and cracks from occurring in the resin member,
The durability of the resin member can be improved. Since the streak-like projections are curved at both ends in the circumferential direction, the fixing bracket and the resin member are firmly fixed by the engagement groove, and the shaft is provided between the resin member and the fixing bracket. Even if an external force in the direction is applied, it is possible to reliably prevent the fixing fitting from being detached from the resin member.

[Brief description of the drawings]

FIG. 1 is a front view showing a fixing bracket according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 in FIG.

FIG. 3 is a sectional view taken along line 3-3 in FIG.

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

FIG. 5 is a cross-sectional view showing a state in which the fixture is embedded in a resin member.

FIG. 6 is a front view showing a fixing bracket according to another embodiment of the present invention.

FIG. 7 is a front view showing a fixture according to still another embodiment of the present invention.

FIG. 8 is a front view showing a fixing bracket according to still another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Female screw 12 Hardware main body 13 Flange part 14 Annular groove 15, 15a, 15b Resin biting part 16 Streak projection 17 Central part 18a, 18b Curved part 19 Engaging groove 20 Resin member 21 Tapered part

Claims (3)

[Claims] 1. A fixing bracket embedded in a resin member, wherein a shaft hole to which a shaft member is attached is formed, and a cylindrical metal body having a resin biting portion on an outer peripheral portion; A plurality of streak-like projections formed on the outer peripheral surface of the resin biting portion and having both ends in the axial direction curved in the circumferential direction; the surface of the streak-like protrusion is formed in an arc shape; A fixing groove formed between adjacent ones of the streaked projections and surrounded by an arc-shaped surface of the streaked projection. 2. The fixing fitting according to claim 1, wherein the fitting main body has a plurality of resin biting portions separated through an annular groove, and a bending direction at both ends of the streak-like projection is set in an axial direction. Wherein the one of the resin biting portions and the other of the resin biting portions adjacent to each other have opposite directions. 3. The fixing bracket according to claim 1, wherein said shaft hole is a female screw to which a screw member is screwed.