JP2009133462A - Disk brake mechanism for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disk brake mechanism for a vehicle, which securely maintains booster function by being prevented an M-link from being reversely turned even if excessive abrasion of a pad is produced while adopting the M-link booster mechanism from which the booster mechanism efficient even if it has small stroke, is provided. <P>SOLUTION: The disk brake mechanism is configured so as to compose the M-link by pivoting 7A about a basic end of brake arms 3, 3 each other end of a pair of opposed links 7, 7 of which one end is pivoted with a rod 14 at predetermined angle, and to pivot each oscillating shaft 15 of the brake arms 3 with oscillation end of a pair of adjustment links 6, 6 pivoted with a body and oscillating. If the excessive abrasion of the pad occurs, it properly adjusts distance between the oscillating shafts 15, 15 of the brake arm and prevents the brake arm 3 from being excessively oscillated even though the pad is worn because of adjusting the distance between them by interposing an appropriate adjustment mechanism between the pair of adjustment links 6, 6 which pivot each of the oscillating shaft 15 of the brake arm 3. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle disc brake mechanism that swings a pair of opposing brake arms via a rod that is axially moved by an actuator, and presses a disc rotor on a pad disposed at a swing end of the brake arms. .

In a disc brake device used in a vehicle, particularly in an air disc brake for a railway vehicle, the relative movement between a sprung to which a brake is attached and an unsprung to which a disc rotor is attached is large. In addition, a lever-type brake is known that is easily adapted to a large relative movement and is connected to a link that has a large braking force (see, for example, Patent Documents 1 and 2 below).
JP 2006-315422 A (refer to the gazette abstract) Japanese Patent Application Laid-Open No. 58-146728 (refer to the appended claims)

  The patent document will be briefly described. The conventional railway vehicle disc brake device disclosed in Patent Document 1 shown in FIG. 8 as Conventional Example 1 includes two brake heads 107 and 107 each having a brake pad attached to clamp the disc D. The caliper levers 106 and 106 and an actuator 114 including a movable rod 115 driven in at least one of the advancing direction and the retracting direction are provided, and the disc brake device 101 is pivotally connected to the movable rod 115. A rotation transmission arm 116 and a telescopic shaft 110 engaged with the rotation transmission arm 116 are provided. The screw body 113 is pushed outward by the screw mechanism due to the push-out rotation of the rotation transmission arm 116 as the actuator 114 advances, and the caliper levers 106 and 106 are swung around the support pin 105, so that the brake head 107, 107 clamps the disk D and a braking operation is performed. When the brake pad is worn, the notch end portion of the cam plate 119 comes into contact with the gap adjusting rod 121 fixed to the base body due to the excessive stroke of the rotation transmitting arm 116, the worm gear 117 rotates, and the gap adjusting gear 118 rotates. Then, automatic gap adjustment is made.

  Further, the disc brake disclosed in Patent Document 2 shown in FIG. 9 as the conventional example 2 has a pair of operating links 211 connected by connecting pins 215 with an intersecting angle as shown in FIG. 9B. 212, a pair of levers 201 and 202 that are pin-coupled (213 and 214) to both sides of the pair of operating links 211 and 212, respectively, and an intermediate portion of the pair of levers 201 and 202 fixed to the vehicle body 203 In a disc brake having a bracket 205 to be worn, and an inner pad 208 and an outer pad 207 which are attached to the tip portions of the pair of levers 201 and 202 and clamp the disc 218 which rotates together with the wheels, the bracket 205 and the lever 201, The buffer member 219, 220 (FIG. 9A) is interposed on the receiving surface of the braking torque with 202. It is an feature.

  With these configurations, in the first conventional example disclosed in FIG. 8, the advance operation of the movable rod 115 is converted into the extension operation of the telescopic shaft 110 via the rotation transmission arm 116, and the force is The force was increased and transmitted to the caliper levers 106 and 106. Moreover, since the rotation transmission arm 116 constituting the boost conversion mechanism is provided with a gap adjusting mechanism including a cam plate 119, a notch, a worm gear 117, a gap adjusting gear 118, etc., the gap between the disk D and the brake pad is reduced. A compact configuration of the highly functional disc brake device 101 that can be automatically adjusted can be provided. Further, in the second conventional example disclosed in FIG. 9, a brake is provided by a booster mechanism for co-operation of a pair of operating links 211 and 212 and a pair of levers 201 and 202 that constitute a so-called M link. Even with a small stroke of the cable 216, a large braking force can be obtained by the pair of levers 201 and 202.

  However, in these conventional examples, in the first conventional example, the air used in the actuator 114 has a normal pressure of about 600 to 700 kPa, so that it is suitable for a railway vehicle to obtain a large braking force. Are designed to increase the cross-sectional area of the air chamber and increase the link ratio of the brake arm. For this reason, it is necessary to secure a large mounting space for the brake mechanism, and there is a possibility that the bogie for the railway vehicle is also increased in size. In the second conventional example, a large braking force can be obtained by employing the M link, but the pair of levers 201 and 202 are pivotally supported by the arms 205a and 205b of one bracket 205. Therefore, in order to suppress the impact sound during braking, it is necessary to interpose the buffer members 219 and 220 on the receiving surface of the braking torque between the bracket 205 and the levers 201 and 202, and the structure becomes complicated. When the inner pad 208 and the outer pad 207 are worn, there is a risk that the pair of operation links 211 and 212 constituting the M link will reverse due to the excessive stroke of the brake cable 216 and the booster mechanism will not function. There was this.

  Therefore, the present invention solves the problems of the conventional vehicle disc brake mechanism and uses an M link booster mechanism that can provide an efficient booster mechanism even with a small stroke, while causing excessive wear of the pad. Even so, an object of the present invention is to provide a vehicular disc brake mechanism in which the reverse of the M link is prevented and the boosting function can be reliably maintained.

  For this reason, the present invention provides a vehicle disc brake that swings a pair of opposing brake arms via a rod that is axially moved by an actuator, and presses a disc rotor on a pad disposed at the swing end of these brake arms. In the mechanism, each other end of a pair of opposing links whose one ends are pivotally supported by the rod at a predetermined angle are pivotally supported on the base end of the brake arm, and the links and the brake arm have an M-shape. And the swinging shafts of the brake arms are pivotally supported on the swinging ends of a pair of adjustment links that are pivotally supported by the body. Further, the present invention is characterized in that an automatic gap adjusting mechanism is provided between the swinging portions of the pair of adjustment links so as to shorten and adjust the distance between the adjustment links in conjunction with the excessive stroke of the rod. To do. Further, according to the present invention, the automatic gap adjustment mechanism includes an adjuster arm that swings by the axial movement of the rod, an adjuster rod that moves in conjunction with the adjuster arm, an adjuster screw that ratchets with the adjuster rod, The adjuster screw is composed of a pair of adjuster nuts screwed from both sides in the axial direction and pivotally supported by the pair of adjustment links, and these are used as means for solving the problems.

  According to the present invention, a disk brake for a vehicle that swings a pair of opposing brake arms via a rod that is axially moved by an actuator, and presses a pad disposed at a swing end of the brake arms against a disk rotor. In the mechanism, each other end of a pair of opposing links whose one ends are pivotally supported by the rod at a predetermined angle are pivotally supported on the base end of the brake arm, and the links and the brake arm have an M-shape. In addition, an M link booster mechanism is adopted by pivotally supporting each swinging shaft of the brake arm on the swinging end of each of the pair of adjustment links that are swingably supported by the body. A pair of adjustments that support each swinging shaft of the brake arm when excessive wear of the pad occurs. Since it is possible to adjust the distance between them by interposing an appropriate adjustment mechanism between the brakes, the distance between each swinging axis of the brake arm can be adjusted properly, even if the pad wears The M link is not reversed by the excessive swing of the brake arm, that is, the excessive stroke of the rod, and the boosting function is not lost.

  In addition, when an automatic gap adjustment mechanism is provided between the swinging portions of the pair of adjustment links to shorten and adjust the distance between the adjustment links in conjunction with the excessive stroke of the rod, When the rod generates an excessive stroke, the distance between the pair of adjustment links, that is, the distance between the swing shafts of the pair of brake arms is automatically adjusted to be shortened. The excessive swing of the rod, that is, the excessive stroke of the rod is suppressed and adjusted so that the M link is not reversed and the boosting function is not lost. In addition, stroke adjustment is performed by adjusting the spacing on the swing shaft side of the brake arm constituting the M link without adjusting the stroke side of the rod. The variation of the mechanism is also minimal. Further, the automatic gap adjusting mechanism includes an adjuster arm that swings by the axial movement of the rod, an adjuster rod that moves in conjunction with the adjuster arm, an adjuster screw that engages with the adjuster rod and a ratchet, and the adjuster screw. When it is composed of a pair of adjuster nuts that are screwed in from both sides in the axial direction and are respectively supported by the pair of adjusting links, there are few due to a combination of mechanical mechanisms such as an adjuster arm, an adjuster rod, and an adjuster screw. A large adjustment stroke can be mechanically generated even for the stroke of the rod, and a reliable and large adjustment force can be automatically obtained.

  DESCRIPTION OF EMBODIMENTS Preferred embodiments for implementing a vehicle disc brake mechanism according to the present invention will be described below with reference to the drawings. As shown in FIG. 1, the basic configuration of the vehicle disc brake mechanism of the present invention is to swing a pair of opposing brake arms 3 and 3 via a rod 14 that is axially moved by an air chamber 8 that is an actuator. In the vehicular disc brake mechanism in which the pads 16 and 16 disposed at the swing end portions of the brake arms 3 and 3 are pressed against the disc rotor 18, one end of the rod 14 is pivotally supported at a predetermined angle 7B. The other ends of the pair of opposed links 7 and 7 are pivotally supported 7A and 7A on the base ends of the brake arms 3 and 3, so that the links 7 and 7 and the brake arms 3 and 3 have an M shape. And the pivoting shafts 15 and 15 of the brake arms 3 and 3 are pivotally supported by the body 1 and supported by the swinging end portions of the pair of adjustment links 6 and 6 that can swing. Characterized in that was.

  The vehicle disc brake mechanism of the present invention will be described in detail below. As shown in FIGS. 2 and 4, the caliper body 1 is fixed to a support 2 supported by a vehicle body (not shown) via bolts or the like via a link 4 that prevents rotation (prevents accompanying rotation to the disk rotor during braking). The As shown in FIG. 1A, a main brake air chamber 8 is disposed in the caliper body 1. Preferably, the power source is fluid pressure such as air pressure (either positive pressure or negative pressure is possible). The air chamber 8 is urged in the brake releasing direction by the restoring force of the coil spring disposed inside. The brake operation is performed by compressing these coil springs with a positive pressure disposed on the opposite side through the diaphragm or by introducing a negative pressure on the coil spring side to compress the coil springs. A pair of opposing brake arms 3, 3 are swung via a rod 14 that is axially moved by an air chamber 8, and pads 16, 16 disposed at the rocking ends of the brake arms 3, 3 are attached to a disk rotor 18. A braking force is obtained by pressing. A large number of pads 16, 16 are attached to the inside of the pad holder 5 that is pivotally supported by the holder shaft 17 at the swinging end portion of the brake arm 3.

  In the present invention, the air chamber 8 operates perpendicular to the rotational axis of the disk rotor 18. That is, the rod 14 that is axially moved in accordance with the expansion and contraction of the air chamber 8 is disposed perpendicular to the rotation axis of the disk rotor 18. One end of a pair of links 7 and 7 (hereinafter referred to as “M link”) is pivoted by a rod shaft support portion 7B with a predetermined link angle (angle formed on the rod advance side of the rod 14 and link 7) at the intermediate portion of the rod 14. Be supported. The other end portions of the pair of opposing M links 7 and 7 are pivotally supported on the base end portions of the brake arms 3 and 3 by arm shaft support portions 7A and 7A. The M links 7 and 7 and the brake arms 3 and 3 are arranged so as to have an M shape. As shown in FIG. 1B, the swinging shafts 15 and 15 of the brake arms 3 and 3 are a pair of swingable shafts that are pivotally supported on the caliper body 1 by adjusting link shaft support portions 13 and 13, respectively. It is pivotally supported on the swing end of each adjustment link 6, 6.

Since it is configured in this way, with respect to the M link 7 having a predetermined link angle θ as a boosting mechanism, the pressing force of the rod 14 by the air chamber 8 is FC, and the base end of the brake arm 3 (arm shaft end) If the force FL is about 7A)

2FL = FC · tanθ ··· (Formula 1)

Therefore, since FL = (1/2) · FC · tan θ, the force FL pushing the base end portion of the brake arm 3 as a lever in the orthogonal direction is proportional to the link angle θ, and the smaller θ, the smaller the force FC. Even if the rod 14 is pushed with a small stroke, the magnification of the booster mechanism is increased. When the brake arm 3 receives an outward force FL at a base end portion that is a shaft fulcrum with the M link 7, that is, the arm shaft support portion 7A, the base end portion expands with the swing shaft 15 as a swing center. The pad 16 disposed on the rocking end via the pad holder 5 is pressed against the side surface of the disk rotor 18 to perform a braking operation.

  As shown in FIG. 1 (B), each swing shaft 15 of the brake arm 3 is swung at the end of a pair of adjustment links 6 that can be swung supported by the caliper body 1 by an adjustment link shaft support portion 13. Is pivotally supported. With this configuration, when excessive wear occurs on the pad 16, an appropriate adjustment mechanism is interposed between the pair of adjustment links 6 and 6 that pivotally support the swing shafts 15 of the brake arm 3. Allowing you to adjust the distance between them. As this adjusting mechanism, an automatic gap adjusting mechanism described later is preferably employed, but an appropriate manual adjusting mechanism in the form of a turnbuckle may be used. In short, the rocking shaft 15 of the brake arm 3 is not pivotally supported by the caliper body 1, but is pivotally supported by the rocking end of the adjustment link 6 that is pivotally supported by the caliper body 1. Thus, the swing shaft 15 of the brake arm 3 is configured to be movable relative to the caliper body 1 to be adjusted.

  As shown in FIG. 2A, the base end portion of the brake arm 3 is formed in a bifurcated shape, and the other end portion of the M link 7 is pivotally supported by the arm shaft support portion 7A. The intermediate portion of the brake arm 3 is pivotally supported by the swing shaft 15 on the swing end portion of the inverted link-shaped adjustment link 6 that is pivotally supported on the caliper body 1 by the adjustment link shaft support portion 13. The pad holder 5 is pivotally supported on the swinging end portion of the brake arm 3 by two holder shafts 17 so as to swing freely. FIG. 3A shows the assembled state viewed from the inside (CC cross section in FIG. 1B). 3A shows an automatic gap adjusting mechanism (9, 10: to be precise, the adjuster arm 12, the adjuster rod 11, etc. are included) of the adjuster arm 12, the adjuster rod 11 and the adjuster screw 9 for adjusting. The state in the cross section including the interlocking mechanism such as the ratchet teeth 9A is clearly shown. FIG. 3B is a cross-sectional view of the disc brake mechanism at a position disengaged from the air chamber 8, and is opposite to the cross-sectional position where the automatic gap adjusting mechanism (9, 10) in FIG. is there.

  FIG. 2B is a cross-sectional view taken along the line BB of FIG. 2A, and is a cross-sectional view at a position where the automatic gap adjusting mechanism (9, 10) is disposed. Therefore, it is understood that the automatic gap adjusting mechanism (9, 10) is in a position displaced away from the rocking surface on which the M links 7, 7 are rocked by the rod 14. The automatic gap adjusting mechanism (9, 10) includes an adjuster screw 9 having ratchet teeth 9A at the center and engraved reverse screws on both sides thereof, and is screwed from both sides of the adjuster screw 9 in the axial direction. The adjustment link 6 is composed of a pair of cylindrical adjuster nuts 10 that are pivotally supported by the adjustment link shaft support portion 10A. Therefore, by rotating the adjuster screw 9, the pair of cylindrical adjuster nuts 10 and 10 screwed from both sides of the adjuster screw 9 can be brought close to each other or separated from each other. As a result, the adjustment link 6 can be adjusted and swung around the adjustment link shaft support 13 in the caliper body 1 so that the rocking shaft of the brake arm 3 can be moved closer to and away from the adjustment link shaft support 13.

  As shown in FIG. 3 (A), one end of a pair of M links 7 and 7 is pivotally supported by an arm pivotal support portion 7A at an intermediate portion of the round rod-like rod 14 whose tip side is formed in a plate shape. An adjuster arm 12 having a base end supported by the caliper body 1 at a fulcrum 12A is fitted into the vicinity of the distal end of the rod 14 to form an adjuster arm shaft support 7C. This state can also be understood from the plan view of the disc brake mechanism shown in FIG. The base end of the adjuster rod 11 is connected to the swinging end of the adjuster arm 12. Although details will be described later, a tooth portion that meshes with the ratchet teeth 9 </ b> A of the adjustment task screw 9 is formed at the lower end, that is, the tip portion of the adjuster rod 11. FIG. 4 is a plan view of the disc brake mechanism, in which the caliper body 1 is connected to the support 2 via the rotation restraining link 4, the shaft arm is supported by the brake arm 3 and the M links 7, 7, and the rod 14 and the adjuster arm. 12 and the connection form of the adjuster arm 12 and the adjuster rod 11 are clearly understood.

  The operation of the automatic gap adjustment mechanism will be described with reference to the schematic diagrams of FIGS. FIG. 5 is a schematic diagram before and after the start of the braking operation of the disc brake mechanism of the present invention. FIG. 5A shows the start of braking operation (initial), and FIG. 5B shows the time of braking. Air is introduced into the air chamber 8 and the rod 14 is pushed out by upward force (FC). And a component force ((1/2) · FC · tan θ) to the outside (left and right in the drawing) is applied to 7A at the other end via a pair of M links 7 and 7 supported by the arm shaft support 7B. Join. As a result, the upper ends of the pair of brake arms 3 and 3 are expanded with the swing shaft 15 as the center, and as shown in FIG. 5 (B), the pads 16 and 16 disposed at the swing ends are arranged. Thus, braking is started by pressing the side surface of the disk rotor 18.

  During a normal state in which the pad 16 is not worn, as shown in FIGS. 6 (A) and 6 (B), an adjuster rod that moves up and down due to the swing of the adjuster arm 12 interlocked with the axial motion of the rod 14. 11 is in sliding contact with the ratchet teeth 9A of the adjustment task screw 9 in the automatic clearance adjustment mechanism. FIG. 6B shows the initial position of the braking operation of the swing shaft 15, where the solid line position indicates a normal state where the pad 16 is not worn, and the dotted line position indicates a state where the pad 16 is worn.

  FIG. 7 shows an adjustment state of the position of the swing shaft 15 in the brake arm 3 by the automatic gap adjustment mechanism when the wear of the pad 16 progresses. As the wear of the pad 16 progresses, the upward stroke of the rod 14 becomes excessive. Accordingly, as shown in FIGS. 7A and 7C, the adjuster rod 1 is sufficiently pulled upward so that the tooth portion 11A at the lower end of the adjuster rod 11 is engaged with the ratchet teeth 9A of the adjuster screw 9. It reaches to. When the rod 14 is retracted (moved downward) by the restoring spring in the air chamber 8 and returned to the original position, the tooth portion 11A at the lower end of the adjuster rod 11 rotates the ratchet teeth 9A in one direction (arrow direction). Move. As a result, as shown in FIG. 7B, the adjuster screw 9 is rotated and the adjuster nuts 10 and 10 screwed to both sides thereof are moved in proximity to each other, and the adjustment links 6 and 10 are adjusted via the adjustment link shaft support portions 10A. 6 is swung in the vicinity of each adjustment link shaft support portion 13 as a center. Thus, the swing shaft 15 of the brake arm 3 is adjusted to the position of the dotted line.

  Thus, even if the wear of the pad 16 progresses and the stroke of the rod 14 becomes excessive, the distance between the pair of adjustment links 6 and 6, that is, between the swing shafts 15 and 15 of the pair of brake arms automatically. Therefore, the excessive swing of the brake arm, that is, the excessive stroke of the rod is suppressed and adjusted so that the excessive stroke of the rod is corrected, and the M link is not reversed and the boosting function is not lost. In addition, stroke adjustment is performed by adjusting the spacing on the swing shaft side of the brake arm constituting the M link without adjusting the stroke side of the rod. The variation of the mechanism can be minimized.

  Although the embodiments of the present invention have been described above, within the scope of the present invention, the shape and type of the support and caliper body, the shape and type of the air chamber as the actuator (both positive pressure type and negative pressure type) (Diaphragm type, piston type, etc. can also be adopted), rod shape, type and its connection with air chamber, brake arm shape, type, M link shape, type and Connection form of M link to brake arm and rod, link angle of M link, pad shape, form and form of pivot support to brake arm (vertical swing form, etc.), form of adjustment link, form and form to caliper body Automatic support adjustment mechanism interposed between the swinging part of the pair of adjustment links Shape, type, interlocking mode of rod and automatic adjustment mechanism (of the embodiment, adjuster arm that swings by the axial movement of the rod, adjuster rod that pivots in conjunction with the adjuster arm, and engagement of the adjuster rod and ratchet An adjuster screw that is screwed from both sides in the axial direction of the adjuster screw and the pair of adjustment links, and an adjuster rod that interlocks with the diaphragm of the air chamber and an adjuster screw that has ratchet teeth. Other suitable interlocking mechanisms may be adopted as appropriate. The specifications described in the examples are merely examples in all respects and should not be interpreted in a limited manner.

1 shows a vehicle disc brake mechanism according to the present invention. FIG. 1A is a cross-sectional view at the center of an air chamber including an M link portion, and is a cross-sectional view taken along the line A-A in FIG. It is a partial cross section figure which shows the state in which the rocking | fluctuation shaft of the brake arm was pivotally supported by the rocking | fluctuation end part of the adjustment link. 2A is an overall view of a disc brake mechanism including a brake arm as viewed from the axial direction of the disc rotor, and FIG. 2B is a cross-sectional view of a plane including a central portion of the automatic gap adjusting mechanism. It is BB sectional drawing of A). 3A is a cross-sectional view of the assembled state of the disc brake mechanism from the inside, and is a cross-sectional view taken along the line CC of FIG. 1B. FIG. 3B is a disc brake at a position removed from the air chamber. It is sectional drawing of a mechanism. 2 is a plan view of the disc brake mechanism. FIG. FIG. 3 is a schematic view before and after the start of the braking operation of the disc brake mechanism of the present invention. FIG. 6A is a schematic diagram showing a swinging mode of an adjuster arm that is linked to the axial movement of the rod, and FIG. 6B is a schematic diagram showing an initial position of a braking operation of the swinging shaft of the brake arm. . FIG. 6 is a schematic diagram showing an adjustment state of the position of the swing axis of the brake arm by the automatic gap adjustment mechanism when wear of the pad 16 proceeds. It is explanatory drawing of the disc brake apparatus for rail vehicles of a 1st prior art example. It is explanatory drawing of the M link type disc brake of a 2nd prior art example.

Explanation of symbols

1 Caliper body 2 Support 3 Brake arm 5 Pad holder 6 Adjustment link 7 M link 7A Arm shaft support 7B Rod shaft support 7C Adjuster arm shaft support 8 Actuator (air chamber, etc.)
13 Adjustment link shaft support portion 14 Rod 15 Brake arm swing shaft 16 Pad 17 Holder shaft 18 Disc rotor

Claims (3)

In a vehicular brake mechanism that swings a pair of opposing brake arms via a rod that is axially moved by an actuator and presses a pad disposed on the swing end of the brake arm against a disc rotor, The other end portions of a pair of opposing links whose one end portions are pivotally supported at an angle are pivotally supported on the base end portion of the brake arm, and the links and the brake arm are arranged so as to exhibit an M shape, A disc brake mechanism for a vehicle, wherein each swing shaft of a brake arm is pivotally supported on a swing end portion of each of a pair of adjustment links that are swingably supported by the body. 2. The automatic gap adjustment mechanism is provided between the swinging portions of the pair of adjustment links so as to shorten and adjust the distance between the adjustment links in conjunction with an excessive stroke of the rod. The disc brake mechanism for vehicles as described. The automatic gap adjusting mechanism includes an adjuster arm that swings by the axial movement of the rod, an adjuster rod that moves in conjunction with the adjuster arm, an adjuster screw that ratchets with the adjuster rod, and an axis of the adjuster screw The disk brake mechanism for a vehicle according to claim 2, comprising a pair of adjuster nuts screwed from both sides in the direction and pivotally supported by the pair of adjustment links.

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