CN2035880U - Measuring device for footrest force - Google Patents

Abstract

The utility model provides a measuring device for footrest force which is suitable for measuring the foot force of a brake pedal of an automobile and the foot force of other machines, comprising a foot force sensor and a digital display instrument. The foot force sensor is provided with a guide post type guiding device which is composed of a rolling guiding structure or a sliding guiding structure. The bearing area of the foot force sensor is large, so the influence of eccentric load is eliminated, and the foot force sensor can be positioned slantwise for measuring. The digital display instrument is provided with a sampling and keeping circuit and a digital latch circuit; the maximum value of the foot force being measured can be automatically and permanently kept on a display board. The utility model has the advantages of compact structure, convenient operation, easy fabrication and sensitive reaction; each precision index can meet test requirement.

Description

Measuring device for footrest force

The utility model relates to a kind of testing tool of brake system of car grade estimation, is applicable to that the legpower value to brake pedal is measured in brake system of car stand, the actual road test, also can be used for other mechanical pedal force and measures.

At present, each big automobile production state of the world as the U.S., Japan, West Germany, the Soviet Union etc., considers from the aspects such as comfortableness of safety, reliability and the driving of car steering, all the legpower index of auto pedal, classifies the big event of car mass examination as.And various types of Brake Pedal Force Tester devices have been developed, have produced.Department of China government concerned also lists the index of pedal force in the important indicator of the automobile brake perfrmance detection of one of important evaluation project in the grade estimation way of passenger vehicle car, offroad vehicle and the cargo vehicle of promulgation in 1985～1987 years.It is the prerequisite of carrying out brake system of car grade estimation.But before this, China does not also have a Brake Pedal Force Tester that designs voluntarily, makes to serve society, and this quasi-instrument of import then needs a large amount of foreign exchanges.Therefore, each car mass of China is monitored department and factory now, and one or two unit has the import instrument except that minority, major part does not possess this kind measurement means, just, do some, can't obtain the science index of this respect with reference to the property measurement with people's sensation or by some easy device.

The purpose of this utility model is that a kind of Brake Pedal Force Tester that is used for automobile brake pedal will be provided.It mainly is made up of pedaling force sensor and digital displaying meter, its pedaling force sensor requires can bear unbalance loading and get rid of the influence of unbalance loading to the vertical legpower of survey, bearing area is big, response speed is fast, either direction, angle are placed and all can be measured, the digital displaying meter decapacitation shows outside each instantaneous legpower value, can also show and keep maximum legpower value.

The purpose of this utility model is achieved in that in its sensor, adds a guide colume type guide piece on a pure bending beam type elastic body top of posting resistance strain gage, constitutes the novel sensor of tape guide.Guide piece is made up of the fastness of low-friction coefficient, form as paying by rolling friction, make friction force drop to minimum point to the influence of measuring accuracy, under the effect of guide piece, the bearing area of sensor is enlarged, and can be when being subjected to unbalance loading, only longitudinal loading is passed to elastic body, making it truly institute be surveyed vertical legpower converts electric signal to and flows to digital displaying meter, solved general pressure transducer the bearing area that can not accomplish big, eliminate problems such as unbalance loading influence, and can when tilting to place, similarly finish measuring task.In its digital displaying meter, design has a sampling, holding circuit, its function is the maximal value that can capture tested legpower in test process in time, and by the digital latch circuit in the digital displaying meter, after each off-test, maximum legpower value in this process is for good and all latched on display board, be convenient to experimenter's observation, record.

Describe concrete structure of the present utility model and working condition in detail below in conjunction with accompanying drawing.

The sensor of rolling guide frame is sensor a kind of with guide colume type guide piece.Fig. 1 is the sectional view of this sensor, and it is by pressure-bearing cap (1), guide pillar (2), and guide pin bushing (3) and ball (4) are formed targeting part.By power transmission ball (5), elastic body (6) and housing (7) are formed the converter part.Owing to adopt rolling friction to pay between the fastness of its targeting part, its friction factor is reduced greatly, improved measuring accuracy.When automobile brake, the operator steps down on the pressure-bearing cap of sensor, regardless of position, the direction of this pedal force, and act on acting force on the elastic body (6) by power transmission ball (5) by guide pillar (2), be all the time along perpendicular to the elastic body direction, act on the elastic body center.Make elastic body produce the pure bending distortion, power is changed into electric signal.And transverse component does not act on elastic body, does not influence elastic body power is changed into this process of electric signal.This scenario-frame compactness, processing technology is good, and every index such as measuring accuracy all can satisfy car mass evaluation requirement.

Fig. 2 is the another kind of structure with sensor of guide colume type guide piece, what adopt is the sliding sleeve guide frame, it is structurally most of identical with the rolling guide frame, different is to have designed a sliding sleeve (10) between guide pillar (8) and guide pin bushing (9), sliding sleeve adopts the engineering plastics of anti-attrition better performances to make, and is added with between fastness and contains M ₀S ₂Railway grease, its friction factor is reduced as far as possible.This sensor similarly has most of advantage of rolling guide frame, and just the influence of its friction force is slightly larger than the sensor of rolling guide frame.But its structure is more simple, and processing and manufacturing is more easy, so select for use this kind of more economical under the situation that does not influence service precision.

Fig. 3 samples in the digital displaying meter, the block diagram of holding circuit, one the peak-holding circuit that it is made up of half-wave rectifying circuit (11) analog signal storage electric capacity (12) and data buffer (13) three parts.Half-wave rectifying circuit is made up of voltage comparator and diode, and analog signal storage electric capacity is a high-quality electric capacity.Data buffer is the operational amplifier of a high input impedance.In test process, when input signal arrives, at first the voltage in signal voltage and the memory capacitance is compared by voltage comparator, as the signal voltage height, then voltage comparator is a noble potential, this moment, the output terminal by voltage comparator charged to memory capacitance through commutation diode, when capacitance voltage is elevated to when identical with signal voltage, the voltage comparator upset becomes low-voltage, utilize this moment the effect of the unidirectional conducting of diode to stop the backflow of capacitance charge effectively, the voltage in the electric capacity is remained on the maximal value of signal voltage.Owing to adopt the operational amplifier of high input impedance to bear data buffer, the electric charge that has reduced electric capacity leaks, and the sampling time was reached more than 30 seconds, and error is less than 3 ‰.

Fig. 4 is the block diagram of digital latch circuit, and it is made up of mimic channel and digital circuit.Digital circuit (14) is the A/D converter that can lock data, also can be other counter, and mimic channel is a voltage comparator (15), detection signal voltage at any time.When voltage is lower than a certain setting value of benchmark (16), illustrate that the pin of testing crew has left pedal, test finishes, and display circuit is blocked in voltage comparator upset at this moment, and the maximum legpower numerical value that shown this moment is for good and all stayed on the display board.

Claims (5)

1, a kind of Brake Pedal Force Tester device of being made up of pedaling force sensor and digital displaying meter, feature are that its pedaling force sensor has a guide colume type guide piece and its digital displaying meter has sampling, holding circuit and digital latch circuit.

2, by the described instrument of claim 1, feature be the guide colume type guide piece of its pedaling force sensor by guide pillar (2), guide pin bushing (3) and ball (4) composition.

3, by the described instrument of claim 1, feature is the guide colume type guide piece of its pedaling force sensor or by guide pillar (8), guide pin bushing (9) and sliding sleeve (10) composition.

4, by claim 1,2,3, described instrument, feature is the sampling in its digital displaying meter, and holding circuit is by half-wave rectifying circuit, and the peak-holding circuit that analog signal storage electric capacity and buffering amplifier are formed is born.

5, by claim 1,2,3,4, described instrument, feature is that the digital latch circuit in its digital displaying meter is made up of digital circuit and mimic channel two parts.

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