JP2022090347A - Wedge cam type brake - Google Patents

Abstract

To provide a wedge cam type brake which enables easy adjuster return operation in which an axial position of a wedge cam relative to a spindle is returned to a position before gap adjustment.SOLUTION: In a wedge cam type brake, a spindle 13, with which a wedge cam 20 is threadedly engaged in a reversible manner, is pressed and driven by an air piston 16 to perform brake operation. The wedge cam type brake includes: a chamber spring 17 which biases the air piston 16 to a non-brake position opposite to a driving direction; a fixed member 45 fixed to a brake body side stationary part through a rotation prevention mechanism 61; a rotary member 51 which engages with the other end part of the spindle 13 in such a manner that the rotary member cannot rotate relative to the other end part and can move in a rotation axis direction; and a one-way clutch 65 which is provided between the fixed member 45 and the rotary member 51 and allows rotation of the spindle 13 only in one direction so as to transmit rotational force of the spindle 13 only in a direction such that the wedge cam 20 is moved to the brake position side.SELECTED DRAWING: Figure 2

Description

The present invention relates to a wedge cam type brake.

Conventionally, in disc brakes for vehicles equipped with brakes, especially for railway vehicles that require strong braking force, the cam action of the wedge cam expands the base ends of the pair of brake arms to the open ends. A wedge cam type brake is known in which a provided pad assembly is pressed from both sides of a brake rotor to perform a braking operation.

These wedge cam type brakes have a problem that when the pad of the pad assembly wears, the time when the brake starts to work is delayed and the braking distance becomes long. Therefore, an automatic clearance adjusting mechanism is provided in the middle portion of the spindle on which the wedge cam is formed so that the brake arm does not generate an excessive stroke due to wear of the pad.
However, in the wedge cam type brake provided with such an automatic clearance adjustment mechanism, there is a problem that the response time (time required for gripping the brake rotor) increases in proportion to the amount of wear of the pad in the pad assembly. was there. That is, as the amount of pad wear increases, the relative position of the air piston (fluid pressure piston) with respect to the air cylinder moves downward. Therefore, since the cylinder volume of the air cylinder to be pressurized increases and the pressurizing time increases, the response time increases and the responsiveness deteriorates. Therefore, Patent Document 1 below discloses a wedge cam type brake provided with an automatic position adjusting mechanism for always operating the brake with a constant response time regardless of the amount of pad wear.

A wedge cam type brake equipped with an automatic brake adjuster device equipped with such an automatic clearance adjustment mechanism and an automatic position adjustment mechanism is an automatic brake when replacing a pad assembly with a worn pad with a new pad assembly. It is necessary to release the adjuster device to return the axial relative position of the spindle to the wedge cam to the initial position.

Japanese Unexamined Patent Publication No. 2016-169802

However, in the conventional wedge cam type brake provided with the above-mentioned auto adjuster device for a brake, the work of returning the adjuster to return the axial position of the wedge cam with respect to the spindle before adjusting the clearance is complicated.
That is, in order to release the adjuster, it is first necessary to remove the caliper body from the support fixed to the vehicle body and remove the rotation stopper member that prevents the spindle from rotating. Then, after rotating the spindle to the return side and screwing the rotating member toward the air piston side together with the wedge cam, it is necessary to repeat the operation of knocking up the sleeve of the automatic clearance adjustment mechanism while holding the spindle so that it does not rotate. , The adjuster return work was complicated.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a wedge cam type brake in which an adjuster return operation for returning an axial position of a wedge cam with respect to a spindle before adjusting a clearance is easy.

The above object according to the present invention is achieved by the following configuration.
(1) The spindle to which the wedge cam is reversibly screwed moves to the braking position along the rotation axis direction of the spindle by pressing and driving one end of the spindle in the rotation axis direction by the fluid pressure piston. A wedge cam type brake in which the base end portion of the brake arm is expanded by the cam action of the wedge cam, and a pair of pad assemblies provided at the open end portions are pinched from both sides of the brake rotor to perform a braking operation. There,
An elastic member that urges the fluid pressure piston to a non-braking position opposite to the driving direction,
A fixing member fixed to the stationary part on the brake body side via a detent mechanism,
A rotating member that cannot rotate relative to the other end of the spindle and is movably engaged in the direction of the axis of rotation.
A mechanism provided between the fixing member and the rotating member that allows rotation in only one direction in order to transmit the rotational force of the spindle only in the direction in which the wedge cam is moved toward the braking position side.
Wedge cam type brake equipped with.

According to the wedge cam type brake having the configuration of (1) above, when the brake is activated, it is reversibly screwed to the wedge cam mounted so as to be movable in the axial direction with respect to the brake body and not to rotate relative to the brake body. When one end of the spindle is pressed and driven in the direction of the rotation axis by the fluid pressure piston, the spindle tends to rotate in the direction of moving the wedge cam toward the non-braking position side. Here, between the rotating member engaged with the other end of the spindle and the fixing member fixed to the stationary portion on the brake body side, the rotational force of the spindle is applied only in the direction of moving the wedge cam to the braking position side. A mechanism (for example, one-way clutch or ratchet mechanism) that allows rotation in only one direction is provided for transmission (in other words, the rotational force of the spindle is not transmitted in the direction of moving the wedge cam to the non-braking position side). Has been done. Therefore, the spindle whose one end is pressed and driven by the fluid pressure piston when the brake is operated cannot rotate in the direction of moving the wedge cam to the non-braking position side with respect to the wedge cam, and accompanies the wedge cam along the rotation axis direction. Move to the braking position side. Then, the wedge cam that has moved to the braking position side expands the base end portion of the brake arm by the cam action, and presses the pair of pad assemblies provided at the open end portions from both sides of the brake rotor to perform the braking operation. It can be performed.
Then, during the normal stroke (within a predetermined stroke) accompanying the brake operation, when the brake operation is released, the elastic member urges the fluid pressure piston to the non-braking position, and the spindle is in the non-braking position together with the fluid pressure piston. Return to. At this time, the spindle moves in the axial direction without rotating due to the frictional resistance of the screwed portion with the wedge cam.
On the other hand, when an excessive stroke (more than a predetermined stroke) occurs due to pad wear due to the brake operation, the brake operation is released, and the spindle moves back by a predetermined stroke or more in the drive direction due to the urging force of the elastic member. At that time, the frictional resistance of the screwed portion with the wedge cam becomes small. Therefore, when the spindle returns to the non-braking position together with the fluid pressure piston when the brake is released, the spindle can rotate in the direction of moving the wedge cam toward the braking position with respect to the wedge cam. At this time, the mechanism provided between the fixing member and the rotating member that allows rotation in only one direction allows the spindle to rotate in the direction of moving the wedge cam toward the braking position. As a result, the spindle rotates with respect to the wedge cam and the screwing proceeds, so that the initial position of the wedge cam in the axial direction with respect to the fluid pressure piston is adjusted, and the clearance is automatically adjusted against pad wear. Therefore, the wedge cam type brake of this configuration can always operate the brake with a constant response time regardless of the amount of pad wear when the brake is operated.
Further, when the worn pad is replaced with a new pad, the fixing member is released from the detent mechanism to cancel the operation of the mechanism that allows rotation in only one direction. Then, the axial position of the wedge cam with respect to the fluid pressure piston can be returned to the position before the clearance adjustment only by rotating the spindle in the direction in which the wedge cam moves to the non-braking position side. Therefore,
The adjuster return work that returns the axial position of the wedge cam with respect to the spindle before the clearance adjustment becomes easy.

(2) The detent mechanism
With the engaging recess formed in the fixing member,
An engaging pin provided in the stationary portion on the brake body side and capable of switching between an engaging position that engages with the engaging recess and a non-engaging position that disengages from the engaging recess.
The wedge cam type brake according to (1) above.

According to the wedge cam type brake having the configuration of (2) above, the detent mechanism for fixing the fixing member to the stationary portion on the brake body side is easily configured by the engaging recess and the engaging pin of the fixing member, and the fixing member. Can be easily switched between fixed and non-fixed.

(3) The rotating jig inserted into the through hole formed in the direction intersecting the rotation axis direction of the rotating member is
The wedge cam type brake according to (1) or (2) above, which can abut on the other end of the spindle and restrict the movement of the spindle in the rotation axis direction toward the braking position side.

According to the wedge cam type brake having the configuration of (3) above, when the rotating jig is used to rotate the spindle in order to return the axial position of the wedge cam with respect to the fluid pressure piston before the clearance adjustment, the rotating jig brakes. Restrict the movement of the spindle in the direction of the rotation axis to the position side. Therefore, the spindle rotated by the rotating jig can surely screw the wedge cam to the non-braking position side without being moved to the braking position side by the reaction force of the wedge cam to be screwed.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a wedge cam type brake that facilitates the adjuster return work of returning the axial position of the wedge cam with respect to the spindle before adjusting the clearance.

It is a side view which shows the whole structure of the wedge cam type brake which concerns on one Embodiment of this invention. FIG. 2 is a cross-sectional view taken along the line II-II of the wedge cam type brake shown in FIG. It is sectional drawing which shows the spindle and the wedge cam in the wedge cam type brake shown in FIG. It is an exploded perspective view explaining the spindle and the wedge cam shown in FIG. FIG. 3 is an exploded perspective view illustrating a mechanism provided between a fixing member and a rotating member in the wedge cam type brake shown in FIG. 2 and allowing rotation in only one direction of the spindle. It is sectional drawing of the main part which shows the brake operation state of the wedge cam type brake shown in FIG. 2 is a cross-sectional view of a main part for explaining the detent mechanism of the wedge cam type brake shown in FIG. 2, where FIG. 2A shows an engagement position where an engagement pin engages with an engagement recess, and FIG. 2B shows an engagement position. Indicates a non-engagement position where the engagement pin disengages from the engagement recess. It is sectional drawing of the main part which shows the state which the rotating jig is inserted into the through hole of a rotating member.

Hereinafter, suitable embodiments for carrying out the wedge cam type brake of the present invention will be described with reference to the drawings.

Hereinafter, the structure of the wedge cam type brake according to the embodiment of the present invention will be described with reference to FIGS. 1 to 5.
FIG. 1 shows the overall structure of a disc brake for a railroad vehicle equipped with a wedge cam type brake, the body 1 is fixed to the vehicle body side via a support 2, and a pair of brake arms 3 and 3 are on the opposite side of the support 2. The intermediate portion of 3 is pivotally supported by the brake arm shafts 4 and 4, respectively.
Pad assemblies 6 and 6 are mounted on the open ends (opposite sides of the support 2) of the brake arms 3 and 3 via the pad holder 5.

FIG. 2 shows the II-II cross section of the wedge cam type brake of FIG. 1 in the initial state in which the brake is not activated. The outer end of the 7 is supported by the spherical bush 8, and the inner ends of the link rods 7 and 7 are connected to and supported by the roller arms 10 and 10 by the spherical bush 9. The lower ends of the roller arms 10 and 10 are pivotally supported at both ends of the strut 12 via bearings 11 and 11 to form a link type booster.

In FIG. 2, an air cylinder 14 is disposed above the spindle 13, and when air is introduced from a supply port to operate the brake and the pneumatic chamber inside the air cylinder 14 is filled, air is introduced. The piston (fluid pressure piston) 16 is operated downward against the restoring force of the chamber spring (elastic member) 17.

That is, in the wedge cam type brake according to the present embodiment, the spindle 13 to which the wedge cam 20 is reversibly screwed is driven by the air piston 16 by pressing one end of the spindle 13 in the direction of the rotation axis. The base ends of the brake arms 3 and 3 are expanded by the cam action of the wedge cam 20 that has moved to the braking position along the direction of the rotation axis of the brake arm 3, and a pair of pad assemblies 6 and 6 provided at the open ends thereof. Is pressed from both sides of the brake rotor 100 to perform the braking operation.

As shown in FIGS. 3 and 4, the spindle 13 arranged on the lower surface of the air piston 16 rotates with respect to the spring seat 32 via the thrust bearing 36 arranged at one end (upper end in the drawing). It is slightly movable and rotatably supported in the axial direction.
That is, the spring seat 32 penetrating the support hole 32a by one end of the spindle 13 is placed on the flange 13a formed on the one end side of the spindle 13, and is placed on the other end side of the spindle 13 (the lower end in the drawing). Movement to the side) is restricted. A bush 39, which is a slide bearing, is inserted between the inner peripheral surface of the support hole 32a and the outer peripheral surface of the spindle 13. Further, a washer 35, a wave washer 37, and a thrust bearing 36 are fitted and inserted into one end of the spindle 13, and a retaining ring 34 fitted in an annular groove 13b formed on an outer peripheral surface of the one end of the spindle 13 is used. It will be stopped. Therefore, the spindle 13 is slightly movable and rotatably supported in the rotation axis direction with respect to the spring seat 32. In particular, when the spindle 13 is pulled up in the direction of the rotation axis by the spring seat 32 operated on the upper side, the spindle 13 whose rotational resistance is reduced by the thrust bearing 36 is configured to be easily rotated with respect to the spring seat 32. Has been done.
Then, the spring seat 32 causes the spindle 13 to act on the driving force of the air piston 16 that operates downward.

A wedge cam 20 is reversibly screwed on one end side of the spindle 13 via a nut member 38 and is arranged coaxially with the spindle 13. The nut member 38 screwed into the reversible screw 50 of the spindle 13 is interposed between the spindle 13 and the wedge cam 20. The nut member 38 cannot move in the rotation axis direction and cannot rotate relative to the wedge cam 20 due to the pair of keys 40 arranged on the outer peripheral surface and the retaining ring 34 arranged on the upper surface via the spacer 33. It is configured integrally with the wedge cam 20.
A sleeve 70 having an outer peripheral surface having a rectangular cross section is fixed to the other end side of the spindle 13.

Further, the wedge cam 20 is attached so as to be movable in the axial direction and non-relatively rotatable with respect to the sleeve member 22 supported by the body 1 which is a stationary portion on the brake body side. Then, as the wedge cam 20 moves toward the tip end side (lower side) in the axial direction, the cam rollers 18 and 18 attached to the upper ends of the roller arms 10 and 10 ride on the inclined surface of the wedge cam 20.

By riding the cam rollers 18 and 18 on the inclined surface of the wedge cam 20, the roller arms 10 and 10 swing in the expanding direction, and are connected to the substantially intermediate portion of the roller arms 10 by the spherical bushes 9 and 9. The supported link rods 7 and 7 are pivoted outward (in the left-right direction in FIG. 2) by boosting them according to the principle of leverage. As a result, the base ends of the brake arms 3 and 3 are moved in the expanding direction with the brake arm shafts 4 and 4 as the swing center, and the pad assembly 6 arranged at the open ends of the brake arms 3 and 3 is arranged. , 6 are pressed against the brake rotor 100 (see FIG. 1) to perform the braking operation.

Further, in the wedge cam type brake according to the present embodiment, on the other end side (lower end side in FIG. 2) of the spindle 13, the lower surface of the body 1 which is a stationary part on the brake body side via the detent mechanism 61. It is provided between the fixing member 45 fixed to the fixing member 45, the rotating member 51 which is non-rotatably engaged with the other end of the spindle 13 and movably engaged in the direction of the rotation axis, and between the fixing member 45 and the rotating member 51. The one-way clutch 65, which is a mechanism that allows rotation in only one direction in order to transmit the rotational force of the spindle 13 only in the direction in which the wedge cam 20 is moved to the braking position side, is provided.

As shown in FIGS. 2 and 5, the fixing member 45 according to the present embodiment is attached to the lower surface of the body 1 and is a stationary portion on the brake body side with respect to the fixing base 41 via the detent mechanism 61. It is fixed. The fixing base 41 has a circular stepped opening 42 for rotatably accommodating a substantially cylindrical fixing member 45 and a pin accommodating portion 43 for accommodating an engaging pin 55, and is fastened and fixed to the lower surface of the body 1. Has been done.

In the fixing member 45, a plurality of engaging recesses 47 are formed at equal intervals along the outer peripheral surface, and an O-ring 68 is accommodated in the annular groove 48 formed on the upper surface and between the fixing member 45 and the lower surface of the body 1. Seal tightly. A substantially cylindrical rotating member 51 is fitted into the central opening 46 of the fixing member 45 via a one-way clutch 65. A lip seal 63 is provided between the inner peripheral surface of the central opening 46 and the outer peripheral surface of the rotating member 51, and is sealed liquid tightly.

The rotating member 51 has an opening 52 having a rectangular cross section, and a sleeve 70 fixed to the other end side of the spindle 13 is fitted so as to be relatively non-rotatable and movable in the rotation axis direction. A sliding plate 60 for enhancing slidability is arranged on each inner surface of the opening 52 on which the sleeve 70 slides. The sliding plate 60 is restricted from moving upward by a washer 67 arranged above the rotating member 51. Therefore, the wear of the sleeve 70 that moves in the direction of the rotation axis is suppressed, and the durability of the wedge cam type brake is improved. A dustproof cover 71 is attached to the lower end of the rotating member 51.

The detent mechanism 61 according to the present embodiment is accommodated in a plurality of engaging recesses 47 formed in the fixing member 45 and a pin accommodating portion 43 of the fixing base 41, and the tip portion engages with the engaging recess 47. An engaging pin 55 that can be switched between an engaging position and a non-engaging position that disengages from the engaging recess 47, and a coil spring 56 that elastically urges the engaging pin 55 housed in the pin accommodating portion 43 to the engaging position. , Equipped with.

The detent mechanism 61 has the engaging pin 55 housed in the pin accommodating portion 43 of the fixed base 41 with respect to the engaging recess 47 of the fixing member 45 rotatably accommodated in the stepped opening 42 of the fixed base 41. Engage with each other to prevent the fixing member 45 from rotating. The detented fixing member 45 is in a state of being fixed to the fixing base 41.
The engagement pin 55 has a pin accommodating portion 43 in a state of being elastically urged to the engaging position by fixing a retaining 57 to a rear end portion where a coil spring 56 is wound and the pin accommodating portion 43 is penetrated. Is housed in.

The one-way clutch 65 allows rotation of the rotating member 51 with respect to the fixing member 45 in only one direction. This one-way rotation is a rotation in a direction for transmitting the rotational force of the spindle 13 in the direction of moving the wedge cam 20 that is reversibly screwed toward the braking position side. Therefore, the spindle 13 having the other end fitted in the opening 52 of the rotating member 51 is allowed to rotate only in this one direction with respect to the fixing member 45.

FIG. 6 is a cross-sectional view of a main part showing a brake operating state of the wedge cam type brake shown in FIG.
As shown in FIG. 6, from the initial state in which the brake is not operated, the air piston 16 operates the spindle 13 on the other side in the axial direction (lower side in the drawing) against the restoring force of the chamber spring 17. Then, the rotatable spindle 13 reversibly screwed to the wedge cam 20 attached to the sleeve member 22 on the brake body side so as to be movable in the axial direction and non-rotatably relative to the sleeve member 22 is at one end by the air piston 16. Is pressed and driven in the direction of the rotation axis, and tries to rotate in the direction of moving the wedge cam 20 toward the non-braking position side.

Here, the wedge cam 20 is moved to the braking position side between the rotating member 51 engaged with the other end of the spindle 13 and the fixing member 45 fixed to the lower surface of the body 1 which is a stationary portion on the brake body side. Rotation is allowed in only one direction in order to transmit the rotational force of the spindle 13 only in the direction of movement (in other words, the rotational force of the spindle 13 is not transmitted in the direction of moving the wedge cam 20 to the non-braking position side). A one-way clutch 65 is provided. Therefore, the spindle 13 whose one end is pressed and driven by the air piston 16 when the brake is operated cannot rotate in the direction of moving the wedge cam 20 toward the non-braking position side with respect to the wedge cam 20, and the wedge 13 cannot rotate in the direction of the rotation axis. It moves to the braking position side with the cam 20. That is, the spindle 13 does not rotate, and the axial position of the wedge cam 20 with respect to the spindle 13 does not change.

Therefore, as shown in FIG. 6, in the wedge cam type brake, the brake is activated and the cam rollers 18 and 18 ride on the inclined surface of the wedge cam 20 that moves to the braking position side.
As a result, the pair of roller arms 10 and 10 pivotally supported by the bearings 11 and 11 at both ends of the strut 12 function as a link type booster, and the bearings 11 and 11 are expanded outward with the bearings 11 and 11 as shaft fulcrums, and the rollers are expanded. The link rods 7 and 7 connected and supported by the spherical bushes 9 and 9 to the substantially intermediate portion of the arms 10 and 10 are boosted by the principle of leverage and axially moved outward (in the left-right direction in the drawing). In this way, the base ends of the brake arms 3 and 3 are moved in the expanding direction with the brake arm shaft 4 as the swing center, and the pad assemblies 6 and 6 arranged at the open ends thereof are braked. The brake operation is performed by pinching the rotor 100.

Then, during the normal stroke (within a predetermined stroke) accompanying the brake operation, when the brake operation is released, the chamber spring 17 urges the air piston 16 to the non-braking position via the spring seat 32, and the air piston 16 and the air piston 16 At the same time, the spindle 13 returns to the non-braking position. At this time, the spindle 13 moves in the axial direction without rotating due to the frictional resistance of the screwed portion with the wedge cam 20.

On the other hand, when the lining is worn and the spindle 13 and the spring seat 32 are operated more than a predetermined value, the brake operation is released and the spring force of the chamber spring 17 is transmitted to the spindle 13 via the spring seat 32. The spindle 13 having a reversible screw rotates with respect to the wedge cam 20 due to the spring force of the chamber spring 17, and the relative positions of the wedge cam 20, the spindle 13 and the spring seat 32 change. As for the rotation of the spindle 13, the position adjustment of the piston is completed when the air piston 16 comes into contact with the air cylinder 14. Therefore, when the spindle 13 returns to the non-braking position together with the air piston 16 when the brake is released, the spindle 13 can rotate in the direction of moving the wedge cam 20 toward the braking position with respect to the wedge cam 20. At this time, the above-mentioned one-way clutch 65 provided between the fixing member 45 and the rotating member 51 allows the spindle 13 to rotate in the direction of moving the wedge cam 20 toward the braking position. As a result, the spindle 13 rotates with respect to the wedge cam 20 and the screw advances, so that the initial axial position of the wedge cam 20 with respect to the air piston 16 is adjusted, and the clearance is automatically adjusted against pad wear. Wedge. Therefore, the wedge cam type brake of this configuration can always operate the brake with a constant response time regardless of the amount of pad wear when the brake is operated.

Further, when the worn pad is replaced with a new pad, the fixing member 45 is released by the detent mechanism 61 to cancel the operation of the one-way clutch 65 described above. The detent mechanism 61 of the present embodiment is easily configured by the engaging recess 47 of the fixing member 45 and the engaging pin 55, and can easily switch between fixing and non-fixing of the fixing member 45.

That is, as shown in FIG. 7A, the fixing member 45 is housed in the pin accommodating portion 43 of the fixing base 41 and elastically urged to the engaging position by the coil spring 56. At the engaging position where the portion engages with the engaging recess 47, the protrusion 57a of the retaining portion 57 fixed to the rear end portion is immersed in the retracting recess 44 of the fixed base 41. Therefore, by pulling the engaging pin 55 downward against the urging force of the coil spring 56 and rotating it by a predetermined angle (for example, 90 degrees), the protrusion of the retaining 57 is projected as shown in FIG. 7B. The portion 57a is brought into contact with the lower surface of the fixed base 41. Then, the engaging pin 55 is in a state of being elastically urged to a non-engaging position where the tip end portion is separated from the engaging recess 47. Therefore, the fixing member 45 is released from being fixed by the detent mechanism 61, the operation of the one-way clutch 65 can be canceled, and the spindle 13 becomes rotatable.

Then, the axial position of the wedge cam 20 with respect to the air piston 16 can be returned to the position before the clearance adjustment only by rotating the spindle 13 in the direction in which the wedge cam 20 moves toward the non-braking position side. Therefore, it becomes easy to return the adjuster to return the axial position of the wedge cam 20 with respect to the spindle 13 before adjusting the clearance.

As shown in FIG. 8, the wedge cam type brake of the present embodiment has a through hole 53 formed in a direction intersecting the rotation axis direction of the rotating member 51 and a through hole 62 formed in the sliding plate 60. The inserted rotary jig 80 can abut on the other end of the spindle 13 to restrict the movement of the spindle 13 in the rotation axis direction to the braking position side (lower side in FIG. 8).
That is, when the spindle 13 is rotated by using the rotary jig 80 in order to return the axial position of the wedge cam 20 with respect to the air piston 16 before the clearance adjustment, the rotary jig 80 moves the rotation shaft of the spindle 13 to the braking position side. Regulate directional movement. Therefore, the spindle 13 rotated by the rotating jig 80 can surely screw the wedge cam 20 to the non-braking position side without being moved to the braking position side by the reaction force of the wedge cam 20 to be screwed. can. Therefore, it becomes easier to return the adjuster to return the axial position of the wedge cam 20 with respect to the spindle 13 before adjusting the clearance.

Although the embodiment of the present invention has been described above, as a mechanism that allows rotation in only one direction in order to transmit the rotational force of the spindle 13 only in the direction in which the wedge cam 20 is moved to the braking position side, a ratchet mechanism or the like is used. Various mechanisms can be used.

In addition, within the scope of the present invention, the shape of the wedge cam and the reversible screwing form with the spindle thereof (for example, a screw may be formed directly on the wedge cam without using the nut member 38). Various modifications such as the related configuration between the wedge cam and the base end of the brake arm can be considered. Further, the fluid pressure piston is not limited to the air piston driven by air, but may be a hydraulic piston driven by hydraulic pressure.
Further, in the above embodiment, the brakes for railway vehicles have been described, but it is clear that the present invention can be applied to automobiles such as heavy-duty trucks.

The present invention is not limited to the above-described embodiment, and can be appropriately modified, improved, and the like. In addition, the material, shape, size, number, arrangement location, etc. of each component in the above-described embodiment are arbitrary as long as the present invention can be achieved, and are not limited.

1 Body 2 Support 3 Brake arm 4 Brake arm shaft 5 Pad holder 6 Pad assembly 7 Link rod 10 Roller arm 13 Spindle 16 Air piston (fluid pressure piston)
17 Chamber spring (elastic member)
20 Wedge cam 22 Sleeve member (stationary part)
38 Nut member 41 Fixed base 43 Pin accommodating part 45 Fixing member 47 Engagement recess 51 Rotating member 55 Engaging pin 56 Coil spring 61 Anti-rotation mechanism 65 One-way clutch (mechanism that allows rotation in only one direction)

Claims (3)

The wedge cam in which the wedge cam is reversibly screwed is moved to a braking position along the rotation axis direction of the spindle by pressing and driving one end of the spindle in the rotation axis direction by a fluid pressure piston. This is a wedge cam type brake in which the base end of the brake arm is expanded by the cam action of the brake arm, and a pair of pad assemblies provided at the open ends of the brake arm is pressed from both sides of the brake rotor to perform a braking operation.
An elastic member that urges the fluid pressure piston to a non-braking position opposite to the driving direction,
A fixing member fixed to the stationary part on the brake body side via a detent mechanism,
A rotating member that cannot rotate relative to the other end of the spindle and is movably engaged in the direction of the axis of rotation.
A mechanism provided between the fixing member and the rotating member that allows rotation in only one direction in order to transmit the rotational force of the spindle only in the direction in which the wedge cam is moved toward the braking position side.
Wedge cam type brake equipped with. The detent mechanism
With the engaging recess formed in the fixing member,
An engaging pin provided in the stationary portion on the brake body side and capable of switching between an engaging position that engages with the engaging recess and a non-engaging position that disengages from the engaging recess.
The wedge cam type brake according to claim 1. The rotating jig inserted into the through hole formed in the direction intersecting the rotation axis direction of the rotating member is
The wedge cam type brake according to claim 1 or 2, wherein the wedge cam type brake can be brought into contact with the other end of the spindle to restrict the movement of the spindle in the rotation axis direction toward the braking position side.

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