JP6609172B2 - Brake device - Google Patents

Description

  The present invention relates to a brake device.

  Conventionally, the force of an actuator is applied to the force point of a pair of link arms that can rotate around a fulcrum, and the brake lining supported by the point of action of the link arm is brought into sliding contact with the brake disc to brake the rotation of the wheel. A brake device is used.

  In Patent Document 1, one end of a caliper lever is connected to each other, the other end is pivotally attached to a brake pad, and an eccentric transmission device provided at a fulcrum between both ends of the caliper lever is a caliper lever. A brake caliper unit that pivots is disclosed. The eccentric body transmission device has an eccentric pin that rotates in response to a force generated by a brake force generator, and rotates the caliper lever around one end by the rotation of the eccentric pin.

Japanese National Patent Publication No. 10-505038

  However, in the caliper brake unit of Patent Document 1, the circumferential tangential force that acts on the brake pad from the brake disk during braking when the brake pad slides on the brake disk acts on the eccentric pin of the eccentric body transmission device. Therefore, a large force is required to rotate the eccentric pin during braking, and it has been difficult to improve mechanical efficiency.

  The present invention has been made in view of the above-described problems, and an object thereof is to improve the mechanical efficiency of a brake device.

  In the first invention, a support portion between one end portion and the other end portion is rotatably supported with respect to the brake body, one end portions are connected by a connecting member, and each of the other end portions is in sliding contact with the brake disc. A pair of link arms that support a brake lining that applies frictional force, an actuator that is provided on the connecting member to move the output member forward and backward, a lever that rotates by the forward and backward movement of the output member, and one end portion of the pair of link arms. An eccentric cam provided on at least one of the rotating cams, and rotating about the rotation axis by the rotation of the lever. The eccentric cam is connected to the lever and rotated about the rotation axis, and is offset from the rotation axis. And an eccentric portion that is pivotally connected to one end portion of the link arm and that rotates in a circular arc shape around the rotation axis as the lever rotates.

  In the first invention, the link arm is supported such that the support portion between the one end portion and the other end portion is rotatable with respect to the brake body. And the eccentric cam which doubles the force transmitted by rotation of a lever and rotates a link arm by using a support part as a fulcrum is provided in the one end part of a link arm. Therefore, the circumferential tangential force that acts on the brake lining from the brake disc during braking of the brake device acts on the support and does not act on the eccentric cam.

  According to a second aspect of the present invention, the eccentric part is provided with a pair having a smaller diameter than that of the rotating part, and the rotating part is provided between the pair of eccentric parts with a lever connected so as not to be relatively rotatable.

  In the second invention, since the eccentric cam has a small diameter from the center toward both ends, it is easy to process and assemble.

  ADVANTAGE OF THE INVENTION According to this invention, the mechanical efficiency at the time of braking of a brake device can be improved.

1 is a plan view of a brake device according to an embodiment of the present invention. It is sectional drawing of the connection member periphery in a brake device. It is a figure explaining the positional relationship of the height direction of a lever and an adjuster.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, the configuration of the brake device 100 according to the embodiment of the present invention will be described with reference to FIGS. 1 to 3.

  The brake device 100 is mainly applied to a railway vehicle. The brake device 100 brakes the wheel 1 by sandwiching a brake disc 1 a that rotates together with the wheel 1. Specifically, as shown in FIG. 1, the brake device 100 sandwiches the brake disc 1 a from both sides with a pair of brake linings 2, and the friction force between the brake disc 1 a and the brake lining 2 causes the wheels 1 to move. Brakes rotation.

  The brake disc 1 a is formed on both front and back surfaces of the wheel 1 and rotates integrally with the wheel 1. Instead of the structure in which the brake disk 1a is formed integrally with the wheel 1, a separate brake disk 1a that rotates together with the wheel 1 may be provided.

  The brake lining 2 is opposed to the brake disk 1a with a predetermined interval (state shown in FIG. 1) when not braking. During braking, the brake lining 2 moves toward the brake disc 1a and is pressed against the brake disc 1a in parallel.

  The brake lining 2 includes a back plate portion 2a supported by the lining holding portion 3 of the brake device 100, and a friction member 2b that contacts the brake disc 1a during braking. The friction member 2b includes a plurality of segments and is fixed to the surface of the back plate portion 2a. The brake lining 2 brakes the rotation of the wheel 1 by the frictional force generated by the contact between the friction member 2b and the brake disc 1a.

  The lining holding part 3 has a dovetail groove (not shown) into which the back plate part 2a of the brake lining 2 is inserted. Anchor blocks 4 that are fixed to the lining holder 3 by a pair of anchor bolts 5 are respectively provided at the upper and lower ends of the lining holder 3. The anchor block 4 fixes the end of the back plate portion 2a of the brake lining 2 in the longitudinal direction (the direction perpendicular to the paper surface in FIG. 1). Thereby, the brake lining 2 inserted in the dovetail is held by the lining holding part 3.

  As shown in FIG. 1, the brake device 100 includes a pair of link arms on which a brake body 10 and a support portion 32 between one end portion 31 and the other end portion 33 are rotatably supported with respect to the brake body 10. 30, a connecting member 35 that connects the end portions 31 of the link arm 30, an actuator 20 that is provided on the connecting member 35 and advances and retracts the rod 21 as an output member, and the rod 21 that is rotatably connected to the rod 21. The link arm is provided on at least one of the lever 40 rotated by the advancement and retraction of the lever 40 and the one end 31 of the pair of link arms 30, and the force transmitted by the rotation of the lever 40 is boosted to support the support 32 as a fulcrum 30 to maintain a constant clearance between the brake unit 1 and the brake disc 1a when wear of the brake lining 2 progresses. It includes a Yasuta 60, a.

  The brake body 10 is supported by a carriage (not shown) when the brake device 100 is applied to a railway vehicle. The brake body 10 is supported by a vehicle body (not shown) when the brake device 100 is applied to a vehicle other than a railway vehicle.

  As shown in FIG. 2, the actuator 20 is a fluid pressure actuator that operates according to the pressure of a working fluid such as hydraulic pressure such as hydraulic pressure or air pressure. Actuator 20 operates based on a driver's braking operation, and moves rod 21 forward and backward. The actuator 20 may be other types such as a mechanical actuator that operates by rotation of an electric motor.

  The actuator 20 includes a diaphragm 22 as an elastic film that is elastically deformed by the pressure of the working fluid and moves the rod 21 back and forth, and a return spring 23 that biases the rod 21 against the pressure of the working fluid.

  Diaphragm 22 is sandwiched between case 20a and cover 20b, and defines a pressure chamber (not shown) between cover 20b. The diaphragm 22 is deformed when the working fluid is supplied to and discharged from the pressure chamber.

  The rod 21 advances and retreats with the deformation of the diaphragm 22. Specifically, when the working fluid is supplied to the pressure chamber, the rod 21 retreats in the direction in which the brake device 100 enters a braking state, and when the working fluid is discharged from the pressure chamber, the rod device 100 Enter in the direction of the non-braking state. The rod 21 has a flat portion 21 a that is in surface contact with the diaphragm 22.

  The rod 21 moves forward and backward with respect to the brake body 10 and can swing in a direction in which the brake lining 2 can move (left and right in FIG. 1). The center of the brake disc 1a is located on the extension line of the central axis along which the rod 21 reciprocates.

  The return spring 23 pushes the rod 21 back in the direction in which the brake device 100 is in a non-braking state. When the working fluid is supplied to the pressure chamber, and the force by which the working fluid in the pressure chamber pushes the rod 21 overcomes the urging force of the return spring 23, the rod 21 is pushed out in the direction in which the brake device 100 enters the braking state.

  The link arms 30 are respectively provided facing both surfaces of the brake disc 1a. One end portions 31 of the pair of link arms 30 are connected by a connecting member 35. The other end portion 33 of the link arm 30 supports the brake lining 2 slidably in contact with the brake disc 1a to apply a frictional force so as to be swingable. The link arm 30 has a pair of arm portions 30a provided at the top and bottom.

  As shown in FIG. 1, one end 31 of one link arm 30 is provided with a connecting shaft 31 a that penetrates and connects the connecting member 35 and the link arm 30. One end 31 of the other link arm 30 is connected through the connecting member 35, the link arm 30, and the pair of levers 40 so as to boost the force generated by the advancement and retraction of the rod 21 of the actuator 20. Is provided.

  Instead of this configuration, a booster unit 50 may be provided at one end 31 of one link arm 30 and one end 31 of the other link arm 30. In that case, each booster unit 50 can rotate one link arm 30 and the other link arm 30, respectively. The booster unit 50 will be described later in detail.

  The support portion 32 of the link arm 30 is provided with an arm shaft 32 a that penetrates and connects the link arm 30 and the brake body 10. The link arm 30 is rotatably supported by the brake body 10 by an arm shaft 32a. A circumferential tangential force acting on the brake lining 2 from the brake disc 1a during braking of the brake device 100 acts on the brake body 10 from the support portion 32 via the arm shaft 32a.

  The other end portion 33 of the link arm 30 is provided with a lining shaft 33 a that penetrates and connects the link arm 30 and the lining holding portion 3. The lining holding part 3 is rotatably supported by the link arm 30 by the lining shaft 33a. As a result, the brake lining 2 can swing with respect to the link arm 30 and can always abut against the brake disc 1a in parallel during braking.

  As shown in FIG. 2, the lever 40 transmits the force generated by the advancement / retraction of the rod 21 of the actuator 20 to the booster unit 50. One end 41 of the lever 40 is rotatably connected to the rod 21. The other end portion 42 of the lever 40 is connected to a large-diameter portion 52 as a rotating portion described later of the boosting unit 50. The lever 40 rotates between the rod 21 and the large diameter portion 52 when the rod 21 advances and retreats with respect to the brake body 10.

  The booster unit 50 includes an eccentric cam 51 that rotates about the rotation axis A <b> 1 as the lever 40 rotates.

  The eccentric cam 51 has a large-diameter portion 52 that is connected to the lever 40 and rotates about the rotation axis A 1, and a central axis A 2 that is offset from the rotation axis A 1. The eccentric cam 51 has a smaller diameter than the large-diameter portion 52. And an eccentric portion 53 that is rotatably connected to the one end portion 31 of the link arm 30. The center axis A2 of the eccentric cam 51 is provided such that the position with respect to the link arm 30 is the same position as the center axis of the connecting shaft 31a.

  The central axis of the large diameter portion 52 is the rotation axis A1 of the eccentric cam 51. The other end portion 42 of the lever 40 is connected to the large diameter portion 52 so as not to be relatively rotatable. Therefore, when the rod 21 moves back and forth and the lever 40 rotates, the large diameter portion 52 rotates around the rotation axis A1.

  The eccentric portions 53 are provided on both sides of the large diameter portion 52 in the axial direction. That is, the large diameter portion 52 is provided between the pair of eccentric portions 53. When the lever 40 rotates, the eccentric portion 53 rotates in an arc shape around the rotation axis A1 with the distance between the rotation axis A1 and the center axis A2 as a radius.

  The eccentric cam 51 has a large-diameter portion 52 at the center in the axial direction, and has eccentric portions 53 that are smaller in diameter than the large-diameter portion 52 at both ends thereof. Therefore, since the eccentric cam 51 has a small diameter from the center toward both ends, it is easy to process and assemble.

  The adjuster 60 includes a sleeve 61 that is rotatably provided around the central axis in the case 20a, and a rod 62 that is inserted into the sleeve 61. The rod 62 has a threaded portion 62 a that is threadedly engaged with the sleeve 61.

  When the wear of the brake lining 2 progresses beyond a specified amount, the sleeve 61 rotates through a link (not shown). As a result, the rod 62 moves out of the sleeve 61 by a size corresponding to the amount of wear of the brake lining 2. Thereby, the adjuster 60 always maintains the clearance between the brake disc 1a and the brake lining 2 at a constant size.

  As shown in FIG. 2, the adjuster 60 is provided as a single assembly together with the actuator 20 and the booster unit 50, so that the degree of freedom in design is high. Further, the adjuster 60 is provided so as to be shifted outside the movable range of the lever 40. Therefore, as shown in FIG. 3, the adjuster 60 and the lever 40 can be provided at the same height. Therefore, since it is not necessary to design the lever 40 to avoid other members, the booster unit 50 can be operated by the single lever 40.

  Next, the operation of the brake device 100 will be described.

  When the actuator 20 is actuated based on the driver's braking operation, the brake device 100 changes from the non-braking state (the state shown in FIG. 1) to the braking state.

  When the actuator 20 is actuated to supply the working fluid to the pressure chamber and the rod 21 is retracted, the lever 40 rotates. The force by which the actuator 20 retracts the rod 21 is transmitted to the large diameter portion 52 of the eccentric cam 51 through the lever 40.

  In the eccentric cam 51, the large-diameter portion 52 rotates around the rotation axis A1 by the force transmitted through the lever 40, and the eccentric portion 53 rotates in an arc shape around the rotation axis A1. It rotates in the counterclockwise direction in FIG. Thereby, since the eccentric part 53 rotates in the direction away from the rod 21, the one end parts 31 of a pair of link arms 30 move in the direction away from each other.

  Since the link arm 30 is rotatably supported by the brake body 10 by the support portion 32, when the one end portion 31 moves in a direction away from each other, the other end portion 33 moves in a direction close to each other. Therefore, the brake lining 2 moves toward the brake disc 1a and is pressed in contact with the brake disc 1a in parallel, so that the rotation of the wheel 1 is braked.

  At this time, as shown in FIG. 2, the eccentric cam 51 is moved from the rod 21 to the lever 21 by the lever ratio between the length L3 of the lever 40 and the distance L4 between the rotation axis A1 and the center axis A2 of the eccentric portion 53. The force transmitted through 40 is doubled by L3 / L4 and transmitted to the link arm 30. Therefore, a large braking force can be obtained without providing a large actuator. Therefore, the brake device 100 can be reduced in size and weight.

  As shown in FIG. 1, the link arm 30 is supported such that a support portion 32 between one end portion 31 and the other end portion 33 is rotatable with respect to the brake body 10. An eccentric cam 51 that rotates the link arm 30 by boosting the force transmitted to the rod 21 by the rotation of the lever 40 is provided at one end 31 of the link arm 30. Therefore, the circumferential tangential force that acts on the brake lining 2 from the brake disc 1 a during braking of the brake device 100 acts on the arm shaft 32 a of the support portion 32 and does not act on the eccentric cam 51. Therefore, since the frictional resistance when the eccentric cam 51 rotates does not increase, the mechanical efficiency during braking of the brake device 100 can be improved.

  As shown in FIG. 1, the force transmitted from the eccentric cam 51 to the one end portion 31 of the link arm 30 is the distance L1 between the one end portion 31 and the support portion 32, and the support portion 32 and the other end portion 33. It is boosted to L1 / L2 times by the lever ratio with the distance L2 between them. In the brake device 100, since the distance L1 and the distance L2 are approximately the same, the force that presses the brake lining 2 against the brake disc 1a is the force transmitted from the eccentric cam 51 to the one end 31 of the link arm 30. It is the same level of power.

  However, in the brake device 100, the force transmitted from the rod 21 of the actuator 20 via the lever 40 by the eccentric cam 51 is boosted at a large magnification. Therefore, even if the link arm 30 is shortened to reduce the distance L1 in order to reduce the size and weight of the brake device 100, a sufficiently large braking force can be obtained.

  In the brake device 100, the eccentric cam 51 is provided at the one end portion 31 of the link arm 30, so that the degree of freedom in designing the position of the arm shaft 32a of the support portion 32 is increased. Therefore, it is possible to arrange the arm shaft 32 a at a position facing the side surface of the wheel 1. Therefore, the distance L1 can be made larger than the distance L2, and the force boosted by the eccentric cam 51 can be further boosted to press the brake lining 2 against the brake disc 1a.

  The brake device 100 changes from the braking state to the non-braking state (the state shown in FIG. 1) when the actuator 20 operates in the direction opposite to that during braking based on the driver's braking release operation.

  When the actuator 20 is activated, the working fluid is discharged from the pressure chamber, and the rod 21 enters by the biasing force of the return spring 23, the lever 40 is pulled by the rod 21 and rotates. The force by which the actuator 20 causes the rod 21 to enter is transmitted to the large diameter portion 52 of the eccentric cam 51 through the lever 40.

  The eccentric cam 51 rotates in the other direction (clockwise in FIG. 1) when the eccentric portion 53 rotates in an arc shape around the rotation axis A1 by the force transmitted through the lever 40. Thereby, the one end part 31 of a pair of link arm 30 moves to the direction which adjoins mutually. Accordingly, the other end portions 33 of the pair of link arms 30 move in directions away from each other. As a result, the brake lining 2 is separated from the brake disc 1a, and the braking of the wheel 1 is released.

  At this time, if the amount of wear of the brake lining 2 advances beyond a specified amount, the adjuster 60 functions and the rod 62 retracts from the sleeve 61. Thereby, the clearance between the brake disc 1a and the brake lining 2 is always maintained at a constant size.

  According to the above embodiment, the following effects are obtained.

  The link arm 30 is supported such that a support portion 32 between the one end portion 31 and the other end portion 33 is rotatable with respect to the brake body 10. An eccentric cam 51 that rotates the link arm 30 by boosting the force transmitted to the rod 21 by the rotation of the lever 40 is provided at one end 31 of the link arm 30. Therefore, the circumferential tangential force that acts on the brake lining 2 from the brake disc 1 a during braking of the brake device 100 acts on the arm shaft 32 a of the support portion 32 and does not act on the eccentric cam 51. Therefore, since the frictional resistance when the eccentric cam 51 rotates does not increase, the mechanical efficiency during braking of the brake device 100 can be improved.

  Hereinafter, the configuration, operation, and effect of the embodiment of the present invention will be described together.

  In the present embodiment, a brake device 100 that clamps and brakes a brake disc 1a that rotates with a wheel 1 includes a brake body 10 supported by a vehicle body or a carriage, and one end 31 and the other end 33 with respect to the brake body 10. The support portions 32 are rotatably supported and are respectively provided on both sides of the brake disc 1a. One end portions 31 are connected to each other by a connecting member 35, and the other end portions 33 are connected to the brake disc 1a. A pair of link arms 30 that support the brake lining 2 that slides and applies a frictional force, an actuator 20 that is provided on the connecting member 35 and moves the rod 21 back and forth, and is pivotally connected to the rod 21 so that the rod 21 moves forward and backward. Provided at least one of the lever 40 and the one end 31 of the pair of link arms 30. An eccentric cam 51 that rotates about the rotation axis A1 by movement, and the eccentric cam 51 is offset from the rotation axis A1 with a large-diameter portion 52 that is connected to the lever 40 and rotates about the rotation axis A1. It has a central axis A2 at a position, is rotatably connected to one end portion 31 of the link arm 30, and has an eccentric portion 53 that rotates in an arc shape around the rotation axis A1 by the rotation of the lever 40.

  In this configuration, the link arm 30 is supported such that the support portion 32 between the one end portion 31 and the other end portion 33 is rotatable with respect to the brake body 10. An eccentric cam 51 that rotates the link arm 30 by boosting the force transmitted to the rod 21 by the rotation of the lever 40 is provided at one end 31 of the link arm 30. Therefore, the circumferential tangential force that acts on the brake lining 2 from the brake disc 1 a during braking of the brake device 100 acts on the arm shaft 32 a of the support portion 32 and does not act on the eccentric cam 51. Therefore, since the frictional resistance when the eccentric cam 51 rotates does not increase, the mechanical efficiency during braking of the brake device 100 can be improved.

  In the present embodiment, the eccentric portion 53 is formed in a pair having a smaller diameter than the large-diameter portion 52, and the large-diameter portion 52 is connected to the lever 40 such that the lever 40 cannot be relatively rotated. 53.

  In this configuration, the eccentric cam 51 has a small diameter from the center toward both ends, so that processing and assembly are easy.

  The embodiment of the present invention has been described above. However, the above embodiment only shows a part of application examples of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. Absent.

  For example, a needle bearing (not shown) as a rolling bearing may be provided on the outer periphery of the large diameter portion 52 in the eccentric cam 51. By providing the needle bearing on the outer periphery of the large-diameter portion 52, the eccentric cam 51 can be smoothly rotated when the actuator 20 is operated, so that the mechanical efficiency of the brake device 100 can be improved.

DESCRIPTION OF SYMBOLS 100 ... Brake device, 1 ... Wheel, 1a ... Brake disc, 2 ... Brake lining, 10 ... Brake body, 20 ... Actuator, 21 ... Rod (output member), 30 ... Link arm, 31 ... One end, 32 ... Supporting part, 33 ... Other end, 35 ... Connecting member, 40 ... Lever, 50 ... Booster unit, 51: Eccentric cam, 52: Large diameter part (rotating part), 53: Eccentric part

Claims (2)

A brake device that holds and brakes a brake disk that rotates with a wheel,
A brake body supported by the vehicle body or the carriage,
A support portion between the one end portion and the other end portion is rotatably supported with respect to the brake main body and is provided to face both surfaces of the brake disc, and the one end portions are connected by a connecting member, A pair of link arms each supporting the brake lining in which each of the other end portions is in sliding contact with the brake disc to apply a frictional force;
An actuator provided on the connecting member for moving the output member forward and backward;
A lever that is rotatably connected to the output member and rotates by the advancement and retraction of the output member;
An eccentric cam provided on at least one of the one end portions of the pair of link arms and rotating about a rotation axis by the rotation of the lever;
The eccentric cam is
A rotating part connected to the lever and rotating around the rotation axis;
An eccentric part having a central axis at a position offset from the rotational axis, rotatably connected to the one end of the link arm, and rotating in an arc around the rotational axis as the lever rotates. And a brake device. The eccentric part is formed in a small diameter compared to the rotating part and is provided as a pair,
2. The brake device according to claim 1, wherein the rotating part is provided between the pair of eccentric parts, and the lever is connected so as not to be relatively rotatable.

Images