JPH10252790A - Adjuster for disc brake device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adjuster to suppress the size in an axial direction of a rotor, eliminate a need to locate a load plate between a piston and a friction pad, and be suitable for reduction of size and weight. SOLUTION: An adjuster for a disc brake device is formed such that, in a disc brake device, an adjuster gear 30 to receive rotation of a spring member 38 for an input on an eccentric cam shaft 34, rotated integrally with an operation lever 36, through a one-way clutch mechanism 32 is provided between a pair of pistons 15 and 16 to press a friction pad 6 against a rotor 4, and transmission gears 27 and 28 to advance in an screwed-in state adjuster screws 21 and 22 fitted in the inner peripheries of the pistons 15 and 16 are engaged with the adjuster gear 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adjuster for adjusting a clearance between a rotor and a friction pad in a disk brake device, and more particularly, to an air adjuster that uses air pressure as a driving source of the friction pad during a braking operation. The present invention relates to an adjuster suitable for a drive type disk brake device.

[0002]

2. Description of the Related Art Heretofore, as an adjuster used in an air-driven disc brake device, a feed mechanism using a screw when rotated and driven behind a pair of pressure pieces brought into contact with a back plate of a friction pad. An adjusting spindle for pushing the pressure piece toward the rotor side via the control lever, an operating lever for rotating each adjusting spindle, a synchronizing device for synchronizing the rotation of each adjusting spindle, and a rotating torque acting on each adjusting spindle. A configuration incorporating a post-adjustment adjusting device has been proposed (see Japanese Patent Publication No. Hei 8-508080).

A pair of pistons are provided on the outer periphery and are provided so as to be movable in the axial direction of the rotor with their tips directed toward the rotor and press the friction pads, and a pair of pistons are provided on the outer periphery of each piston. A pair of sleeves are formed on the inner periphery of the female screw portion to be screwed with the male screw portion and are driven to rotate and reciprocate the piston along the rotor shaft. The sleeves are connected to the ends of each sleeve and rotate integrally with the sleeve. A pair of transmission gears, an adjuster gear provided between the pair of transmission gears so as to mesh with the pair of transmission gears, a camshaft that rotates by rotating the operation lever, and a camshaft of the camshaft. An adjuster having a transmission mechanism for rotating the adjuster gear by rotation has also been proposed (European Patent EP 0703379 A1).
reference).

[0004]

However, in the case of the former adjuster, since the various mechanisms including the adjusting spindle are connected in the axial direction of the rotor, the size is increased in the axial direction of the rotor, and the size is large in the axial direction of the rotor. There is a problem that it is necessary to secure a storage space, and it is difficult to mount it on a small vehicle or the like. Further, in the case of the latter adjuster, the outer diameter of the piston is reduced due to the structure in which the pair of pistons pressing the friction pad are screwed into the sleeve. Therefore, in order to stabilize the contact with the friction pad, it is necessary to interpose a load plate having a large contact area with the friction pad. Occurs. Then, due to the weight of the load plate, the return operation of the piston at the time of release of braking is not performed smoothly, and there is a possibility that dragging may occur.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems, and it is possible to suppress the dimension in the rotor axial direction, to easily mount it on a small vehicle or the like, and to press a friction pad. Since the diameter can be increased, the load plate does not need to be interposed between the piston and the friction pad, reducing the weight and, at the same time, causing the piston to return smoothly when braking is released, causing problems such as dragging. It is an object of the present invention to provide an adjuster for a disc brake device that can prevent the occurrence of a shock.

[0006]

In order to achieve the above object, an adjuster of a disk brake device according to the present invention comprises a rotor which rotates integrally with a wheel, a pair of friction pads arranged opposite to the rotor, and one of the friction pads. A drive mechanism accommodating portion serving as an accommodating portion of a piston for pressing a friction pad toward the rotor is provided at one end of a bridge portion straddling the rotor, and the other end side of the bridge portion has a back surface of the other friction pad. A disc brake device comprising: a caliper having a pressing claw portion; and a support fixed to a vehicle body and supporting the caliper so as to be movable in an axial direction of a rotor. Is adjusted to adjust the gap between the friction pad and the rotor by extruding the rotor pad to the rotor side, the headed cylinder having one end opened. And a pair of pistons mounted so as to be movable only in the axial direction of the rotor with the other end side closed toward the rotor side, and the distal end side slidably fitted to the inner periphery of the piston and the base end side. The adjuster has a pair of adjuster screws each having a screw portion, and a screw portion rotatably supported by the drive mechanism housing portion and screwed to an end of the adjuster screw. A pair of transmission gears for moving the screw forward and backward in the rotor axis direction, an adjuster gear provided between the pair of transmission gears so as to mesh with the pair of transmission gears, and rotatable on a center axis of the adjuster gear. A gear drive spring member interposed between the input wheel and the adjuster gear at the time of forward rotation of the input wheel provided with a concave portion for receiving a rotational torque on the outer periphery of the shaft portion loosely fitted to the shaft portion. Said input A one-way clutch mechanism for transmitting the rotational force of the wheel to the adjuster gear, an eccentric camshaft rotatably mounted between the pair of pistons with an axis directed radially of the rotor, and an end of the eccentric camshaft. An operating lever connected to the eccentric camshaft for rotating the eccentric camshaft, one end of which is locked to the outer periphery of the eccentric camshaft so as to rotate integrally with the eccentric camshaft, and the other end is on the side of the adjuster gear; And an input spring member that is inserted into a recess of the input wheel to transmit the rotation of the eccentric camshaft to the input wheel, and that the rotation of the input spring member is transmitted to the one-way clutch mechanism and the adjuster. Each piston is transmitted to the pair of transmission gears via a gear, and each adjuster screw is moved to the rotor shaft side by the rotation of the transmission gear. It is characterized in that it is sent to the rotor side.

According to the above arrangement, when the operating lever is rotated in the forward direction, the eccentric cam shaft is rotated in the forward direction integrally with the operating lever, and one end is connected to the eccentric cam shaft. The input spring member rotates the input wheel of the one-way clutch mechanism in the forward direction. Thereby, the adjuster gear connected to the input wheel via the gear driving spring member rotates. The rotation of the adjuster gear is achieved by pushing the adjuster screw screwed into the inner periphery of each piston to the rotor side via each transmission gear meshing with the adjuster gear, and pushing the adjuster screw causes each piston to move toward the rotor side. To move the friction pad with which these pistons are in contact to the rotor side.

In the above configuration, in order to move the piston to the rotor side, the components connected in the axial direction of the rotor include an adjuster screw and a transmission gear connected to an end of the adjuster screw. The eccentric camshaft, the one-way clutch mechanism, the adjuster gear, and the like for transmitting the rotation of the operation lever to the space between the pair of pistons do not affect the dimension in the rotor axial direction. That is, since there are few components connected in the rotor axis direction, the dimension in the rotor axis direction can be suppressed.

[0009] The piston for pressing the friction pad is
Since it fits on the outer periphery of the adjuster screw, the piston diameter can be maximized within the dimensional restrictions on the caliper. Since the diameter of the piston can be increased, the contact between the piston and the friction pad is stabilized, and it is not necessary to interpose a load plate between the piston and the friction pad to stabilize the contact.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. 1 to 6 show one embodiment of an adjuster of a disc brake device according to the present invention.
FIG. 1 is an exploded perspective view of an adjuster 1 according to one embodiment, FIG. 2 is a plan view of a part of a disk brake device 2 incorporating the adjuster 1, FIG. 3 is an enlarged view of a main part of FIG. 2 is a sectional view taken along line AA in FIG. 2, FIG. 5 is an enlarged view of a main part in FIG. 4, and FIG. 6 is a sectional view taken along line BB in FIG.

As shown in FIG. 2, a disc brake device 2 equipped with the adjuster 1 of this embodiment has a disk-shaped rotor 4 that rotates integrally with wheels, and a pair of disks 4 that are opposed to each other with the rotor 4 interposed therebetween. The friction pads 6 and 7 and a drive mechanism housing 11 c serving as a housing for a piston that pushes the rear surface of one of the friction pads 6 toward the rotor 4 are connected to the rotor 4.
Is provided at one end of a bridge portion 11a that straddles the other, and the other friction pad 7 is provided at the other end of the bridge portion 11a.
Caliper 11 equipped with claw portion 11b for pressing the rear surface of
A support 10 fixed to the vehicle body and supporting the caliper 11 so as to be movable in the axial direction of the rotor 4 (FIG. 4)
And at the time of normal braking (during service braking), the pair of friction pads 6, 7 are pressed against the rotor 4 by compressed air pressure to generate a predetermined braking force. It is. However, it goes without saying that the above-described adjuster 1 can also be mounted on a hydraulically-driven disk brake device that is widely used in passenger cars and the like.

Each of the friction pads 6, 7 described above functions as a lining portion 12 which is pressed against the surface of the rotor 4 to generate a predetermined frictional force, and is fixedly mounted on the back surface side of the lining portion 12 and serves as a mounting bracket or the like. And a back plate 13 to be formed.

In the adjuster 1 of one embodiment, one of the friction pads 6 is pushed out toward the rotor 4 by a pair of pistons 15 and 16 incorporated in the drive mechanism accommodating portion 11c of the caliper 11, and the friction pads 6 and The gap between the rotor 7 and the rotor 4 is adjusted.

Specifically, as shown in FIGS. 1 to 3, the adjuster 1 includes a piston support case 18 fixed to a drive mechanism accommodating portion 11c of the caliper 11, and a rotor shaft formed by the piston support case 18. A pair of adjusters each having a pair of pistons 15 and 16 movably supported in the direction, and a distal end slidably fitted to the inner circumference of each of the pistons 15 and 16 and a screw portion 19 formed at a base end. A pair of screws 21 and 22 and a screw portion 24 rotatably supported by the drive mechanism accommodating portion 11c via the piston support case 18 and screwed to the screw portion 19 of the adjuster screws 21 and 22; A transmission gear 27, 28; and an adjuster gear 30 provided between the pair of transmission gears 27, 28 so as to mesh with the pair of transmission gears 27, 28; A one-way clutch mechanism 32 mounted on the inner periphery of the just gear 30; an eccentric cam shaft 34 rotatably mounted between the pair of pistons 15 and 16 with its axis directed in the radial direction of the rotor 4; An operation lever 36 connected to an end of the shaft 34 for rotating the eccentric camshaft 34, and one end 38 a of which is connected to the outer periphery of the eccentric camshaft 34 so as to rotate integrally with the eccentric camshaft 34. And an input spring member 38 for transmitting the rotation of the eccentric camshaft 34 locked in the mating hole 34a to the one-way clutch mechanism 32.

The piston support case 18 has a pair of cylindrical portions 18a, 18a for accommodating the pistons 15, 16.
A shaft insertion hole 18b through which the eccentric camshaft 34 is inserted is formed therebetween. A gear support hole 18c that rotatably supports the adjuster gear 30 and the one-way clutch mechanism 32 is provided so as to pass through the center of the shaft insertion hole 18b.

The pair of pistons 15 and 16 have a headed cylindrical shape with one end opened, and the cylindrical portion 1 of the piston support case 18 has the closed other end facing the rotor 4.
8a is slidably fitted. Then, these pistons 15 and 16 move only in the rotor axis direction, and the rotation operation in the piston support case 18 is restricted.
An engagement groove 40 is formed on a front end surface of the friction pad 6 that contacts the back plate 13. The engagement grooves 40 are engaged with the projections formed on the back plate 13 so that each of the pistons 15, 1
6, the rotation is regulated.

The one-way clutch mechanism 32 includes an input wheel 65 provided with a concave portion 65b for receiving a rotational torque on an outer periphery of a shaft portion 65a rotatably loosely fitted on a center axis of the adjuster gear 30, and the input wheel 65. A gear driving spring member 66 interposed between the wheel 65 and the adjuster gear 30 is provided. The gear driving spring member 66 includes:
One end 66a is brought into contact with the step of the input wheel 65, and the other end 66b is connected to the step of the inner periphery of the adjuster gear 30 by a coil spring fitted to the outer periphery of the shaft 65a of the input wheel 65. When both ends 66a and 66b are compressed by the stepped portion of the input wheel 65 and the stepped portion of the adjuster gear 30 during the forward rotation of the input wheel 65, the rotation of the input wheel 65 is adjusted. 30. When the input wheel 65 rotates in the reverse direction, the step of the input wheel 65 is separated from the one end 66 a of the gear driving spring member 66, so that the rotation of the input wheel 65 is not transmitted to the adjuster gear 30.

The input spring member 38 is a coil spring fitted on the outer periphery of the eccentric camshaft 34 and has one end 38.
a is locked in an engagement hole 34 a on the outer periphery of the eccentric cam shaft 34, and the other end 38 b is connected to the adjuster gear 3.
It extends to the 0 side and is inserted into the concave portion 65b of the input wheel 65. When the eccentric camshaft 34 rotates, the input spring member 38 tries to rotate integrally with the eccentric camshaft 34, and at this time, the other end 38b comes into contact with one of the pair of protrusions 65c forming the recess 65b. The rotation of the eccentric camshaft 34 is transmitted to the input wheel 65. Also,
In a state in which the adjuster gear 30 cannot be rotated by the brake axial force, the input spring member 38 is elastically deformed,
It prevents breakage and does not follow the caliper rigidity,
Prevents overadjustment.

The width of the recess 65b is adjusted so that a gap s is ensured between the other end 38b of the input spring member 38 and the projecting piece 65c.
It is set larger than the outer diameter of b. Such a gap s becomes a backlash allowing relative rotation between the input spring member 38 and the input wheel 65, and the adjuster gear 30 is inadvertently driven to rotate by the fine rotation of the eccentric camshaft 34. It plays a role in preventing a drag phenomenon caused by overadjustment.

As shown in FIGS. 1 to 3, the adjuster screws 21 and 22 have a substantially cylindrical shape, and are threaded with the threaded portions (male threads) 24 of the transmission gears 27 and 28 described above. (Female screw) 19 is engraved on the inner periphery of the base end.
A flange 42 is formed on the outer peripheral portion of each of the adjuster screws 21 and 22 near the base end. The flange 42 comes into contact with the end surfaces of the pistons 15 and 16 and
The pistons 15 and 16 are pushed out toward the rotor 4 when the pistons 15 and 16 move toward the rotor 4 by receiving the rotation torque from the rotor 8. Also,
The flange portion 42 is provided on the cylindrical portion 18 of the piston support case 18.
An abutment on the protrusion protruding toward the inner diameter side of the base end of a through the seat plate 67 determines the initial position on the transmission gears 27 and 28 side.

When the transmission gears 27 and 28 are driven to rotate, the adjusting gears 21 and 22 which are screwed in advance and retreat in the axial direction of the rotor. An opening is provided at the center of each of the transmission gears 27 and 28 for inserting a return spring 44 that urges the pistons 15 and 16 away from the friction pad 6.

The return spring 44 is in contact with the cylindrical portion 46a inserted through the transmission gears 27 and 28 and the adjuster screws 21 and 22 and the end face of the transmission gears 27 and 28 projecting from the base end of the cylindrical portion 46a. It is housed in a spring receiving sleeve 46 having a positioning piece 46b. The return spring 44 housed in the spring receiving sleeve 46 is
The piston 1 is inserted through the center of the spring receiving sleeve 46.
Compression is performed by a washer 49 for a spring receiver provided on a bolt 48 screwed to each of the pistons 5 and 16, and a biasing force in a return direction is applied to the pistons 15 and 16. The positioning piece 46b of the spring receiving sleeve 46 is sandwiched and fixed between the body cover 50 screwed to the drive mechanism accommodating portion 11c from the outside of the spring receiving sleeve 46 and the transmission gears 27 and 28. .

Since the one-way clutch mechanism 32 is a friction type, the gap adjustment can be returned to the initial state by rotating the one-way clutch mechanism 32 at a clutching torque or more.

The adjuster 1 of one embodiment described above
Then, the operation lever 36 is rotated in the forward rotation direction (arrow (a) in FIG. 2).
3), the eccentric camshaft 34 rotates integrally with the operation lever 36, and the input spring member 38 mounted on the eccentric camshaft 34 rotates in the direction of arrow (b) in FIG. . By the rotation of the input spring member 38, the other end 38b of the input spring member 38 rotates the input wheel 65 of the one-way clutch mechanism 32 in the forward rotation direction. Thus, the adjuster gear 30 connected to the input wheel 65 via the gear driving spring member 66 rotates in the forward rotation direction, and the rotation of the adjuster gear 30 is transmitted to each of the transmissions meshing with the adjuster gear 30. The adjuster screws 21 and 22 fitted to the inner circumferences of the pistons 15 and 16 are sent out to the rotor side via the gears 27 and 28, and the pistons 15 and 16 are fed by the adjuster screws 21 and 22 to the rotor 4. Side, these pistons 15, 1
The friction pad 6 with which the friction pad 6 is in contact is moved toward the rotor 4 to reduce the gap between the rotor 4 and the friction pads 6 and 7.

In the adjuster 1 described above, in order to move the pistons 15 and 16 toward the rotor 4, the components connected in the axial direction of the rotor 4 are adjuster screws 21 and 2.
2 and an eccentric camshaft 3 for transmitting the rotation of the operating lever 36 to the transmission gears 27 and 28 using the transmission gears 27 and 28 connected to the ends of the adjuster screws 21 and 22.
4, input spring member 38 and one-way clutch mechanism 32
Are arranged in an empty space between the pair of pistons 15 and 16, and do not affect the dimension of the rotor 4 in the axial direction. That is, since there are few components connected in the direction of the rotor 4 axis, the dimension in the direction of the rotor 4 axis can be suppressed, the size can be reduced, and mounting on a small vehicle or the like becomes easy.

Since the pistons 15, 16 for pressing the friction pads 6, 7 are screwed to the outer circumferences of the adjuster screws 21, 22, the pair of pistons for pressing the friction pads are screwed into the sleeve. As compared with the conventional structure, the diameters of the pistons 15 and 16 can be maximized within the dimensional restrictions on the caliper 11.
Since the diameters of the pistons 15 and 16 can be increased, the contact between the pistons 15 and 16 and the friction pads 6 and 7 is stabilized.
There is no need to interpose a load plate between the friction pad 16 and the friction pads 6 and 7. Therefore, the weight can be reduced as compared with a structure having to be equipped with a load plate, and the piston 1 is released when the brake is released.
The return operations 5 and 16 can be smoothly performed to prevent inconveniences such as dragging.

When the operation lever 36 returns in the reverse direction, the eccentric camshaft 34 rotates in the reverse direction integrally with the operation lever 36. At this time, the end of the input spring member 38 on the eccentric camshaft 34 is
The input wheel 6 rotates in the reverse rotation direction together with the input wheel 6 after the gap s due to the backlash existing in the recess 65b is reduced.
In the reverse rotation acting on the input wheel 65, the gear driving spring member 66 interposed between the input wheel 65 and the adjuster gear 30 applies a load in the compression direction. No rotation is transmitted to the adjuster gear 30.

[0028]

In the adjuster of the disk brake device according to the present invention, the components connected in the rotor axial direction for moving the piston toward the rotor are an adjuster screw and a transmission gear connected to an end of the adjuster screw. About
An eccentric camshaft, a one-way clutch mechanism, an adjuster gear, and the like for transmitting the rotation of the operation lever to the transmission gear are arranged in an empty space between the pair of pistons, and do not affect the dimension in the rotor axial direction. That is, since there are few components connected in the rotor axis direction, the dimension in the rotor axis direction can be suppressed, the size can be reduced, and the mounting on a small vehicle or the like becomes easy. Further, since the piston that presses the friction pad fits around the outer circumference of the adjuster screw, the piston diameter can be maximized within the dimensional restrictions on the caliper. Since the diameter of the piston can be increased, the contact between the piston and the friction pad is stabilized, and it is not necessary to interpose a load plate between the piston and the friction pad to stabilize the contact. Therefore, it is possible to reduce the weight as compared with a structure that must be equipped with a load plate, and also to prevent the occurrence of inconvenience such as dragging by smoothing the return operation of the piston when releasing the brake. it can.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an embodiment of an adjuster of a disc brake device according to the present invention.

FIG. 2 is a cross-sectional plan view of a part of a disk brake device incorporating an adjuster according to an embodiment of the present invention.

FIG. 3 is an enlarged view of a main part of FIG. 2;

FIG. 4 is a sectional view taken along the line AA of FIG. 2;

FIG. 5 is an enlarged view of a main part of FIG.

FIG. 6 is a sectional view taken along the line BB of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Adjuster 2 Disc brake device 4 Rotor 6, 7 Friction pad 11 Caliper 11c Driving mechanism accommodation part 15, 16 Piston 18 Piston support case 19 Screw part 21, 22 Adjuster screw 24, 25 Screw part 27, 28 Transmission gear 30 Adjuster gear 32 One-way clutch mechanism 34 Eccentric camshaft 36 Operating lever 38 Input spring member 44 Return spring 46 Spring receiving sleeve 48 Bolt 54 Retainer 60 Gear press 65 Input wheel 65b Recess 66 Gear driving spring member

Claims (1)

[Claims] A driving mechanism accommodating portion serving as an accommodating portion for a piston that rotates integrally with a wheel, a pair of friction pads disposed opposite to the rotor, and a piston that presses one friction pad toward the rotor; A caliper that is provided at one end of a bridge portion that straddles the rotor and has a claw portion on the other end side of the bridge portion that presses the back surface of the other friction pad; A disc brake device comprising a support movably supported in a direction, wherein the pair of pistons pushes one friction pad toward a rotor to adjust a gap between the friction pad and the rotor. A headed cylindrical shape having one open end and a movable end provided only in the axial direction of the rotor with the other end closed toward the rotor. A pair of pistons, a pair of adjuster screws having a distal end side slidably fitted to the inner periphery of the piston and having a threaded portion formed on the proximal end side, and are rotatably supported by the drive mechanism housing. And a pair of transmission gears that have a threaded portion screwed to an end portion of the adjuster screw to move the adjuster screw forward and backward in the rotor axial direction when driven to rotate, and a pair of transmission gears that mesh with the pair of transmission gears. And an adjuster gear provided between the pair of transmission gears, and a concave portion for receiving a rotational torque on the outer periphery of a shaft portion rotatably loosely fitted on the center shaft of the adjuster gear at the time of forward rotation of the input wheel. A one-way clutch mechanism for transmitting the rotational force of the input wheel to the adjuster gear via a gear driving spring member interposed between the input wheel and the adjuster gear; An eccentric cam shaft rotatably mounted between the pair of pistons in the radial direction,
An operating lever connected to an end of the eccentric camshaft to rotate the eccentric camshaft; and one end locked to the outer periphery of the eccentric camshaft so as to rotate integrally with the eccentric camshaft. And an input spring member whose other end extends toward the adjuster gear and is inserted into a concave portion of the input wheel to transmit rotation of the eccentric camshaft to the input wheel. A disc transmitted to the pair of transmission gears via the one-way clutch mechanism and the adjuster gear, and each piston is sent out to the rotor side by the adjuster screw which moves to the rotor shaft side by rotation of the transmission gear. Adjuster for brake device.