JP4619336B2 - Parking brake release device - Google Patents

Description

  The present invention is a parking brake that brakes by a spring force in a normal state and releases a parking brake using hydraulic pressure, for example, in a work vehicle or an industrial vehicle, and forcibly releases the parking brake when hydraulic pressure cannot be obtained. The present invention relates to a parking brake release device.

  Conventionally, as disclosed in Patent Document 1, a parking brake provided in a work vehicle, an industrial vehicle, or the like is a wet multi-plate disc brake with a built-in transmission. A negative type that releases the brake by hydraulic pressure in the operating state is adopted.

  In this Patent Document 1, a parking brake is released when the engine is stopped and hydraulic pressure is not obtained, and a release device that introduces the hydraulic pressure of a service brake that brakes the wheel to the parking brake is used for maintenance. There is provided a release device for introducing the hydraulic pressure of the manual greasing grease pump into the parking brake for release.

However, in Patent Document 1, since piping and maintenance are complicated, for example, a mechanical release device shown in FIG. 13 is provided.
In the parking brake 61 having this mechanical release device, a plurality of rotary brake discs 65 are attached to the distal end portion of the rotary shaft 63 via a mounting member 64 in the brake housing 62 of the transmission. A plurality of brake brake discs 66 disposed between the rotary brake discs 65 are attached. A brake piston 67 that presses and brakes the movable brake disc 65 via the brake brake disc 66 is disposed on the tip end side of the rotary shaft so as to be able to approach and separate in the direction of the rotary axis. Further, the brake piston 67 and the cap of the brake housing 62 are arranged. A plurality of braking springs 68 are interposed between 62a to urge the brake piston 67 to the pressing side for braking. A ring-shaped release oil chamber 69 that urges the brake piston 67 to the release side against the braking spring 68 is formed between the brake housing 62 and the brake piston 67 and is switched from a hydraulic pump driven by the engine. The release pressure oil is supplied to and discharged from the release oil chamber 69 via the valve, and the brake piston 67 is driven in the release direction in which the brake spring 68 is compressed.

The parking brake 61 release device includes a release screw hole 71 formed in the rotational axis of the brake piston 67 and a screw release plug hole 72 formed in the cap 62a so as to face the release screw hole 71. The closure plug 73 is detachably screwed into the release plug hole 72, and the release bolt 75 is held on the outer periphery of the housing cap 62a via the screw hole 74. When the parking brake 61 is forcibly released and the vehicle is pulled, for example, when the engine is stopped and no release pressure oil is supplied, the release bolt 75 is set as shown in FIG. Remove from the screw hole 74, remove the closing plug 73 from the release plug hole 72, insert a release bolt 75 into the brake housing 62 from the release plug hole 72, and screw the tip thread portion into the release screw hole 71 to release By further tightening the bolt 75, the brake piston 67 can be pulled toward the cap 62a to compress the braking spring 68, and the parking brake 61 can be released.
JP-A-7-323534

  However, in the mechanical release device described above, the release bolt 75 protrudes from the brake housing 62 of the transmission and is attached, requiring extra space, and removing the closing plug 73 from the release plug hole 72 allows oil to be removed. There have been problems such as leakage and the possibility that dirt and foreign matter may enter the brake housing 62 by inserting the release bolt 75 into the brake housing 62 from the release plug hole 73.

  An object of the present invention is to provide a parking brake release device that solves the above-described problems, does not require extra space, does not leak oil, and does not cause dust or foreign matter to enter the brake housing.

  According to a first aspect of the present invention, there is provided a rotary shaft that is rotatably supported in the brake housing, a plurality of rotary brake disks that are attached to the tip end side of the rotary shaft at regular intervals in the direction of the rotational axis, and a brake housing A plurality of brake brake discs attached and arranged with a predetermined gap between the rotary brake discs, and a brake piston arranged on the base end side of the brake brake disc so as to be movable within a predetermined range in the direction of the rotation axis; A brake spring that pressurizes and brakes the rotary brake disc via the brake brake disc by urging the brake piston toward the tip side, and a spring force of the brake spring formed between the brake piston and the brake housing by pressure oil A parking brake having a release oil chamber for releasing the braking by moving the brake piston to the base end side against the This release device has a base end abutting against the brake piston, and a plurality of release pins that are slidably contained in or projecting through insertion holes formed in the front end surface of the brake housing. A release member having a holding portion that is attached in a steady posture along the distal end surface of the brake housing and covers the opening of the insertion hole is provided so that the posture can be changed, and the posture of the release member is changed from the normal posture to the release posture. A release portion is provided that pushes the release pin to push the brake piston back from the braking position to the release position.

  According to the first aspect of the invention, the release member is changed to the release posture from the normal posture in which the insertion hole and the distal end side of the release pin are covered by the holding portion, so that the release pin is pushed by the release portion and the brake piston is The parking brake in the braking state can be released by moving from the braking position to the release position. Therefore, only by installing the release member along the front end surface of the brake housing, there is no protruding member and no extra space is required. Moreover, since the release pin is fitted in the insertion hole, there is no oil leakage. Furthermore, no member is inserted into the brake housing from the outside, and there is no possibility that dust or foreign matter will enter the brake housing.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Embodiment 1]
A parking brake 21 provided in a work vehicle, an industrial vehicle, or the like will be described with reference to FIGS.

  As shown in FIGS. 5 and 6, the transmission 10 provided with the parking brake 21 includes an input shaft 12 that is rotated through a torque converter 11, and a reverse shaft that is rotated by a gear through the input shaft 12. 13 and the forward shaft 14, the reverse shaft 15 rotated by the reverse shaft 13 through a gear and a clutch, the intermediate shaft 16 rotated by the forward shaft 14 and the reverse shaft 15 by a gear, and the intermediate shaft 16 A low-speed transmission shaft (rotary shaft) 17 and a high-speed transmission shaft 18 that are rotated via a gear and a clutch, and an output shaft 19 that is rotated by the low-speed transmission shaft 17 and the high-speed transmission shaft 18 via a gear. Yes. The parking brake 21 is disposed at one end of the low speed transmission shaft 17 in a brake chamber 23 in a brake housing 22 provided integrally with the transmission case 10a.

  As shown in FIGS. 1 to 3, in the brake chamber 23, a low speed transmission shaft 17 that is rotatably supported around a rotation axis O via a bearing 24 extends from the base end portion on the transmission case 10 a side. Projected to the surface side. The brake housing 22 is formed integrally with the transmission case 10a to support the bearing 24, a base end wall portion 22b, a base end cylindrical portion 22c protruding from the transmission case 10a toward the front end, and the base end cylindrical portion. The housing main body 22a is formed by the disk support cylinder 22d attached to the 22c via the attachment bolt 25a, and the cap 22f is attached to the opening 22e at the front end surface of the disk support cylinder 22d via the attachment bolt 25b and closed. Has been.

  A cylindrical disc mounting member 26 is attached to the tip spline portion 17 a of the low speed transmission shaft 17, and a plurality of ring plate-like rotary brake discs 27 are fixed in the direction of the rotational axis O on the outer periphery of the disc mounting member 26. It is attached at every interval. On the other hand, a plurality of brake brake disks 28 are provided in the disk support cylinder 22d of the housing body 22a with a predetermined gap between the rotary brake disks 27.

  Further, on the base end side of the brake brake disc 28, a brake piston 29 loosely fitted to the low speed transmission shaft 17 is disposed in the base end cylindrical portion 22c of the housing body 22a so as to be slidable within a predetermined range in the direction of the rotation axis O. A ring-shaped pressure pad 29 a that is in contact with the brake brake disk 28 is attached to the front end surface of the piston 29. Further, between the brake piston 29 and the base end wall portion 22b of the housing main body 22a, the brake piston 29 is urged toward the distal end around the low speed transmission shaft 17 and is rotated by the brake brake disc 28 via the pressure pad 29a. A plurality of braking springs 30 that press the brake disc 27 and brake the low-speed transmission shaft 17 are interposed.

  Furthermore, the brake piston 29 is urged to the proximal end side by pressure oil between the stepped portion of the outer peripheral portion of the brake piston 29 having a small diameter on the distal end side and the proximal end cylindrical portion 22c and the disk support cylinder 22d of the housing body 22a. A ring-shaped release oil chamber 31 is formed, and a pressure oil port 32 communicating with the release oil chamber 31 is formed in the proximal end cylindrical portion 22c.

  The release device 41 that forcibly releases the parking brake 21 when pressure oil is not supplied to the release oil chamber 31, for example, when the engine is stopped, is a disc support cylinder 22d of the housing main body 22a and an outer peripheral portion of the brake brake disc 28, a cap 22f, In addition, a pair of upper and lower insertion holes 42a and 42b parallel to the rotation axis O are formed at symmetrical positions of the rotation axis O, and release pins 43 are slidably fitted into the insertion holes 42a and 42b, respectively. . The release pin 43 has a base end abutted against the brake piston 29 in a braking state at a normal position shown in FIG. 3, and a tip end portion of the release pin 43 on the surface of the cap 22f with a predetermined length, for example, D1 (more than the release distance LA) ) So as to project only by a length L. Further, the release pin 43 is fitted into the insertion hole 42b of the cap 22f to prevent oil from leaking, and a seal ring (oil seal member) 43a is attached to the insertion hole 42b so as to prevent oil from leaking. Leakage is reliably prevented. Even if the release pin 43 moves to the release position, the seal ring 43a is positioned and sealed in the insertion hole 42b.

  Further, a release bar (release member) 44 is disposed in the up-down direction along the surface of the cap 22f. That is, the cap 22f is formed with a threaded mounting hole 45 on the rotational axis O, and a fixing bolt (fixed) is fixed to the mounting hole 45 from the mounting hole 44a penetrating the rotational axis O of the release bar 44. ) 46 is mounted, and the release bar 44 is detachably mounted. As shown in FIG. 3, in a normal posture in which a normal parking brake 21 is braked and released, a holding recess having a depth D <b> 1 that accommodates the tip of the release pin 43 on both sides of the release bar 44. (Holding part) 44b is formed. Further, a release recess (release portion) 44c into which the tip of the release pin 43 is fitted is formed on the surface of the release bar 44 on the opposite side of the holding recess 44b. The depth D2 of the release recess 44c is shallower than the depth D1 of the holding recess 44b by the release distance LA with the brake piston 29 at the braking position as the release position. Therefore, when the parking brake 21 is forcibly released, the fixing bolt 46 is removed, and the release bar 44 in the normal posture is reversed and attached in the release posture.

  In the above configuration, when the vehicle travels, the parking brake 21 is supplied with pressure oil from the hydraulic pump driven by the engine via the pressure oil port 32 to the release oil chamber 31, and against the brake spring 30, the brake piston 29 is in a release posture retracted to the base end side. When the parking brake lever (not shown) is pulled (or the parking brake is switched on) when the vehicle is stopped, the switching valve (not shown) is operated to discharge the pressure oil in the release oil chamber 31, and the braking spring 30 The brake piston 29 is energized to enter a braking position where the rotary brake disc 27 is pressed via the brake brake disc 28, whereby the low speed transmission shaft 17 is braked and the parking brake 21 is put into a braking state.

  Furthermore, when the parking brake 21 is forcibly released when the engine is stopped and the release hydraulic pressure cannot be supplied to the release oil chamber 31 from the hydraulic pump via the pressure oil port 32, the fixing bolt 46 is loosened and removed to release the normal posture. The bar 44 is removed from the cap 22f and turned upside down, the release recess 44c is fitted to the tip of the release pin 43, and the fixing bolt 46 is attached and tightened again to obtain the release posture. As a result, the release pin 43 is pushed into the base end side by the release distance LA in the release recess 44c, and the brake piston 29 at the braking position is pushed back to the release position on the base end side against the braking spring 30 to release the braking state. be able to.

  According to the above embodiment, the release bar 44 is attached by the fixing bolt 46 along the surface of the cap 22f by the fixing bolt 46, so that there is no protrusion protruding from the brake housing 22 as in the prior art, and extra Space is also unnecessary. Further, since the release pin 43 is always fitted in the insertion hole 42b and is further oil-sealed by the seal ring 43a, oil release does not occur as in the conventional case, and the release operation can be easily performed. Further, there is no member that is inserted into the brake chamber 23 from the outside as in the conventional case, and there is no possibility that dust and foreign matter enter the brake chamber 23. Furthermore, since it is only necessary to turn over the release bar 44 and mount it again, the release operation can be easily performed in a short time. Further, since the storage hole 4b is formed on the back surface of the release bar 44 and the release recess 44c is formed on the front surface, the release recess 44c of the inverted release bar 44 is fitted to the tip of the release pin 43 during the release operation. Thus, the release bar 44 can be easily positioned.

FIGS. 7A to 7C show second to fourth forms in which the holding recess 44b and the release recess 44c formed in the release bar 44 are modified.
In the second embodiment shown in FIG. 7A, the holding portion is a holding recess 44e formed at a depth of the release distance LA, and the release portion is a flat release portion 44f. Further, in the third embodiment shown in FIG. 7B, the holding portion is a flat holding portion 44g, and the release portion is a release convex portion 44h having a height of the release distance LA. Further, in the fourth embodiment shown in FIG. 7C, the holding portion is a holding convex portion 44i having a predetermined height H1, and the releasing portion is a releasing convex portion 44j formed at a height H2. The height H1 of the holding projection 44i + the release distance LA = the height H2 of the release projection 44j.

According to the modifications 2 to 4, the same operational effects as those of the first embodiment can be obtained.
FIG. 8 shows a modification of the fixing member for the release member. In the first embodiment, the fixing tool for attaching the release bar 44 to the cap 22f is the fixing bolt 46 to be attached to the attachment hole 45 and the attachment hole 44a on the rotation axis O. However, in this modified example, the cap Corresponding to the bolt holes of the mounting bolts 25b for fixing 22f to the housing body 22a, a pair of mounting holes 44d are formed at both ends of the release bar 44, and the corresponding mounting bolts 25b are removed from the bolt holes and fixed. The bolt 46 is attached to the bolt hole of the mounting bolt 25b from the mounting hole 44d. Thereby, it is not necessary to form the mounting hole 45 on the axis O with the cap 22f. In addition, the 2nd form-the 4th form of the holding | maintenance recessed part and cancellation | release recessed part which are shown to FIG.

[Embodiment 2]
The second embodiment will be described with reference to FIGS. 9 and 10A. In the first embodiment, the release bar 44 is reversed from the normal posture to the release posture, and the holding concave portion 44b and the release concave portion 44c are arranged on the front and back surfaces of the release bar 44. A certain release plate (release member) 51 is rotated from a steady posture by a posture change angle θ set to a predetermined angle, for example, in a range of 20 ° to 45 °, to obtain a release posture. The same members as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  That is, the release plate 51, which is a release member, has a mounting hole 44a penetrating on the rotation axis O, and via a fixing bolt 46, a normal posture and a release posture separated from the normal posture by a posture change angle θ. It is supported so that it can be rotated and fixed between the two. The release plate 51 has a holding recess 51b in which the tip end of the release pin 43 is fitted in a steady posture, separated by a posture change angle θ on the same arc centered on the mounting hole 51a, and released in the release posture. A release recess 51 c into which the tip of the pin 43 is fitted and the release pin 43 is pushed is formed.

  As shown in FIG. 9A, in this first embodiment, the holding recess 51b is set to a depth D1 that can accommodate the tip of the release pin 43, and the release recess 51c is released to the depth D1 of the holding recess 51b. D2 is obtained by subtracting the distance LA.

  Therefore, when the parking brake 21 is forcibly released, the fixing bolt 46 of the release plate 51 in the steady posture is loosened to disengage the holding recess 51b from the tip of the release pin 43, and the release plate 51 is moved to the posture change angle θ. The release recess 51c is fitted to the tip of the release pin 51, and the fixing bolt 46 is tightened again. The release pin 43 is pushed from the steady position to the release position by the release distance LA by the release recess 51c, and the brake piston 29 in the braking state is pushed back to the release position on the base end side against the braking spring 30 to release the braking state. can do.

  According to the above configuration, in addition to the effects of the first embodiment, it is not necessary to remove the fixing bolt 46 from the cap 22f, and the parking brake 21 can be released more easily. In addition, since the holding recess 51b and the release recess 51c are provided on the back surface of the release plate 51, foreign matter does not clog the recesses 51b and 51c and cannot be used.

  In addition, the 2nd form-4 form which deform | transformed the holding | maintenance part and cancellation | release part of the cancellation | release plate 51 are shown to FIG.10 (b)-(d). That is, in the second embodiment shown in FIG. 10B, the holding portion is a holding recess 51e formed at a depth of the releasing distance LA, and the releasing portion is a flat releasing portion 51f. Further, in the third embodiment shown in FIG. 10C, the holding portion is a flat holding portion 51g, and the release portion is a release convex portion 51h having a height of the release distance LA. Furthermore, in the 4th form shown in FIG.10 (d), the holding | maintenance part is made into the holding convex part 51i which has the predetermined height H1, and it was set as the cancellation | release convex part 51j formed in height H2 in the cancellation | release part. The height H1 of 51h + the release distance LA = the height H2 of the release convex portion 51j.

According to the 2nd-4th form, there can exist an effect similar to a 1st form.
[Embodiment 3]
The third embodiment will be described with reference to FIGS. 11 and 12A. In the second embodiment, when changing from the steady posture to the release posture, it is necessary to disengage the tip of the release pin 43 from the holding recess 44b and to fit the release recess 44c. Then, it is only necessary to loosen the fixing bolt 46 and rotate the release plate (release member) 52 by the posture change angle θ. The same members as those of the second embodiment are denoted by the same reference numerals and description thereof is omitted.

  The release plate 52 that is a release member is formed with a bolt hole 52 a on the rotation axis O and is rotatably supported by a fixing bolt 46. In addition, a holding recess 52b having a depth D1 in which the tip of the release pin 43 abuts in a steady posture is formed at one end on the same arc separated from the bolt hole 52a by the posture change angle θ around the bolt hole 52a. A release recess 52c having a depth D2 with which the tip of the release pin 43 abuts in the release posture is formed. The holding recess 52b and the release recess 52c are connected by a tapered recess (guide portion) 52d. Here, the depth D2 of the release recess 52c having the depth D2 is the depth D1 of the holding recess 52b-the release distance LA.

  Therefore, when the parking brake 21 is forcibly released, the release plate 52 in the normal posture is rotated by the posture change angle θ, and the tip end portion of the release pin 43 is changed from the holding recess 52b to the release recess 52c via the tapered recess 52d. By making the release posture by sliding, the release pin 43 is pushed by the release distance LA, the brake piston 29 in the braking position is pushed back to the release position against the braking spring 30, and the braking state can be released.

  According to the above configuration, in addition to the operational effects of the second embodiment, the parking brake 21 can be released and returned by a simple operation by simply loosening the fixing bolt 46 and rotating the release plate 51 by the posture change angle θ. Operation is easier.

  In addition, the 2nd-4th form which deform | transformed the holding | maintenance part and cancellation | release part of the cancellation | release plate 52 is shown to FIG.12 (b)-(d). That is, in the second embodiment shown in FIG. 12B, the holding portion is a holding recess 52e formed at a depth of the release distance LA, the release portion is a flat release portion 52f, and the holding recess 52e and the flat release portion 52f are Are connected via a tapered recess (guide portion) 52g. In the third embodiment shown in FIG. 12C, the holding portion is a flat holding portion 52h, the release portion is a release convex portion 52i having a height of the release distance LA, and the flat holding portion 52g and the release convex portion 52h are The cap 22f has an arcuate taper groove 53a that guides the taper ridge 52i and an arcuate parallel groove 53b that guides the release protrusion 52g. Is formed. Furthermore, in the 4th form shown in FIG.12 (d), the holding | maintenance part is set as the holding convex part 52k formed in the predetermined height H1, and it is set as the cancellation | release convex part 52m formed in the height H2 in the cancellation | release part, and holding | maintenance convex part 52k. And the release convex part 52m are connected via a taper convex part (guide part) 52n, the cap 22f has an arcuate guide groove part 53c for guiding the holding convex part 52k and the taper convex part 52n, and a release convex part 52m. An arc-shaped parallel groove portion 53d is formed. Here, the height H1 of the holding projection 52k + the release distance LA = the height H2 of the release projection 44m.

  According to the 2nd-4th form, there can exist an effect similar to a 1st form.

1 is a side view showing a first embodiment of a parking brake according to the present invention. It is AA sectional drawing shown in FIG. 1 of a braking state. FIG. 3 is an enlarged view of a main part of FIG. 2. It is a principal part enlarged view which shows the cancellation | release state of the cancellation | release apparatus of a parking brake. It is a longitudinal cross-sectional view of the transmission which provided the parking brake. It is a side view which shows the transmission which provided the parking brake. Sectional drawing which shows the 2nd form-the 4th form which changed the storage crevice and release crevice of a release bar, (a) shows the 2nd form which made a holding part a holding crevice and made a release part a flat release part, b) shows a third form in which the holding part is a flat holding part and the release part is a release convex part, and (c) shows a fourth form in which the hold part is a holding convex part and the release part is a release convex part. . It is a side view which shows the modification of the fixing tool of a parking brake. It is a side view which shows Embodiment 2 of the cancellation | release member in a cancellation | release apparatus. FIG. 9B is a sectional view taken along the line B-B in FIG. 9 showing a modified form of the release plate holding portion and the release portion. FIG. 9A shows a first mode in which the holding portion is a holding recess and the release portion is a release recess. ) Shows a second form in which the holding part is a holding concave part and the releasing part is a flat releasing part, and (c) shows a third form in which the holding part is a flat holding part and the releasing part is a releasing convex part. d) shows the 4th form which made the holding | maintenance part the holding convex part and made the cancellation | release part the cancellation | release convex part. It is a side view which shows Embodiment 3 of the cancellation | release member in a cancellation | release apparatus. FIG. 11 is a cross-sectional view taken along the line CC of FIG. 11 showing a modified form of the holding portion and the releasing portion of the release plate. FIG. ) Shows a second form in which the holding part is a holding concave part and the releasing part is a flat releasing part, and (c) shows a third form in which the holding part is a flat holding part and the releasing part is a releasing convex part. d) shows the 4th form which made the holding | maintenance part the holding convex part and made the cancellation | release part the cancellation | release convex part. It is a center longitudinal cross-sectional view which shows the conventional parking brake. It is a center longitudinal cross-sectional view which shows the forced state of the conventional parking brake.

Explanation of symbols

10 Transmission 17 Low speed transmission shaft (rotary shaft)
21 Parking brake 22 Brake housing 22a Housing body 22f Cap 23 Brake chamber 25a, 25b Mounting bolt 26 Disc mounting member 27 Rotating brake disc 28 Brake brake disc 29 Brake piston 30 Brake spring 31 Release oil chamber 32 Pressure oil port 41 Release device 42a 42b Insertion hole 43 Release pin 43a Seal ring 44 Release bar (release member)
44a, 44d Mounting hole 44b Holding recess 44c Release recess 45 Mounting hole 46 Fixing bolt (fixing tool)
51 Release plate (release member)
51a Mounting hole 51b Holding recess 51c Release recess 52 Release plate (release member)
52a Mounting hole 52b Holding recess 52c Release recess 52d Taper recess (guide part)

Claims (5)

A rotary shaft rotatably supported in the brake housing, a plurality of rotary brake discs attached to the front end side of the rotary shaft at regular intervals in the rotational axis direction, and a rotary housing attached to the brake housing between the rotary brake discs A plurality of brake brake discs arranged with a predetermined gap, a brake piston arranged on the base end side of the brake brake disc so as to be movable within a predetermined range in the rotational axis direction, and the brake piston attached to the tip side The brake spring that pressurizes and brakes the rotary brake disc via the brake brake disc, and the brake piston that is formed between the brake piston and the brake housing against the spring force of the brake spring by the pressure oil. A parking brake release device comprising a release oil chamber that moves to the end side to release braking.
Provided with a plurality of release pins that are slidably contained in or projecting into an insertion hole formed in the distal end surface of the brake housing, with the proximal end abutting against the brake piston,
A release member having a holding portion that is attached in a steady posture along the distal end surface of the brake housing and covers the opening of the insertion hole is provided so that the posture can be freely changed.
The parking brake release device, wherein the release member is provided with a release portion that pushes the release pin and pushes the brake piston back to the release position by changing the posture from a normal posture to a release posture. While the holding part is formed on the back surface of the release member, the release part is formed on the surface of the release member,
The parking brake release device according to claim 1, wherein the release member is provided with a fixture that can be attached / detached / fixed between a normal posture and a release posture that are reversed upside down. The release member is rotatably supported around the rotation axis, and on the back surface of the release member, the holding portion and the release portion are formed at the same radial position of the rotation axis,
The parking brake release device according to claim 1, wherein the release member is provided with a fixture that can be rotated and fixed between a normal posture and a release posture rotated by a predetermined angle. The parking brake release device according to claim 3, wherein the release member is provided with a guide portion that is connected to the holding portion and the release portion and guides a tip portion of the release pin. The brake housing has a housing main body having an opening at a front end surface, and a cap attached to the opening.
The parking brake release device according to any one of claims 1 to 4, wherein an insertion hole is formed in the cap, and an oil seal member is provided in a gap between the insertion hole and the release pin.

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