JPS6250632A - Leg-power detector for operation pedal for vehicle - Google Patents

Abstract

PURPOSE:To detect the pedal leg-power of the operation feeling close to the actual pedal operation feeling with high accuracy by making a deflective member of a detection part or the like a curved form like a step plate of the operation pedal. CONSTITUTION:A leg-power detector fitted to a brake pedal or the like for a brake or the like is formed of the deflective members 26 and 28 at both sides of the central member 24 with rigidity of the detection part 18 and a pressure receiving plate or the like. This pressure receiving plate and the members 26, 28 and 24 and the like are made the curved form running almost parallel along a curve of the operation pedal of the brake pedal and the operation feeling via a rubber pad 50 of the surface is made close to the operation feeling of the actual pedal. Accordingly, the pedal leg-power of the feeling close to the actual pedal operation feeling is detected with high accuracy via strain gages 34 of the surface and the back of the members 26 and 28.

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 operation pedal such as a brake pedal, a clutch pedal, or an accelerator pedal.

The pedal force detection device of the present invention can be used for a pedal operation feeling test, a braking force test for 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 inserted into the square-shaped main body and fitted into the pre-formed shape. 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 in 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 force.

[Purpose of the invention]

An object of the present invention is to provide a pedal force detection device that has an operation feeling close to the 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.

[For production]

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, an accelerator pedal, etc.

A brake pedal 1 is attached to a foot brake lever 10 of the vehicle.
2 is fixed, and as is well known, the tread surface 1 of this pedal 12
4 is curved to improve the feeling when operating the pedals. This pedal 12 has a pedal force detection device 16 according to the present invention.
is installed.

The pedal force detection device 16 includes two detection sections 18, each of which is arranged on both sides 20, 22 of the pedal 12. Since these two detection units 18 are symmetrical to each other, only one will be described.

As shown in FIG. 3, the detection section 18 includes a central mounting section 24,
Flexible members 26 and 28 extend vertically from there, input sections 30 and 32 are provided at the tips of the flexible members, and four strain gauges 34 are attached to the front and back sides of the flexible members (only one of which is shown in Figure 3). (as shown). Central mounting part 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 the groove 36 and the pedal side portion 20 are fitted, a socket bolt 40 is inserted into the screw hole as shown in FIG.
The detecting section 18 is attached to the pedal 12 by screwing the detecting section 18 into the pedal 12.

The wall thickness of the flexible members 26 and 28 extending vertically from the central mounting portion 24 is relatively thin so as to exhibit flexibility. These flexures 26 , 28 are curved concentrically with the tread surface 14 of the pedal 12 . Strain gauges 34 are provided on the front and back sides of each flexible member 26, 28 near the central mounting portion 24. The strain gauge 34 is a known strain gauge, and a foil gauge or a semiconductor gauge can be used. The input portion 30° 32 is provided with punch holes 42,44.

The detection device 16 further comprises a pressure plate 46, which has an approximately square contour. The pressure receiving plate 46 is also curved concentrically with the pedal tread surface 14. After attaching the two detection sections 18 to the left and right sides 20.22 of the pedal 12, screw the screws 48 placed at the four corners of the pressure receiving plate 46 into each input section 30.
By screwing into the threaded holes 42 and 44 of 32, the two detection parts 18 and the pressure receiving plate 46 are combined. It is preferable to provide a rubber pad 50 having a shape similar 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 operating feel of a normal pedal pad.

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

When using this pedal force detection device, after attaching the device 16 to the pedal 12 as described above, the eight strain gauges 34
A bridge circuit shown in FIG. 4 is constructed by connecting the two. This bridge circuit is known in the art, with two gauges on the front side of the flexible member 26, 28 receiving a tensile force connected to the same side of the bridge circuit, and two gauges on the back side of the flexible member receiving a compressive force connected to the same side of the bridge circuit. Gauges are connected to adjacent edges. That is, strain gauges that receive forces of the same nature are placed on opposite sides of the bridge circuit. 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 tearing.

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 is transmitted to the input portions 30 and 32 via the pressure receiving plate 46. Since the pressure receiving plate 46 is attached to the input parts 30, 32 at the four corners, when the center of the rubber pad 50 is stepped on, a force of -.F will be transmitted to each input part. 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. The point of application of pedal force is the rubber pad 50
deviates from the center, the strain amount of each strain gauge takes a different value, but if the bridge circuit shown in FIG. 4 is constructed, an output voltage e corresponding to the pedal force F can be obtained.

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 The pedal can be evaluated by measuring with a known potentiometer or the like, and by drawing the pedal force and stroke characteristics with a pen recorder or the like.

In addition, in the anti-skid brake device, the pedal force F
This output voltage e corresponding to 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.

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

Furthermore, the pressure receiving plate 46 and the input part 30, 32 are connected by screws 48.
Instead of firmly fixing the screws 4 and 4, use a bushing etc.
The output voltage e can be increased by preventing the head of the pressure receiving plate 46 from directly compressing the pressure receiving plate 46 and providing a slight clearance between the hole in the pressure receiving plate that receives the bushing and the bushing. In this way, since the pressure receiving plate 46 and the input section 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 becomes larger.

〔Effect of the invention〕

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

In addition, since the pressure receiving plate is also curved to match the pedal tread surface, the operating feeling is closer to that of an actual pedal, and even if the pedal travel distance increases, the pedal force can be more accurately transmitted to the flexure member. This improves measurement 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 pedal force detection device of the present invention attached to a brake pedal, Fig. 2 is a partially cutaway side view of the device, and Fig. 3 is a perspective view of the detection section. Fourth
The figure shows a diaphragm of a bridge circuit. 12... Brake pedal, 14... Tread surface, 16...
- Pedal force detection device, 18... detection section, 24... central mounting section, 26.28... flexible member, 30, 32.
...Input section, 34...Strain gauge, 46...
Pressure receiving plate, 50...Rubber pad. Figure 2

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 detection unit includes a rigid central mounting part that can be detachably attached to a side of the operating pedal, a pair of flexible members extending vertically from the mounting parts, and a strain gauge provided on each of the flexible members. a pair of input parts provided at the upper and lower ends of the flexible member, the flexible member and the pressure receiving plate are curved along the curved tread surface of the operation pedal and substantially parallel to each other, and the pressure receiving plate is 1. A pedal force detection device for a vehicle operating pedal, characterized in that the device is supported in a force transmission relationship to an input portion of a detection portion. 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.