JP2018004028A - Shoe hold device of drum brake - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance transportation efficiency by eliminating the tangling of a shoe hold spring and a shoe hold pin, and to enhance the workability of a shoe hold device.SOLUTION: A second arm piece 32 of a U-shaped shoe hold spring 30 which is arranged on an upper face at a side opposite to a back plate 10 of a shoe web 11a of a brake shoe 11 placed on the back plate 10 has a temporary locking part 30A which can temporarily lock the shoe hold pin 40, and a main locking part 30B which locks the shoe hold pin 40. The shoe hold pin 40 has a pair of first locking parts 41, 41 which penetrate a pin locking hole 10a of the back plate 10 from the shoe web 11a side, and can be locked thereto, and a second locking part 42 which can be locked to the second arm piece 32 of the shoe hold spring 30.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a drum brake shoe hold device that slidably and elastically holds a brake shoe on a back plate by inserting a shoe hold pin from the opposite side of the back plate across a shoe web.

  In the drum brake, a brake shoe that frictionally engages the sliding surface of the brake drum is elastically held on the back plate by a shoe hold device.

Generally, a shoe hold device comprising a shoe hold spring in which a belt-like leaf spring is bent into a U-shape, a shoe hold pin having a head and a flat latching portion formed at both ends of the pin shaft and having a diameter larger than that of the pin shaft. Is widely known (Patent Document 1).
Assembling operation of a general shoe hold device is to place the brake shoe on the back plate, insert the shoe hold pin from the back plate side, and insert it into the pin insertion hole drilled in the shoe web of the brake shoe, A shoe hold spring through-hole is fitted into the shaft of the shoe hold pin that protrudes on the opposite side of the shoe web back plate while holding the head and the back plate. Place one end, and use a special tool to push the other end of the shoe hold spring toward the shoe web and elastically deform the U-shaped spring. The flat latching part of the shoe hold pin is latched to the latching part at the other end of the shoe hold spring. So as to obtain, and the shoe-hold pin performs assembled with 90 ° rotation operation.

It has been pointed out that such a general shoe hold device is troublesome in assembling a shoe hold pin.
In response to this indication, there has been proposed a shoe hold device in which a shoe hold pin is integrally formed on a part of a spring body so that assembly can be performed from the opposite side (shoe web side) of the back plate.
Patent Document 2 discloses a shoe hold device in which a central portion of a U-shaped spring body is cut and raised to integrally form a strip-like (thin plate-like) shoe hold pin.
The shoe hold pin of this shoe hold device has its tip end folded back to a size larger than the width of the through hole to form a pair of latching projections, and the shoe hold pin body following the pair of latching projections By being elastically deformed, the latching protrusions can be latched through the through holes of the back plate.
When removing the shoe hold device, the hook with the back plate can be released by elastically deforming the shoe hold pin main body.

Japanese Utility Model Publication No. 62-77334 (FIGS. 5 and 6) JP 2007-303537 A (FIGS. 2 and 4)

The shoe hold device described in Patent Document 2 has the following problems.
(1) Since the U-shaped spring body has a complicated shape with a strip-shaped shoe hold pin integrated, it is very difficult to manufacture the pin integrated shoe hold pin, and the manufacturing cost is also low. There is a problem that it is bulky.
(2) Since the pin-integrated shoe hold spring has a strip-shaped shoe hold pin projecting from the side of the U-shaped spring body, the shoe hold spring can be connected to each other when the shoe hold device is transported from the production location to the drum brake assembly location. Easy to entangle. For this reason, a large number of shoe hold devices cannot be packed in a box, and transportation efficiency is low.
(3) The pin holding shoe hold spring is not only time consuming and troublesome to separate the tangled shoe hold device when used at the place of installation, but also the shoe hold pin may be deformed when separated. There is.
(4) In order to eliminate the entanglement of the shoe hold device, a method of transporting the pin-integrated shoe hold spring by a returnable box having a structure that can be aligned can be considered, but there is a problem that the number of man-hours to be aligned increases.

The present invention has been made in view of the above-described points, and an object of the present invention is to provide a shoe brake device for a drum brake that improves the transport efficiency by eliminating the entanglement between a U-shaped shoe hold spring and a shoe hold pin. It is to provide.
A further object of the present invention is to provide a drum brake shoe hold device capable of improving the workability of assembly and disassembly of the shoe hold device.

The present invention provides a first arm piece disposed on the upper surface of the shoe web of the brake shoe placed on the back plate opposite to the back plate, a second arm piece formed opposite to the first arm piece, And a shoe hold spring comprising a curved connecting portion connecting the first arm piece and the second arm piece, and a shoe hold spring formed separately from the shoe hold spring, one of which is hooked on the second arm piece A drum brake shoe hold device, the other of which has a shoe hold pin that elastically holds the shoe hold spring, the other arm piece of the shoe hold spring being hooked to a pin latch hole of a back plate. A temporary latching portion capable of temporarily latching the shoe hold pin on the tip side thereof, and a main latching portion latching the shoe hold pin closer to the connecting portion side than the temporary latching portion; The shoe hold pin can be hooked to a pin hooking hole of the back plate from the shoe web side and hooked to the second arm of the shoe hold spring. A second latching portion.
In another embodiment of the present invention, the second hooking portion of the shoe hold pin is hooked on the temporary hooking portion of the second arm piece, and the shoe hold spring is elastically deformed, thereby When shifting from the state in which the stop portion is hooked to the pin latch hole of the back plate to the state in which the second hook portion of the shoe hold pin is hooked to the main hook portion of the second arm piece, A guide portion for guiding the shoe hold pin is provided on the second arm piece of the shoe hold spring.
In another embodiment of the present invention, the temporary latching portion, the guide portion, and the permanent latching portion are formed symmetrically on both sides of the longitudinal center line of the second arm piece.
In another embodiment of the present invention, the temporary latching portion, the guide portion, and the regular latching portion are slits having continuity.
In another embodiment of the present invention, the shoe hold pin is a pin obtained by bending a spring material into a bifurcated shape, and has a pair of connecting legs that can be closed and opened, and the pair of connecting legs A second hooking portion that can be hooked and pressed on the second arm piece of the shoe hold spring is formed on one of the two, and a pair of second hooks that can be hooked on the side surface of the back plate on the other of the connecting legs. A stop is formed.
In another embodiment of the present invention, the pair of connecting legs of the shoe hold pin are offset so that they do not interfere with each other when the legs are closed.
In another embodiment of the present invention, the second hooking portion includes two ear portions formed continuously with the connecting leg, and a pressing portion formed continuously between the two ear portions. And the second arm piece can be pressed via the pressing portion.

Since the shoe hold device according to the present invention is composed of a U-shaped shoe hold spring and a separate shoe hold pin having a substantially bifurcated shape, the shoe hold device and the shoe hold pin are entangled and the shoe hold device is transported efficiently. Can be increased.
In addition, the work at the assembly place can be made efficient.
Furthermore, since the present invention can move the shoe hold pin by utilizing the principle of lever, the workability of assembling and disassembling the shoe hold device is remarkably improved.

Sectional drawing of the shoe hold apparatus of the drum brake concerning Example 1 of this invention. The disassembled perspective view which shows the structure of the shoe hold apparatus concerning Example 1 of this invention. The top view of the 2nd arm piece which comprises the shoe hold spring for demonstrating the displacement of a pair of connecting leg of a shoe hold pin Longitudinal sectional view of a shoe hold device comprising a shoe hold pin before and after rotating the shoe hold pin and a compressed shoe hold spring VV sectional view of FIG. It is explanatory drawing of the assembly | attachment operation | work of the shoe hold apparatus concerning Example 1, Comprising: (A) describes the process of mounting the 1st arm piece of a shoe hold spring on the side surface of a shoe web, and aligning a pin insertion hole. FIG. 5B is a cross-sectional view of the assembling portion for the purpose of carrying out the process, FIG. 5B is a cross-sectional view of the assembling portion for explaining a process of passing the pair of connecting legs of the shoe hold pin through the shoe hold spring and the shoe web, and FIG. Sectional drawing of the assembly | attachment part for demonstrating the process until the front-end | tip of the shoe hold pin pushed in elastically deforming the hold spring penetrates a pin latch hole, (D) is a pair of 1st latch part. Sectional drawing of the assembly | attachment part which shows the temporary latching state in which the 1st latching part of the front-end | tip contact | abutted to the side surface of the backplate The disassembled perspective view which shows the structure of the shoe hold apparatus concerning Example 2. FIG. Sectional view of the assembly where the lower half of the pair of connecting legs of the shoe hold pin is closed It is sectional drawing of the lower half part of a pair of connecting leg at the time of the closed leg in Example 1 and Example 2, Comprising: (A) is a pair of connecting leg in Example 1. Sectional drawing of lower half, (B) is IX-IX sectional view of FIG. Longitudinal sectional view of the shoe hold device with the shoe hold pin attached to the shoe hold spring in the normal position

  A drum brake shoe hold device according to the present invention will be described below with reference to the drawings.

A first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a sectional view of a shoe hold device in which a brake shoe is elastically held on a back plate, and FIG. 2 is an exploded perspective view of the shoe hold device.

  Referring to FIGS. 1 and 2, the shoe hold device 20 according to the first embodiment includes a shoe hold spring 30 and a shoe hold pin 40, and the brake shoe 11 is placed on a back plate 10 that is a stationary member. It is slidable and elastically held.

The shoe hold spring 30 is formed by bending a single spring plate material into a substantially U shape, and is formed on the upper surface of the shoe web 11a of the brake shoe 11 placed on the back plate 10 on the side opposite to the back plate 10. The first arm piece 31 to be disposed, the connecting portion 33 that is connected to the first arm piece 31 and curved in an arc shape, and the first arm piece 31 that is connected to the connecting portion 33. And a second arm piece 32 formed opposite to each other.
A pin insertion hole 31 a into which the shoe hold pin 40 can be inserted is formed in the center of the first arm piece 31.

The second arm piece 32 is engaged with a pair of temporary latching portions 30A and 30A capable of temporarily locking the shoe hold pin 40, and the shoe hold pin 40 closer to the connecting portion 33 than the temporary latching portion 30A. A pair of main latching portions 30B and 30B for stopping and positioning are formed, and the pair of guide portions 30C and 30C are connected in communication between the temporary latching portion 30A and the main latching portion 30B.
The temporary latching portion 30A, the guide portion 30C, and the regular latching portion 30B are formed as continuous slits in which the second arm pieces 32 are cut out.
The pair of temporary hooks 30A, 30A, the pair of guides 30C, 30C, and the pair of main hooks 30B, 30B are formed symmetrically with respect to the center line 32a of the second arm piece 32, respectively. A neck portion 32b is formed between the left slit and the right slit.

The temporary latching portion 30 </ b> A is a slit for temporarily latching and positioning the shoe hold pin 40. The arm piece 32 is cut out toward the center line 32a.
The guide portion 30C is a slit that connects the temporary hook portion 30A and the main hook portion 30B, and a chamfered portion is formed in the guide portion 30C where the temporary hook portion 30A and the guide portion 30C are in contact with each other.
In other words, when the shoe hold pin 40 is rotated from the temporary hooking portion 30A toward the main hooking portion 30B, the pair of connecting legs 43, 43 move along the chamfered portions of the guide portions 30C, 30C. However, the leg is closed, and a portion parallel to the center line 30a of the guide portions 30C and 30C can be passed while maintaining a certain closed leg state.
The main hooking portion 30B is a slit for hooking and positioning the shoe hold pin 40 at the main hooking position, and is formed from the center line 32a side of the second arm piece 32 toward both side portions 32d. The slit end is closed.

  In this example, the temporary latching portion 30A, the guide portion 30C, and the regular latching portion 30B are shown in a substantially U-shaped form, but the slit opening shape is not limited to the illustrated form, and to the temporary latching part 30A. In the middle of rotating the introduced shoe hold pin 40 (sliding movement of the second hooking portion 42 to the main hooking portion 30B), the pair of connecting legs 43 and 43 can be forcibly closed, and the hooking pin 30B Any slit shape may be used as long as the shoe hold pin 40 can be opened and positioned at the position, and the slit end of the temporary hook 30A may be closed.

The shoe hold pin 40 is a connecting pin obtained by bending a single bar-shaped spring material into a bifurcated shape. The shoe hold pin 40 is a pair of first latching portions 41 and 41 that are latched on the pin latching hole 10a of the back plate 10, and a shoe. A second hooking portion 42 to be hooked on the second arm piece 32 of the hold spring 40, and a pair of parallel connecting legs 43 that integrally connect the first hooking portion 41 and the second hooking portion 4; 43.
The shoe hold pin 40 is centered on the pivot position where the pair of first hook portions 41 and 41 are hooked on the surface of the back plate 10 opposite to the brake shoe 11 through the pin hook hole 10a. The temporary latching portion 30A formed on the second arm piece 32 of the shoe hold spring 30 can be moved between the temporary latching portion 30B.

The lower half of the pair of connecting legs 43, 43 are parallel to each other with a certain interval, and the pair of first hooks 41, 41 are bent by outwardly bending the vicinity of the lower ends (free ends) of the connecting legs 43. The upper half of the pair of connecting legs 43, 43 is bent in an inverted C shape, and the upper part thereof is continuous with the ears 44, 44 of the second hook 42.
The overhanging length of the pair of first hooks 41 and 41 and the inner diameter of the pin hooking hole 10a of the back plate 10 are such that when the pair of connecting legs 43 and 43 are forcibly closed, the pair of first hooks 41, 41 can penetrate the pin latching hole 10a, and when the pair of connecting legs 43, 43 are opened after the penetration, the pair of first latching portions 41, 41 are opposite to the brake shoes of the back plate 10. The dimensions are such that they can be hooked to the side surface.

The second hooking portion 42 formed continuously with the connecting legs 43, 43 so as to connect the pair of connecting legs 43, 43 has two ear parts 44, 44 having an inverted U shape, and these ears. The press part 45 which connects between the parts 44 and 44 in U shape is comprised, and the whole is bent into the wave shape (substantially M shape).
The shoe hold pin 40 is applied with an external force to the pair of connecting legs 43, 43, so that the pair of connecting legs 43, 43 closes elastically around the pressing portion 45, and opens when the external force is removed.
The pair of connecting legs 43, 43 can be inserted into the shoe hold pin 40 across the neck portion 32b of the shoe hold spring 30, and the insertion of the shoe hold pin 40 is restricted by the pressing portion 45 coming into contact with the neck portion 32b. The
The entire length of the pair of connecting legs 43, 43 abuts the pin hooking hole 10 a formed in the back plate 10 with the pair of first hooking portions 41, 41 of the shoe hold pin 40 inserted into the shoe hold spring 30. Before, the pressing portion 45 of the shoe hold pin 40 comes into contact with the neck portion 32b of the shoe hold spring 30 so that the shoe hold spring 30 can be elastically deformed (compressed).

In the first embodiment, the U-shaped shoe hold spring 30 and the shoe hold pin 40 are separate bodies, and each has a simple shape that can be easily manufactured, and thus can be manufactured at low cost.
Further, since the separate shoe hold spring 30 and shoe hold pin 40 constituting the shoe hold device 20 are not easily entangled even if they are packed in large amounts with the same kind of parts, the transport efficiency of the shoe hold device 20 is increased and the work at the assembly place is performed. Efficiency.

Next, a temporary assembly method of the shoe hold device 20 will be described with reference to FIGS.
The first arm piece 31 of the shoe hold spring 30 is placed on the side surface of the shoe web 11a of the brake shoe 11, and the first arm piece 31 and the pin insertion holes 31a and 11d formed in the shoe web 11a are aligned (FIG. 6). (A)).
Next, the second latching portion 42 is picked with a finger, and the pair of connecting legs 43, 43 of the shoe hold pin 40 are connected to the pair of temporary latching portions 30A, 30A provided on the second arm piece 32 of the shoe hold spring 30. The neck 32b can be straddled while being inserted.
In this state, the pair of connecting legs 43 and 43 are inserted into the two pin insertion holes 31a and 11d in a state where the shoe hold pin 40 is inserted and the parallelism is maintained. (Fig. 6 (B))

  When the shoe hold pin 40 advances straight, the pressing portion 45 of the shoe hold pin 40 comes into contact with the neck portion 32b of the shoe hold spring 30. When the shoe hold pin 40 is pushed further against the spring force, the second arm piece 32 of the shoe hold spring 30 is first. Elastic deformation is started so as to approach the arm piece 31.

When the shoe hold pin 40 is further pushed in while elastically deforming the shoe hold spring 30, the tip of the shoe hold pin 40 comes into contact with the hole side of the pin hooking hole 10 a, and the taper angle of the first hooking portion 41 facing outward is reached. Along the pin retaining hole 10a.
The pair of connecting legs 43, 43 are closed to a position where the pair of first engaging portions 41, 41 can pass through the pin engaging hole 10a (FIG. 6C).
When the free ends of the pair of first hooking portions 41, 41 projecting through the pin hooking hole 10a, the pair of connecting legs 43, 43 are opened by the elastic restoring force, and the pair of first hooking portions 41, 41, The free end of 41 abuts against the side surface of the back plate 10 to prevent the shoe hold pin 40 from coming out (FIG. 6D).
In this example, a part of the pair of connecting legs 43, 43 is brought into contact with the pin insertion hole 31a to restrict the open legs of the connecting legs 43, 43 to a certain range, but the restriction target is the pin insertion hole 31a. Alternatively, the opening of the connecting legs 43, 43 may be regulated by contacting the inner surface of the pin retaining hole 10a provided in the back plate 10.

  When the finger is released from the shoe hold pin 40, the tip of the pair of first latching portions 41, 41 inserted into the pin latching hole 10 a by the elastic restoring force of the shoe hold spring 30 is the brake shoe 11 of the back plate 10. The pressing portion 45 of the second hooking portion 42 is elastically contacted with the neck portion 32b of the shoe hold spring 30 and the compressed state of the shoe hold spring 30 is maintained.

In this way, the pair of first latching portions 41 and 41 of the shoe hold pin 40 are latched to the pin latching hole 10a of the back plate 10 by a simple operation of simply pinching and inserting the shoe hold pin 40 with a finger. Therefore, it is not necessary to rotate the shoe hold pin 40 as in the prior art.
Further, in inserting the shoe hold pin 40, the pair of connecting legs 43, 43 are supported by the slit-like temporary latching portions 30A, 30A provided in the second arm piece 32 of the shoe hold spring 30, so that the wobble does not wobble. The shoe hold pin 40 can be inserted while maintaining a stable posture.
In this way, in the temporarily latched state of the shoe hold device 20, the spring force of the shoe hold spring 30 compressed by the shoe hold pin 40 latched on the side surface of the back plate 10 is held. Thus, the brake shoe 11 can be elastically held.

  Next, referring to FIGS. 3 to 5, a method for assembling the shoe hold device 20 in the normal position by moving the shoe hold pin 40 from the tip 32 c side toward the connecting portion 33 side with respect to the shoe hold spring 30. Will be described.

FIG. 3 shows the second arm piece 32 showing the positional relationship between the pair of connecting legs 43, 43 of the shoe hold pin 40 and the temporary latching portion 30A, the guide portion 30C, and the permanent latching portion 30B provided in the shoe hold spring 30. FIG.
FIG. 4 is a longitudinal sectional view of a shoe hold device 20 including a shoe hold pin 40 before and after rotating the shoe hold pin and a compressed shoe hold spring 30.
In FIG. 4, the shoe hold pin 40 is shown in a simplified manner for convenience. The hook point between the pair of first hook portions 41, 41 and the back plate 10 is P ₁ , and the shoe hold pin 40 is slid before sliding. the hooking point of the second engaging portion 42 of the shoe-hold pin 40 (pressing portion 45) the second arm 32 of the shoe-hold spring 30 (neck 32 b) and _{P 2,} the shoe after sliding the shoe-hold pin 40 It shows the latching point between the second hook portion 42 of the hold pin 40 the second arm 32 (neck 32 b) of (pressing portion 45) and the shoe-hold spring 30 as _{P 3.}

In the temporary hooking state of the shoe-hold apparatus 20, the first hook portion 41, 41 of the pair of shoe-hold pin 40 locks multiplying the back plate 10 through the Kaketometen P _1, the second hook portion 42 It is hooked to the second arm 32 of the shoe-hold spring 30 via the Kaketometen P _2.
In this state, when the second hooking portion 42 of the shoe hold pin 40 located at the temporary hooking portion 30A of the shoe hold spring 30 is moved to the main hooking portion 30B side, the pair of ear portions 44, 44 slide. The pair of connecting legs 43 and 43 are forcibly biased in the closing leg direction when passing through the guide parts 30C and 30C, but the first latching parts 41 and 41 are in a dimensional relationship that does not disengage from the pin latching hole 10a. It is set.

When the position of the main latching portion 30B is reached via the guide portion 30C, the pair of connecting legs 43, 43 are opened by the elastic restoring force, and are accommodated and positioned in the slits of the corresponding main latching portions 30B, 30B. The
Accordingly, the second latching portion 42 of the shoe hold pin 40 is in any direction unless the externally applied force closes the pair of connecting legs 43 and 43 to release the latching state with the main latching portions 30B and 30B. Slide movement toward is restricted.

Radial distance from the latching point P ₁ as a fulcrum at the time of rotating the shoe-hold pin 40 to the hooking point P _2, P ₃ serving as a working point in the temporary hooking state and HonKake stopped state does not change.
Since the second arm piece 32 in the temporarily hooked state is elastically deformed beyond the parallel state with respect to the first arm piece 31, the position of the action point on the second arm piece 32 is the position of the second arm piece 32. by displacing the locking point P ₂ position of the tip 32c toward the connecting portion 33 side of the engaging point P _3, the elastic force of the shoe-hold spring 30 is increased.
Accordingly, the holding force of the brake shoe 20 against the back plate 10 is also increased.
As described above, when the latching position of the second latching portion 42 of the shoehold pin 40 with respect to the shoehold spring 30 is displaced from the temporary latching portion 30A to the permanent latching portion 30B, the shoe hold structure becomes the normal position. .

When disassembly of the shoe hold device 20 is necessary due to replacement of the brake shoe 11 or the like, the work reverse to the above assembly process may be performed.
First, in a state in which the second arm piece 32 of the shoe hold spring 30 is pushed down with a finger, the pair of connecting legs 43, 43 are forcibly closed so that the pair of connecting legs 43, 43 by the main locking portions 30B, 30B Cancel positioning.
Next, the second latching portion 42 of the shoe hold pin 40 is moved from the connecting portion 33 side toward the tip 32c side with respect to the shoe hold spring 30 to relieve the tightening force of the shoe hold spring 30.
Finally, the connecting legs 43 and 43 are forcibly closed, and the pair of first latching portions 41 and 41 are removed from the pin latching holes 10a of the back plate 10, thereby removing the shoe hold pin 40 and the shoe hold spring 30. The brake shoe 11 can be removed.

In the first embodiment, the shoe hold device 20 is assembled only by rotating the shoe hold pin 40 after inserting the shoe hold pin 40 from the opposite side (the shoe web 11a side) of the back plate 10. Since attachment can be performed in a short time with a simple operation, workability is better than that of a conventional shoe hold device in which a shoe hold spring and a shoe hold pin are integrated.
Further, in the first embodiment, the shoe hold pin 40 can be rotated using the principle of the lever, so that the shoe hold pin 40 can be rotated with a small force, and the shoe hold device 20 having a high elastic force can be assembled.

  Other embodiments will be described below. In the description, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

A shoe hold device 20 according to the second embodiment will be described with reference to FIGS.
FIG. 7 shows a perspective view of the shoe hold device 20, and FIG. 8 pushes the shoe hold pin 40 while elastically deforming the shoe hold spring 30, so that the lower half of the pair of first hook portions 41, 41 of the shoe hold pin 40. 9 shows a cross-sectional view of the shoe hold device 20 when the leg is closed to a position where it can pass through the pin retaining hole 10a, and FIG. 9 shows a pair of connecting legs 43, 43 when the legs are closed in the first embodiment and the second embodiment. FIG. 10 is a cross-sectional view of the lower half of the pair of connecting legs 43 and 43 showing the mutual relationship. FIG. 10 shows a temporary latching position of the second latching portion 42 of the shoe hold pin 40 with respect to the shoe hold spring 30. The longitudinal cross-sectional view of the shoe hold apparatus 20 displaced from the part 30A to the main latching part 30B and assembled in the normal position is shown.

Referring to FIG. 7, the shoe hold device 20 according to the second embodiment intersects when a shoe hold spring 30 obtained by bending a belt-like leaf spring into a U shape and a pair of connecting legs 43 and 43 are closed. And a shoe hold pin 40 configured as described above.
The configuration and operation of the shoe hold spring 30 are the same as those in the first embodiment.
The basic configuration of the shoe hold pin 40 in the second embodiment is the same as that in the first embodiment. It is formed by offsetting.
In the second embodiment, the pin latching hole 10a opened in the back plate 10 is shown in a rectangular shape, but the pin latching hole 10a may be circular, elliptical, or the like.

The assembling method and the disassembling method of the shoe hold device 20 in the second embodiment are the same as those in the first embodiment.
In the second embodiment, when the shoe hold pin 40 is inserted and inserted into the pin retaining hole 10a of the back plate 10, the free ends of the connecting legs 43 and 43 forming the first retaining portion 41 interfere with each other. The pair of connecting legs 43, 43 can be closed without being closed.
FIG. 9A shows a cross-sectional view of the lower half of the pair of connecting legs 43, 43 showing the mutual relationship between the pair of connecting legs 43, 43 when the legs are closed in Example 1, and FIG. FIG. 4 shows a cross-sectional view of the lower half of the pair of connecting legs 43, 43 showing the mutual relationship between the connecting legs 43, 43 when the legs are closed according to the second embodiment. Fig (A), are common ChoIzuruhaba _{L 1} of the first hook portion 41 in (B).
In the shoe hold pin 40 according to the first embodiment in which the lower half portions of the pair of connecting legs 43 and 43 are formed in parallel to each other, the pair of connecting legs 43 and 43 interfere with each other when inserted into the pin hooking hole 10a. the total width _{L 2} of the pair of first hook portion 41 and 41, while twice the overhang width _{L 1} of the first hook portion 41, bending the lower half of the pair of connecting legs 43, 43 In the shoe hold pin 40 according to the second embodiment formed in a non-parallel manner, the pair of connecting legs 43 and 43 do not interfere when inserted into the pin retaining hole 10a. , 41 total width _{L 2} is, requires a smaller size than twice the protruding width _{L 1} of the first hook portion 41.
Total width L ₂ of the pair of first latching portions 41 of the second embodiment can be reduced minimum to overhang width L ₁ of the first hook portion 41.

In addition to the same advantages as the first embodiment described above are obtained in this second embodiment, since the total width L ₂ of the pair of first latching portions 41 can be made smaller than in Example 1, the shoe-hold pin 40 Can be smoothly inserted into the pin retaining hole 10a of the back plate 10, and the pin retaining hole 10a provided in the back plate 10 can be made smaller, so that the cross section of the back plate 10 can be reduced. .

DESCRIPTION OF SYMBOLS 10 Back plate 10a Pin latch hole 11, 11 Brake shoe 11a Shoe web 11d Pin insertion hole 20 Shoe hold device 30 Shoe hold spring 30A Temporary latch part 30B Main latch part 30C Guide part 31 1st arm piece 31a Pin insertion hole 32 Second arm piece 32a Second arm piece center line 32b Second arm piece neck part 32c Second arm piece tip 32d Second arm piece side part 40 Shoe hold pin 41 First hook part 42 Second hook part Part 43 connecting leg 44 ear 45 pressing part

Claims (7)

A first arm piece disposed on an upper surface of the shoe web of the brake shoe placed on the back plate opposite to the back plate; a second arm piece formed opposite to the first arm piece; A shoe hold spring comprising a curved connecting portion connecting one arm piece and the second arm piece, and formed separately from the shoe hold spring, one of which is hooked on the second arm piece and the other is a back. A drum brake shoe hold device comprising a shoe hold pin that is hooked into a pin latch hole of a plate and elastically holds the shoe hold spring,
The second arm piece of the shoe hold spring has a temporary latching portion capable of temporarily latching the shoe hold pin on the tip side thereof, and a shoe hold pin latched on the connecting portion side of the temporary latching portion. And a main latch portion to
The shoe hold pin includes a first hook portion that can be hooked by being inserted into a pin hook hole of the back plate from the shoe web side, and a second hook portion that can be hooked on a second arm of the shoe hold spring. It has a stop part,
Drum brake shoe hold device.   The second hooking portion of the shoe hold pin is hooked to the temporary hooking portion of the second arm piece, the shoe hold spring is elastically deformed, and the first hooking portion is pinned to the back plate. The guide portion for guiding the shoe hold pin when the second hook portion of the shoe hold pin shifts to the state of hooking the main hook portion of the second arm piece from the state hooked in the hole. 2. The shoe hold device for a drum brake according to claim 1, wherein the shoe hold device is provided on a second arm piece of the shoe hold spring.   3. The drum brake according to claim 2, wherein the temporary latching portion, the guide portion, and the main latching portion are formed symmetrically on both sides of the longitudinal center line of the second arm piece. Shoe hold device.   The drum brake shoe hold device according to any one of claims 1 to 3, wherein the temporary latching portion, the guide portion, and the main latching portion are slits having continuity.   The shoe hold pin is a pin obtained by bending a spring material into a bifurcated shape, and has a pair of connecting legs that can be closed and opened, and a second of the shoe hold spring is provided on one of the pair of connecting legs. A second latching portion that can be latched and pressed on the arm piece is formed, and a pair of second latching portions that can be latched on the side surface of the back plate is formed on the other side of the connecting leg. The shoe hold device for a drum brake according to claim 1 or 2.   6. The shoe holding device for a drum brake according to claim 5, wherein the pair of connecting legs are offset so that the pair of connecting legs of the shoe hold pins do not interfere with each other when the legs are closed.   The second latching portion includes two ear portions formed continuously with the connecting leg, and a pressing portion formed continuously between the two ear portions, via the pressing portion. The shoe hold device for a drum brake according to claim 1, 2 or 5, wherein the second arm piece can be pressed.

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