JP2004052962A - Drum brake and its shoe hold-down - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve such a problem that assembly work is troublesome because of a large number of part items. <P>SOLUTION: A shoe hold-down comprises a spring working section foe elastically enforcing a shoe to a back plate, a locking section to lock the shoe to the back plate, and a shaft connecting a spring working section and the locking section. The spring working section, the locking section and the shaft are integrally formed of plate spring material. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a drum brake for an automobile and the like and a shoe hold down thereof.
[0002]
[Prior art and its problems]
First, a conventional drum brake for an automobile and the like and a shoe hold down thereof will be described with reference to FIGS.
[0003]
For example, as shown in FIG. 1, a drum brake 10 used in an automobile includes linings 14, 15 fixed to shoes 16, 18 arranged so as to be able to contact and separate a back plate 12 and a drum 25. , 15 to contact the drum 25 and a shoe return spring 26 to force it apart and a shoe hold-down 22 to force the shoes 16 and 18 toward the back plate 12.
[0004]
The back plate 12 is fixed to the vehicle body. The drum 25 is connected to wheels and rotates as the vehicle travels.
[0005]
The shoes 16 and 18 are pivotally connected to an anchor 24 fixed to the back plate 12, and are forced away from the drum 25 by a shoe return spring 26.
[0006]
The wheel cylinder 20 is, for example, supplied with hydraulic pressure to spread the shoes 16 and 18 against the force of the shoe return spring 26 and press the drum 16 against the drum 25 to apply braking to the wheels.
[0007]
The shoe holddown 22 forces the shoes 16 and 18 toward the backplate 12 to prevent the shoes 16 and 18 from lifting off the backplate 12.
[0008]
Conventionally, as shown in FIG. 2, the shoe hold down 22 is disposed, for example, between a shaft 30 having a stopper 28 that engages with the back plate 12, two upper and lower sheets 32 and 34, and the sheets 32 and 34. The spring 36, i.e., four parts. When the shoe hold down 22 is installed, the shaft 30 is inserted through the hole 38 of the back plate 12 and the hole 40 of the shoe 16, the lower sheet 32, the spring 36, and the upper sheet 34 are arranged, and The rectangular top portion 44 of the shaft 30 is projected from the rectangular hole 42 of the sheet 34, and the top portion 44 is twisted by 90 ° with a tool such as a plier, and is installed so that the shaft 30 does not come off as shown in FIG.
[0009]
Such a conventional shoe hold-down 22 has the disadvantage that the number of parts is large and the assembling workability is troublesome as described above.
[0010]
[Means for Solving the Problems]
According to the present invention, in order to solve the above problems,
A back plate, a lining fixed to a shoe arranged to be able to contact and separate from the drum, a wheel cylinder forcing the lining to contact the drum, a shoe return spring for forcing the lining to separate, and the shoe; Equipped with a shoe hold down to force towards the back plate,
The shoe hold-down includes a spring action portion for elastically forcing the shoe toward the back plate, a locking portion for locking the shoe to the back plate, and a spring action portion and the locking portion. With a connecting shaft,
A drum brake is provided, wherein the spring action portion, the locking portion, and the shaft of the shoe hold down are integrally formed of a leaf spring material.
[0011]
According to the present invention, in order to solve the above problems,
In the shoe hold down that forces the shoe in the drum brake toward the back plate,
A spring acting portion for elastically forcing the shoe toward the back plate, a retaining portion for retaining the shoe to the back plate, and a shaft connecting the spring acting portion and the retaining portion. With
A shoe holddown is provided, wherein the spring action portion, the locking portion, and the shaft are integrally formed of a leaf spring material.
[0012]
【Example】
Next, a drum brake and a shoe holddown according to the first embodiment of the present invention will be described with reference to FIGS.
[0013]
This drum brake 110 has a lining 114 fixed to a back plate 112, a shoe 116 arranged so as to be able to contact and separate from the drum 125, and the lining 114 to the drum 125, similarly to the drum brake shown in FIG. It has a wheel cylinder that forces it into contact, a shoe return spring 126 that forces it away, and a shoe holddown 122 that forces the shoe toward the backplate 112.
[0014]
The shoe hold-down 122 includes a spring action portion 150 for elastically forcing the shoe 116 toward the back plate 112, an engagement portion 152 for engaging the back plate 112, a spring action portion 150 and the engagement portion 152. And a shaft 154 connecting the spring action part 150, the locking part 152, and the shaft 154 are integrally formed of a leaf spring material.
[0015]
The shoe hold-down 122 is formed by, for example, punching a metal leaf spring material into a shape as shown in FIG. 4 by press working, and working and forming as shown in FIG.
[0016]
The shaft 154 of the shoe hold-down 122 made as shown in FIG. 5 is advanced through the hole 140 of the shoe 116 and the hole 138 of the back plate 112 as shown in FIG. Thereby, the locking portion 152 is locked to the back plate 112.
[0017]
As shown in FIGS. 3 and 5, the hole in the back plate 112 has a wide rectangular portion through which the wide locking portion 152 can pass, and a circular portion where the twisted shaft 154 is located.
[0018]
FIGS. 6 to 8 are views showing a deployed state of the shoe hold downs 60, 62 and 64 according to the second to fourth embodiments, and a state after processing and molding.
[0019]
The shoe hold-downs 60, 62 and 64 according to these embodiments differ from the shoe hold-down 122 according to the first embodiment in the shape of the respective spring action portions.
[0020]
FIGS. 9 to 12 are views showing the expanded state of the shoe hold downs 66, 68, 70 and 72 according to the fifth to eighth embodiments.
[0021]
The shoe hold-downs 66, 68, 70, and 72 according to these embodiments differ from the shoe hold-down 122 according to the first embodiment in the shape of the respective spring action portions.
[0022]
FIG. 13 is a diagram showing a deployed state of the shoe hold down 74 according to the ninth embodiment and a side view thereof.
[0023]
The shoe hold-down 74 according to this embodiment differs from the shoe hold-down 122 according to the first embodiment in the shape of each spring acting portion. Further, the spring action portion of the shoe hold down 74 according to this embodiment has an elongated rib 76 as shown. That is, for example, an elongated concave portion is formed on one side by pressing, and an elongated convex portion corresponding to the elongated concave portion is formed on the other side. By providing such a rib 76, the spring strength can be increased even with the same material.
[0024]
FIGS. 14 to 16 are views showing an expanded state of the shoe hold downs 78, 80 and 82 according to the tenth to twelfth embodiments.
[0025]
The shoe holddowns 78, 80, and 82 according to these embodiments are different from the shoe holddown 122 according to the first embodiment in the shape of the respective spring acting portions, and are the same as the ninth embodiment shown in FIG. It has various ribs.
[0026]
FIG. 17 is a diagram showing an expanded state of the shoe hold down 84 according to the thirteenth embodiment.
[0027]
The shoe hold-down 84 according to this embodiment differs from the shoe hold-down 122 according to the first embodiment in the shape of the spring action portion. Further, the spring action portion of the shoe hold down 84 according to this embodiment has an opening 86 in the spring action portion as shown. By having such an opening 86, the weight can be reduced.
[0028]
FIGS. 18 to 20 are views showing an expanded state of the shoe hold downs 88, 90 and 92 according to the fourteenth to sixteenth embodiments.
[0029]
The shoe holddowns 88, 90, and 92 according to these embodiments differ from the shoe holddown 122 according to the first embodiment in the shape of the respective spring acting portions, and are similar to the thirteenth embodiment shown in FIG. It has a nice opening.
[0030]
FIG. 21 is a diagram showing the locking portion 96 of the shoe hold down 94 according to the seventeenth embodiment.
[0031]
The locking portion 96 of the shoe hold-down 94 according to this embodiment includes deflecting portions 98 and 100 deflected to the left and right, as shown. When the locking portion 96 is inserted into the elongated hole 102 provided in the back plate and passes through the elongated hole 02, the deflection portions 98 and 100 are located on the left and right sides of the elongated hole 102 due to its elasticity. Therefore, the shoe holddown 94 can be locked to the back plate only by inserting the locking portion 96 into the elongated hole 102.
[Brief description of the drawings]
FIG. 1 is a plan view of a conventional drum brake and its shoe hold down.
FIG. 2 is a plan view and a front view of a main part of the drum brake of FIG. 1;
FIG. 3 is a plan view and a front view of a drum brake and a shoe hold down thereof according to a first embodiment of the present invention.
FIG. 4 is a developed view of the shoe hold-down shown in FIG. 3;
FIG. 5 is a diagram showing the processed shoe hold-down shown in FIG. 3 and a hole into which a locking portion is inserted.
FIG. 6 is a diagram showing a developed state of a shoe hold-down according to a second embodiment and a state after work molding.
FIG. 7 is a view showing a developed state of a shoe hold-down according to a third embodiment and a state after work forming.
FIG. 8 is a view showing a developed state of a shoe hold-down according to a fourth embodiment and a state after work forming.
FIG. 9 is a diagram showing an expanded state of a shoe hold-down according to a fifth embodiment.
FIG. 10 is a diagram showing an expanded state of a shoe hold-down according to a sixth embodiment.
FIG. 11 is a diagram showing an expanded state of a shoe hold-down according to a seventh embodiment.
FIG. 12 is a view showing an expanded state of a shoe hold down according to the eighth embodiment.
FIGS. 13A and 13B are a plan view and a side view of a shoe hold down according to a ninth embodiment in a developed state.
FIG. 14 is a diagram showing an expanded state of shoe hold down according to the tenth embodiment.
FIG. 15 is a diagram showing an expanded state of shoe hold down according to the eleventh embodiment.
FIG. 16 is a diagram showing an expanded state of a shoe hold-down according to a twelfth embodiment.
FIG. 17 is a diagram showing an expanded state of a shoe hold-down according to a thirteenth embodiment.
FIG. 18 is a diagram showing an expanded state of a shoe hold-down according to a fourteenth embodiment.
FIG. 19 is a diagram showing an expanded state of a shoe hold-down according to a fifteenth embodiment.
FIG. 20 is a diagram showing an expanded state of a shoe hold-down according to a sixteenth embodiment.
FIG. 21 is a view showing locking portions of a shoe hold down and holes of a back plate according to a seventeenth embodiment.
FIG. 22 is a diagram showing a locked state of a shoe hold-down according to a seventeenth embodiment.
[Explanation of symbols]
110 Drum brake 112 Back plate 114 Lining 116 Shoe 122 Shoe hold down 125 Drum 150 Spring action part 152 Lock part 154 Shaft

Claims (2)

A back plate, a drum, a lining fixed to a shoe arranged so as to be able to contact and separate from the drum, a wheel cylinder forcing the lining to contact the drum, a shoe return spring for forcing the lining to separate, and the shoe A shoe hold down forcing the back plate toward
The shoe hold-down includes a spring action portion for elastically forcing the shoe toward the back plate, a locking portion for locking the shoe to the back plate, and a spring action portion and the locking portion. With a connecting shaft,
A drum brake, wherein the spring action portion, the locking portion, and the shaft of the shoe hold down are integrally formed of a leaf spring material. In the shoe hold down that forces the shoe in the drum brake toward the back plate,
A spring acting portion for elastically forcing the shoe toward the back plate, a retaining portion for retaining the shoe to the back plate, and a shaft connecting the spring acting portion and the retaining portion. With
The shoe hold-down, wherein the spring action portion, the locking portion, and the shaft are integrally formed of a leaf spring material.

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