CN201063050Y - A Microwear Measuring Device for a Charged Friction Pair - Google Patents

Abstract

The utility model provides a micro-abrasion measuring device for a live friction pair, which is composed of a cantilever arm, a lever loading system, a live friction mechanism and a detection output mechanism. The upper end of the cantilever arm is fixed on the frame through the pin shaft, and the workpiece to be worn is installed on the working surface of the lower part; the lever loading system is composed of a balance bar, a counterweight and a weight; the live friction mechanism is composed of a grinding piece, a contact , ammeter, adjustable resistance and DC stabilized power supply are connected in series in sequence, and the charged friction mechanism forms a current loop through the wire and the workpiece to be worn; the detection output mechanism includes a displacement sensor and a computer. The utility model adopts computer control and processing technology, thereby eliminating the interference of human factors and improving the accuracy and speed of detection; in addition, the utility model has simple structure and convenient operation, and can be widely used in the evaluation of the wear resistance of brush materials, commutation In the field of measuring the micro-wear of friction pairs in the micro-electrical environment, such as the evaluation of electrical sliding contact wear performance of device materials.

Description

A Microwear Measuring Device for a Charged Friction Pair

technical field

The utility model relates to a detection device, in particular to a device for detecting the micro-abrasion of a friction pair in a charged environment.

Background technique

In engineering, the parts that perform relative motion and have mutual friction and wear are collectively referred to as friction pairs. The second element of the friction pair should be studied by the method of systematic analysis, so as to solve a series of phenomena that occur between the friction pair. For example, DC micro motors generally use the sliding contact between the commutator and the brush to realize power transmission and maintain the operation of the motor. When the commutator is working, it is in the state of sliding electrical contact with weak current, and its working current is usually less than 1A. The commutator and brush materials The wear performance of the electrical sliding contact has a decisive influence on the stability and service life of the motor. Only when the brush and the commutator maintain a good sliding contact can the normal operation of the motor be guaranteed; and this sliding contact will cause wear of the brush and the commutator, so the brush and the commutator are a pair of friction pairs . When the friction pair wears to a certain extent, it will cause accidents such as short circuit or crash. Therefore, the wear resistance of commutator materials and brush materials under the condition of electric sliding contact has a decisive influence on the stability and service life of the motor. The commutator and brushes are in the state of sliding electrical contact with weak current when they work, but there are few researches on the micro-wear phenomenon of the friction pair under the sliding electrical contact of weak current, and there are even fewer instruments and equipment used to measure the amount of wear.

Utility model content

In view of the above-mentioned deficiencies in the prior art, the purpose of this utility model is to provide a device for measuring the amount of wear of friction parts under weak current conditions.

The purpose of this utility model is achieved as follows: a micro-wear measurement device for live friction pairs, characterized in that it consists of a cantilever arm, a lever loading system, a live friction mechanism and a detection output mechanism;

The upper end of the cantilever arm is fixed on the frame through the pin shaft, and the workpiece to be worn is installed on the working surface of the lower part. With insulation board;

The lever loading system consists of a balance bar, a counterweight and a weight. One end of the balance bar is fixedly connected to the counterweight, and the other end is suspended from the weight; the cantilever arm is movably connected to the middle of the balance bar through a pin;

The electrified friction mechanism is composed of grinding parts, contacts, ammeters, adjustable resistors and DC power supplies connected in series in sequence. The live friction mechanism forms a current loop with the worn parts through wires; It is located on the side of the cantilever arm where the workpiece to be ground is fixed, and the grinding piece is fixed from the axial direction by the active insulating shaft and the driven insulating shaft, and the active insulating shaft is connected with the motor through a torsion spring. The cylindrical surface of the grinding part is in contact with the workpiece, and its side is in contact with the contact;

The detection output mechanism includes a displacement sensor, a signal processing system and a computer, and the displacement sensor is connected to the computer through a voltage amplifier, a low-pass filter, an A/D converter and a single-chip microcomputer;

The detection output mechanism is arranged on one side of the cantilever arm and is opposite to the workpiece to be worn.

The utility model is suitable for measuring the micro-abrasion amount of a friction contact part under a weak current working condition. Computer control and processing technology are adopted, thereby reducing the interference of human factors and improving the accuracy and speed of detection; in addition, the utility model has simple structure and convenient operation, and can be widely used in the evaluation of the wear resistance of brush materials and the evaluation of commutator materials. The field of measuring the micro-wear of the friction pair in the weak current environment, such as the evaluation of the wear performance of the electric sliding contact.

Description of drawings

Fig. 1 is the structural representation of the utility model;

FIG. 2 is a side view of FIG. 1 .

In the figure, 1-weight, 2-balance bar, 3-pin shaft, 4-counterweight, 5-pair of grinding parts, 6-contact, 7-wire, 8-ammeter, 9-adjustable resistance, 10 -DC power supply, 11-displacement sensor, 12-voltage amplifier, 13-low-pass filter, 14-A/D converter, 15-single-chip microcomputer, 16-computer, 17-wear parts, 18-insulation board, 19-insulation pressing piece, 20-cantilever arm, 21-motor, 22-torsion spring, 23-active insulating shaft, 24-driven insulating shaft.

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment, the utility model is further described.

Referring to Fig. 1 and Fig. 2, the micro-abrasion measurement device of the live friction pair involved in the utility model is composed of a cantilever arm 20, a lever loading system, a live friction mechanism and a detection output mechanism.

The upper end of the cantilever arm 20 is fixed on the frame (omitted in the figure) through the pin shaft 3, and the workpiece 17 to be worn is installed on the working surface of its lower part, and the workpiece 17 to be worn is fixed on the cantilever arm 20 through the insulating pressing piece 19 and the insulating plate 18. On one side of the lower part, there is an insulating plate 18 between the worn part 17 and the cantilever arm 20 .

The lever loading system is composed of a balance bar 2, a counterweight 4 and a weight 1. One end of the balance bar 2 is fixedly connected to a counterweight 4, and the other end is suspended with a weight 1. The cantilever arm 20 is movably connected to the balance bar through a pin 3. The middle part of the rod 2; the function of the lever loading system is to apply a certain load between the grinding part 5 and the worn part 17.

The electrified friction mechanism is composed of the grinding piece 5, the contact 6, the ammeter 8, the adjustable resistance 9 and the DC power supply 10 in series, and the live friction mechanism forms a current circuit through the wire 7 and the worn piece 17; the grinding piece 5 is a cylindrical structure, and is horizontally arranged on the side of the bottom of the cantilever arm 20 on which the workpiece 17 is fixed, and its axial direction is fixed by the active insulating shaft 23 and the driven insulating shaft 24 and driven by the driving shaft. The torsion spring 22 is connected with the motor 21; the driven insulating shaft 24 plays an auxiliary positioning role; the cylindrical surface of the grinding part 5 is in contact with the workpiece 17, and the side of the grinding part 5 is in contact with the contact 6.

The detection output mechanism includes a displacement sensor 11 , a signal processing system and a computer 16 , and the displacement sensor 11 is connected to the computer 16 through a voltage amplifier 12 , a low-pass filter 13 , an A/D converter 14 and a single-chip microcomputer 15 . The detection output mechanism is arranged on the other side of the cantilever arm 20 and is opposite to the workpiece 17 to be worn.

When measuring the micro-wear of the friction pair formed by the commutator and the brush, the brush material is generally used for the worn part 17, and the commutator material is used for the worn part 5. After the worn part 17 and the counter worn part 5 are installed, turn on the DC stabilized power supply 10, a weak electric field will be formed on both sides of the friction pair, and then start the motor 21 to wear the friction pair elements under the weak current state. During the wear process, the displacement sensor 11 amplifies the detected wear depth change (i.e. the change signal) through the voltage amplifier 12 and filters it with the low-pass filter 13, and the wear scar depth is obtained by the A/D converter 14 and the single-chip microcomputer 15. The data is input into the computer 16, so as to obtain the dynamic change data of the wear scar depth on the sample surface with time.

After the test, the computer substitutes the wear volume calculation formula according to the measured wear scar width and wear scar length:

wear volume $V=[\frac{{\mathrm{\πR}}^2}{180}\&Center\; Dot;\arcsin \left(\frac{b}{2R}\right)-\frac{b}{2}\sqrt{R^2-{\left(\frac{b}{2}\right)}^2}]\·L$

Among them: b is the width of the wear scar; L is the length of the wear scar; R is the radius of the grinding part.

Then according to the density of the sample material, its wear amount can be calculated.

In addition, by adjusting the resistance value of the adjustable resistor 9, the magnitude of the voltage drop at both ends of the friction contact can be changed, so as to achieve the purpose of adjusting the current intensity.

The utility model is suitable for the measurement of the micro-abrasion of friction contact parts under weak current working conditions. When measuring, install the worn part and the counter worn part, turn on the DC stabilized voltage power supply, form a weak electric field on both sides of the friction pair, and then start the motor The wear measurement of the friction part under the live working condition can be carried out.

Claims (1)

1. a charged friction pair wiping measurement mechanism is characterized in that being made up of overarm arm, bar thick stick loading system, charged friction mechanism and detection output mechanism;

The upper end of overarm arm (20) is fixed on the frame by bearing pin (3), install on the workplace of its underpart by mill part (17), be fixed on insulation compressing tablet (19) on the side of overarm arm (20) bottom by mill part (17), quilt is ground between part (17) and the overarm arm (20) is provided with insulcrete (18);

Bar thick stick loading system is made up of balance stem (2), balancing weight (4) and counterweight (1), the balance stem fixedly connected balancing weights of (2) one ends (4), other end suspention counterweight (1); Overarm arm (20) is movably connected on the middle part of balance stem (2) by bearing pin (3);

Charged friction mechanism is by being connected in series successively to mill part (5), contact (6), reometer (8), adjustable resistance (9) and D.C. regulated power supply (10), and charged friction mechanism constitutes current return by lead (7) and quilt mill part (17); To mill part (5) is cylindrical structure, and laterally be located at the overarm arm (20) be fixed with by the mill part (17) a side, by initiatively insulation axle (23) and driven insulation axle (24) is from axially fixing, initiatively insulation axle (23) is connected with motor (21) by torsionspring (22) to mill part (5); The face of cylinder to mill part (5) is contacted with grinding part (17), and the side of grinding part (5) is contacted with contact;

Detect output mechanism and comprise displacement transducer (11) and computing machine (16), displacement transducer (11) is connected to computing machine (16) by voltage amplifier (12), low-pass filter (13), A/D converter (14) and single-chip microcomputer (15);

Detect output mechanism and be located at a side of overarm arm (20), and with relative by mill part (17).

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