JPH0215041Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a housing for a booster comprising a pair of shells connected together.

[Prior art]

The housing of a booster such as a brake booster is constructed by combining a first shell formed in a cup shape and a second shell inserted into an opening of the first shell. Usually, after both shells are painted separately, the second shell is placed inside the first shell, and the opening end of the first shell is caulked from the outer circumferential side (Tokukoku Sho 39- 29403). The caulked portion of the first shell opening is cut from the cylindrical main body and projects radially inward to prevent the second shell from slipping out of the first shell opening.

The cut surface created by such caulking exposes the unpainted metal surface, which is unfavorable in terms of appearance, and there is also a risk that rust will occur if moisture adheres to this portion. moreover,
The cut surface of this caulking and the end surface of the shell formed by press punching and drawing process both have sharp edges, so they may come into contact with cables, wires, etc. placed around the booster. There was a risk of damaging these.

[Summary of the idea]

The present invention has been developed in view of the above drawbacks, and includes the portion where the first shell and the second shell are caulked together, that is, from the outer periphery of the opening of the cup-shaped first shell to the end face on the opening side thereof, and the opening. By providing a protective member that covers the inner surface of the housing, the housing itself and its surroundings are protected, and a housing for the booster that is preferable in terms of appearance is provided.

[Example of idea]

Hereinafter, the present invention will be explained based on illustrated embodiments. FIG. 1 shows a brake booster, and in particular shows the structure of the connecting portion of its housing in cross section. The housing 1 of the brake booster includes a first shell 2 on the front side and a second shell 3 on the rear side.
The inside of this housing 1 includes an outer peripheral portion 4 at the joint portion of the first and second shells 2 and 3.
A is divided into front and rear pressure chambers 5 and 6 by a diaphragm 4 which is held between the pressure chambers 5 and 6. This brake booster operates by controlling the opening and closing of a conventionally known valve mechanism (not shown).
A pressure difference is created between them to perform a boosting mechanism.

The first shell 2 is formed into a cup shape, and an enlarged diameter portion 8 is provided at an open end 2a via a step portion 7. On the other hand, the second shell 3 is formed into a disk shape or a shallow dish shape, and the outer diameter of the outer peripheral flange portion 9 is set to substantially match the inner diameter of the enlarged diameter portion 8. The connection between these two shells 2 and 3 is carried out as follows. First, the outer peripheral flange portion 9 of the second shell 3 is inserted into the enlarged diameter portion 8 of the first shell 2, and after this flange portion 9 is brought into contact with the stepped portion 7 of the first shell 2, the enlarged diameter portion 8 is inserted. By caulking from the outside in the radial direction, the second shell 3 is prevented from moving toward the outside of the opening of the first shell 2. The above-mentioned caulking connection is usually performed at a plurality of locations equally spaced in the circumferential direction of the enlarged diameter portion 8, and as shown in FIG. It is cut leaving a portion having a height approximately equal to the thickness t of 9, and is formed as a protrusion 10 facing radially inward.
As a result, the flange portion 9 of the second shell 3 is held between the step portion 7 of the first shell 2 and the projection 10, and both shells 2 and 3 are fastened together. Although not shown, the flange portion 9 of the second shell 3 is formed with the same number of notches at equal intervals to the spacing between the plurality of protrusions 10, and when the second shell 3 is rotated, these protrusions 10 are formed. By aligning the positions of the notches with the shells 2 and 3, both shells 2 and 3 can be disassembled and repaired.

In the housing 1 according to this embodiment, as shown in an enlarged view in FIG. 3, the area where the two shells 2 and 3 are connected is covered with a protective member 11. This protective member 11 includes a surface 12 cut by caulking and an end surface 13 on the opening side of the first shell 2 (see FIG. 2).
from the inner surface of the enlarged diameter section 8 to the end surface 13, the outer surface of the enlarged diameter section 8, and the stepped section 7.
It covers all the way to the outside. The protective member 11 is made of a soft material such as rubber or vinyl chloride, and therefore expands in the radial direction at the protrusion 10 formed by caulking to cover both the inner and outer surfaces. By covering the outer periphery of the portion where both shells 2 and 3 are joined by caulking with the protective member,
Unpainted surface 1 cut by caulking
2, and in particular can prevent water droplets from adhering to the inner surface of the caulked portion. Further, it is also possible to protect peripheral cables and the like that may be damaged by the cut surface 12 and the opening side end surface 13 of the first shell 2. In this embodiment, a material such as rubber is extruded into the above-mentioned cross-sectional shape and then formed into an annular shape, which is then fitted. However, a protective member formed by other means may be attached.

[Effect of idea]

As described above, in the present invention, by providing a protective member that covers from the outer periphery of the caulking joint at the opening end of the first shell to the opening side end surface and the inner surface of the opening, this protection is achieved. The member does not easily come off from the shell opening end, and
It is possible to reliably prevent moisture from entering the caulked part from the inner peripheral surface of the opening, and by coating it in this way, it is also desirable in terms of appearance,
In addition, it is possible to prevent the occurrence of rust, and also to provide a protective function such as eliminating the possibility that the cut surface and the end surface of the shell will damage cables and the like disposed around the shell.

[Brief explanation of the drawing]

Fig. 1 is a partially sectional side view showing an embodiment of the present invention, Fig. 2 is a perspective view showing a part of the joint between the first and second shells, and Fig. 3 is the same as Fig. 1. FIG. 3 is an enlarged cross-sectional view of main parts. 2: first shell, 2a: open end of first shell,
3: second shell, 11, 14: protection member.

Claims (1)

[Scope of utility model registration request] The second shell is inserted into the opening of the cup-shaped first shell, the open end of the first shell is caulked, and a part of the open end is cut radially inward, thereby joining both shells. A housing for a booster comprising: a protective member covering from the outer periphery of the caulked joint at the opening end of the first shell to the opening-side end surface thereof and the inner surface of the opening; housing.