JP2018141729A - Tread force detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tread force detection device capable of improving detection accuracy for tread force with a simple structure.SOLUTION: A tread force detection device includes: a shaft member 3 configured to rotatably support a brake operation member 7; a support member 2 configured to support portions on both sides of the brake operation member 7 in the shaft member 3, and transmit tread force to a master cylinder 61 side; and a tread force detector 4 configured to detect tread force transmitted to the master cylinder 61 side through the shaft member 3 and the support member 2. The tread force detector 4 includes strain detection units 411-414 provided in the shaft member 3 and configured to detect strain of the shaft member 3, and a calculation unit 42 configured to calculate tread force on the basis of the detection results of the strain detection units 411-414.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a pedaling force detection device that detects a pedaling force applied to a brake operation member.

  The pedaling force detection device is a device that is mounted on a vehicle and detects a pedaling force (load) applied by a driver to a brake pedal. For example, in Japanese Patent Application Laid-Open No. 2008-146629, a brake pedal, a clevis fixed to an end of an operating rod, a connecting shaft that connects the brake pedal and the clevis, and a connecting shaft and the brake pedal are arranged. There is described a pedal operation amount detection device including a bush and a detector for detecting a load disposed on an outer peripheral surface of the bush.

JP 2008-146629 A

  However, in the above detection device, a specially shaped bush must be inserted between the connecting shaft and the brake pedal, and there is room for improvement in terms of simplification of the configuration. Further improvement of pedaling force detection accuracy is another problem.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a pedaling force detection device capable of improving the pedaling force detection accuracy with a simple configuration.

  The pedaling force detection device of the present invention is a pedaling force detection device that is disposed between a brake operation member and a master cylinder, and is applied to a pedaling force transmission mechanism that transmits a pedaling force on the brake operation member to the master cylinder side. A shaft member that rotatably supports the brake operation member; a support member that supports portions of the shaft member on both sides of the brake operation member; and that transmits the pedal force to the master cylinder side; the shaft member; A pedaling force detector that detects the pedaling force transmitted to the master cylinder side via a support member, and the pedaling force detector is disposed on the shaft member and detects a strain of the shaft member; A calculation unit that calculates the pedal effort based on a detection result of the strain detection unit.

  According to the present invention, since the strain detecting unit is arranged on the shaft member to directly detect the strain of the shaft member, the shaft member itself functions as a strain generating body, and a member such as a special bush is unnecessary. Become. That is, the pedaling force detection device has a simple configuration. The detection target of the strain detection unit is a shaft member that directly receives the pedaling force of the brake operation member and transmits it to the master cylinder side together with the support member. For this reason, it becomes possible to directly detect the distortion caused by the pedaling force, suppress the occurrence of disturbance due to the intervention of other members, and improve the detection accuracy of the pedaling force.

It is a block diagram which shows the pedal effort detection apparatus of 1st embodiment. It is the II-II sectional view taken on the line of FIG. It is a block diagram which shows the clevis pin and strain gauge of 1st embodiment. It is explanatory drawing which shows the clevis pin and strain gauge of 1st embodiment. It is a block diagram which shows the pedal effort detection apparatus of 2nd embodiment. It is a block diagram which shows the pedal effort detection apparatus of 2nd embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings. Each figure used for explanation is a conceptual diagram, and the shape of each part may not necessarily be exact.

  The pedaling force detection device 1 of the first embodiment is a device that is disposed between the brake pedal 7 and the master cylinder 61 and is applied to the pedaling force transmission mechanism Z that transmits the pedaling force on the brake pedal 7 to the master cylinder 61 side. As shown in FIGS. 1 and 2, the pedaling force detection device 1 includes a clevis (corresponding to “support member”) 2, a clevis pin (corresponding to “shaft member”) 3, and a pedaling force detector 4. ing. The clevis 2 is a substantially U-shaped metal member connected to the input rod 5. The clevis 2 is fixed by being screwed to the proximal end portion of the input rod 5. The distal end portion of the input rod 5 is connected to a hydraulic pressure generating unit 6 including a master cylinder 61 and a booster 62. Hereinafter, in the description, the direction from the proximal end portion to the distal end portion of the input rod 5 (the direction in which the pedal force is applied from the brake pedal 7 to the clevis pin 3) is defined as the front, and the opposite direction is defined as the rear. As the input rod 5 advances, a master piston (not shown) in the master cylinder 61 advances.

  The clevis 2 includes bifurcated portions 21 and 22 arranged to face each other. The clevis pin 3 is inserted into the through hole 2a provided in the bifurcated portions 21 and 22. As described above, the clevis 2 is a member that supports portions of the clevis pin 3 on both sides of the brake pedal 7 and transmits the pedaling force to the master cylinder 61 side. The clevis pin 3 is a shaft-like metal member (columnar member), and connects the clevis 2 and the brake pedal 7 so as to be rotatable. That is, the clevis pin 3 is a member that rotatably supports the brake pedal 7. The clevis pin 3 penetrates the brake pedal 7, and the portions on both sides of the brake pedal 7 in the axial direction of the clevis pin 3 are supported by the bifurcated portions 21 and 22 of the clevis 2. That is, an intermediate portion of the brake pedal 7 is disposed between the bifurcated portions 21 and 22 of the clevis 2, and the clevis pin 3 penetrates the brake pedal 7 and the bifurcated portions 21 and 22 so as to pivotally connect the two. ing. The clevis pin 3 is positioned (fixed) with respect to the clevis 2. As described above, the clevis pin 3 is a member that rotatably connects the clevis 2 and the brake pedal 7, and both ends in the axial direction are supported by the clevis 2.

  The brake pedal 7 is a brake operation member configured such that an upper end portion thereof is rotatably supported by a mounting portion 71 on the vehicle body side by a support shaft 72 and a pedal member 73 is attached to a lower end portion. When the driver depresses the brake pedal 7, the brake pedal 7 (main body part) rotates via the support shaft 72, and the pedaling force and the operation amount are input (transmitted) to the input rod 5 via the clevis pin 3 and the clevis 2. Is done. Thereby, the input rod 5 moves to one side (front) in the axial direction, and the hydraulic pressure generating unit 6 is operated.

  The pedaling force detector 4 is a device that detects the pedaling force applied to the brake pedal 7 that is input to the input rod 5 via the clevis pin 3 and the clevis 2. Specifically, the pedaling force detector 4 includes a plurality of strain gauges (corresponding to “strain detectors”) 411, 412, 413, and 414, and a calculator 42. The strain gauges 411 to 414 are sensors that measure the strain of the measurement object. The strain gauges 411 to 414 are electric resistance sensors that are arranged (for example, bonded) to the measurement object and change in resistance value according to the expansion and contraction of the measurement object. The strain gauges 411 to 414 are arranged on the outer peripheral surface of the clevis pin 3. That is, in this embodiment, the clevis pin 3 itself is a measurement object of the strain gauges 411 to 414 and is a strain generating body. In the present embodiment, four strain gauges 411 to 414 are arranged on the clevis pin 3.

  As shown in FIGS. 2 and 3, the strain gauges 411 and 412 are arranged at a front portion of the outer peripheral surface of the clevis pin 3. The strain gauges 413 and 414 are arranged in a rear portion of the outer peripheral surface of the clevis pin 3 so as to face the strain gauges 411 and 412 (opposite via the clevis pin 3). Further, the strain gauges 411 and 413 are arranged at a portion on one side in the axial direction that does not overlap the brake pedal 7 in the axial direction of the clevis pin 3. The strain gauges 412 and 414 are disposed in a portion on the other side in the axial direction that does not overlap the brake pedal 7 in the axial direction of the clevis pin 3. That is, the strain gauges 411 to 414 are disposed between the clevis 2 (contact portion between the clevis 2 and the clevis pin 3) and the brake pedal 7 in the axial direction of the clevis pin 3. As described above, the strain gauges 411 to 414 are arranged at the portions on both sides of the brake pedal 7 in the axial direction of the clevis pin 3.

  The calculation unit 42 is a calculation device, and is connected to the strain gauges 411 to 414 via a signal line (wiring) 43. The calculating part 42 of this embodiment is implement | achieved by brake ECU9 (electronic control unit). That is, the brake ECU 9 includes the calculation unit 42 as a function. The computing unit 42 computes the pedaling force applied to the driver's brake pedal 7 based on the detection results of the strain gauges 411 to 414. The calculation unit 42 calculates the strain amount of the clevis pin 3 based on the one-side expansion / contraction data detected by the pair of strain gauges 411 and 413 and the other-side expansion / contraction data detected by the pair of strain gauges 412 and 414. Then, the calculation result is converted into a pedal effort.

  As shown in FIG. 4, when the brake pedal 7 is depressed, the central portion of the clevis pin 3 is bent and deformed so as to protrude forward, the front portion of the clevis pin 3 extends, and the rear portion shrinks. The strain gauges 411 to 414 detect the strain of the clevis pin 3, and the detection result is transmitted to the calculation unit 42. The calculation unit 42 calculates the strain amount of the clevis pin 3 based on the received detection result, and converts the strain amount into a pedaling force.

  According to the first embodiment, the clevis pin 3 also functions as a strain generating body, and the strain gauges 411 to 414 directly detect the strain amount of the clevis pin 3. Since the clevis pin 3 directly receives the pedaling force applied to the brake pedal 7, the strain amount of the clevis pin 3 is a value (a value having a high correlation) directly related to the magnitude of the pedaling force applied to the brake pedal 7. That is, by detecting the strain amount of the clevis pin 3 with high accuracy, the pedal effort can be detected with high accuracy. By using the clevis pin 3 that receives the pedaling force and transmits it to the clevis 2 as a strain detection target, it is possible to improve the pedaling force detection accuracy. Moreover, according to this structure, members, such as a special-shaped bush, are unnecessary, and it can be set as a simple structure. Further, with a simple configuration, it is possible to suppress disturbance due to other members such as a bush from affecting the detection result, and to improve the pedaling force detection accuracy. According to the present embodiment, processing of the brake pedal 7 and the like is not necessary, and can be easily applied to an existing vehicle braking device.

  Moreover, since the strain gauges 411-414 are arrange | positioned in the position which does not overlap with the brake pedal 7, it is hard to receive the interference of the brake pedal 7, and the disturbance in a detection is suppressed. In addition, since the strain gauges 411 to 414 are arranged at positions that are not the apex portion of the clevis pin 3 curve (that is, positions that are not the central portion of the clevis pin 3 in the axial direction), the clevis pin 3 curve (extension) is more reliably detected. can do. As described above, the strain gauges 411 and 412 have the clevis pins 3 between the “one of the parts on both sides of the brake pedal 7 on which the clevis pin 3 is supported” and the “brake pedal 7”, and the “clevis pin 3 supports. It is preferable that the brake pedal 7 is disposed at least at one side between the other side of the brake pedal 7 and the “brake pedal 7”.

<Second embodiment>
The pedal force detection device 1A of the second embodiment is different from the first embodiment in the configuration of the clevis pin and the pedal force detector. Therefore, a different part is demonstrated. In the description of the second embodiment, the description of the first embodiment and the drawings can be referred to as appropriate.

  As shown in FIG. 5, the clevis pin 30 of the second embodiment is formed in a cylindrical shape. That is, the clevis pin 30 has an arrangement chamber 30a that communicates with the outside. In other words, the clevis pin 3 has a through hole (30a) penetrating in the axial direction.

  The pedaling force detector 4A of the second embodiment includes an optical fiber (corresponding to a “strain detector”) 41A and a calculator 42. The optical fiber 41 </ b> A is arranged in the arrangement chamber 30 a along the central axis of the clevis pin 3. That is, the optical fiber 41A is arranged in the arrangement chamber 30a so as to extend in the axial direction of the clevis pin 3. The optical fiber 41A is an optical fiber in which one end and the other end are connected to the calculation unit 42 (brake ECU 9), and a part between the one end and the other end is arranged in the arrangement chamber 30a. That is, a part of the optical fiber 41A is disposed inside the clevis pin 30 as a strain detection unit. The optical fiber 41 </ b> A also serves as a signal line connected to the calculation unit 42. In FIG. 5, a part of the optical fiber 41A is represented by a dotted line for the sake of expression.

  A minute clearance is formed between the inner peripheral surface of the clevis pin 30 and the optical fiber 41A. That is, the arrangement chamber 30a is formed in a size corresponding to the thickness of the optical fiber 41A so that the optical fiber 41A deforms following the deformation of the clevis pin 3. For example, based on the response time (reflection time) of the signal passing through the optical fiber 41A, the calculation unit 42 calculates the strain amount of the clevis pin 3 (the bending amount of the optical fiber 41A) and converts the strain amount into a pedaling force.

  Also with this configuration, the optical fiber 41A is deformed in accordance with the deformation of the clevis pin 30 that receives the pedaling force, and the response time of the signal changes due to the deformation of the optical fiber 41A, and the pedaling force can be calculated based on the amount of change. . According to the second embodiment, as with the first embodiment, the optical fiber 41A directly detects the deformation of the clevis pin 3, so that the treading force detection accuracy can be improved. Further, in terms of processing, it is sufficient to provide the arrangement chamber 30a (here, a through hole) in the clevis pin 30, and the manufacturing is simple and simple. In the second embodiment, as in the first embodiment, it is not necessary to add a special bush, and the factor of disturbance is reduced.

  Further, since the means for detecting strain (here, the optical fiber 41A) is arranged in the arrangement chamber 30a inside the clevis pin 3, the strain detecting means may interfere (contact etc.) with other members. It is suppressed. Thereby, disturbance can be further suppressed and pedaling force detection accuracy can be improved.

<Third embodiment>
The pedal effort detector 1B of the third embodiment is different from the second embodiment in the configuration of the pedal effort detector. Therefore, a different part is demonstrated. In the description of the third embodiment, the descriptions and drawings of the first and second embodiments can be referred to as appropriate.

  The pedaling force detector 4B of the third embodiment includes a plurality of strain gauges 411 to 414 and a calculation unit 42. The configurations of the strain gauges 411 to 414 and the calculation unit 42 excluding the arrangement position are the same as those in the first embodiment. The strain gauges 411 to 414 of the third embodiment are arranged in the arrangement chamber 30a. The strain gauges 411 to 414 are arranged between the brake pedal 7 and the clevis 2 in the axial direction of the clevis pin 3 in the arrangement chamber 30a. The strain gauges 411 to 414 are disposed on the both sides of the brake pedal 7 in the axial direction of the clevis pin 3.

  Specifically, the strain gauge 411 is arranged on the inner peripheral surface of the clevis pin 3 that defines the front side of the arrangement chamber 30a on one axial side of the clevis pin 3. The strain gauge 412 is arranged on the inner peripheral surface of the clevis pin 3 that defines the front side of the arrangement chamber 30 a on the other axial side of the clevis pin 3. The strain gauge 413 is arranged on the inner peripheral surface of the clevis pin 3 that defines the rear side of the arrangement chamber 30a so as to face the strain gauge 411 on one side of the clevis pin 3 in the axial direction. The strain gauge 414 is disposed on the inner peripheral surface of the clevis pin 3 that defines the rear side of the placement chamber 30a so as to face the strain gauge 412 on the other axial side of the clevis pin 3.

  A part of the plurality of signal lines 43 is arranged in the arrangement chamber 30a, and connects the strain gauges 411 to 414 and the calculation unit 42 (brake ECU 9). Similar to the first embodiment, the computing unit 42 computes the amount of strain of the clevis pin 30 based on the detection results of the strain gauges 411 to 414 to calculate the pedal effort.

  Also in the third embodiment, as in the second embodiment, the above-described configuration can be realized by processing the clevis pin 30 that is relatively easy to process. Therefore, the configuration can be simplified, and the strain amount of the clevis pin 30 can be directly set. Thus, the treading force detection accuracy can be improved. Moreover, since the strain detection means (here, the strain gauges 411 to 414) are arranged in the arrangement chamber 30a inside the clevis pin 30 as in the second embodiment, disturbance in detection is suppressed. Furthermore, in 3rd embodiment, since the whole strain gauges 411-414 which are a detection means are arrange | positioned in the clevis pin 3 (arrangement chamber 30a), it becomes a structure which is hard to receive a disturbance more. Further, since the strain gauges 411 to 414 are arranged between the brake pedal 7 and the axial end of the clevis pin 3 in the axial direction of the clevis pin 3, as in the first embodiment, the strain of the clevis pin 3 is more reliably ensured. Can be detected.

(Other)
The present invention is not limited to the above embodiment. For example, the number of strain gauges may be one or plural, and the arrangement position with respect to the clevis pin 3 may be other than the above. However, it is preferable that a plurality of strain gauges are arranged with respect to the clevis pins 3 and 30, and it is preferable that two strain gauges are arranged so as to face each other in the front-rear direction. In addition, the shape of the clevis pins 3 and 30 may be a bottomed cylindrical shape having a bottom surface at one end in the axial direction. In this case, one end of the optical fiber 41A may be fixed to the bottom surface. Further, the clevis pin 30 may include a wall portion that divides the arrangement chamber 30a into two. However, as in the second and third embodiments, the arrangement chamber 30a is preferably formed by a through hole from the viewpoint of processability and sensor arrangement. Further, the clevis pin 3 may be positioned (fixed) with respect to the brake pedal 7 instead of the clevis 2. Moreover, the calculating part 42 may calculate a pedal effort directly based on the detection result (information regarding distortion) transmitted from the strain gauges 411-414 or the optical fiber 41A. The strain detector may be any sensor that can detect the strain of the clevis pins 3 and 30. Further, the brake pedal 7 is not limited to the central portion of the clevis pins 3 and 30 and may be supported by a portion other than the central portion. Further, the booster 62 may not be provided.

DESCRIPTION OF SYMBOLS 1, 1A, 1B ... Treading force detection apparatus, 2 ... Clevis (support member) 3, 30 ... Clevis pin (shaft member), 30a ... Arrangement chamber 4, 4A, 4B ... Treading force detector, 411-414 ... Strain gauge ( Strain detector), 41A ... optical fiber (strain detector), 42 ... calculator, 43 ... signal line, 5 ... input rod, 6 ... hydraulic pressure generator, 7 ... brake pedal (brake operating member), 9 ... brake ECU.

Claims (4)

A pedaling force detection device that is disposed between a brake operation member and a master cylinder and that is applied to a pedaling force transmission mechanism that transmits a pedaling force on the brake operation member to the master cylinder side,
A shaft member that rotatably supports the brake operation member; a support member that supports portions of the shaft member on both sides of the brake operation member; and that transmits the pedaling force to the master cylinder side; and the shaft member; A pedaling force detector for detecting the pedaling force transmitted to the master cylinder side via the support member,
The pedaling force detector includes a strain detector that is disposed on the shaft member and detects strain of the shaft member, and a computing unit that calculates the pedaling force based on a detection result of the strain detector. The shaft member has a disposition chamber communicating with the outside inside,
The pedaling force detection device according to claim 1, wherein the strain detection unit is arranged in the arrangement chamber.   The pedaling force detection device according to claim 2, wherein the strain detection unit is an optical fiber arranged in the arrangement chamber along a central axis of the shaft member.   The strain detector is provided between at least one of the parts on both sides of the brake operation member and the brake operation member, and at least one between the other of the parts on both sides of the brake operation member and the brake operation member. The pedal effort detection device according to claim 2 arranged.

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