SU1385029A1 - Installation for determining rest friction coefficient of materials - Google Patents

Description

(21) 4138371 / 25-28

(22) 10/21/86

(46) 03/30/88. Bksh. № 12

(71) Kuibyshev Aviation Institute. Acad. S.P.Koroleva.

(72) V.A. Barvinok, P.A. Bordakov, S.F. Demichev, O.V. Kuprin, V.I. Lyubimov and D.V.Samorodov

(53) 620.178.16 (088.8)

(56) Igoshin V.A., Chersky I.N. Installation for the study of transients. - In the book. : Problems of friction and wear. Kiev, 1977, issue 11, pp.37-39.

(54) INSTALLATION FOR DETERMINATION OF THE COEFFICIENT OF FRICTION REST OF MATERIALS

(57) The invention relates to a test technique and can be used in mechanical engineering to determine the coefficient of rest

in pairs operating under vacuum conditions. The aim of the invention is to simplify the design, reduce test time, and expand the operational capabilities of the installation by combining in one mechanism FUNCTIONS the relative movement of the sample and counter piece and their normal loading, leading to the refrigerant bimetallic plate, and placing the installation in a vacuum chamber. By heating the bimetallic plate 6 by the heater 5 through the latch 7 and the contra-sample 2 to the sample 3, rigidly fastened by the clamp 9 with the measuring plate 8, a shearing force is transmitted, which is recorded with the help of strain gauges and measuring instruments. The normal load on the sample and the contra sample cos is given by the force P on the bimetallic plate. The vacuum density and mobility of the input of the bimetallic plate into the chamber is ensured by a syphonic entry of 5, 2 Cp. f-ly. 2 Il.

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The invention relates to a test technique and can be used in mechanical engineering to determine the rest friction coefficient in pairs operating under vacuum conditions.

The aim of the invention is to simplify the design by combining the functions of the normal position and relative displacement in one mechanism, reducing the test time by accelerating the bimetallic plate to its initial position after the test, as well as expanding the operational capabilities of the installation by providing for testing in vacuum.

1 shows an installation for

thirty

35

determination of the friction coefficient of rest 20 Further increase in the temperature of materials in a vacuum; in fig. 2 - section A-A on fig.1.

The device contains a vacuum chamber 1, a mechanism for normal loading and relative movement 25 of the counter-sample 2 and sample 3, made in the form of a bracket 4 installed in the vacuum chamber 1, and a bimetallic plate 6j located inside the heater 5 hinged on it with the latch 7 contrasing 2 and have a plane of greater rigidity in the same plane with the plane of greater rigidity of the measuring plate 8 and normal to the contact surface of the contrashing 2 and sample 3, rigidly "fixed of a clamp assembly 9 on the measuring plate 8, strong fonny input 10 into the vacuum chamber 1, Q wherein bimetallic plate 6 is fixed, and recording apparatus (not shown).

The device works as follows.

Sample 3 and contra sample 2 of the test friction pair are fixed in clamp assembly 9 and clamp 7, the vacuum chamber 1 is sealed and evacuated. Upon reaching the required residual pressure in the chamber, the friction pair is loaded with a normal load, for which a bimetallic plate

45

50

the force of the friction-rest force increases by the shearing force and the micro-shift of the contra-sample 2 takes place relative to sample 3. The resulting bending forces in the measuring plate 8 are equal in absolute value to the force of friction in the contact pair. These flexural forces are recorded by strain gauges and measuring instruments. The vacuum density and mobility of introducing the bimetallic plate into the chamber is provided by the bellows entry 10. For quickly returning the heated bimetallic plate to its initial position through the special channels 11, the refrigerant is passed.

Claims (2)

1. An installation for determining the friction coefficient of the material, holding the case, located in the normal loading and relative displacement mechanisms of the contraction sample and the sample, the contra-clamp retainer, the measuring plate, the specimen clamping unit connected to it, the booster and recording equipment that so that, in order to simplify the construction, the mechanism of normal loading and relative movement of the counterpiece and the sample is made in the form of a bracket mounted in the case and hinged on it and placed bimetal plate inside the heater, which is connected to the counterpiece fixer and has The force of P.-Osseatelles is applied to the samples by heating the bimetallic plate 6 with the help of heater 5. When heated, due to the difference in thermal linear expansion coefficient of the bimetal, a bending moment occurs in plate 6 causing the contact between sample 3 and counterpiece 2 - shifting force. G, by increasing the heating temperature of the bimetallic plate 6, the bending moment and, consequently, the shear force in the contact pair increases and at a certain threshold value of the temperature the magnitude of the shear force becomes equal to the force of rest peace. In the process of heating of the bimetallic plate 6 from the initial temperature to the threshold value, a micro-shift of the counterpiece 2 with respect to sample 3 occurs within the preliminary displacement. thirty five 20 Further increase in temperature 25 Q five 0 the force of the friction resting force causes the shear force to exceed and the microswitch of counterpiece 2 with respect to sample 3 occurs. The bending forces arising in this case in the measuring plate 8 are equal in absolute value to the force of friction in the contact pair. These flexural forces are recorded by strain gauges and instrumentation. The vacuum density and mobility of introducing the bimetallic plate into the chamber is provided by the bellows entry 10. For quickly returning the heated bimetallic plate to its initial position, a coolant is passed through it through special channels 11. Invention Formula 1. An installation for determining the coefficient of friction of materials for rest, comprising a housing, mechanisms for normal loading and relative movement of the counterpiece and the sample, a counterpiece, a measuring plate, a specimen clamping unit, a heater, and a recording apparatus, that, in order to simplify the design, the mechanism of normal loading and relative movement of the contra-sample and the sample is made in the form of a bracket mounted in the case and hinged and therein and a heater disposed inside the bimetallic strip associated with the clamp and available kontrobraztsa the plane of greater rigidity in the same plane with the plane of greater rigidity of the measuring plate and normal to the contact surface of the sample and counterpiece. 2. Installation under item 1, about tl and h ayi with the fact that, in order to reduce the test time by reducing the thermal inertness of the bimetallic plate, in the plate coolant circulation channels are filled. 3. Installation according to claim 1, so that in order to expand the operational capabilities by conducting tests in a vacuoze, the housing is made in the form of a vacuum chamber with a bellows input, in which a bimetallic plate is fixed. eleven FIG. 2