JP2001334919A - Detector for leg-power of brake pedal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the detection precision of leg-power in the ordinary area of a brake pedal. SOLUTION: This detector comprises an elastically deformable pivotal member 22 supported on a pedal arm 10 by a pivotal shaft 20 substantially parallel to the support shaft 16 of the pedal arm 10, a connecting pin 24 for connecting the pivotal member to one end of a push rod 30, a compression coil spring 32 for energizing the pivotal member around the pivotal shaft relatively to the pedal arm in the direction of pressing the push rod toward a brake device, a relative position setting device 38 for setting the relative position of the pivotal member around the pivotal shaft to the pedal arm so that the connecting pin is separated from the pedal arm, and a distortion sensor 56 for detecting the elastic deformation of the pivotal member. When the leg-power of a driver is a prescribed value or more, the pivotal member is relatively pivotally moved to the pedal arm against the energizing force of the energizing means, so that the connecting pin abuts on the pedal arm to directly receive a force from the pedal arm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake pedal for a vehicle such as an automobile, and more particularly to a brake pedal depression force detecting device.

[0002]

2. Description of the Related Art A brake pedal incorporated in a vehicle such as an automobile generally has a pedal arm which is pivotally supported at one end by a support shaft and receives a driver's treading force at the other end, and corresponds to the treading force of the driver. The force is transmitted to a braking device such as a master cylinder or a booster via a push rod. As a device for detecting the depression force of a brake pedal, for example, Japanese Patent Application Laid-Open Nos. As described in Japanese Patent Application Laid-Open No. 11-255084, a strain detection type tread force detecting device in which a strain sensor is provided on a pedal arm or a connecting member called a clevis for connecting the pedal arm and the push rod is conventionally known. .

In general, when a driver depresses a brake pedal, a pedal arm or a clevis is elastically deformed as a strain generating member due to a depressing force and a reaction force from a push rod. Since it is proportional, according to the pedal force detection device as described above,
The depression force on the brake pedal is detected by detecting the amount of elastic deformation of the distortion generating member by the distortion sensor.

[0004]

However, in the above-described conventional strain detection type tread force detecting device, there is a trade-off between the breaking limit of the strain generating member and the dynamic range of the tread force detecting device. It is difficult to sufficiently improve the detection accuracy of the detection device. That is, in order to improve the detection accuracy of the pedaling force detection device, the ratio of the amount of elastic deformation of the strain generating member to the pedaling force may be increased. In this case, when a strong pedaling force is applied to the brake pedal, the distortion generating member Since the elastic deformation amount of the elastic member becomes very large and approaches the breaking limit, there is a limit in increasing the ratio of the elastic deformation amount of the strain generating member to the pedal force, and therefore, the detection accuracy of the pedal force detecting device is sufficiently improved. Can not do.

In vehicle control such as braking force control performed based on the treading force detected by a treading force detecting device, the treading force of the brake pedal in the normal range generally needs to be detected with high accuracy. On the other hand, since the control amount such as the braking force control in the region where the pedaling force is very high is set to be saturated, it is unnecessary to detect the pedaling force in the region where the pedaling force is very high.

The present invention has been made in view of the above-described problems in a conventional pedaling force detecting device configured to detect the pedaling force of a brake pedal by detecting the amount of elastic deformation of a strain generating member such as a pedal arm. The main problem of the present invention is that the pedaling force in the normal range of the brake pedal needs to be detected with high accuracy, whereas the detection of the pedaling force in a very high region is unnecessary. It is another object of the present invention to improve the accuracy of detecting the pedaling force in the normal region of the brake pedal by limiting the stress applied to the strain generating member in a region where the pedaling force on the brake pedal is extremely high.

[0007]

SUMMARY OF THE INVENTION According to the present invention, there is provided, in accordance with the present invention, a structure as claimed in claim 1, i.e. the driver's treading force at a position pivotally supported by a support shaft and spaced from the support shaft. A pedal arm for receiving a driver's depressing force, and transmitting a force corresponding to a driver's depressing force to a braking device via a push rod, wherein the pedal arm has a pivot substantially parallel to the support shaft. An elastically deformable pivot member pivotally supported by a connecting pin connecting the pivot member to one end of the push rod at a position separated from the pivot, and directing the push rod toward the braking device. Biasing means for biasing the pivoting member relative to the pedal arm about the pivot axis in a pressing direction; and a front with respect to the pedal arm such that the connecting pin is spaced from the pedal arm. It has relative position setting means for setting a relative position of the pivot member around a pivot, and detection means for detecting the amount of elastic deformation of the pivot member, and the pedaling force of the driver is determined by the urging force of the urging means. When the value is equal to or more than the predetermined value, the pivoting member pivots relatively to the pedal arm against the urging force of the urging means, and the connecting pin comes into contact with the pedal arm and moves from the pedal arm. This is achieved by a brake pedal depression force detection device characterized in that it is configured to receive a direct force.

According to the first aspect of the present invention, the relative position of the pivot member about the pivot axis with respect to the pedal arm is set by the relative position setting means so that the connecting pin is separated from the pedal arm. When the pedal arm is depressed by the driver when the driver's treading force is less than a predetermined value determined by the urging force of the urging means, a force corresponding to the treading force is applied from the pedal arm to the pivot, the pivoting member, and the connecting pin. The pivoting member is elastically deformed as a strain generating member due to the force received from the pedal arm and the reaction force from the push rod, and the amount of elastic deformation is proportional to the pedaling force on the pedal arm and detected by the detecting means. The pedaling force on the pedal arm is detected indirectly.

Further, when the pedal arm is depressed by the driver with the driver's depressing force being a predetermined value or more determined by the urging force of the urging means, the pivoting member moves against the pedal arm against the urging force of the urging means. Pivot relatively, the connecting pin comes into contact with the pedal arm and receives a direct force from the pedal arm, and a part of the force corresponding to the pedaling force is transmitted from the pedal arm to the push rod via the connecting pin. Therefore, even if the pedal arm is depressed by the driver with a pedaling force higher than a predetermined value, the force applied to the pivoting member by the pedal arm does not increase. Therefore, it is possible to increase the ratio of the amount of elastic deformation of the pivoting member to the pedaling force and to improve the detection accuracy of the pedaling force detection device, while avoiding the pivoting member from receiving excessive stress.

According to the present invention, in order to effectively achieve the above-mentioned main object, in the configuration of the first aspect, the pedal arm has a hole for receiving the connecting pin in a loosely fitted state. When the driver's treading force is less than the predetermined value, the connection pin is separated from the wall surface of the hole, and when the driver's treading force is equal to or more than the predetermined value, the connection pin contacts the wall surface of the hole. Thereby, it is configured to receive a direct force from the pedal arm (the configuration of claim 2).

According to the second aspect of the present invention, the connecting pin is inserted into the hole provided in the pedal arm, and when the driver's treading force is equal to or more than a predetermined value, the connecting pin comes into contact with the wall surface of the hole to thereby provide the pedal arm. Since the force is received more directly, the force is reliably transmitted from the pedal arm to the push rod via the connecting pin when the driver's pedaling force is equal to or greater than the predetermined value.

[0012]

According to a preferred aspect of the present invention, in the configuration of the first aspect, the biasing means is configured to include a means for adjusting the biasing force (preferred aspect 1). .

According to another preferred aspect of the present invention, in the configuration of the first aspect, the relative position setting means is configured to be capable of adjusting a distance between the connecting pin and the pedal arm ( Preferred embodiment 2).

According to another preferred embodiment of the present invention, in the structure of the first aspect, the connecting pin is located between the support shaft and the pivot, and the biasing force is opposite to the pivot with respect to the connecting pin. (Preferred embodiment 3).

According to another preferred embodiment of the present invention, in the configuration of the first aspect, the distance between the axis of the pivot and the axis of the connecting pin is determined by the position of the axis of the pivot and the position receiving the biasing force. (Preferred mode 4).

According to another preferred embodiment of the present invention, in the structure of the first aspect, the pivot member has a flat plate portion extending substantially perpendicular to the axis of the push rod. The detecting means is configured to detect an elastic deformation amount of the flat plate portion at least between the pivot and the connecting pin (preferred mode 5).

According to another preferred embodiment of the present invention, in the configuration of the aforementioned preferred embodiment 5, the detecting means is configured to detect an amount of strain on a surface of the flat plate portion opposite to the push rod. (Preferred embodiment 6).

According to another preferred embodiment of the present invention, in the configuration of the above-mentioned preferred embodiment 5, the pivoting member is formed integrally with the flat plate portion and extends parallel to each other on both sides of the pedal arm. And a pair of first brackets configured to support both ends of the pivot (preferred embodiment 7).

According to another preferred embodiment of the present invention, in the configuration of the aforementioned preferred embodiment 7, the pivoting member is formed integrally with the flat plate portion at a position separated from the pair of first brackets. And a pair of second brackets extending parallel to each other on both sides of the pedal arm, and the pair of second brackets are configured to support both ends of the connection pin so as to be relatively rotatable (a preferred embodiment). 8).

According to another preferred embodiment of the present invention, in the configuration of the preferred embodiment 8, the distal ends of the pair of second brackets are curved in a direction approaching the pivot, and the connecting pins are provided at the distal ends. Are supported so that they can rotate relative to each other,
The detecting means is configured to detect the amount of elastic deformation of the pivoting member on both sides in the extending direction of the flat plate portion with respect to the intersection between the axis of the push rod and the flat plate portion (preferred embodiment 9).

According to another preferred embodiment of the present invention, in the configuration of the above-described preferred embodiment 9, the detecting means is provided on a surface of the plate portion opposite to the push rod on the pivot side with respect to the intersection. A first detection unit that detects the amount of distortion, and a second detection unit that detects the amount of distortion on the surface opposite to the push rod of the flat plate portion on the side opposite to the pivot with respect to the intersection. (Preferred embodiment 10).

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a side view showing one embodiment of a brake pedal depression force detecting device according to the present invention in a standard state where no depression force is applied. FIGS. 2 and 3 respectively show a case where the depression force of the brake pedal is less than a predetermined value. FIG. 2 is an enlarged partial side view partially showing a main part of the embodiment with a part omitted, and an exploded plan sectional view showing the operation of the embodiment.

In these figures, reference numeral 10 denotes a pedal arm of the brake pedal 12, and the pedal arm 10
A boss 12A is provided at one end (upper end), and a pedal member 14 is provided at the other end (lower end). The pedal arm 10 is pivotally supported on a vehicle body (not shown in FIG. 1) by a support shaft 16 inserted into the boss portion 12A via a bush 16A, and a pedal member as shown by an arrow Fd in FIG. At 14, the driver's pedaling force is applied to the support shaft 16 against the spring force of a return spring (not shown).
Around it in a counterclockwise direction as seen in FIG. In FIG. 1, reference numeral 12B denotes a bracket which is connected to the vehicle body at one end and to which the other end of a return spring for urging the pedal arm 10 clockwise around the support shaft 16 is connected.

The pedal arm 10 is provided with a hole 18 at a position between the support shaft 16 and the pedal member 14.
A pivot 20 extending substantially parallel to the support shaft 16 is rotatably inserted through 8. A pivoting member 22 made of an elastically deformable material is disposed at a position close to the pivot 20, and the pivoting member 22 substantially extends along the pedal arm 10 and is integrated with the flat portion 22A. And a pair of brackets 22B extending parallel to each other on both sides of the pedal arm 10. Bracket 22
B supports both ends of the pivot 20 so that the pivot member 22 can move the pedal arm 1 around the axis 20A of the pivot 20.
It is pivotally attached to the pedal arm so as to be rotatable relative to zero.

The pivot member 22 has a pair of brackets 22C formed integrally with the flat plate portion 22A at its upper end and extending parallel to each other on both sides of the pedal arm 10. A connection pin 24 extending substantially in parallel is rotatably inserted. Connecting pin 2
4 is loosely inserted into a pin receiving hole 26 provided on the pedal arm 10 and having a diameter D2 larger than the outer diameter D1 of the connecting pin 24, as described later in detail.

A clevis 28 as a connecting member is arranged at a position close to the connecting pin 24.
Has a pair of brackets 28A extending parallel to each other on both sides of the pedal arm 10 and the bracket 22C. The bracket 28A rotatably supports both ends of the connecting pin 24, so that the clevis 28 is connected to the connecting pin 2
4 pivotally attaches to the upper end of the pivot member 22. Although not shown in the drawing, a split pin is attached to the tip of the connecting pin 24 so as not to fall off.

As in the conventional case, one end of a push rod 30 is rigidly fixed to a portion 28B of the clevis 28 connecting the pair of brackets 28A by welding or the like.
The push rod 30 extends substantially in the longitudinal direction of the vehicle,
The other end is pivotally connected to a piston of a braking device such as a master cylinder or a brake booster not shown in FIG.

One end of a compression coil spring 32 is engaged with the lower end of the pivoting member 22 via a spring seat member 31, and the other end of the compression coil spring 32 is supported by an adjusting device 34 attached to the pedal arm 10. Thereby, the pivot member 22 is urged clockwise as viewed in FIG. 1 around the pivot 20 relative to the pedal arm 10 by the urging force (spring force) of the compression coil spring 32. As shown in FIG. 1, when viewed along the flat plate portion 22A of the pivot member 22, the pivot 2
Distance La between the axis 20A of 0 and the center of the connecting pin 24
Is set smaller than the distance Lb between the axis 20A of the pivot 20 and the center of the compression coil spring 32.

The adjusting device 34 includes an urging force adjusting device 36 for adjusting the urging force applied to the pivot member 22 by the compression coil spring 32, and a position adjusting device 38 for adjusting the relative position of the pivot member 22 to the pedal arm 10. And a casing 40 common to these adjustment devices.
The casing 40 has a substantially rectangular shape and is fixed to the side surface of the pedal arm 10 by screws 42.

The biasing force adjusting device 36 includes a nut 44 fixed to the casing 40 by welding or the like, and a bolt 46 is screwed to the nut 44. A spring seat member 4 for supporting the other end of the compression coil spring 32 is provided at the tip of the bolt 46.
8 by which the biasing force adjusting device 36 rotates the bolt 46 relative to the nut 44 to adjust the position of the spring seat member 48, whereby the pivoting member 22 is moved by the compression coil spring 32. Can be adjusted.

The position adjusting device 38 includes a nut 50 fixed to the casing 40 by welding or the like.
A bolt 52 is screwed into 0. The tip of the bolt 52 is engaged with a stopper 54 provided on the side of the tip of one bracket 22B, and a cutout hole 40A is provided in the bottom wall of the casing 40 so that the bolt 52 can be easily rotated. . Accordingly, the position adjuster 38 adjusts the relative rotational position of the pivot member 22 relative to the pedal arm 10 about the pivot 20 by rotating the bolt 52 relative to the nut 50 to adjust the position of the tip of the bolt 52. It is possible to do.

In this case, as shown in FIG. 2 and FIG. 3, the position adjusting device 38 controls the situation where the pedaling force is not applied to the brake pedal 12 and the situation where the pedaling force applied to the brake pedal 12 is less than a predetermined value described later. At this time, the connecting pin 24 is adjusted so as to be spaced from the wall on the left side in the view of the pin receiving hole 26, preferably substantially concentric with the pin receiving hole 26.

As understood from the above description, the compression coil spring 32 and the urging force adjusting device 36 cooperate with each other to move the pivot member 22 relative to the pedal arm 10 in the direction of pressing the push rod 30 toward the braking device. It constitutes a biasing means for biasing around the pivot 20. The position adjusting device 38 and the stopper 54 cooperate with each other to move the pivot member 22 about the pivot 20 with respect to the pedal arm 10 so that the connecting pin 24 is separated from the wall surface of the hole 26 that receives the connecting pin 24 in a loosely fitted state. It constitutes relative position setting means for setting the relative position.

As shown in FIGS. 1 and 6, the outer surface of the flat plate portion 22 A of the pivot member 22, that is, the surface on the side opposite to the pedal arm 10 side, is proportional to the depression force on the brake pedal 12. A distortion sensor 56 is provided as detection means for detecting the amount of elastic deformation of the flat plate portion 22A generated by the deformation.

In particular, in the illustrated embodiment, the pair of brackets 22C are spaced apart from the corresponding brackets 22B in the direction in which the flat plate portion 22A extends, and the tips of these brackets face the pivot 20. Plate 22A of the brackets 22B and 22C.
The connecting pin 24 is supported so as to be relatively rotatable at an intermediate position between the connecting portions. The distance between the axis of the connecting pin 24 and the outer surface of the flat plate portion 22A is set to be the same as the distance between the axis 20A of the pivot 20 and the outer surface of the flat plate portion 22A. May be different.

In the situation where the pedaling force is not applied to the brake pedal 12, the axis 5 of the push rod 30
Reference numeral 8 extends perpendicularly to the flat plate portion 22A, so that even if the pedal force is applied to the brake pedal 12 and the pedal arm 10 pivots around the support shaft 16, the axis 58 does not greatly incline with respect to the flat plate portion 22A. It is designed to maintain a vertical or nearly vertical state.

Therefore, as shown in FIG. 6, when the brake pedal 12 is depressed, the push rod 3
The force Fp applied to the connecting pin 24 from the zero through the clevis 28 acts along the axis 58, and the reaction force Fp ′ also acts along the axis 58. Assuming that a straight line passing through the axis 20A of the pivot 20 and being parallel to the axis 58 is 60, a compressive stress acts on the outer surface of the flat plate portion 22A in a region 62 between the axis 58 and the straight line 60. A tensile stress acts on the region 64 on the upper end (right end in FIG. 6).

The thickness and width of the flat plate portion 22A are T, respectively.
When the above-described two regions 62 and 64 are modeled as W, these regions can be considered as a pair of cantilever beams which are in contact with each other and face each other. In other words, the region 62 between the axis 58 and the straight line 60 has the position of the straight line 60 as a fixed end and the axis 58
Can be considered as a cantilever having a thickness T, a width W, and a length La at the tip where the load acts. Similarly, with respect to the region 64 on the upper end side with respect to the axis 58, the position opposite to the straight line 60 with respect to the axis 58 and the distance La from the axis 58 is a fixed end, and the position of the axis 58 is defined as the tip where the load acts. Can be considered as a cantilever having a thickness T, width W, and length La. Note that the solid line at the top of FIG. 6 shows an example of the stress in the cantilever model, and the broken line shows an example of the stress of the solid line.

The strain sensor 56 is provided at the position of the axis 58, and in the illustrated embodiment, is a strain gauge with a built-in four detection unit. Four detection units 56A to 5 of strain sensor 56
6D, the detection units 56A, 56B and 56C, 56D
Are located on both sides of the axis 58 at positions equidistant from the axis, and the detection units 56A, 56C and 56B, 56D are located on both sides of the center line 66 in the width direction of the flat plate section 22 at positions equidistant from the center line. Are located in

The four detectors 56A to 56D are provided with the strain sensors 5
6 is a resistor whose resistance value is increased by expansion of the outer surface of the flat plate portion 22A to which the plate 6 is attached, and which is reduced by contraction of the outer surface of the flat plate portion 22A to decrease the resistance value, as shown in FIG. Cooperate with each other to form a Wheatstone bridge circuit 68 as described above. In particular, the detection units 56A and 56C
Are connected in series with each other and are arranged in regions 62 and 64, respectively, and the detection units 56B and 56D are connected in series with each other and are arranged in regions 62 and 64, respectively.

A connecting section 70 between the detecting sections 56A and 56D
A and the voltage of the constant voltage DC power supply 72 is applied between the connection portion 70B between the detection portions 56C and 56B, and the detection portion 56A
70C and detecting units 56B and 56D between
The voltage Vin generated between the connection portion 70D and the connection portion 70D is input to the signal amplification processing circuit 74, and the signal of the voltage Vout amplified by the circuit is output as a signal indicating the pedaling force Fd.

Next, the operation of the embodiment configured as described above will be described in (1) when the pedaling force Fd is less than a predetermined value and (2).
A case where the pedaling force Fd is equal to or more than a predetermined value will be described.

(1) When the pedaling force Fd is less than a predetermined value Although not shown in the drawing, the distance between the axis of the support shaft 16 and the portion of the pedal member 14 that receives the pedaling force is represented by L1, and If the distance between the axis of the push rod 30 and the axis 58 of the push rod 30 is L2, the force Fp applied to the push rod 30 when the brake pedal 12 is depressed with the depression force Fd is expressed by the following equation (1). , A reaction force Fp 'of the same magnitude as that of the clevis 2
8 and a connecting pin 24 to the pivot member 22. Fp = Fd × (L1 / L2) (1)

Although not shown in the drawing, assuming that the spring force of the compression coil spring 32 is Fs, the rotational moment M1 about the pivot 20 applied to the pivot member 22 by the spring force Fs is Fs × Lb. And the rotational moment M2 around the pivot 20 due to the reaction force Fp 'from the push rod 30 =
As long as Fp '× La does not exceed the rotational moment M1, the compression coil spring 32 is not compressed, and the pivot member 22 does not pivot around the pivot 20 relative to the pedal arm 10.

Accordingly, if the pedaling force Fd when the two rotational moments M1 and M2 are equal to each other, that is, when Fs × Lb = Fp ′ × La holds, is a predetermined value Fdo, the predetermined value Fdo is given by the following equation (2). ), Is uniquely determined by the spring force Fs of the compression coil spring 32, and can be adjusted by the biasing force adjusting device 36. Fdo = Fs × (LbL2 / LaL1) (2)

When the pedaling force Fd applied to the brake pedal 12 by the driver is smaller than the predetermined value Fdo, the pedal arm 10 is moved in the state shown in FIG.
Pivots around the support shaft 18 and the connecting pin 24 maintains a state of being separated from the wall surface of the pin receiving hole 26 and does not receive a direct force from the pedal arm 10.
The force corresponding to d is transmitted from the pedal arm 10 to the pivot member 22 via the pivot 20, and further from the pivot member 22 to the push rod 30 via the connecting pin 24 and the clevis 28.
Is transmitted as the force represented by the above equation (1).

In such a situation, a reaction force Fp 'having the same magnitude as the force Fp but in the opposite direction is applied to the push rod 30.
The pivot member 2 via the clevis 28 and the connecting pin 24
2, a compressive stress and a tensile stress proportional to the treading force Fd act on the regions 62 and 64 on the outer surface of the plate portion 22A as described above, and a voltage signal Vout proportional to the magnitude of these stresses. Is output from the strain sensor 56, whereby the pedaling force Fd is detected.

(2) When the pedaling force Fd is equal to or greater than a predetermined value: The pedaling force Fd applied to the brake pedal 12 by the driver
Is greater than or equal to the predetermined value Fdo, the rotational moment M2 due to the reaction force Fp 'becomes larger than the rotational moment M1, so that the pivoting member 22 pedals around the pivot 20 against the spring force of the compression coil spring 32. As shown in FIG. 1, the connecting pin 24 is pivoted in a counterclockwise direction relative to the arm 10 so that the connecting pin 24 is inserted into the pin receiving hole 2 as shown in FIGS.
6, the force is transmitted and received between the connecting pin 24 and the pedal arm 10.

The spring force F of the compression coil spring 32 when the connecting pin 24 is in contact with the wall surface of the pin receiving hole 26
Although s 'is slightly higher than the spring force Fs, the difference between these spring forces is very small, so that Fs' can be approximately regarded as Fs, so that the force corresponding to a part Fd1 of the pedaling force Fd is The force Fp1 expressed by the following equation (3) corresponding to the equation (1)
Is transmitted to the push rod 30 in the same manner as when the pedal effort Fd is less than the predetermined value Fdo. Fp1 = Fd1 × (L1 / L2) (3)

The remaining force Fd2 of the pedaling force Fd (= Fd−Fd)
The force Fp2 (= Fp-Fp1) corresponding to 1) is applied to the pedal arm 1
0 to the connecting pin 24 and further to the clevis 28
Is transmitted to the push rod 30 via the clevis 28 and the connecting pin 24 from the push rod 30 so that the reaction force applied to the pivot member 22 from the push rod 30 is Fp1 'corresponding to Fp1.
And no excessive stress acts on the pivoting member 22.

Therefore, according to the illustrated embodiment, the above-mentioned predetermined value Fdo is set to the maximum value of the pedaling force of the brake pedal 12 in the normal range or a value slightly larger than the maximum value.
Even if a high pedaling force exceeding the normal range is applied to the brake pedal 12, excessive stress does not act on the pivoting member 22, so that the ratio of the amount of elastic deformation of the plate-like portion 22A of the pivoting member 22 to the pedaling force Fd is increased. Accordingly, the accuracy of detecting the treading force of the treading force detection device can be improved.

FIG. 8 shows the relationship between the pedaling force Fd applied to the brake pedal and the amount of elastic deformation of the strain generating member. In particular, the two-dot chain line shows the case of the conventional pedaling force detector, and the solid line shows the case of the illustrated embodiment. Is shown.

In a conventional pedaling force detecting device in which the strain generating member is a structural member such as a pedal arm or a clevis, the pedaling force F
Even when d is the maximum pedaling force Fdmax that can be applied to the brake pedal by the driver, the amount of elastic deformation of the strain generating member must be a value that has a margin with respect to its breaking limit. The ratio (the slope of the two-dot chain line graph) cannot be increased.

On the other hand, according to the illustrated embodiment, in the region where the pedaling force Fd is equal to or greater than the predetermined value Fdo, even if the pedaling force increases to the predetermined value or more, the strain generating member, that is, the plate of the pivoting member 22 is not affected. Since the elastic deformation amount of the plate-like portion 22A does not increase, it is sufficient that the elastic deformation amount when the pedaling force Fd is the predetermined value Fdo has a margin with respect to the breaking limit of the plate-like portion 22A, and therefore the pedaling force needs to be detected. The accuracy of the pedaling force detection can be improved by increasing the ratio of the amount of elastic deformation to the pedaling force Fd in the normal range (the slope of the solid line graph).

In particular, according to the illustrated embodiment, the pivot member 2
Since the connecting pin 24 for connecting the clevis 28 and the clevis 28 is loosely inserted into the pin receiving hole 26 provided in the pedal arm 10, the connecting pin 24 is, for example, on the right side of the pedal arm 10 in FIG. Compared to the case where
Clevis 2 from the pedal arm 10 via the connecting pin 24
8 and the push rod 30 can be reduced, and the height of the projection of the bracket 22C can be reduced, and the possibility of deterioration of the pedaling force detection accuracy due to the elastic deformation of the bracket 22C itself can be reduced. can do.

Further, according to the illustrated embodiment, the biasing force applied to the pivot member 22 by the compression coil spring 32 can be adjusted by the biasing force adjusting device 36, so that the pedal force detecting device according to the embodiment is applied. The predetermined value Fdo can be easily set according to the normal range of the depression force of the brake pedal in the vehicle.

Further, according to the illustrated embodiment, the distance between the connecting pin 24 and the wall surface of the pin receiving hole 26 can be adjusted by the position adjusting device 38, so that the vehicle to which the illustrated embodiment is applied can be adjusted. The distance can be freely set to an optimal value regardless of individual differences.

According to the illustrated embodiment, the pivot member 2
2A, the axis 20A of the pivot 20
Is the distance L between the axis 20A of the pivot 20 and the center of the compression coil spring 32.
b, the compression coil spring 32 causes the pivoting member 22 to move relative to the case where these distances are substantially the same or the case where the magnitude relationship of these distances is reversed. The spring force constantly applied to the pedaling force is reduced, thereby improving the durability of the pedaling force detection device.

According to the illustrated embodiment, the push rod 30 is viewed in the normal state of the brake pedal 12.
Of the pivot member 22 as a strain generating member
Since A and A have a vertical relationship, the plate-shaped portion 22A can be elastically deformed most efficiently by the reaction force Fp 'from the push rod 30, and this also increases the treading force detection accuracy of the treading force detecting device. Can be.

According to the illustrated embodiment, the brackets 22B and 22C are provided on both sides of the pedal arm 10 so as to extend in parallel with each other, and each of the two
0 and both ends of the connecting pin 24, the pivot 2
In order to transfer the force between these brackets, the pivot 20 and the connecting pin 24 better and more reliably than when the 0 or the connecting pin 24 is supported in a cantilever manner by a single bracket, for example. Can be.

According to the illustrated embodiment, the connecting pin 2
The bracket 22C supporting both ends of the fourth member 4 is substantially J-shaped, and a region 62 receiving a compressive stress and a region 64 receiving a tensile stress are formed on the outer surface of the plate-like portion 22A by the reaction force Fp 'from the push rod 30. Since the pair of detection units 56A and 56B and the detection units 56C and 56D of the four-detection-unit-incorporated strain sensor 56 are arranged in each area, the pair of detection units are distributed on the outer surface and the inner surface of the plate-shaped portion 22A, for example. The structure of the strain sensor can be simplified as compared with the case of disposing the sensors, and the manufacturing cost of the pedaling force detection device can be reduced.

Further, according to the illustrated embodiment, the pedal arm can be assembled to the vehicle in a state where the pivoting member 22 and the like constituting the pedaling force detection device are appropriately assembled in advance to the pedal arm 10. Compared to a case where the components of the pedaling force detection device are assembled to the pedal arm after the pedal arm 10 is assembled to the vehicle, the assembly of the pedaling force detection device can be easily performed, and the assembly is caused by an assembly error. Deterioration of the pedaling force detection accuracy can be reliably prevented.

Although the present invention has been described in detail with reference to specific embodiments, the present invention is not limited to the above-described embodiments, and various other embodiments may be included within the scope of the present invention. It will be clear to those skilled in the art that is possible.

For example, in the above-described embodiment, the bracket 22C is formed in a J-shape, and the plate-like portion 2 of the pivot member 22 is formed.
A region 62 receiving a compressive stress and a region 64 receiving a tensile stress are formed on the outer surface of the 2A, and a detecting unit of a strain gauge with a built-in 4 detecting unit is arranged in these regions. A portion above the pivot 20 of the member 22 may be configured to form a simple cantilever, and a strain gauge detection unit may be provided on the outer surface and the inner surface of the region of the cantilever.

In the above embodiment, the biasing means is the compression coil spring 32. However, the biasing means may be replaced by a tension spring located above the pivot 20, and the connecting pin 24 Is loosely inserted into a pin receiving hole 26 provided in the pedal arm 10,
The pedal arm 10 may be configured to be located on the right side of the pedal arm 10 in FIG.

In the above-described embodiment, the pivoting member 22 is provided on the side opposite to the push rod 30 with respect to the pedal arm 10, but may be provided on the same side as the push rod. In this case, the biasing means is preferably a tension spring that biases a portion of the pivot member 22 below the pivot 20 in a clockwise direction as viewed in FIG.

Furthermore, in the above-described embodiment, the signal of the voltage Vout of the signal amplification processing circuit 74 is output as a signal indicating the pedaling force Fd.
When the angle formed by the axis 58 of the push rod 30 with respect to the flat plate portion 22A of the pivoting member 22 changes relatively more than 90 ° by the depression of 2, the correction coefficient Ka is calculated according to, for example, the graph shown in FIG. And the strain sensor 56
May be corrected to KaVout, and this correction calculation may be performed in the signal amplification processing circuit 74, or in a control device such as a braking force control device performed using the pedal effort Fd. May be performed.

[0069]

As is apparent from the above description, according to the structure of the first aspect of the present invention, when the pedaling force of the driver is equal to or greater than the predetermined value determined by the urging force of the urging means, the pedal arm is operated by the driver. Even if the pedal is depressed, the pivoting member does not receive an excessive stress, so that the ratio of the amount of elastic deformation of the pivoting member to the pedaling force can be increased to improve the detection accuracy of the pedaling force detection device.

According to the second aspect of the present invention, the connecting pin is inserted into the hole provided in the pedal arm, and when the driver's treading force is equal to or more than a predetermined value, the connecting pin comes into contact with the wall surface of the hole, so that the pedal is pressed. Because it receives force directly from the arm,
When the driver's treading force is equal to or more than a predetermined value, the force can be reliably transmitted from the pedal arm to the push rod via the connecting pin.

[Brief description of the drawings]

FIG. 1 is a side view showing one embodiment of a brake pedal depression force detection device according to the present invention in a standard state where no depression force is applied.

FIG. 2 is an enlarged partial side view showing a part of a main part of the embodiment in a case where a pedaling force of a brake pedal is less than a predetermined value.

FIG. 3 is an illustrative plan sectional view showing the operation of the embodiment when the depression force of the brake pedal is less than a predetermined value.

FIG. 4 is an enlarged partial side view illustrating a main part of the embodiment in a case where the depression force of a brake pedal is equal to or more than a predetermined value, with a part of the main part being omitted;

FIG. 5 is an illustrative plan sectional view showing the operation of the embodiment when the depression force of the brake pedal is equal to or more than a predetermined value.

FIG. 6 is an explanatory diagram showing how to detect the amount of distortion of the pivoting member by the distortion sensor in the embodiment.

FIG. 7 is a block diagram showing an electric circuit for a strain sensor.

FIG. 8 is a graph showing the relationship between the depression force of a brake pedal and the amount of elastic deformation of a strain generating member for the conventional depression force detection device and the embodiment.

FIG. 9 is a graph showing a relationship between an output voltage Vout of a distortion sensor and a correction coefficient Ka.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Pedal arm 12 ... Brake pedal 20 ... Axis 22 ... Pivot member 24 ... Connection pin 26 ... Pin receiving hole 28 ... Clevis 30 ... Push rod 32 ... Compression coil spring 34 ... Adjustment device 36 ... Biasing force adjustment device 38 ... Position Adjustment device 56… Strain sensor

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuya Sasaki 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Zensaburo Higashito 3-5-5 Chofugaoka, Chofu City, Tokyo 1 share Inside the company Kyowa Dengyo

Claims (2)

[Claims] A brake device is provided which has a pedal arm pivotally supported by a support shaft and receives a driver's treading force at a position spaced from the support shaft, and which applies a force corresponding to the driver's treading force via a push rod. An elastically deformable pivot member pivotally supported by the pedal arm by a pivot substantially parallel to the support shaft, at a position spaced from the pivot; A connecting pin connecting the pivot member to one end of the push rod, and urging the pivot member about the pivot relative to the pedal arm in a direction to press the push rod toward the braking device. Biasing means, relative position setting means for setting a relative position of the pivot member about the pivot axis with respect to the pedal arm such that the connection pin is spaced from the pedal arm, and Detecting means for detecting the amount of elastic deformation of the member, wherein when the driver's treading force is equal to or greater than a predetermined value determined by the urging force of the urging means, the pivoting member opposes the urging force of the urging means. Wherein the connecting pin abuts on the pedal arm and receives a direct force from the pedal arm. 2. The pedal arm has a hole for receiving the connection pin in a loosely fitted state, and when the driver's treading force is less than the predetermined value, the connection pin is separated from the wall surface of the hole, and The pedaling force detecting device according to claim 1, wherein when the pedaling force of the driver is equal to or more than the predetermined value, the connecting pin receives a direct force from the pedal arm by coming into contact with a wall surface of the hole.