SU79212A1 - Instrument for studying the friction of fibrous materials - Google Patents

Description

Appliances using roller-type bearings in clamping devices are known. However, such devices do not provide uniform pressure distribution on the clamping planes and the required accuracy of the test results.

The subject of the invention is a device for studying the rubbing of fibrous materials, in which, in order to obtain an even distribution of the normal pressure on the clamps, one of the clamping planes of the device is n-turn on a ball support. The use of this support improves the accuracy of the test;

FIG. 1 shows a general view of the device; in fig. 2 is a side view of it; in fig. 3 view in plan.

The device has a detachable clip of two planes wrapped around cotton, leather, cloth or other material to be determined by the coefficient of friction. For example, the lower end of the staple of the fibrous material being tested and the upper end of the clamp are placed between the planes of the clamp.

One of the clamping planes of the device, which is one whole € 0 rack / (Fig. 1), is fixed on

60 Code Issue 2, part I, 1950

The bracket 2 mounted on the rod 9 of the dynamometer and the other is located at the end of the crank lever 3, which has a rotation on the pin 4 (Fig. 2). At the other end of the lever 3 suspended load. The dimensions of the instrument are calculated so that the normal pressure in the lower jaw is exactly equal to the load to be informed.

The second plane of the clamp, on the "snarling rod" 3, is designed as a protruding square pad 5 with a size of 1 cm. The pad has a bearing ball 6 and is held onto the lever with a pin. This device provides the friction surface constant and always creates pressure perpendicular. this surface, which, in turn, ensures uniform distribution of the normal pressure on the clamping planes.

To determine the coefficient of friction, for example, cotton by cotton, on the plane of the device clamping cotton clamps, which are held in a tensioned state on the planes with the help of specially arranged clamps 7, secured by wings 8. In the upper clamp of the dynamometer,

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one end of the test staple cotton. The fibers constituting this staple are filled between the planes of the detachable clamp of the device, after which the lever 3 is loaded according to the pressure at which the friction force is determined.

When shifting the shtalele relative to each other, the dynamometer will show "on the scale of force-friction between the staples at the moment of the start of the slide.

The friction coefficient (M) is determined by the formula:

where:, j Р-г-indication of the dynamometer g is the weight of the load suspended on the lever 3.

The subject of the invention A device for studying the friction of fibrous materials, consisting of two planes clamping a test specimen, one of which is located on a fixed stand, and the other on a pivoting crank lever, characterized in that in order to obtain a uniform distribution of normal pressure on the clamping planes, one of them made turning and ball-bearing.

FIG. 2

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