JP2000095081A - Braking torque detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily compute correct braking torque from the output of a strain gauge. SOLUTION: In a disc brake device with a brake caliper 1 supported to a brake fitting part 20 by support pins 13, 14 accommodated in pinholes 11a, 12a of a pair of brackets 11, 12, a strain gauge is fitted into an area on the outer peripheral surface of the bracket 11 or 12 on the opposite side to the rotating direction of a disc rotor and in an area within a range of 90 deg. on both sides around the axes of the support pins 13, 14 from the passing points P1, P2 of tangents of circular arcs R1, R2 passing intersection points Q2 between the pinholes 11a, 12a and the circular arcs R1, R2 passing the center of the support pins 13, 14 respectively with the center axes of the support pins 14, 13 as the center. Braking torque is computed on the basis of output from the strain gauge.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake torque detecting device using a strain gauge, and more particularly to an improvement capable of easily detecting a correct brake torque.

[0002]

2. Description of the Related Art Disc brake devices as shown in FIGS. 1 and 2 are known as brake devices for railway vehicles.

[0003] A brake caliper 1 of the disc brake device is provided with a pair of arms 3A and 3B, and wraps around both side surfaces of a disc rotor 2 that rotates integrally with each wheel of a railway vehicle (not shown). These arms 3A, 3A
The ends of B are brake shoe support portions 4A and 4B that project on both sides (upper and lower sides in FIG. 1) of the brake caliper 1 in parallel with the disk rotor 2.

[0004] The disc rotor 2 is mounted on the brake shoe support 4A.
The brake shoe 5A extending in parallel with the side surface of the arm 2A of the vehicle is provided with torque receiving pins 6 on both sides of the brake shoe support 4A.
A, supported via 7A. Also, the brake shoe support 4B
, A brake shoe 5B extending parallel to the side surface of the disk rotor 2 on the side of the arm 2B is supported on both sides of the brake shoe support portion 5B via torque receiving pins 6B and 7B, respectively. In FIG. 1, only the torque receiving pins 6B and 7B are shown, and the torque receiving pin 6A on the same side as the torque receiving pin 6B (upper side in FIG. 1) and the same side as the torque receiving pin 7B (FIG. The torque receiving pin 6A on the lower side) is not shown.

[0005] A piston 8 is provided on the brake shoe supporting portion 4B, and the piston 8 is operated by receiving a supply of hydraulic pressure (brake pressure) through a hydraulic pressure inlet 9 provided in the arm 3B on the same side. The brake shoe 5B is pushed out toward the disk rotor 2. The brake pressure supplied to the piston 8 can be switched stepwise in units of notch (N).

The brake caliper 1 has a brake shoe support 4A,
4B, on the opposite side, a pair of brackets 11 extending diagonally on both sides (upper and lower sides in FIG. 2) of the brake caliper 1,
12 are provided. The ends of these brackets 11, 12 are cylindrical with pin holes 11a, 12b opening in a direction perpendicular to the disk rotor 2. The brake caliper 1 is provided with these pin holes 11a, 1
1b through the support pins 13 and 14 respectively penetrating
The vehicle is supported by a brake mounting portion 20 of the vehicle body. Note that the support pins 13 and 14 are
The brake caliper 1 is slidable in the axial directions a and 12b, and is movable in a direction perpendicular to the disk rotor 2.

With this configuration, when the brake shoe 5B is pressed against the disk rotor 2 by driving the piston 8,
The brake caliper 1 moves in a direction perpendicular to the disk rotor 2, and comes into contact with the brake shoes 5 </ b> A, 5 </ b> B so as to be sandwiched by the disk rotor 2. And at this time, the brake shoe 5
The frictional force acting between A, 5B and the disk rotor 2 becomes the brake torque.

[0008]

Incidentally, in recent years, a railway vehicle may be equipped with a brake control system such as an anti-lock brake system, so that it is necessary to detect a brake torque of a brake device. . Therefore, for example, Japanese Patent Application No. Hei 9-15465 filed by the present applicant attaches a strain gauge to the brake caliper 1 of the disc brake device and detects a brake torque based on the output of the strain gauge. Has been proposed.

However, in the brake torque detecting device using such a strain gauge, depending on the mounting position of the strain gauge, the strain of the brake caliper 1 that is not based on the brake torque itself may be detected.

More specifically, during braking, the brake caliper 1 applies a reaction force of the brake torque in either the upper or lower direction in FIG. 1 to the torque receiving pin 6A according to the direction in which the disk rotor 2 is rotating. , 7A, 6B, 7B
While the piston 8 is connected to the brakes 5A, 5B
Reaction force (arm 3
A, 3B). Therefore, for example, when the strain gauges are attached to the attachment positions X1, X2 (see FIG. 2) inside the curved portions at the base ends of the arms 3A, 3B, the distortion at these attachment positions X1, X2 is reduced by the brake shoe 5A. 5B is a large distortion due to the reaction force of the force pressed against the disk rotor 2, and does not directly reflect the brake torque.

As described above, if the output from the strain gauge has an effect other than the brake torque itself, the brake torque cannot be simply obtained from the output from the strain gauge. In order to remove the effects other than the brake torque itself from the output from the strain gauge and to detect the correct brake torque, it is necessary to experimentally correspond the output from the strain gauge to the correct brake torque in advance. Correction work is required.

The present invention has been made in view of such a problem. In a brake torque detecting device for detecting a brake torque of a disc brake device for a railway vehicle via a strain gauge attached to a brake caliper, the present invention relates to a brake torque detecting device. It is an object of the present invention to provide a device capable of easily calculating a correct brake torque from a strain gauge output by detecting a brake torque based on a distortion directly corresponding to the torque.

[0013]

According to a first aspect of the present invention, there is provided a disk rotor which rotates together with wheels, a pair of brakes disposed on both sides of the disk rotor, and a pair of brakes which are supported near a tip. A pair of arms provided on a brake caliper, pushing means for pushing at least one of the pair of brake shoes from the arm side to the disk rotor side, and a pair of brackets extending from opposite sides of the brake caliper from the pair of arms. And a support pin slidably received in a pin hole formed in the bracket in a direction perpendicular to the disk rotor and fixed to a mounting portion of a vehicle. The other of the outer peripheral surfaces of the one bracket extending to the opposite side to the moving direction with respect to the brake shoe Assuming that the brake caliper rotates around the support pin on the bracket side, one side of the extension line of the point where the support pin on one bracket abuts the inner peripheral surface of the pin hole on one bracket A strain gauge attached to a region within a predetermined angle range centered on the support pin on the bracket side, and brake torque calculating means for calculating a brake torque based on a detection signal from the strain gauge.

In the second invention, the predetermined angle range is:
An angle range of 90 degrees on both sides of the point on the extension line.

In the third invention, the strain gauge is attached to each of a pair of brackets, and the brake torque calculating means is attached to a bracket extending to a side opposite to a moving direction of the disk rotor with respect to the brake shoe. The brake torque is calculated based on the output from the strain gauge.

[0016]

According to the first and second aspects of the present invention, when at least one of the pair of brake shoes is pushed to the disk rotor side by the pushing means, the brake caliper moves in a direction perpendicular to the disk rotor, and The brake shoe contacts the disk rotor. The frictional force between the brake shoe and the disk rotor at this time becomes the brake torque, and the reaction force of the brake torque acts on the brake caliper. In this case, when it is assumed that the brake caliper rotates about the support pin of the bracket (the other bracket) extending in the direction of movement of the disc rotor with respect to the brake shoe, the strain gauge measures the movement direction of the disc rotor with respect to the brake shoe. Bracket that extends to the opposite side of the (one bracket)
Are attached to a region within a predetermined angle range (an angle range of 90 degrees in the second invention) on both sides from a point on the outer peripheral surface of the bracket on an extension of a point where the support pin contacts the inner peripheral surface of one bracket. Have been. Therefore, the position where the strain gauge is attached is a position where the support force from the support pin against the reaction force of the brake torque for rotating the brake caliper acts directly, and is structurally separated from the arm. As a result, the position is less affected by distortion in which the arm is pushed out by the reaction force from the pushing means. Therefore, the output of the strain gauge directly reflects the brake torque, and the brake torque calculating means can easily calculate an accurate brake torque based on the output of the strain gauge.

According to the third aspect of the present invention, the brake torque can be detected by the output from the strain gauge corresponding to the direction of rotation of the disk rotor regardless of the direction of rotation of the disk rotor. Even when the vehicle is traveling, the detection of the brake torque can be performed in the same manner.

[0018]

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

In each of the following embodiments, the entire structure of the disc brake device is the same as the conventional example shown in FIGS. 1 and 2, for example. Therefore, in the following description, based on the disc brake device shown in FIGS. 1 and 2, the description will be made focusing on the mounting position of the strain gauge which is a feature of the present invention, and the configuration of the disc brake device itself will be described. Do not repeat.

As shown in FIG. 1, in the brake torque detecting device according to the present embodiment, the strain gauge is connected to the bracket 11 or 1 on the opposite side to the rotation direction of the disk rotor 2.
2 from the point P1 or P2 on the outer peripheral surface of the bracket 11
Or, it is attached to an area within a range of 90 degrees on both sides along the outer circumferential direction of the 12 (with the axis of the support pins 13 and 14 as a center). Here, when the disk rotor 2 is rotating in the counterclockwise rotation direction in FIG. 1 (the disk rotor 2 moves from the torque receiving pins 6A, 6B side to the torque receiving pins 7A, 7B side with respect to the brake shoes 5A, 5B). When the disk rotor 2 is rotated), the bracket 11 is the bracket on the opposite side in the rotation direction of the disk rotor 2. On the other hand, when the disk rotor 2 is rotating in the clockwise rotation direction in FIG.
Are torque receiving pins 7A, 7B with respect to brake shoes 5A, 5B.
(When turning from the side to the torque receiving pins 6A and 6B)
, The bracket 12 is a bracket on the opposite side of the rotation direction of the disk rotor 2.

The present invention simplifies the analysis of the stress generated during braking, and reduces the points P1 and P2 (actually the support pins 13) on the outer peripheral surfaces of the brackets 11 and 12 so as to substantially fall within the allowable range. , 14) are determined based on the following hypothesis.

First, arcs R1 and R2 which are arcs centered on the center axes of the support pins 14 and 13 and pass through the centers of the support pins 13 and 14 are considered. And this arc R
Points where R1 and R2 intersect with the pin holes 11a and 11b are referred to as points Q1 and Q2, respectively. The point Q thus determined
When the brake caliper 1 is assumed to rotate around the support pins 14 and 13 in the rotation direction of the disk rotor 2 during braking, the support pins 13 and 14
a, 11b, and is a point pressed by the support pins 13, 14. The points P1 and P2 are determined as points where the tangents of the arcs R1 and R2 passing through the points Q1 and Q2 intersect with the outer peripheral surfaces of the brackets 11 and 12.

As described above, the points P1 and P2 on the outer peripheral surfaces of the brackets 11 and 12 on the opposite side of the rotation direction of the disk rotor 2 correspond to the support pins 13 and 14 having the pin holes 11a and 1a.
1b, which are on the extension of points Q1 and Q2 which are points in contact with the support pins 13 and 14 on the outer peripheral surfaces of the brackets 11 and 12 in a range of approximately 90 degrees on both sides from the points P1 and P2.
Causes tensile strain.

In this case, the brackets 11, 12
Extends to the opposite side of the arms 3A and 3B and
A and 3B are structurally separated from arms 3A and 3B
Is hardly distorted due to the effect of the force for pushing open.
For this reason, the distortion generated in the brackets 11 and 12 is caused by the supporting force from the supporting pins 13 and 14 (the force opposing the reaction force of the brake torque acting on the brake caliper 1 via the torque receiving pins 6A, 6B, 7A and 7B). 2) causes the brackets 11 and 12 to be stretched and distorted, directly reflecting the brake torque.

The strain gauges thus attached to the brackets 11 and 12 of the brake caliper 1 are incorporated in a predetermined bridge circuit, and the output of the bridge circuit becomes a strain gauge output. And since this strain gauge output is based on the tensile strain directly corresponding to the brake torque, an accurate brake torque can be easily calculated based on the strain gauge output,
The detection value from the brake torque detection device has a high accuracy that can be used in a brake control system such as an antilock brake system.

If strain gauges are attached to both the brackets 11 and 12 in accordance with the forward and reverse rotation directions of the disk rotor 2, even if the wheels rotate in either the forward or reverse direction (the vehicle The detection of the brake torque can be performed in the same manner when the vehicle is traveling in either the positive or negative direction.

[Brief description of the drawings]

FIG. 1 is a side view showing a disc brake device.

FIG. 2 is a front view of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Brake caliper 2 Disc rotor 3A 3B Arm 4A 4B Brake supporter 5A 5B Brake 6A 6B Torque receiving pin 7A 7B Torque receiving pin 8 Piston 9 Hydraulic introduction hole 11 Bracket 12 Bracket 13 Support pin 14 Support pin

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Izumi Hasegawa 38-8 Hikaricho, Kokubunji-shi, Tokyo Inside the Railway Technical Research Institute (72) Inventor Hideyuki Yasuda 38-8 Hikaricho, Kokubunji-shi, Tokyo 38 Within the Railway Technical Research Institute (72) Inventor Daisei Yamazaki 2-8 Hikarimachi, Kokubunji-shi, Tokyo 38 F-term within the Railway Technical Research Institute 3D046 AA07 BB28 HH52 3J058 BA60 DB18 FA21

Claims (3)

[Claims] 1. A disk rotor that rotates with wheels, a pair of brakes arranged on both sides of the disk rotor, and a pair of arms provided on a brake caliper so as to support these brakes near their distal ends. An extruding means for extruding at least one of the pair of brake shoes from the arm side to the disk rotor side; a pair of brackets extending from the opposite side of the brake caliper from the pair of arms; A support pin slidably housed in a pin hole formed in a direction perpendicular to the support hole and fixed to a mounting portion of the vehicle. The support pins on the other bracket side of the outer peripheral surface of one bracket Assuming that the brake caliper rotates as the center, the support pin on one bracket side is on both sides of the point on the extension line where the support pin on one bracket side contacts the inner peripheral surface of the pin hole on one bracket side. A strain gauge mounted in an area within a predetermined angular range centered on the brake gauge; and brake torque calculating means for calculating a brake torque based on a detection signal from the strain gauge. Detection device. 2. The brake torque detecting device according to claim 1, wherein the predetermined angle range is an angle range of 90 degrees on both sides of a point on the extension line. 3. The strain gauge attached to each of a pair of brackets, and the brake torque calculating means is attached to a bracket extending to a side opposite to a moving direction of the disk rotor with respect to the brake shoe. The brake torque detecting device according to claim 1 or 2, wherein the brake torque is calculated based on an output from the control unit.