JP2557637Y2 - Drum brakes for vehicles - Google Patents

Description

[Detailed description of the invention]

[0001]

INVENTION The present invention relates, regarding <br/> the vehicle drum brake having an anchor serving as the rotation fulcrum of the brake shoe.

[0002]

2. Description of the Related Art An anchor for a vehicle drum brake is disclosed, for example, in Japanese Utility Model Laid-Open No. 2-117438. In this anchor, an anchor body with which a pair of brake shoes abut, an ear portion for preventing the brake shoes from coming off, and a leg portion fixed to the back plate punches a thick metal flat plate in a thickness direction by a press. The structure required for the anchor can be manufactured in a stamping step of a press.

[0003]

However, in the above-mentioned method, the anchor cannot be made thicker than a predetermined thickness because there is a limit to the thickness of a metal flat plate that can be punched out by a press. For this reason, it is difficult to secure high rigidity to the anchor, and it is not suitable for a drum brake that generates a high torque.

[0004] The present invention is to ensure a high rigidity and attachment strength to the anchor formed by the single plate, that are subjected Hisage <br/> drum brake that can be applied to a drum brake of the high torque The purpose is.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, a vehicle drum brake according to the present invention has an actuation mechanism provided between one end of a pair of brake shoes arranged opposite to a back plate.
Arrange the tutor, anchor between the other end,
In a vehicle drum brake in which a pair of brake shoes are opened by an actuator with the anchor as a fulcrum to perform a braking operation, the anchor is folded back at a central portion of a metal plate.
To form a double plate structure with the plate portions facing each other,
Anti respective folded end face with projecting legs, two plates of
With but fixed to the back plate legs to be disposed radially inside and outside of the back plate, said anti-folding of both the plate portion
Ri to both side plates Atsutan surface perpendicular to the return-side end face, is characterized in that contact against the other ends of a pair of brake <br/> Kishu.

[0006]

According to the above structure, the anchor has a double plate structure.
Both plates are located inside and outside the back plate in the radial direction.
The back leg is fixed to the back plate.
In both the radial direction of the sheet and the direction perpendicular to it.
Harder to mount and greater mounting strength than single-plate anchors
Degree .

Further, while using a metal plate having a thickness that can be punched by a press, the punched metal plate is folded in two .
The brake shoe
Doubling the contact area of the
Can be

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments in which the present invention is applied to a drum brake used in a golf car will be described below with reference to the drawings.

[0009] FIGS. 1 to 4 show a first embodiment of the present invention, the drum brake 1, the backplate of arcuate disposed to face the inside of the second brake shoe 3a, 3b one <br/> actuator 4 for expanding between the ends, the two shoes 3a between the other end portion, the anchor 5 to be expanded fulcrum 3b are respectively <br/> arranged.

The back plate 2 has a small diameter for the generated torque since the drum brake 1 of the present embodiment is applied to the golf car as described above, so that the mounting space is small and restricted. For this reason, a braking force necessary for a golf car is ensured by forming it from a high-rigidity, high-tensile steel plate that is not likely to be deformed even when subjected to a high torque.

In one brake shoe 3a, one end of a shoe web 3c abuts a brake lever 4b pulled by a wire (not shown), and the other end abuts an anchor 5. The other brake shoe 3 b has one end of the shoe web 3 c connected to the adjustment bolt 4 of the actuator 4.
d and the other end is in contact with the anchor 5. A lining 3e is attached to the outer periphery of each shoe rim 3d of the brake shoes 3a, 3b, and the linings 3e , 3e are in sliding contact with the inner peripheral surface of a brake drum (not shown) rotating in the direction of arrow A in FIG. To perform the braking action. The brake shoes 3a and 3b have a substantially central portion formed by a shoe hold down pin 6a and a shoe hold spring 6b.
b, it is resiliently held by the back plate 2 and is urged by the return springs 7 and 8 in the diameter reducing direction.

The actuator 4 referred to in the present embodiment includes, in addition to the sliding block 4a, a brake lever 4b, an adjustment gear 4c and an adjustment bolt 4d which is extended by rotation of the gear 4c, and one end of the actuator 4 abuts on the brake lever 4b. The other end includes an adjusting lever 4e that meshes with the adjusting gear 4c to rotate the adjusting gear 4c, and a spring 4f that elastically engages the levers 4b, 4e, and slides with the rotation of the brake lever 4b. Block 4a
The brake shoes 3a and 3b are expanded by the sliding of. Further, the above-described adjustment gear 4c, adjustment bolt 4d, adjustment lever 4e and spring 4
f, an auto adjuster is formed, and the lining 3e
Is worn out and the braking gap with the brake drum expands more than a predetermined amount, the adjusting bolt 4d is extended to restrict the retreat limit of the brake shoes 3a and 3b so that the predetermined braking gap is automatically obtained. I have.

The anchor 5 is formed by punching a single high-tensile steel plate symmetrically with a press at a folding line and sandwiching the folding line at the center , folding the plate in two at the central folding line, and joining the plate portions 5a with each other.
Which was formed on the double plate structure with opposing both plate portions 5
a, 5a, both plate portions 5 continuing on the anti-folding side
pedestals 5b, 5b wider than the pedestals 5a, 5a ;
Part 5b, anti-aliasing side end face two respective legs 5c of 5b, projecting the 5c, ears on each side plate Atsutan surface of the folded portion
5d, 5d protruding, the anti-folding of both plate portions 5a, 5a
A pair of plate thickness end faces 5e, 5e orthogonal to the
It is the contact surface at the other end of the rake shoe.

The anchor 5 has legs 5c inserted into four mounting holes 2a formed in the back plate 2, and these legs 5c are bent outward by a press.
By caulking and fixing to back plate 2 , both plates
Parts 5a, 5a are arranged inside and outside the back plate 2 in the radial direction
Is done. The ears 5d, 5d are connected to the side plate thickness end faces 5
e, 5e, brake shoes 3a, 3b disengaged
It is a stop, and the attachment of the anchor 5 causes the leg 5 c
On both sides of the folded part that is the contact side when bending the
Thickness end face is made the form by that bulge crushed.
The brake shoes 3a, 3b were mounted in this manner.
The other end of each web 3c is abutted and supported by both plate thickness end surfaces 5e, 5e of both plate portions 5a, 5a . Both plate portions 5 of this embodiment
a, 5a, the back plate 2 by deep drawing difficult high tensile steel, since the protruding amount of deformation of the inside is small, both the plate portion 5
a, 5a and both pedestals 5b , 5b are higher in height than the conventional one, and the webs 3c, 3c of the brake shoes 3a, 3b are positioned approximately in the middle of the height of the two plates 5a, 5a. Is set to abut.

The drum brake 1 thus formed
When the outer end side of the brake lever 4b on the back surface of the back plate 2 is rotated rightward in FIG.
The inner end of b moves leftward, the leading brake shoe 3a expands to the left with the anchor 5 as a fulcrum, and the lining 3e slides on the inner peripheral surface of the brake drum. Further, the slide block 4a moves rightward due to the contact reaction force, and the adjusting bolt 4d is moved to the brake shoe 3 on the trailing side.
Then, the brake lining 3e of the brake shoe 3b is brought into sliding contact with the inner peripheral surface of the brake drum on the opposite side to perform braking.

The brake shoes 3a, 3b are
Since the height of the plate portion 5a is formed relatively high and the lug portion 5d is formed at the turn-back portion when it is expanded at the fulcrum, the plate portion 5a does not come out upward by the expansion / contraction operation during braking. .

Further, the anchor 5 has a double plate structure with two plate portions.
5a, 5a are disposed inside and outside the back plate 2 in the radial direction.
The four legs 5c are fixed to the back plate 2 so that
Therefore, the radial direction of the back plate 2 and the
Hard to fall in any direction of the
Greater mounting strength is obtained . Also, since the anchor 5 is formed by folding a high-tensile steel plate having a thickness that can be punched out by a press, the area of the side end face 5e that comes into contact with the webs 3c, 3c is smaller than that of a conventional anchor having a single-plate structure.
By doubling, the anchor 5 can have high rigidity ,
A stable braking force can be obtained without deformation even when receiving a high torque. Further, since the anchor 5 has the above-described effects, it can be applied to a high-torque drum brake as well as a golf car drum brake having a large braking force for its size, as in the present embodiment. Become.

FIG. 5 shows a second embodiment of the present invention.
The anchor 9 is formed with a relatively low height of both plate portions 9a, 9a , and is provided with ear portions 9 for preventing the detachment at the thick end surfaces on both sides of the folded portion.
b, 9 b which was provided relatively large, the ear portion 9b
Are integrally formed at the time of punching by a press like other parts.

In the above embodiment, the anchor is attached to the back plate by inserting the leg into the mounting hole formed in the back plate, and then bending the leg outward, and then bending the leg inward. It may be crimped, and the fixing of the legs may be performed by welding. Further, the bottom surface of the leg may be directly welded to the inner surface of the back plate, and further, the leg may be bent inward or outward, respectively, and the bent leg may be fixed to the inner surface of the back plate by welding. Good.

Further, in the above-described embodiment, the back plate and the anchor are described as being formed of a high-tensile steel plate. However, it is needless to say that a general steel plate may be used.

[0021]

Effects of the invention] As described on the following, Doramubu for a vehicle according to the present invention
For the rake, the metal plate is folded back at the center
Formed in a double plate structure with the parts facing each other, and the two plate parts are folded back
The legs are projected from the end face on the turning side , and both plates are
Legs to be disposed radially inside or outside of the click plate is fixed to the back plate, the anti-aliasing of the two plate portions
The side plates Atsutan surface perpendicular to the side end face, since the contact against the other end of the pair of brake shoes, the anchor backplate
In both the radial direction of the rate and the direction perpendicular to it
It is difficult to fall down, and it is larger than a single-plate anchor.
Attaching strength is obtained . Further, while using the thickness of the metal plate can be punched in a press, since the punched metal plate can form an anchor by folio, doubling the contact area between the brake shoes, a high rigidity to the anchor
You can have. Further, in this manner, sufficient high rigidity and mounting strength are secured to the anchor, so that the anchor can be applied to a high torque drum brake despite being formed of a single metal plate, and In addition, a stable braking force can be secured, and the durability of the anchor can be improved.

[Brief description of the drawings]

FIG. 1 is a front view of a drum brake showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along the line III-III of FIG. 1;

FIG. 4 is a perspective view of an anchor.

FIG. 5 is a perspective view of an anchor showing a second embodiment of the present invention.

[Explanation of symbols]

1. Drum brake, 2. Back plate, 3a, 3b
... brake shoes, 3c ... web, 3e ... lining,
4 ... Actuator, 4a ... Sliding block, 4b ... Brake lever, 4c ... Adjust bolt, 5 ... Anchor,
5a: plate portion, 5b: pedestal portion, 5c: leg portion, 5d: ear portion,
5e ... thickness end face

Claims (1)

(57) [Scope of request for utility model registration] An actuator is provided between one end of a pair of brake shoes disposed opposite to a back plate, and the other end is provided with an actuator.
Respectively disposed an anchor between one of said anchor support point
In a vehicle drum brake that performs a braking action by expanding a pair of brake shoes by an actuator, the anchor is folded back at a central portion of a metal plate so that the plate portions face each other.
The two plate portions are formed to have a double plate structure, and the leg portions are respectively provided on the anti-return side end surfaces of both plate portions so that both plate portions are half of the back plate.
The legs are fixed to the back plate so as to be disposed inward and outward in the radial direction, and the leg portions are orthogonal to the end faces on the anti-return side of both plate portions.
That the side plates Atsutan surface, a vehicle drum brake, characterized in that contact against the other end of the pair of brake shoes.