JP4580243B2 - Pressure detector mounting structure - Google Patents

Description

  The present invention relates to a mounting structure of a pressing force detector for detecting a pressing force by a pressing member.

2. Description of the Related Art Recently, in a braking device for a vehicle, a technique for detecting a brake pedal depression amount by a driver and controlling a rotation of a motor (electric motor) based on the detected value to obtain a desired braking force, so-called brake-by.・ Wire technology is being developed. In this type of braking device, it is necessary to accurately detect the pressing force of the disk pad against the disk rotor. For example, Patent Document 1 proposes a mounting structure of a pressing force detector (load sensor) that detects a pressing force on a claw portion of a housing that fixes one disk pad.
JP 2004-183694 A (Claim 1, FIG. 1)

  However, in the above-described conventional pressing force detector mounting structure, since the pressing force detector is provided so as to contact the disk pad, heat and vibration generated due to friction between the disk pad and the disk rotor during braking. There is a risk that these may become noise and reliability during detection may be impaired. Moreover, it is necessary to provide an expensive sensor excellent in heat and vibration.

  The present invention solves the above-described conventional problems, and an object thereof is to provide a pressing force detector mounting structure that can be manufactured at low cost without impairing reliability during detection.

The present invention is a mounting structure of a pressing force detector in a braking device that generates a braking force on the disk rotor by sandwiching the disk rotor between a pair of disk pads, the piston pressing one of the disk pads, An actuator for moving the piston in the axial direction, a bottomed cylindrical main body that movably supports the one disk pad and the piston via the actuator, and the other disk pad fixed to the main body. and a housing portion having a L-shaped section of the claw portion for supporting, the main body portion of the housing portion, said housing recess only pressing force detector is fixed is formed, the said pressing force detector so as to cover in the tool body and arranged to abut the housing recess, the pressing force detector, the disk package by the piston Wherein characterized in that the reaction force acting on the housing portion by the pressing force to the disk rotor and so as to indirectly detect the force based on the strain of the housing portion of the.

  According to the present invention, the pressing force detector can be installed at a position away from the pressed member. Thereby, in the case where noise is generated between the pressing member and the pressed member, it is possible to relax the environmental resistance condition of the detection element provided in the pressing force detector.

When applied as a braking device for a vehicle as this, it is possible to reduce the influence of frictional heat and vibration between the disc rotor and the brake pad during braking.

  ADVANTAGE OF THE INVENTION According to this invention, it can use suitably for the braking device for vehicles, Comprising: A low-cost and highly accurate detection is attained.

  FIG. 1 is a cross-sectional view showing a mounting structure of a pressing force detector according to the present embodiment, FIG. 2 is a cross-sectional view showing an internal structure of the pressing force detector, and FIG. 3 shows an example of mounting the pressing force detector on a housing portion. Sectional drawing and FIG. 4 are operation | movement diagrams in the attachment structure of the pressing force detector of this embodiment. In the following description, the mounting structure of the pressing force detector will be described by taking the vehicle braking device 1 as an example.

  As shown in FIG. 1, the braking device 1 is a so-called floating type braking device, and includes a housing portion 10, a pair of disk pads (pressing members) 20, 21, an actuator 40, and a pressing force detector S1. I have.

  The housing part 10 includes a main body part 11 and a claw part 15. In the main body 11, a bottomed cylindrical case 12 and a cylindrical case 13 having both ends open are fitted via an O-ring 14. The claw portion 15 has an L-shaped cross section, and is fixed to the case 12 of the main body portion 11 via a screw (not shown) or the like. The tip 15a of the claw 15 has a surface facing the X direction, and the surface is separated from the main body 11 by a predetermined distance. In addition, although the housing part 10 of this embodiment is comprised by three said members, it is not limited to this, The case 12 and the case 13 are integrally formed, and the main-body part 11 and the nail | claw part 15 And may be integrally formed.

  The disk pads 20 and 21 are constituted by friction members 20a and 21a and fixed plates 20b and 21b to which the friction members 20a and 21a are fixed, and are respectively supported on the housing part 10 side. One disk pad 20 is provided on the main body 11 side, and the other disk pad 21 is provided on the tip 15 a of the claw 15. An outer peripheral surface of a disc-shaped disc rotor R fixed to a wheel (not shown) is located in a gap formed between the disc pads 20 and 21. Although not shown in the drawings, the disk pads 20 and 21 of the present embodiment have an elongated shape in which the shape when viewed from the X direction is curved in a direction along the outer peripheral surface of the disk rotor R.

  The actuator 40 is a so-called ball screw, and includes a cylindrical rotary member 42, a rod-like advance / retreat member 43 inserted through the rotary member 42, and a plurality of these provided between the rotary member 42 and the advance / retreat member 43. Ball 44. Further, in this actuator 40, a helical groove-shaped female screw portion 42 a is formed on the inner peripheral surface of the rotating member 42, and a helical groove-shaped male screw portion 43 a is formed on the outer peripheral surface of the advance / retreat member 43. There is a mechanism in which a plurality of balls 44 circulate between the portion 43a. The actuator 40 is configured by fixing a piston 41 to the tip of an advance / retreat member 43. Further, the rotating member 42 is rotatably supported on the housing part 10 side, and the rotating member 42 rotates, so that the advance / retreat member 43 moves linearly in the X direction together with the piston 41. Yes. Moreover, the circumference | surroundings of the piston 41 and the end of the said main-body part 11 are covered with the elastic member 30, and the inside of the main-body part 11 is sealed.

  The actuator 40 is connected to a power transmission mechanism 50 including a motor (electric motor) M and a pair of bevel gears 51 and 52. The bevel gear 51 is formed in a ring shape, and is fixed to the base end of the rotating member 42 with the advance / retreat member 43 inserted therethrough. The bevel gear 52 is meshed with the bevel gear 51. The bevel gear 52 is fixed to a shaft 53 that is rotatably supported by the case 12 of the housing portion 10, and the power of the motor M is transmitted to the shaft 53. When the bevel gear 52 is rotated by the power of the motor M, the bevel gear 51 rotates integrally with the rotating member 42, and the rotating member 42 is supported so as not to advance and retract, so the advance / retreat member 43 operates in the X direction.

  As shown in FIG. 2, the pressing force detector S <b> 1 includes a base 60, a sphere 70, a cover 80, and a strain detection element 90. The base 60 is formed in a cylindrical shape, and a hole 61 penetrating in the vertical direction in the figure is formed at the center thereof. A spherical receiving portion 62 is formed in the upper edge portion of the hole 61, and the spherical body 70 is supported by the receiving portion 62. The base 60 is not particularly limited as long as it is a material that can be deformed and deformed. For example, the base 60 is selected from ceramic, stainless steel, aluminum, and the like. The spherical body 70 is formed of stainless steel, high carbon chrome steel, or the like, and is preferably a true sphere. By making the shape a true sphere, the load can be dispersed well. In addition, on the upper surface of the base 60, strain detection elements 90 are arranged at intervals of 90 degrees around the sphere 70 (only two places are shown in FIG. 2). Although not shown, the strain detecting element 90 is configured by laminating an insulating layer, a strain gauge, a wiring, a coating layer, and the like. The number of strain detection elements 90 to be installed is not limited to four, but may be five or more or less than four.

  In the pressing force detector S1, a cover 80 that covers the base 60 is provided. The cover 80 is made of stainless steel or the like, and a through hole 81 having a diameter smaller than the diameter r of the sphere 70 is formed at the center of the upper surface thereof. Thereby, when the cover 80 is installed on the base 60, the upper part of the sphere 70 protrudes from the through hole 81, and the height position of the through hole 81 is positioned above the equator line of the sphere 70. ing. Accordingly, it is possible to reliably prevent the sphere 70 from falling off the base 60 simply by idling while contacting the receiving portion 62.

  The pressing force detector S1 described above is not limited to the one in this embodiment, and may be a sensor in which the sphere 70 and the cover 80 are not provided. Further, the element for detecting the strain mounted on the pressing force detector S1 is not particularly limited as long as it can detect the strain of the base 60. The strain gauge type, capacitance type, piezoelectric type, A magnetostrictive type, a gyro type, etc. can be selected.

  In the braking device 1, the pressing force detector S1 is provided at a position indicated by a broken line in FIG. That is, as shown in FIG. 3, a housing recess 13 a to which the pressing force detector S <b> 1 is fixed is formed in the case 13 (main body portion 11) of the housing portion 10. In this embodiment, it arrange | positions so that the spherical body 70 which is an input part provided in pressing force detector S1 may contact | abut to the surface 13a1 which faces the X2 direction of the storage recessed part 13a. The other pressing force detectors S1 are similarly arranged in a plane perpendicular to the X direction with respect to the housing portion 10. The braking device 1 is supported so as to be movable in the X (X1-X2) direction with respect to a bracket BK1 fixed to a non-rotating vehicle body (for example, a knuckle).

  As shown in FIG. 1, the braking device 1 is provided with a control unit 100. The control unit 100 is connected to each pressing force detector S1 and the motor M, acquires a detection signal from each pressing force detector S1, and the rotation direction and amount of rotation of the motor M are controlled based on the detection signal. The For example, a signal based on the stroke of the brake pedal of the vehicle is transmitted to the control unit 100, and the pressing force of the piston 41 against the disc pad 20 is controlled while acquiring the detection signal of the pressing force detector S1.

Next, the effect | action in the attachment structure of this embodiment is demonstrated with reference to FIG.
When the rotating member 42 of the actuator 40 rotates in a predetermined direction via the bevel gears 51 and 52 by the power of the motor M, the advance / retreat member 43 moves in the X1 direction together with the piston 41. The disk pad 20 presses the surface on the X2 side of the disk rotor R by the moving force of the piston 41 in the X1 direction. When the piston 41 presses the disk rotor R in the X direction with the pressing force F1, the reaction force F1 having the same force as the pressing force F1 acts on the actuator 40 in the X2 direction. When the reaction force F1 acts on the actuator 40, the reaction force F1 in the X2 direction also acts on the housing portion 10 that supports the actuator 40. The disk pad 21 is attracted to the X1 side surface of the disk rotor R by the reaction force F1, so that the disk rotor R is sandwiched between the disk pad 20 and the disk pad 21, and the disk rotor R and each of the disk pads 20, 21 Braking force is generated in the disk rotor R.

  Further, when the housing part 10 receives the reaction force F1 as described above, the housing part 10 is distorted. Therefore, a force (shaded arrow) based on this distortion is applied to the spherical body 70 (on the pressing force detector S1). (See FIG. 3). Based on the detection value detected by the pressing force detector S1 at this time, the pressing force F1 when the disk pad 20 presses the disk rotor R can be detected. That is, when the distortion of the housing portion 10 due to the reaction force F1 is large and the pressing force input to the pressing force detector S1 is large, it can be determined that the disc pad 20 is pressing the disc rotor R with a large pressing force. Further, when the distortion of the housing portion 10 is small and the pressing force input to the pressing force detector S1 is small, it can be determined that the disc pad 20 is pressing the disc rotor R with a small pressing force.

  Further, in the mounting structure of this embodiment, the pressing force detector S1 can be provided at a position away from the disk pads 20 and 21 so as to be covered with the housing portion 10, so that the disk pads 20 and 21 and the disk at the time of braking can be provided. The influence of frictional heat and vibration with the rotor R can be reduced, noise due to the heat and vibration can be reduced, and the accuracy during detection can be increased.

  FIG. 5 is a cross-sectional view showing a modification of the mounting structure of the pressing force detector of the present embodiment. A braking device 1 </ b> A shown in FIG. 5 is obtained by providing a pressing force detector S <b> 1 at another position of the housing portion 10 in the braking device 1 described above. Since the other configuration is the same as that of the braking device 1 described above, the description thereof is omitted. As described above, when the pressing force detector S1 is arranged at a position further away from the disk pads 20 and 21, the housing by the reaction force F1 (see FIG. 4) in a state where the influence of frictional heat and vibration is further reduced. By detecting the distortion of the portion 10 by the pressing force detector S1, it becomes possible to detect the pressing force when the disk pad 20 presses the disk rotor R.

  The present invention is not limited to the mounting structure in the braking devices 1 and 1A as long as the position can receive a reaction force when the disk rotor R is pressed. For example, the pressing force detector S <b> 1 may be provided at a position where the reaction force from the rotating member 42 of the actuator 40 is directly received, or may be provided at the boundary between the case 12 and the case 13 of the main body 11.

  In the braking device 1 described above, the motor M is used as the power of the actuator 40. However, the present invention is not limited to this, and hydraulic pressure or air pressure may be used. The configuration of the actuator 40 is not limited to the present embodiment, and the rotating member 42 may be fixed to the housing portion 10 so that the power of the motor M is directly transmitted to the advancing / retreating member 43 side. .

  Further, the present invention is not limited to the braking devices 1 and 1A, and can be widely applied to various pressing mechanisms that press the pressed member with the pressing member.

It is sectional drawing which shows the attachment structure of the pressing force detector of this embodiment. It is sectional drawing which shows the internal structure of a pressing force detector. It is sectional drawing which shows the example of mounting to the housing part of a pressing force detector. It is an effect | action figure in the attachment structure of the pressing force detector of this embodiment. It is sectional drawing which shows the modification of the attachment structure of the pressing force detector of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1A Braking device 10 Housing part 11 Main body part 13a Storage recessed part 15 Claw part 20, 21 Disc pad (pressing member)
40 Actuator 41 Piston 42 Rotating member 43 Advance / Retreat member 44 Ball 60 Base 70 Spherical body 80 Cover 90 Strain detecting element BK1 Bracket R Disk rotor (member to be pressed)
S1 Pressure detector

Claims (1)

A pressing force detector mounting structure in a braking device that generates a braking force on the disk rotor by sandwiching the disk rotor between a pair of disk pads,
A piston that presses one of the disk pads;
An actuator for moving the piston in an axial direction;
A bottomed cylindrical main body that supports one of the disk pads and the piston movably through the actuator, and an L-shaped claw section that is fixed to the main body and supports the other disk pad. a housing portion having a comprises,
In the main body of the housing part , a storage recess to which only the pressing force detector is fixed is formed, and the pressing force detector is arranged to be in contact with the storage recess so as to be covered by the main body ,
The pressing force detector indirectly detects a reaction force acting on the housing part by a pressing force of the disk pad against the disk rotor by the piston by a force based on distortion of the housing part. Mounting structure of the pressing force detector.

Images