JP2002221245A - Friction alarming unit for brake pad - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a friction alarming unit for a brake pad capable of installing a probe body in a back plate of the brake pad in a process with association with existing components without newly installing other components. SOLUTION: In a disk brake apparatus 10 having a friction detecting probe 50 electrically detecting a frictional limit of a frictional material 14 used for the brake pads 11 and 12, the friction alarming unit of the brake pads 11 and 12 is constituted so that an accommodating groove 15 is formed in both of an anti-rattling spring 40 and an outer peripheral edge of the back plate 13 of the brake pads 11 and 12 that are opposed each other, and that the probe body 51 of the friction detecting probe 50 is also inserted in the accommodating groove 15 while the probe body is limited to move to a direction parallel to the axis of a rotor, and that the escape of the probe body 51 toward an opening of the accommodating groove 15 is further prevented by the anti-rattling spring 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention electrically detects that the remaining thickness of the friction material of a brake pad that brakes the disk rotor when the brake is actuated has reached a wear limit. The present invention relates to a wear alarm device for a brake pad of a disc brake device, and more particularly to a structure for easily and reliably arranging a probe constituting the wear alarm device on the disc brake device.

[0002]

2. Description of the Related Art As a brake pad wear warning device, for example, Japanese Patent Application Laid-Open No.
No. 76 and Japanese Unexamined Patent Application Publication No. 5-248644. In the prior art described in the above publication, a columnar probe body of a wear detector that electrically detects the wear of a brake pad is fitted into a through hole (mounting hole) formed in a back plate of the brake pad, and protrudes therefrom. The U-shaped top of the insulated conductive wire is placed at the wear limit position of the friction material. When the columnar probe body is fitted in the through hole of the back plate, it allows movement in the direction toward the disk rotor, but restricts movement in the opposite direction. It is formed larger than the through hole and has a stepped shape. Further, a slit (retainer engaging groove) is formed at an axially intermediate portion of the small-diameter shaft portion, and the retainer is engaged with the slit, thereby restricting movement in the direction toward the disk rotor, thereby forming a through hole (retainer). Mounting hole). That is, the attachment of the columnar probe main body constituting the conventional wear alarm device to the brake pad is performed after the stepped columnar probe main body including the insulated conductor is inserted through the through hole of the back plate from the small diameter shaft side. This is performed by engaging a retainer with a slit formed in the small-diameter shaft portion.

[0003]

The above-mentioned conventional brake pad wear warning device has the following problems. <a> The columnar probe body of the wear detector that electrically detects the wear limit position must use a retainer to attach it to the back plate of the brake pad. Will increase.

<B> In addition to the step of fitting a columnar probe main body including a relatively long insulated conducting wire into a through hole (mounting hole) formed in a back plate, a slit (retainer engaging groove) formed in the columnar probe main body. And two steps of attaching the retainer to the backing plate, and it takes time and effort to attach the columnar probe body to the back plate.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to cooperate with an existing component to attach a probe body of a wear alarm device to a brake pad without adding any new component. To provide a brake pad wear alarm device which can be attached to the back plate of the brake pad in one step.

[0006]

Means for Solving the Problems As means for solving the above-mentioned problems, the invention according to claim 1 comprises a pair of brake pads for clamping the disk rotor by pressing the disk rotor from both sides in the axial direction, In a disc brake device including an anti-rattle spring that urges in a direction toward the rotor center and a probe that electrically detects a wear limit of a friction material of the brake pad, a brake pad facing the anti-rattle spring is provided. An accommodating groove is formed in the outer peripheral edge of the back plate, and the probe is fitted into the accommodating groove while restricting movement in a direction parallel to the rotor axis. A wear warning device for a brake pad, wherein detachment is prevented by the anti-rattle spring.

[0007] The invention according to claim 2 is the brake pad wear alarm device according to claim 1, wherein the anti-rattle spring is a leaf spring.

The invention according to claim 3 is the brake pad wear warning device according to claim 1, wherein the anti-rattle spring is a wire spring.

According to a fourth aspect of the present invention, a pair of brake pads for clamping the disk rotor from both sides in the axial direction for braking, and both ends of the brake pad in the circumferential direction of the rotor are slidable in a direction parallel to the rotor axis. And a torque receiving member provided with a bearing portion capable of supporting the rotor in the circumferential direction,
A disc brake device including a probe for electrically detecting a wear limit of a friction material of the brake pad, wherein a receiving groove is formed in an outer peripheral edge of a back plate of the brake pad opposed to a bearing of the torque receiving member; The probe is fitted into the receiving groove while restricting movement of the probe in a direction parallel to the rotor axis, and the torque receiving member prevents the probe from coming off in the opening direction of the receiving groove. A wear warning device for a brake pad.

According to a fifth aspect of the present invention, in the fourth aspect, the torque receiving member is spaced apart from an attachment portion attached to an immovable portion in opposition to one side surface of the disk rotor in a rotor circumferential direction. A brake pad wear alarm device, characterized in that the carrier has a rail portion on both ends of the brake pad.

According to a sixth aspect of the present invention, in the fourth aspect, the torque receiving member straddles the outer periphery of the pair of brake pads and the disk rotor, and is fixed to the one side surface of the disk rotor. An attachment portion attached to the, an actuator portion that presses and operates the brake pad,
A brake pad wear alarm device, characterized in that it is a caliper having a bearing portion opposed to both ends of the brake pad and spaced apart in a rotor circumferential direction.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the probe body is fitted into the housing groove of the back plate at an intermediate portion in a direction parallel to the rotor axis. A brake pad wear alarm device, wherein a non-rotatable groove is integrally formed.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an example of a brake pad wear warning device according to the present invention will be described in detail with reference to the drawings. First, a first embodiment of the present invention in which a brake pad wear warning device is applied to a floating disc brake device and a modified example thereof will be described with reference to FIGS.

<A> Structure of Disc Brake Apparatus The floating disc brake apparatus 10 includes a pair of brake pads 11 and 12 and a carrier 20 as a torque receiving member.
And a floating caliper 30 having an actuator portion and a reaction portion, which will be described later, as main components, including an anti-rattle spring 40 and a wear detector 50.
And so on. Hereinafter, the components described above will be individually described.

The pair of brake pads 11 and 12 are respectively
A friction material 14 is attached to the back plate 13 and integrally connected by tacking or the like. In the back plate 13 of the inner brake pad 11 in the present embodiment, a receiving groove 15 is formed by notching at the outer peripheral side of the rotor and at the edge of the central portion in the rotor circumferential direction. The accommodation groove 15 is desirably tapered so that the bottom is semicircular as shown in FIG. 2 and slightly expands toward the opening side, but is not limited thereto.
For example, it may be U-shaped.

The carrier 20, which is a torque receiving member, has a mounting portion 21 which is mounted on an immovable portion of the vehicle, facing one side surface of the disk rotor 60 which rotates integrally with the wheels, and has the disk rotor 60 interposed therebetween. Beam part 22 facing attachment part 21
And a pair of bridge portions 23, 23 which connect the two 21 and 22 in the circumferential direction of the rotor and connect them over the outer periphery of the rotor. An L-shaped rail portion 24 is formed on the attachment portion 21 and the bridge portion 23 on the side of the beam portion 22 so as to be spaced apart from each other in the circumferential direction of the rotor. , The two brake pads 11, 1
2 are erected so that both ends in the rotor circumferential direction are slidable in a direction parallel to the rotor axis and supported in the rotor circumferential direction.

The caliper 30 according to the present embodiment is of a split type, and includes a disk rotor 60 and a pair of brake pads 11,
12 is arranged so as to straddle the outer periphery. One of the caliper members 31 facing one side surface of the disk rotor 60 includes a pair of actuator portions 32, 32 arranged in parallel in the rotor circumferential direction, and a pair of pin slide mechanism portions 33 disposed on both outer portions thereof. , 33, the pistons 34, 34 (only one is shown in FIG. 1) of the actuator portions 32, 32 abut against the back plate 13 of the inner brake pad 11, respectively, and the pin slide mechanism portions 33, 33 are provided. Bottom hole 3
5, 35 (only one is shown in FIG. 1)
The guide pins 25, 25 (only one is shown in FIG. 1) erected from the mounting portion 21 are slidably fitted. Further, the other caliper member 36 faces the actuator portions 32, 32 and faces the outer brake pad 12.
And a pair of bridge portions 3 which are spaced apart in the circumferential direction of the rotor and cross over the outer periphery of the rotor.
8 and 38, and the bridge portions 38 and 38 are integrally attached to one of the caliper members 31 with four bolts 39. The structure in which the two caliper members 31 and 36 are integrally formed. Is also known. As is apparent from the above-described configuration, the caliper 30 includes a pair of pin slide mechanisms 33,
33 guides the carrier 20 in a direction parallel to the rotor axis, and a pair of brake pads 11, 1
2 are bridge portions 38, 38 of the other caliper member 36.
And the reaction part 37, and one caliper member 31
It is removable from the space defined by.

Anti-rattle spring 40 made of leaf spring
Extends along the outer periphery of the disk rotor 60 so as to cover the pair of brake pads 11 and 12, and elastically places the pair of brake pads 11 and 12 on the rail portions 24 and 24 of the carrier 20 which is a torque receiving member. It is a member for preventing backlash and dragging of the brake pads 11 and 12 by pressing the brake pads 11 and 12. As shown in FIG. 2, the anti-rattle spring 40 of the present embodiment has both ends in the rotor circumferential direction abutting against the inner surfaces of the inner bridge portions 23, 23 of the carrier 20, and the central portion resiliently contacts a probe body 51 described later. Or the protrusions 16, 16 of the brake pads 11, 12
The brake pads 11 and 12 are constantly biased toward the center of the rotor by elastic contact with the inner brake pad 11 (only the inner brake pad 11 is shown). Incidentally, the positioning of the anti-rattle spring 40 in the circumferential direction of the rotor is performed by fitting the projections 41, 41 projecting from both ends in the width direction (direction parallel to the rotor axis) into the accommodation grooves 15, 15 of the brake pads 11, 12. (Only the inner brake pad 11 side is shown). Further, the anti-rattle spring 40 is appropriately provided with a peephole through which the remaining allowance of the friction members 14 and 14 can be visually recognized, and a thinning for weight reduction.
The means for urging the brake pads 11 and 12 toward the center of the rotor (on the rail portion 24 of the carrier 20) is not limited to this. A pin is put between the caliper members 31 and 36, and the anti-rattle spring 4 is
0 and press both ends of the anti-rattle spring 40 to the back plates 13, 13 of the brake pads 11, 12.
May be elastically contacted, or the anti-rattle spring 40 made of a leaf spring can be easily changed to an anti-rattle spring 42 made of a wire spring as shown in FIG. The anti-rattle spring 42 shown in this plan view is made of a single wire, and the folded back pair of central crank-shaped portions 43, 43 is a portion that elastically presses both brake pads 11, 12. , The left and right ends 44, 45 are formed on the inner bridge portions 23, 2 of the carrier 20.
3. In short, both brake pads 1
It suffices if it has a function of constantly urging the rails 1 and 12 on the rails 24 and 24 of the carrier 20 and a function of preventing the wear detector 50 from coming off, which will be described later.

<B> Wear Alarm Device for Brake Pad The wear alarm device for the brake pad is a wear detector 50 for electrically detecting the wear limit position W of the friction material 14 shown in an enlarged view in FIG. It is composed of an alarm device (not shown) for warning that the brake pads 11 and 12 have been replaced. The wear detector 50 in this example is mounted on the inner brake pad 11, and as an example of the wear detector 50 composed of a probe body and an insulated conductor described later, the enlarged view of FIG. It will be described with reference to FIG.

<Probe Body> The probe body 51 is an integrally molded member such as a thermosetting resin that can be worn together with the friction material 14 without damaging the friction surface of the disk rotor 60. The probe body 51 has an outer shape in which one side of a substantially square is joined to a semicircle having the diameter of one side as a diameter, and the probe body 51 is provided with a receiving groove 15 of the inner brake pad 11 at an intermediate portion in the thickness direction. A U-shaped groove 52 having a V-shape close to the V-shape, and flanges 53 and 53 forming the U-shaped groove 52, and a gentle spherical portion 54 on a semicircular side on one plate surface side. The projection is formed. Here, if the taper angles of the two surfaces of the U-shaped groove 52 are set slightly larger than those of the accommodating groove 15 of the inner brake pad 11, it can be securely fixed only by pushing in. In the vicinity of the top of the spherical portion 54, two parallel through-holes 55, 55 penetrating in the plate thickness direction are formed so as to be spaced apart in the direction of the axis of symmetry of the outer shape of the probe main body 51. A semicircular top 56 is formed between the through holes 55.

<Insulated Conducting Wire> One insulated conducting wire 57 bent in a U-shape at the tip is a conductor 58 for electrically detecting a disconnection.
And an insulator 59 for protecting the conductor 58. The insulated conducting wire 57 is inserted into the through holes 55 from the spherical portion 54 side of the probe main body 51, and the ends thereof are connected to an alarm (not shown). In this example, the U-shaped inner surface of the insulated conductor 57 is
By contracting and fixing a contraction tube externally fitted to the insulated conducting wire 57 on the rear end side of the probe main body 51 in a state in which the insulated conducting wire 57 is in contact with the semicircular arc-shaped top portion 56, Although the position is shown with respect to the position, the position may be determined at the time of wiring. Further, the U-shaped portion of the insulated conducting wire 57 may be embedded in the probe main body 51, or may be electrically connected to the disk rotor 60 instead of a method of electrically detecting a disconnection. .

<C> Attachment Structure of Wear Detector As shown in FIGS. 2 and 4, the wear detector 50 pushes the probe body 51 into the accommodation groove 15 of the back plate 13 of the inner brake pad 11 so that the taper surface is reduced. The probe body 51 is fitted so as to bite, whereby the rotation of the probe body 51 is restricted by the fitting of the tapered surface. In addition, the flanges 53, 53 on both sides forming the U-shaped groove 52 are fitted so as to sandwich the back plate 13, so that falling off in a direction parallel to the rotor axis is restricted and the conductor 58 The inner surface of the U-shaped top 56 is set at the wear limit position W of the friction material 14.

Thus, the probe body 51 in this embodiment
Is prevented by the existing anti-rattle spring 40 or 42 from coming off in the opening direction of the accommodation groove 15 of the back plate 13. The projection 41 of the anti-rattle spring 40 and the central crank-shaped portion 43 of the anti-rattle spring 42
May be in elastic contact with the probe body 51,
Alternatively, they may be arranged with a slight gap.
Therefore, as is clear from the above description, the work of attaching the wear detector 50 to the inner brake pad 11 is only required to be fitted into the accommodation groove 15 of the pad 11,
Extremely simple.

<D> Brake operation Next, the brake operation in the above-described configuration will be briefly described. Now, the pistons 34, 34
When only one of them is shown in FIG. 1, the friction member 14 of the inner brake pad 11 frictionally engages with one side surface of the disk rotor 60, and the caliper 30 causes the pin slide mechanism 33, 33, and the reaction portion 37 of the other caliper member 36 presses the outer brake pad 12 to cause the friction material 1 to move backward.
4 is frictionally engaged with the other side of the disk rotor 60. The friction members 14 rotate integrally with the disk rotor 60 sandwiching the disk rotor 60, and the side surfaces of the back plates 13, 13 on the disk rotor 60 rotation direction side are supported by the rail portions 24, 24 of the carrier 20. To generate braking force. By repeating the braking operation for a long period of time, the friction material 14 of the inner brake pad 11 gradually wears, and finally the U
When the top of the character is broken, the driver is warned of replacement of the brake pads 11 and 12 by a warning light or a warning buzzer.

Next, a second embodiment in which the brake pad wear warning device according to the present invention is applied to another type of disc brake device will be described with reference to FIGS. 7 and 8. FIG. This embodiment is an embodiment in which the wear detector 50 is applied to a known opposed piston type disc brake device 17.
The same parts as those in the first embodiment will be described with the same reference numerals.

The caliper 70 is divided on the outer periphery of the disk rotor 60 and has a pair of caliper members 71 and 7.
The two bridge portions 73, 73 are combined in a face-to-face state, and are integrally formed by bolts 74 (four in this example) to form a downward U-shape. A pair of brake pads 1 facing both sides
It is disposed so as to straddle the outer circumferences of the rotors 1 and 12. Actuator portions 7 each having a built-in piston 75 that presses both brake pads 11 and 12 in a direction approaching each other are provided at opposing portions of both caliper members 71 and 72.
Bearings 77, 7 for supporting both ends of the brake pads 11, 12 in the circumferential direction of the rotor.
7 are formed respectively. Therefore, in this example, the caliper 70 functions as a torque receiving member that supports the peripheral edges of the brake pads 11 and 12 in the rotor circumferential direction. Also, both brake pads 11 and 12 are provided with two hanger pins 78 and between the pair of caliper members 71 and 72.
The two brake pads 11 and 12 have both ends in the rotor circumferential direction abutting against the lower surfaces of the hanger pins 78 and 78, and extend from the center thereof in a direction parallel to the rotor axis direction. The tongue piece 81 to be provided is the back plate 1
Anti-rattle spring 80 elastically contacting the outer edge of 3, 13
Thus, the rotor is biased in the direction toward the center of the rotor. Thus, the wear detector 50 according to the first embodiment described above is fitted into the accommodating groove 15 formed at the end of the inner brake pad 11 in the rotor circumferential direction, and the bearing 77 of the caliper member 71 is fitted.
Thus, the escape from the accommodation groove 15 is prevented. Further, the caliper member 71 on the inner brake pad 11 side is formed with an attachment portion 79 attached to an immobile portion of the vehicle body.
Brake operation and wear detector 5 in the above configuration
Since the operation of 0 will be easily understood,
The description is omitted.

The present invention is not limited to the first and second embodiments described above.
As the means for preventing the escape from zero, the one using the anti-rattle spring in the first embodiment and the one using the torque receiving member in the second embodiment can be applied by recombining each other. In other words, the torque detector (carrier 20) in the first embodiment prevents the wear detector 50 from coming off, and the anti-rattle spring 80 in the second embodiment prevents the wear detector 50 from coming off. Can easily be prevented. Further, it is obvious that the support structure of the brake pads 11 and 12 in the floating disc brake device 10 and the opposed piston disc brake device 17 is not limited to the above-described first and second embodiments. . Further, the wear detector 50 is mounted on the outer brake pad 12, or
A number of changes are possible, such as mounting on 1, 12 and the like.

[0028]

According to the present invention, as described above, the following effects can be obtained. <B> Utilizing existing anti-rattle springs and torque receiving members that are components of the disc brake device,
Since the wear detector fitted to the housing groove of the back plate of the brake pad is prevented from coming off in the opening direction of the housing groove, it is not necessary to add any new member as the means for preventing coming off.

<B> The step of attaching the wear detector to the back plate of the brake pad is only one step of fitting the wear detector into the accommodation groove of the back plate, and is inserted from the outer edge direction of the back plate. Therefore, the assembling operation is easy even in a probe main body including a relatively long insulated conducting wire.

[Brief description of the drawings]

FIG. 1 is a plan view showing a partial cross section of a floating disc brake device provided with a brake pad wear warning device according to a first embodiment of the present invention.

FIG. 2 is a front view showing a partial cross section of FIG. 1;

FIG. 3 is a rear view of FIG. 1;

FIG. 4 is a sectional view taken along line VI-VI of FIG. 1;

FIG. 5 is a plan view of a wire spring showing a modification of the first embodiment of the present invention.

6A and 6B are explanatory views of a wear detector of a wear alarm device, wherein FIG. 6A is a front view of a probe main body, and FIG.
(C) is a perspective view of the probe main body.

7A and 7B are cross-sectional views of a facing disc brake device provided with a brake pad wear warning device according to a second embodiment of the present invention, wherein FIG. 7A is a cross-sectional view taken along a brake center line when viewed from a rotor surface direction, and FIG. Is a BB cross-sectional view of FIG.

8 is a sectional view taken along line VIII-VIII of FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Floating type disk brake device 11, 12 Brake pad 13 Back plate 14 Friction material 15 Housing groove 16 Projection 17 Opposed piston type disk brake device 20 Carrier 21 Attachment part 22 Beam part 23 Bridge part 24 Rail part 25 Guide pin 30 Caliper DESCRIPTION OF SYMBOLS 31 Caliper member 32 Actuator part 33 Pin slide mechanism part 34 Piston 35 Bottom hole 36 Caliper member 37 Reaction part 38 Bridge part 39 Bolt 40 Anti rattle spring (made of leaf spring) 41 Projection 42 Anti rattle spring (made of wire spring) 43 Center Crank-shaped part 44 End part 45 End part 50 Wear detector 51 Probe main body 52 U-shaped groove 53 Flange part 54 Spherical part 55 Through hole 56 Top 57 Insulated conductor 58 Conductor 59 Insulator 60 Disk rotor 70 Carry 71,72 caliper member 73 bridge portion 74 bolt 75 the piston 76 the actuator 77 bearing 78 hanger pin 79 mounting portion 80 anti rattle spring (manufactured by leaf springs) 81 tongue portion W wear limit position

Claims (7)

[Claims] 1. A pair of brake pads for clamping a disk rotor from both sides in the axial direction to apply braking, an anti-rattle spring for urging the brake pads toward the center of the rotor, and a friction material for the brake pads. A disk brake device including a probe for electrically detecting a wear limit, wherein a housing groove is formed in an outer peripheral edge of a back plate of a brake pad opposed to the anti-rattle spring, and the probe is connected to a rotor axis line in the housing groove. A brake pad wear alarm, wherein the anti-rattle spring prevents the probe from coming off in the opening direction of the housing groove while the fitting is performed while restricting the movement in the parallel direction. apparatus. 2. An apparatus according to claim 1, wherein said anti-rattle spring is a leaf spring. 3. The brake pad wear warning device according to claim 1, wherein the anti-rattle spring is a wire spring. 4. A pair of brake pads for clamping the disk rotor by pressing the disk rotor from both sides in the axial direction, and guide both ends of the brake pads in the rotor circumferential direction slidably in a direction parallel to the rotor axis. In a disc brake device including a torque receiving member provided with a bearing portion that can be supported in a circumferential direction, and a probe that electrically detects a wear limit of a friction material of the brake pad, the disk braking device faces the bearing portion of the torque receiving member. An accommodating groove is formed in the outer peripheral edge of the back plate of the brake pad, and the probe is fitted into the accommodating groove while restricting movement of the probe in a direction parallel to the rotor axis, and an opening direction of the accommodating groove of the probe. A brake pad wear alarm device, wherein the brake pad is prevented from coming off by the torque receiving member. 5. The brake pad according to claim 4, wherein the torque receiving member is attached to an immovable portion facing one side of the disk rotor, and both ends of the brake pad are spaced apart in a circumferential direction of the rotor. A wear warning device for a brake pad, characterized in that the carrier is provided with a rail part on which a part is erected. 6. The mounting according to claim 4, wherein the torque receiving member straddles the pair of brake pads and an outer periphery of a disk rotor, and is attached to an immovable portion facing one side surface of the disk rotor. A brake pad wear alarm, characterized in that the caliper includes a mounting portion, an actuator portion that presses the brake pad, and a bearing portion that is spaced apart in a circumferential direction of the rotor and faces both ends of the brake pad. apparatus. 7. The probe body according to claim 1, wherein a non-rotatable groove fitted into the housing groove of the back plate is provided at an intermediate portion of the probe body in a direction parallel to a rotor axis. A wear warning device for a brake pad, which is integrally formed.