JP2011149544A - Drum brake device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drum brake device allowing installation of a strut assembly while placing a brake shoe on a back plate. <P>SOLUTION: The drum brake device with a one shot type shoe clearance automatic adjusting device has a structure allowing the strut assembly 20 to be installed from a brake drum side in the axle direction. A floating restricting means is provided for restricting floating of the strut assembly 20. The floating restricting means is a shoe return spring 16. The floating restricting means restricts floating of the strut assembly 20 by abutting one side of a strut body 21 against a shoe web 11a of the brake shoe 11. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a drum brake device, and more particularly to a drum brake device including a one-shot type shoe gap automatic adjusting device.

  As shown in FIG. 10, a strut body 121 disposed between a pair of brake shoes 11, 12 disposed opposite to each other on the back plate 10, and can be rotated with respect to the strut body 121. A strut assembly 120 including a quadrant 122 pivotally supported on one side of the strut body 121 movably in the longitudinal direction is formed, and a projecting arm portion 122c (shoe engagement) provided on the quadrant 122 of the strut assembly 120 Part) is engaged with a quadrant engagement hole 11d (quadrant engagement part) provided in the shoe web of one brake shoe 11 with play, and the amount of expansion of the brake shoes 11 and 12 exceeds a predetermined value. When the quadrant 122 rotates, the gap between the brake shoes 11, 12 and the brake drum (not shown) ( Drum brake device equipped with an automatic shoe clearance adjustment apparatus that adjusts the-menu gap) automatically is widely known (Patent Document 1).

  According to this drum brake device, the strut assembly 120 is temporarily assembled between the pair of brake shoes 11 and 12 and then placed on the back plate 10, and thereafter, a known shoe hold device or shoe spring is assembled. Is going.

  Therefore, according to this drum brake device, the work of temporarily assembling the strut assembly 120 between the brake shoes 11 and 12 is complicated, and the temporary assembly state of the brake shoes 11 and 12 and the strut assembly 120 is changed. There is a problem that care must be taken when placing on the back plate 10 while maintaining, and as a whole, it takes a lot of man-hours to assemble the drum brake device.

  Further, according to this drum brake device, in order to reduce the diameter of the brake shoes 11 and 12 when the brake shoe is replaced, for example, as shown by a two-dot chain line in FIG. It is necessary to rotate the quadrant 122 in the direction of reducing the outer diameter of the brake shoes 11 and 12 (counterclockwise in FIG. 10) with a tool T such as a minus-type screwdriver inserted into the inside. There is a problem that it is difficult to rotate such a quadrant 122 in the approaching direction of the back plate 10.

JP 59-126127 A

The present invention has been made in order to solve the above-described problems. The object of the present invention is to provide a state in which a brake shoe is placed on a back plate in a drum brake device including a one-shot type shoe gap automatic adjusting device. It is an object of the present invention to provide a drum brake device in which a strut assembly can be easily assembled.
Furthermore, an object of the present invention is to provide a drum brake device that can easily perform the work of reducing the outer diameter of the brake shoe.

The present invention provides a strut body disposed between adjacent ones of a pair of opposing brake shoes, one of the strut bodies movable in the longitudinal direction of the strut body and rotatable with respect to the strut body. A strut assembly including a quadrant pivotally supported on the quadrant, and a shoe engaging portion provided in the quadrant of the strut assembly having play in a quadrant engaging portion provided in a shoe web of one brake shoe. In the drum brake device including the shoe gap automatic adjusting device that engages and the quadrant rotates when the brake shoe spread amount exceeds a predetermined value to automatically adjust the brake shoe gap. A drum brake device characterized in that the strut assembly can be assembled from the brake drum side in the axle direction.
Further, in the above drum brake device, a lift limiting means for limiting the lift of the strut assembly is provided.
In the above drum brake device, the lift limiting means is a shoe spring.
Further, in the above drum brake device, the lift limiting means limits the lift of the strut assembly by bringing one of the strut bodies into contact with the shoe web of the one brake shoe. Device.
Further, in the drum brake device described above, the drum brake device is provided with a restricting means for restricting the other lift of the strut body.

According to the present invention, since the strut assembly can be assembled from the brake drum side in the axle direction with the brake shoe placed on the back plate, the number of assembling steps of the drum brake device is greatly reduced. .
Furthermore, according to the present invention, the work of reducing the outer diameter of the brake shoe can be easily performed.

The top view of the drum brake device provided with the shoe gap automatic adjustment device concerning Example 1 of the present invention. II-II sectional view of FIG. FIG. 2A is an enlarged view of the meshing portion of the quadrant adjusting teeth and the strut body adjusting teeth in FIG. 2A. III-III sectional view of FIG. 2A Exploded assembly drawing of strut assembly Top view of drum brake device before assembly of strut assembly VV sectional view of FIG. 5A Cross-sectional view of drum brake device after assembly of strut assembly Sectional drawing of the drum brake device which concerns on the modification of Example 1 of this invention. VII-VII sectional view of FIG. A drum brake device equipped with a shoe gap automatic adjusting device according to a second embodiment of the present invention using a strut holding spring, and is an enlarged view on the right side of the strut assembly. FIG. 6 is a drum brake device including a shoe gap automatic adjusting device according to a second embodiment of the present invention, and an overall perspective view of a strut holding spring; FIG. 6 is a drum brake device equipped with an automatic shoe clearance adjusting device according to a second embodiment of the present invention using another strut holding spring, and is an enlarged view on the right side of the strut assembly. FIG. 6 is a drum brake device including a shoe gap automatic adjusting device according to a second embodiment of the present invention, and an overall perspective view of a strut holding spring; Cross-sectional view of a drum brake device provided with an automatic shoe clearance adjustment device premised on the present invention

  Embodiment 1 of the present invention will be described below with reference to FIGS.

<1> Overall Structure of Drum Brake Device FIG. 1 is a plan view of a leading / trailing type (LT type) drum brake device having a parking brake mechanism and a one-shot type shoe clearance automatic adjusting device. 2A shows a cross-sectional view thereof, FIG. 3 shows a longitudinal cross-sectional view of the strut body 21, FIG. 4 shows an exploded view of the strut assembly 20, and FIG. 5A shows a state before the strut assembly 20 is assembled. FIG. 5B shows a plan view of the drum brake device, FIG. 5B shows a cross-sectional view of the drum brake device before assembly of the strut assembly 20, and FIG. 5C shows a cross-sectional view of the drum brake device after assembly of the strut assembly 20. Indicates.

  In the drum brake device of FIG. 1, reference numeral 10 denotes a back plate fixed to a stationary part of the vehicle with a bolt or the like, and a pair of brake shoes 11 and 12 are slidably supported by known shoe hold devices 13 and 13. Yes.

  A pair of brake shoes 11 and 12 having a T-shaped cross section formed by joining shoe rims 11b and 12b to shoe webs 11a and 12a and fixing linings 11c and 12c to outer peripheral surfaces of shoe rims 11b and 12b, respectively. Ends (upper ends in FIG. 1) are respectively engaged with pistons of a wheel cylinder 14 that is a shoe expansion device for service brakes, and other ends (lower ends in FIG. 1) are respectively attached to anchors 15 fixed to the back plate 10. It is supported.

  The wheel cylinder 14 is fixed to the back plate 10 with a bolt or the like, and its piston is configured to always move in the expansion / contraction direction of one end of each brake shoe 11, 12.

  Shoe return springs 16, 17 are stretched between the pair of brake shoes 11, 12, and the brake shoes 11, 12 are urged in the diameter reducing direction.

Adjacent to the wheel cylinder 14, a strut assembly 20 constituting a shoe gap automatic adjusting device is horizontally mounted between the brake shoes 11 and 12.
As will be described later, the drum brake device according to the present invention, after assembling a pair of brake shoes 11 and 12 to the back plate 10, sandwiches the pair of brake shoes 11 and 12 on the opposite side of the back plate 10 (the brake drum). The strut assembly 20 can be assembled between the brake shoes 11 and 12 from the side on which the is assembled.

The brake lever 30, which is a shoe expansion device for a parking brake, is superposed on the shoe web 12a of the other brake shoe 12, and its base end (upper end in FIG. 1) is at one end of the shoe web 12a. The lever pin 31 is rotatably supported.
The brake lever 30 is biased in the anti-cable pulling direction (clockwise in FIG. 1) via the strut assembly 20 that receives the spring force of the shoe springs 16 and 17, and the stopper 30a abuts against the shoe rim 12b and returns to it. The position is regulated.
A brake cable (not shown) is connected to the free end (lower end in FIG. 1) of the brake lever 30.

<2> Shoe Clearance Automatic Adjustment Device As shown in FIGS. 2A and 4, the strut assembly 20 includes a plate-like strut body 21, a quadrant 22, a pin 23 fixed to the quadrant 22, and a strut body 21 and a pin 23. The quadrant spring 24 is stretched, and the strut assembly 20 and the anti-rattle spring 25 constitute an automatic shoe clearance adjusting device.

Adjustment teeth 21 a are engraved in the middle part of the strut body 21.
A quadrant 22 is rotatably supported on the right side of the strut body 21 by a pin 23 so as to be rotatable along a longitudinal plate surface of the strut body 21.

  Adjustment teeth 22b carved on the outer periphery of the fan-shaped arm portion 22a of the quadrant 22 mesh with the adjustment teeth 21a of the strut body 21 (see FIG. 2B), and a quadrant spring 24 stretched between the strut body 21 and the pin 23. Is urged in a direction to maintain the meshing of both adjusting teeth 21a and 22b.

  The relationship between the mounting load of the quadrant spring 24 and the anti-rattle spring 25 is such that the anti-rattle spring 25 becomes larger so that the quadrant spring 24 extends and the engagement teeth 21a and 22b are disengaged when the shoe clearance is automatically adjusted. It is set to.

A projecting arm portion 22c having a cam surface 22d is provided on the right side of the quadrant 22, and the projecting arm portion 22c is formed in a quadrant engaging hole 11d formed in the shoe web 11a of one brake shoe 11. The brake inner surface is loosely fitted with a predetermined gap δ, and the cam surface 22d is in contact with the brake outer surface of the quadrant engagement hole 11d.
The automatic shoe gap adjusting device automatically adjusts the shoe gap between the brake shoes 11 and 12 and the brake drum by rotating the quadrant 22 when the spread amount of the brake shoes 11 and 12 exceeds a predetermined value. .

On the left side of the strut body 21, a notch 21b and a projecting engagement arm 21c facing the notch 21b are formed.
Both the projecting arm portion 22c of the quadrant 22 and the engaging arm portion 21c of the strut body 21 protrude in the same direction, and are opposite to the back plate 10 with the pair of brake shoes 11 and 12 therebetween (the brake drum is The strut assembly 20 can be assembled from the assembly side).

A left engagement arm 21c of the strut body 21 is loosely fitted in a rectangular engagement hole 12d formed in the shoe web 12a of the other brake shoe 12 with a gap.
The reason why the engaging arm portion 21c is loosely fitted into the engaging hole 12d is to limit the movement of the strut body 21 in the direction perpendicular to the paper surface in FIG. 2A.
Note that this clearance is sufficient if the engagement arm portion 21c and the engagement hole 12d do not interfere with each other when the parking brake is operated. In other words, when the parking brake is operated, the strut assembly 20 moves to the right in the drawing, and the other brake shoe 12 moves to the left in the drawing.

  The rectangular engagement hole 12d formed in the shoe web 12a of the other brake shoe 12 can also be used in layout with the quadrant engagement hole 11d formed in the shoe web 11a of one brake shoe 11. When the brake shoes 11 and 12 are common, it is not necessary to form another hole.

<3> Lifting Limiting Unit for Strut Assembly The drum brake device according to the present invention includes lifting limiting means for limiting the lifting of the strut assembly 20 that has been assembled in a direction away from the back plate 10.
In this example, a case will be described in which the lifting restriction means causes the shoe return spring 16 to abut on a latch 26 attached to the strut body 21 and the shoe return spring 16 biases the strut assembly 20 toward the back plate 10 side. .

The latch 26 is formed by bending a rectangular steel plate or the like, and is folded so that one of the main body 26a and the main body 26a arranged parallel to one side of the strut main body 21 can be fitted to the end of the strut main body 21. The fixing part 26b formed by bending and the other part of the main body 26a are bent into a J shape, and a hooking part 26c formed so as to be hookable with a part of the shoe spring 16 is provided.
The distal end portion of the fixing portion 26b is folded back toward the main body 26a so as to be fitted to a horizontally long slit 21d formed on the side surface of the strut main body 21.

<4> Assembly work of the drum brake device According to the conventional assembly method of the drum brake device, the strut assembly is temporarily assembled between the pair of brake shoes, and the temporary assembled state of the pair of brake shoes and the strut assembly is maintained. However, it was mounted on the back plate.
On the other hand, in the present invention, the pair of brake shoes 11 and 12 are mounted on the back plate 10 and assembled, and then the strut assembly 20 is assembled. Can be assembled. Hereinafter, the assembly work of the drum brake device will be described.

  In FIG. 1, one brake shoe 11 is mounted on a back plate 10, and a brake lever 30 is preliminarily superimposed on a shoe web 12 a of the other brake shoe 12, and the brake shoe 12 that is rotatably supported by a lever pin 31 is mounted. And slidably assembled by known shoe hold devices 13 and 13.

  Shoe return springs 16 and 17 are stretched between the pair of brake shoes 11 and 12, and one end (the upper end in FIG. 1) of the pair of brake shoes 11 and 12 is engaged with the piston of the wheel cylinder 14, respectively. The other ends (the lower ends in FIG. 1) are supported by the anchors 15 fixed to the back plate 10 to complete the assembly of the pair of brake shoes 11 and 12. (See FIGS. 5A and 5B)

Next, the strut assembly 20 is assembled from the side opposite to the back plate 10 (the side on which the brake drum is assembled) across the pair of brake shoes 11 and 12. (See Figure 5C)
By assembling the strut assembly 20 between the pair of brake shoes 11, 12, the protruding arm portion 22 c on the right side of the quadrant 22 has a quadrant engagement hole 11 d formed in the shoe web 11 a of one brake shoe 11. The engagement arm portion 21c formed on the left side of the strut body 21 is inserted into the rectangular engagement hole 12d formed in the shoe web 12a of the other brake shoe 12 with a gap (see FIG. 2A).

  In the present invention, the projecting arm portion 22c of the quadrant 22 constituting the strut assembly 20 and the engaging arm portion 21c of the strut body 21 protrude in the same direction, so that the pair of brake shoes 11 and 12 are sandwiched between them. The strut assembly 20 can be assembled from the side opposite to the back plate 10 (the side on which the brake drum is assembled).

  An anti-rattle spring 25 is stretched between the strut body 21 and the other brake shoe 12.

When the assembly of the anti-rattle spring 25 is completed, the straight portion 16a of the shoe spring spring 16 is hooked to the hook portion 26c of the hook 26, and the distal end portion of the fixing portion 26b is formed on the side surface of the strut body 21. The latch 26 is hung between the strut body 21 and the shoe spring 16 by being fitted into the horizontally long slit 21d. (See Figure 3)
Since the strut assembly 20 that has been assembled is supported by the shoe spring 16 via the hook 26, the strut assembly 20 can be effectively prevented from being lifted.

  As described above, according to the present invention, since the strut assembly 20 can be assembled later with the brake shoes 11 and 12 mounted on the back plate 10, the assembly work of the drum brake device can be simplified as compared with the conventional case. Furthermore, the number of work steps required for assembling the drum brake device can be greatly reduced.

  In the above description, the strut assembly 20 in which the quadrant spring 24 is stretched is used, but the quadrant spring 24 is disposed on the side opposite to the back plate (the brake drum is assembled) with the pair of brake shoes 11 and 12 interposed therebetween. Therefore, the quadrant spring 24 can be retrofitted.

  It is also possible to retrofit only the shoe spring 16 or both the shoe springs 16 and 17. In this case, the latch 26 may be attached to the strut assembly 20 in advance.

<5> Shoe clearance automatic adjustment action The linings 11c and 12c wear, and the expansion amount of the pair of brake shoes 11 and 12 is the clearance δ between the projecting arm portion 22c of the quadrant 22 and the quadrant engagement hole 11d of the shoe web 11a. Exceeds the above, the contact state of the engagement arm portion 21c with the inner surface of the engagement hole 30b on the brake inner side is maintained. At this time, a force that acts on the quadrant 22 in the clockwise direction in FIG. 2A is generated by the force acting on the protruding arm portion 22c.

As described above, the relationship between the mounting load of the quadrant spring 24 and the anti-rattle spring 25 is set so that the quadrant spring 24 extends and the meshing of the adjusting teeth 21a and 22b is released during the automatic adjustment of the shoe clearance. Then, the quadrant 22 rotates, and the meshing state of the two adjustment teeth 21a and 22b changes.
Since the quadrant 22 rotates clockwise in FIG. 2A, the quadrant 22 does not approach the brake drum (not shown) or the hub (not shown).

When the meshing state of the adjusting teeth 21a and 22b changes, the contact point of the cam surface 22d of the protruding arm portion 22c that contacts the quadrant engagement hole 11d of the shoe web 11a is displaced by the amount of the meshing state change. The distance between the inner side of the brake outer side of the quadrant engaging hole 11d supported by the protruding arm portion 22c and the side surface of the notch portion 21b of the strut body 21 supporting the inner edge of the brake lever 30 is extended so that the shoe gap is always approximately. Kept constant.
In other words, the substantially effective length of the strut assembly 20 is extended to close the shoe gap between the brake shoes 11 and 12 and the brake drum (not shown), so that the shoe gap is always kept substantially constant.
When the linings 11c and 12c are normally worn (when worn normally), the meshing state of the adjusting teeth 21a and 22b changes by one tooth.

  Further, when the parking brake is operated, the cam surface 22d of the projecting arm portion 22c of the quadrant 22 contacts the inner surface of the brake outer side of the quadrant engaging hole 11d formed in the shoe web 11a of one brake shoe 11. This is maintained, and the strut assembly 20 only moves to the right in the drawing together with the one brake shoe 11, so that there is no effect on the shoe gap automatic adjustment action.

<6> Action to prevent strut assembly from being lifted The drum brake device is provided with a strut assembly by a vibration caused by running vibration, gravity or the like, or a moment caused by the anti-rattle spring 25 acts on the strut assembly 20 due to layout restrictions. There is a concern that the solid 20 may be lifted from the pair of brake shoes 11 and 12.
In this example, the straight portion 16a of the shoe spring 16 is restrained from lifting off the strut assembly 20 in the direction away from the back plate 10 via the latch 26 attached to the strut body 21, thereby preventing the strut assembly 20 from coming off. Can be prevented.
Therefore, the projecting arm portion 22c of the quadrant 22 is maintained loosely fitted in the quadrant engagement hole 11d formed in the shoe web 11a of one brake shoe 11, and is formed on the left side of the strut body 21. The engagement arm portion 21c can also maintain a loosely fitted state in a rectangular engagement hole 12d formed in the shoe web 12a of the other brake shoe 12.

<7> Brake shoe diameter reduction operation According to the drum brake device of the present invention, the quadrant 22 of the strut assembly 20 is disposed in the opposite direction with respect to the back plate 10 as compared with the conventional case. The direction of rotation in the radial direction is the reverse of the conventional one.
Therefore, by pushing the quadrant 22 with a tool such as a screwdriver inserted into the drum brake device from the outside of the back plate 10 in order to reduce the diameter of the brake shoes 11, 12, the diameter of the brake shoes 11, 12 is reduced. Therefore, the diameter reduction work of the brake shoes 11 and 12 is simplified.
Further, as described above, the drum brake device is provided with means for restricting the lifting of the strut assembly 20, so that there is no fear that the strut assembly 20 is detached from the brake shoes 11, 12 when the diameter of the brake shoes 11, 12 is reduced. .

[Modification of Example 1]

  Hereinafter, modifications and other embodiments will be described. In the description, the same portions as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

FIGS. 6 and 7 show a modification of the first embodiment in which the lifting limiting means of the strut assembly 20 presses the latching portion 21e formed integrally with the strut body 21 by the coil portion 16b of the shoe spring 16.
This example shows a case where the latching portion 21e is formed by folding a part of the plate piece of the strut body 21 so that it can be latched with the coil portion 16b formed at the center of the shoe spring 16. A part of the plate 21 may be cut and raised to form a latching portion (not shown).

  Since the configuration of the strut assembly 20 other than the lifting restriction means and the shoe gap automatic adjusting action are the same as those of the first embodiment, the description thereof will be omitted.

  With reference to FIGS. 8A and 8B and FIGS. 9A and 9B, a second embodiment in which the lifting limiting means of the strut assembly 20 is a component other than the shoe spring 16 will be described.

  FIG. 8A is a view showing the lifting limiting means of the strut assembly 20 that limits the lifting of one of the strut bodies 21 that is the pivot side of the quadrant 22 by the strut holding spring 27, and FIG. 8B is the entire strut holding spring 27. A perspective view is shown.

The strut holding spring 27 is made of an elastic spring body formed by bending a single wire spring or leaf spring into a substantially U shape, and has a holding portion 27a bent at the center so that the right side of the strut body 21 can be held. Two linear portions 27b extending from the sandwiching portion 27a, and a hook portion 27c formed by folding the end portions of the linear portions 27b so as to protrude at right angles toward the outside (in the direction away from each other). Have.
The end portion side of the sandwiching portion 27 a is formed in a tapered shape so that it can be easily inserted into the elongated hole 11 e formed in the shoe web 11 a of one brake shoe 11.

The assembling operation for assembling the strut assembly 20 from the side opposite to the back plate 10 (the side where the brake drum is assembled) across the pair of brake shoes 11 and 12 is the same as in the first embodiment.
As the strut assembly 20 is assembled, the right protruding arm portion 22 c of the quadrant 22 is loosely fitted into the quadrant engaging hole 11 d formed in the shoe web 11 a of one brake shoe 11.
When the strut holding spring 27 is pushed across the right side of the strut body 21 in this state, the latching portion 27c of the strut holding spring 27 is inserted through the elongated hole 11e of one brake shoe 11 and hooked on the back surface of the shoe web 11a. Stopped.
The strut holding spring 27 is swingable with respect to the shoe web 11a, and allows the strut body 21 to slide with respect to the shoe web 11a.

  FIG. 9A is a view showing the lift limiting means of the strut assembly 20 for limiting the other lift of the strut body 21 by the strut holding spring 28, and FIG. 9B is an overall perspective view of the strut holding spring 28. .

The strut holding spring 28 is an elastic spring body attached to the left side of the strut body 21, a holding part 28 a that can be attached to the edge of the strut body 21, a right angle bend from one end of the holding part 28 a, A latching portion 28b formed in a V shape by folding the intermediate portion toward the clamping portion 28a.
The sandwiching portion 28a having a U-shape is fixed to the strut body 21 by known positioning means such as caulking with a separate pin.
The distal end portion of the latching portion 28b having elasticity protrudes until reaching the open side space of the notch portion 21b formed on the left side of the strut body 21.
The length of the latching portion 28b is set to a length that can limit the lifting of the strut main body 21 when the tip end is pressed against the back surface of the brake lever 30.

The strut holding spring 28 is fixed to the strut body 21 in advance, and the strut assembly 20 is only assembled from the side opposite to the back plate 10 (the side on which the brake drum is assembled) across the pair of brake shoes 11 and 12. The lifting of the strut body 21 can be limited by supporting the brake lever 30 by the operation of the above. That is, as the strut assembly 20 is assembled, the latch projecting into the open side space of the notch 21b of the strut body 21 The portion 28b abuts against the inner edge of the brake lever 30 and is compressed and deformed. When the tip of the latching portion 28b exceeds the brake lever 30, the tip of the latching portion 28b is restored by the spring force and is stretched to the back surface of the brake lever 30. put out.
Accordingly, the left side of the strut body 21 is supported by the brake lever 30 via the strut holding spring 28, so that the strut body 21 is restricted from rising.

10 Back plates 11, 12 Brake shoes 11a, 12a Shoe webs 11b, 12b Shoe rims 11c, 12c Lining 11d Quadrant engagement holes 13 Shoe hold device 14 Wheel cylinder 15 Anchors 16, 17 Shoe lantern spring 20 Strut assembly 21 Strut body 21a ( Adjustable teeth 21b (of the strut body) Notch portion 21c (of the strut body) Engaging arm portion 21d (strut body) slit 21e (strut body) latching portion 22 quadrant 22a (quadrant) fan-shaped arm 22b (quadrant) adjusting teeth 22c (quadrant) projecting arm 23 pin 24 quadrant spring 25 anti-rattle spring 26 latch 26a (hanger) body 26b (hanger) Fixing part 26c Hooking part 27 (for the strut holding spring) 27 Strut holding spring 27a (Strut holding spring) Holding part 27b (Strut holding spring) Linear part 27c (Strut holding spring) Hatching part 28 Strut holding spring 28a ( Clamping portion 28b (of strut holding spring) Holding portion 30 Brake lever 30a (Brake lever) Stopper 30b (Brake lever) engagement hole 31 Lever pin

Claims (5)

A strut body disposed between adjacent portions of a pair of opposing brake shoes, and is pivotable with respect to the strut body and is pivotally supported on one of the strut bodies movably in the longitudinal direction of the strut body. A strut assembly including a quadrant is formed, and a shoe engaging portion provided on the quadrant of the strut assembly is engaged with a quadrant engaging portion provided on a shoe web of one brake shoe with play. In the drum brake device provided with the shoe gap automatic adjusting device for automatically adjusting the gap of the brake shoe by rotating the quadrant when the expansion amount of the brake shoe exceeds a predetermined value,
The strut assembly is structured to be assembled from the brake drum side in the axle direction,
Drum brake device.   2. The drum brake device according to claim 1, further comprising a lift limiting means for limiting the lift of the strut assembly.   3. The drum brake device according to claim 2, wherein the lifting restriction means is a shoe spring.   The drum brake device according to claim 2, wherein the lift limiting means limits the lift of the strut assembly by bringing one of the strut bodies into contact with a shoe web of the one brake shoe. Drum brake device.   5. The drum brake device according to claim 4, further comprising a restricting means for restricting the other lift of the strut body.

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