JP2000177489A - Housing for door mirror - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a housing for a door mirror allowing accurate driving of a tilt-driving device without requiring any mini brackets, allowing reduction in a cost and a weight of a door mirror, and allowing improvement of flexural rigidity. SOLUTION: This housing for a door mirror has a mirror plate disposed in an opening part 1a, and a tilt-driving device 2 within the housing, while the tilt-driving device 2 can be tilted in the back-and-forth direction of a vehicle body and can change vertical and right-and-left tilt angles of the mirror plate. A rear face part 1b facing to the opening part 1a is formed by gas-assist injection molding in a two-layer structure 5 comprising an outer wall part 5b and an inner wall part 5c facing to each other in the thickness direction with a single hollow part 5a interposed. The two-layer structure 5 can increase a substantial thickness of the rear face part 1b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a door mirror housing mounted on an automobile.

[0002]

2. Description of the Related Art A housing of this kind is generally made of ABS.
It is integrally formed using a resin material. However, it has been pointed out that the molded product of the housing not only has an unfavorable appearance due to the occurrence of sink marks on the thick portion, but also has a residual stress in the thick portion and poor impact resistance.

[0003] Therefore, as a molding method of the housing, adoption of a gas assist injection molding method has been conventionally proposed.

[0004] That is, JP-A-8-25516 discloses a process of injecting a resin which is heated and melted into a mold having a negative cavity of a door mirror body (corresponding to a door mirror housing) to form a door mirror body. After the resin is injected and when the resin in the thick portion is in a softened state, a gas is blown into the thick portion to form a hollow inside the thick portion, and simultaneously, the resin around the hollow portion is applied toward the mold cavity wall surface. A method of manufacturing a door mirror body including a pressing step has been proposed. According to this manufacturing method, a molded article does not generate residual stress, and although a hollow part is formed, the hollow part is formed. It is stated that the strength of the thickened portion can be increased, and even if an external impact is applied thereto, the portion is not easily broken.

Japanese Patent Application Laid-Open No. 9-57784 discloses that
A raised portion is formed to connect between the base of the boss and a gas injection portion for performing hollow injection molding or a thick portion of the injection molded part, and after a predetermined cooling time has elapsed, gas is injected from the gas injection portion to form the boss. There has been proposed a method of manufacturing an injection molded part (housing for a door mirror) which forms a hollow part communicating with the inside of a base, the inside of a gas injection part, or the inside of a raised part connecting to a thick part of the injection molded part. According to this manufacturing method, it is possible to take measures against sink marks on the surface of the injection-molded part and to reduce the cycle time during molding.

Further, Japanese Patent Application Laid-Open No. 9-58345 discloses that a continuous portion of a portion connected to a base fixed to a vehicle body and a visor portion for supporting a door mirror to be able to tilt forward and backward is formed by a gas assist injection molding method. There has been proposed a door mirror housing formed in a hollow shape. According to this housing, the gap between the inner peripheral surface of the visor portion and the outer peripheral edge of the mirror plate can be reduced, and molding defects such as sink marks occur. Can be prevented.

[0007]

SUMMARY OF THE INVENTION These conventional techniques are:
The common problem is to prevent the occurrence of sink marks on the thick part of the door mirror housing (elimination of residual stress), to improve the strength of the thick part (JP-A-8-25516), and to reduce the cycle time during molding. Japanese Unexamined Patent Publication No. Hei 9-58345, and Japanese Patent Application Laid-Open No. Hei 9-58345, and Japanese Patent Laid-Open Publication No.
No. 1), and no proposal has been made for improving the torsional rigidity of the housing.

[0008] As described above, the prior art has no idea about improving the torsional rigidity of the housing.

[0009] However, if the torsional rigidity of the housing is not sufficient, it is not possible to ensure accurate driving of the tilt driving device mounted in the housing.

For this reason, in the conventional door mirror, it is natural that the torsional rigidity of the housing is insufficient, and as shown in FIG.
At the time of installation inside, the mini bracket 50 is mounted in the tilt drive device 2 to reinforce it.

That is, the tilt driving device 2 is provided with a mirror plate 3
A first drive unit 21 for tilting the entire housing 1 on which the mirror plate 3 is mounted in the front-rear direction of the vehicle body (not shown) around the rotation shaft 4, and a second drive unit for changing the vertical and horizontal tilt angles of the mirror plate 3 And a drive unit 22 and a mini-bracket 50 (shown with diagonal lines in FIG. 5).
Is mounted so as to connect the first drive unit 21 and the second drive unit 22. The mini bracket 50 is formed of, for example, glass fiber reinforced plastic.

Therefore, the conventional door mirror has a problem that the number of parts and the number of assembling steps are increased due to the necessity of the mini-bracket 50, which leads to an increase in weight and cost.

Therefore, the present invention can ensure accurate driving of the tilting drive device without the need for a mini-bracket, and can also reduce the weight and cost of the door mirror. It is an object of the present invention to provide a housing for a door mirror.

[0014]

In order to achieve the above object, a first aspect of the present invention is to dispose a mirror plate facing an opening and tilt the interior of the vehicle in the longitudinal direction of a vehicle body. A housing of a door mirror in which a tilt driving device for changing a tilt angle of a mirror plate in a vertical direction and a horizontal direction is disposed, and a rear portion facing the opening has a single hollow portion formed by a gas assist injection molding method. It is characterized by having a two-layer structure consisting of an outer wall portion and an inner wall portion that face each other in the thickness direction.

Therefore, according to the first aspect of the present invention, the substantial thickness of the back portion (the thickness of the outer wall portion + the thickness of the inner wall portion) is increased by the two-layer structure formed on the back portion. Accordingly, the torsional rigidity of the housing can be improved. Due to the improvement of the torsional rigidity, the tilting driving device mounted on the housing can ensure accurate driving without requiring reinforcement by the mini bracket.

Further, the two-layer structure can be easily formed at the same time as the housing is formed by the gas-assisted injection molding method without the appearance of sink marks.

According to a second aspect of the present invention, there is provided the door mirror housing according to the first aspect, wherein the two-layer structure includes:
It is characterized in that it is formed in a substantially half portion of the rear portion that is closer to the vehicle body.

According to the second aspect of the present invention, when the door mirror is mounted on the vehicle body, the torsional rigidity of a substantially half portion of the housing close to the vehicle body can be improved by the formed two-layer structure. As a result, the torsional rigidity of the proximal end where a load is applied within the housing is improved, and accurate driving of the tilt drive device can be ensured.

Further, since the two-layer structure is formed partially on the rear surface of the housing, it is possible to suppress an increase in the weight of the housing itself.

[0020]

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

FIGS. 1A and 1B show a door mirror housing 1 according to an embodiment of the present invention. The housing 1 is arranged with the mirror plate 3 facing the opening 1a, and is internally tilted in the front-rear direction of the vehicle body (not shown) and changes the tilt angle of the mirror plate 3 in the vertical and horizontal directions. The main part of the door mirror is configured by disposing the tilt drive device 2.

At this time, the tilt driving device 2 is the whole of the housing 1 on which the mirror plate 3 is mounted (the main part of the door mirror).
A first drive unit 21 for tilting the vehicle body (not shown) around the rotation shaft 4 in the front-rear direction, and a second drive unit 22 for changing the vertical and horizontal tilt angles of the mirror plate 3. The first and second drive units 21 and 22 are attached to the housing 1.

As shown in FIGS. 2 to 4, the housing 1 has a back surface 1b facing the opening 1a in a thickness direction through a single hollow portion 5a formed by gas assist injection molding. And has a two-layer structure 5 composed of an outer wall portion 5b and an inner wall portion 5c opposed to each other. The two-layer structure 5 is shown by hatching in FIG.

The two-layer structure 5 preferably has the structure shown in FIG.
As shown in FIG. 2, the rear portion 1b of the housing 1 is formed in a substantially half portion near the vehicle body.

The two-layer structure 5 is formed simultaneously with the molding of the housing 1 by a known gas assist injection molding method using an ABS resin material.

In the present embodiment, the two-layer structure 5 has a single hollow portion 5a formed as a gas channel for gas injected from the gas injection port 6 and occupying substantially half of the back portion 1b. An outer wall portion 5b and an inner wall portion 5c which face each other in the thickness direction via the hollow portion 5a.

The gas channel 11 formed starting from the gas inlet 6 further includes boss portions 7, 8, 9, 1
0 and a hollow portion 12 (see FIG. 1) as a gas channel on the lower side wall of the housing 1 so that the bosses 7, 8, 9, 10 and the lower side wall of the housing 1 can be made thicker. The part can be formed without the appearance of sink marks. The boss portions 7 and 10 are formed on the inner wall portion 5c of the two-layer structure 5, and the boss portions 8 and
9 is a thin portion 1 of the back portion 1b where the two-layer structure 5 is not formed.
d (see FIG. 2).

The tilt drive 2 is attached to the housing 1 thus formed.

That is, as shown in FIG.
The drive unit 21 is mounted on the lower side wall of the housing 1 by tightening a screw (only the screw 19 is shown), and the second drive unit 22 is mounted on the bosses 7, 8, 9, 10
Are attached to the rear surface 1b of the housing 1 by screws 15, 16, 17, and 18, respectively.

Further, the mirror plate 3 is disposed so as to face the opening 1a of the housing 1, and is supported by a ball joint 22a of the second drive unit 22 so as to be capable of tilting vertically and horizontally. By attaching the tilt drive device 2 and the mirror plate 3 to the housing 1 in this manner, a main part of the door mirror can be formed, and this main part is fixed to a mounting seat provided at a corner of a door of an automobile. Base (not shown)
In addition, a door mirror can be configured by being attached to a vehicle body (not shown) so as to be tiltable in the front-rear direction.

In the door mirror configured as described above, the housing 1 has a two-layer structure 5 formed on the back surface 1b, and the substantial thickness of the back surface 1b (the thickness of the outer wall 5b + the inner wall). 5c), and the torsional rigidity is improved. Therefore, the tilting driving device 2 mounted on the housing 1 can be accurately mounted without requiring reinforcement by the mini bracket (the conventional mini bracket 50). Driving can be secured. The back part 1b at this time
The weight increase corresponding to the substantial increase in the thickness of the conventional mini-bracket is negligible.

As described above, the housing 1 allows the tilt drive device 2 to be mounted without the need for a mini-bracket by improving its torsional rigidity. Therefore, the number of parts as a door mirror and the assembling of the door mirror are reduced by eliminating the mini-bracket. The number of man-hours can be reduced, and the weight and cost of the door mirror can be reduced.

The two-layer structure 5 can be easily formed at the same time as the housing 1 is formed by the gas-assisted injection molding method without the appearance of sink marks. For this reason, the housing 1 can be easily molded without the difficulty of molding.

When the door mirror is mounted on the vehicle body, the housing 1 can improve the torsional rigidity of substantially half of the housing 1 closer to the vehicle body by the formed two-layer structure 5. 1, the torsional rigidity of the base end 1c (see FIGS. 1 and 2) to which a load is applied is improved, and accurate driving of the tilt drive device 2 can be ensured.

Further, since the two-layer structure 5 is formed partially on the rear surface 1b of the housing 1, it is possible to suppress an increase in the weight of the housing 1 itself, thereby further reducing the weight of the door mirror. be able to.

[0036]

As described above, according to the first aspect of the present invention, the torsional rigidity of the housing can be improved by the two-layer structure formed on the back surface, so that a mini bracket is not required. Accurate driving of the tilt drive unit can be ensured, and the number of parts and assembling man-hours as a door mirror can be reduced by eliminating the need for a mini-bracket.Thus, the weight and cost of the door mirror can be reduced. Can be planned.

According to the second aspect of the present invention, when the door mirror is mounted on the vehicle body, the torsional rigidity of a substantially half portion of the housing close to the vehicle body can be improved by the formed two-layer structure. Thus, the torsional rigidity of the proximal end of the housing where a load is applied is improved, and accurate driving of the tilt drive device can be ensured.

In addition, since the two-layer structure is partially formed on the rear surface of the housing, it is possible to suppress an increase in the weight of the housing itself, thereby further reducing the weight of the door mirror. it can.

[Brief description of the drawings]

FIG. 1A is a plan view of a main part of a door mirror using a housing according to an embodiment of the present invention.
(B) is sectional drawing which follows the Ib-Ib line of (a).

FIG. 2 is a front view of a housing used for a main part of the door mirror in FIG. 1;

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 2;

5A is a plan sectional view of a main part of a conventional door mirror, and FIG. 5B is a sectional view taken along line Vb-Vb of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 1a Opening part (of housing) 1b Back part (of housing) 2 Tilt drive 3 Mirror plate 5 Double-layer structure 5a Hollow part (of two-layer structure) 5b Outer wall part (of two-layer structure) 5c Inner wall part (Two-layer structure)

Claims (2)

[Claims] 1. A door mirror in which a mirror plate is arranged facing an opening, and a tilt drive device for tilting the mirror plate in the front-rear direction and changing the vertical and horizontal tilt angles of the mirror plate is disposed therein. A housing having a back surface facing the opening, a two-layer structure including an outer wall portion and an inner wall portion opposed in a thickness direction via a single hollow portion formed by a gas-assisted injection molding method. A housing for a door mirror, which is formed with a structure. 2. The door mirror housing according to claim 1, wherein the two-layer structure is formed in a substantially half portion of the rear surface portion that is closer to the vehicle body. Housing.