JPH0588412B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a pedal force detection device for detecting a pedal force applied to a vehicle operating pedal such as a brake pedal, clutch pedal, or accelerator pedal.
The pedal force detection device of the present invention can be used for testing the feeling of pedal operation, testing the braking force of a braking device, and as a sensor for an anti-skid braking device.

[Prior art]

When designing an automobile, it is necessary to test the feeling of pedal operation and the braking force of a braking device, and in this case, it is necessary to measure the pedal force applied to the pedal. Conventionally, in this type of test, the pedal force has been measured by attaching a measuring device called a pedal force meter to the pedal of a brake or the like, or by connecting a pressure sensor to the hydraulic piping in the case of testing hydraulic brakes.

In the latter method, it is necessary to convert the measured hydraulic pressure into pedal force, and therefore it is necessary to measure the relationship between hydraulic pressure and pedal force in advance.
Furthermore, it is not easy to attach the pressure sensor to the hydraulic piping, and it takes a lot of time and effort to detect the pedal force.

In the former method, a general-purpose pedal force meter commercially available from Kyowa Dengyo and others is generally used. This tread force meter has a square-shaped main body that is bolted to an automobile pedal, and an X-shaped flexible member to which a strain gauge is attached is deformably supported inside the main body. A cylindrical treading member is fitted into the square-shaped main body in a nested manner. This treading member is seated on an X-shaped flexible member, and when the tester steps on the treading member, the flexible member flexes, and the strain is detected by a strain gauge.

Since this tread force meter has a considerable thickness in the longitudinal direction, when attached to a brake pedal or the like, the tread surface of the tread force meter will be at a different position from the actual tread surface of the pedal. For this reason, the feeling of pedal operation is significantly different from the feeling of an actual automobile, and it has been difficult to perform a pedal operation feeling test while detecting the pedal force.

Generally, when the pedal is depressed, the pedal moves in an arc around the pivot of the brake lever, etc. to which it is attached, and the angle formed by the center surface of the pedal with respect to the direction of the driver's pedal force is the stroke. However, in the pedal force meter, the pressure member can only move in a direction perpendicular to the center plane of the pedal, and since the pressure surface of the pressure member is flat, the pressure increases as the pedal is depressed. The axis of the member will be deviated from the direction in which the pedal force is applied. For this reason, it has been impossible to accurately measure the pedal effort.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a pedal force detection device that has an operation feeling close to an actual pedal operation feeling and is capable of detecting pedal depression force with high accuracy.

[Means for solving problems]

The pedal force detection device of the present invention includes one pressure receiving plate and two detection sections. Respective detectors are located on each side of the vehicle pedal.

Each detection section includes a rigid central mounting section that can be detachably attached to the side of the pedal, a pair of flexible members extending vertically from the mounting section, and an input section provided at the free end of each flexible member. The flexible member is provided with a strain gauge.

The flexible member and the pressure plate are curved along the curved tread surface of the automobile pedal, and the pressure plate is supported by the input section.

[Effect]

The pedal force applied to the pressure receiving plate is distributed to the two detection sections, and transmitted to the input section of each detection section to deform the flexible member. Strain generated in the flexible member is detected by a strain gauge.

〔Example〕

Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 and FIG. 2 are a partially cutaway side view and a partially cutaway front view, respectively, showing a pedal force detecting device of the present invention attached to a brake pedal of a vehicle. Needless to say, this device can also be used by attaching it to a clutch pedal, accelerator pedal, etc.

A brake pedal 12 is individually attached to a foot brake lever 10 of a vehicle, and as is well known, the tread surface 14 of this pedal 12 is curved to improve the feeling when operating the pedal. This pedal 12
The pedal force detection device 16 of the present invention is attached to the pedal.

The pedal force detecting device 16 includes two detecting sections 18, each detecting section 18 on both sides 2 of the pedal 12.
It is located at 0,22. These two detection units 18
are symmetrical to each other, so only one will be explained.

As shown in FIG. 3, the detection section 18 includes a central mounting section 24 and flexible members 2 extending vertically from the central mounting section 24.
6, 28 and input sections 30, 32 provided at their tips.
and four strain gauges 34 (only one of which is shown in FIG. 3) attached to the front and back sides of the flexible member. The central mounting portion 24 has great rigidity and is provided with a groove 36 of the same curvature as the pedal 12. Two screw holes are provided in the rear wall 38 of this mounting portion 24, and after fitting the groove 36 and the pedal side portion 20, a socket bolt 40 or the like is screwed into the screw hole as shown in FIG. By doing so, the detection unit 1
8 is attached to the pedal 12.

A flexible member 2 extending vertically from the central mounting portion 24
The wall thicknesses of 6 and 28 are relatively thin so that they exhibit flexibility. These flexible members 26,
28 is curved concentrically with the tread surface 14 of the pedal 12. Strain gauges 34 are provided on the front and back sides of each of the flexible members 26 and 28 in the vicinity of the central attachment portion 24.
The strain gauge 34 is a known strain gauge, and a foil gauge or a semiconductor gauge can be used. Input section 3
0 and 32 are provided with screw holes 42 and 44.

The detection device 16 further includes a pressure receiving plate 46,
This pressure receiving plate 46 has an approximately square outline. The pressure receiving plate 46 is also curved concentrically with the pedal tread surface 14. After attaching the two detection parts 18 to the left and right side parts 20, 22 of the pedal 12, by screwing the screws 48 arranged at the four corners of the pressure receiving plate 46 into the screw holes 42, 44 of each input part 30, 32. , the two detection units 18 and the pressure receiving plate 46 are coupled. It is preferable to provide a rubber pad 50 having a shape close to that of the pedal 12 on the surface of the pressure receiving plate 46. This rubber pad 50 is made of the same material as a normal pedal pad, and is attached to the surface of the pressure receiving plate 50 by adhesive or the like. This rubber pad is intended to give the same operating feel as a normal pedal.

If a stopper 54 is attached to the upper part of the pressure receiving plate 46 with a screw 52 or the like, it is possible to prevent the detection device 16 from falling off the pedal 12 even if the socket bolt 40 becomes slack.

When using this pedal force detection device, after the device 16 is attached to the pedal 12 as described above, eight strain gauges 34 are connected to form a bridge circuit as shown in FIG. 4. This bridge circuit is a known one, in which two gauges, which are placed on the front side of the flexible members 26 and 28 and receive a tensile force, are connected to the same side of the bridge circuit, and two gauges, which are placed on the back side of the flexible members and receive a compressive force, are connected to the same side of the bridge circuit. Gauges are connected to adjacent edges. That is, on the opposite side of the bridge circuit, strain gauges that receive forces of the same nature are placed. Moreover, the reason why strain gauges are provided on the front and back of each flexible member is to eliminate distortion due to vertical force and torsion.

As shown in FIG. 4, a reference voltage E is applied to terminals A-B.

When the pedal 12 is depressed, a pedal force F is applied to the rubber pad 50, and the pressure is applied to the input section 3 via the pressure receiving plate 46.
0,32. Since the pressure receiving plate 46 is attached to the input parts 30 and 32 at the four corners, when the center of the rubber pad 50 is stepped on, each input part receives 1/2 pressure.
A force of 4.F will be transmitted. Each bending member is bent by this force, and an output power e corresponding to the amount of strain is obtained between terminals C and D of the bridge circuit due to a change in the resistance of the strain gauge. If the point of application of the pedal force deviates from the center of the rubber pad 50, the strain amount of each strain gauge will take a different value, but if the bridge circuit shown in FIG. 4 is configured, the output voltage e corresponding to the pedal force F can be Obtainable.

When using this pedal force detection device 16 for a feeling test during pedal operation, the obtained output voltage e is amplified by a known amplifier and output to a digital analog meter, and the stroke of the pedal 12 is also known. It is possible to evaluate the pedal by measuring it with a potentiometer, etc., and drawing the pedal force and stroke characteristics with a pen recorder, etc.

Further, in the anti-skid brake device, this output voltage e corresponding to the pedal force F can be used as an anti-skid control signal.

In the embodiment described above, the detection section 18 has been described as being attached to both the left and right sides of the pedal, but it goes without saying that it can be attached to the sides of the pedal in the vertical direction.

Furthermore, although the flexible members 26 and 28 and the pressure receiving plate 46 have been described as having curved surfaces concentric with the pedal tread surface 14, they can also have a curvature comparable to that of the tread surface 14.

Furthermore, the pressure receiving plate 46 and the input part 3 are connected by screws 48.
0 and 32, a bushing or the like is used to prevent the head of the screw 48 from directly compressing the pressure receiving plate 46, and between the hole in the pressure receiving plate that receives the bushing and the bush. By providing some clearance, the output voltage e can be increased. In this way, since the pressure receiving plate 46 and the input sections 30, 32 slide along the contact surface perpendicular to the direction of the pedal force F, only the force in the direction of the pedal pressure is transmitted to the detection section 18, and the amount of distortion of the flexible member is This is because it is large.

〔Effect of the invention〕

In this way, each flexible member is curved along the tread surface of the pedal, so the thickness of the device in the longitudinal direction is significantly reduced compared to conventional pedal dynamometers in which the flexible members extend straight within the same plane. , it becomes possible to bring the pressure receiving plate closer to the pedal. For this reason, the pedal operation feeling when the pedal force detection device is attached is close to the feeling when the device is not attached.

In addition, since the pressure receiving plate is also curved to match the pedal tread surface, the operating feeling approaches the operating feeling of the actual pedal, and even if the pedal travel increases, the pedal force can be transmitted to the flexible member more accurately, allowing measurement. Improves accuracy.

Furthermore, since this detection device includes two detection sections 18 that are attached to both sides of the pedal, it can be easily attached to pedals with different widths. Therefore, many types of vehicles can be tested using the same device.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view showing the brake pedal attached to the pedal force detection device of the present invention;
FIG. 2 is a partially cutaway side view of the device, FIG. 3 is a perspective view of the detection section, and FIG. 4 is a diaphragm of the bridge circuit. 12...brake pedal, 14...tread surface, 16...treading force detection device, 18...detection section, 24...center mounting section,
26, 28... Flexible member, 30, 32... Input section, 3
4...Strain gauge, 46...Pressure plate, 50...Rubber pad.

Claims (1)

[Scope of Claims] 1. A device comprising: a pair of detection portions disposed on each side of a vehicle operation pedal; and one pressure receiving plate disposed in front of the pair of detection portions; The part includes a rigid central mounting part that can be detachably attached to a side part of the operation pedal, a pair of flexible members extending vertically from the mounting parts, a strain gauge provided on each of the flexible members, and a strain gauge provided on each of the flexible members. a pair of input parts provided at the upper and lower ends of a flexible member, the flexible member and the pressure receiving plate are curved along the curved tread surface of the operating pedal and substantially parallel to each other, and the pressure receiving plate is configured to detect 1. A depressing force detection device for a vehicle operation pedal, characterized in that the device is supported in a force transmission relationship to an input portion of a vehicle. 2. The pedaling force detection device according to claim 1, wherein a rubber pad is attached to the surface of the pressure receiving plate. 3. The pedaling force detection device according to claim 2, wherein the pressure receiving plate and the input section are slidably in contact with each other along a plane perpendicular to the direction in which the pedaling force acts.