SU1219955A1 - Arrangement for recording slippage of pneumatic tyre tread with respect to bearing surface - Google Patents

Abstract

The invention relates to devices for studying the processes of interaction of a pneumatic tire with a support surface. The purpose of the invention is to improve the accuracy of the measurement. nor by making it possible to register the direction of slippage. On the housing 1 a support platform 2 is installed with a socket 3 in which the sensitive element 4 with a spherical working surface is placed. The sensing element 4 is rigidly mounted on a horizontal axis 5 connected to the movable contact 6 of the circular potentiometer 7. The horizontal axis 5 is mounted on the frame 8 in the supports 9. The frame 8 is equipped with a stand 10 installed in the housing 1 with the possibility of rotation around the vertical axis. The rack 10 of the frame 8 is connected to the movable contact 11. circular potentiometer 12. 2 ill. (Ls

Description

one

The invention relates to the field of transport engineering, in particular, to devices for studying the processes of interaction of a pneumatic tire with a support surface.

The purpose of the invention is to increase the measurement fineness by making it possible to register the direction of slip.

Fig. 1 is a schematic diagram of the device; in Fig.2, view A in Fig.1.

The device comprises a supporting platform 2 mounted on the housing 1 with a socket 3 in which the sensitive element 4 with a spherical working surface is placed. The sensing element 4 is rigidly mounted on a horizontal axis 5 connected to the movable contact 6 of the circular potentiometer 7 for measuring the amount of slip. The horizontal axis 5 is mounted on the frame 8 in the supports 9. The frame 8 is equipped with a stand 10 installed in the housing 1 with the possibility of rotating it around the vertical axis z -Z, shifted in the vertical plane relative to the center of the sensitive element (point O) of the vertical axis ZZ by the value C (figure 2). A stand 10 of the frame 8 is connected to a movable contact 11 of a circular potentiometer 12 for detecting the direction of slip.

The device works in the following way.

When the pneumatic tire rolls along the tested support surface, in which the device is installed in such a way that its longitudinal axis YY (Fig. 2) coincides with the rolling direction of the pinna, and the ZZ axis is behind the z -z axis, the tire tread comes into contact with the working surface of the sensitive element 4 In the presence of sliding elements of the pneumatic tire tread relative to the supporting platform 2 due to friction forces arising between the sliding tread element and the working surface of the sensitive element 4, the last turn around axis x-x at an angle ct, which is converted by a circular potentiometer 7 into a proportional elec

signal. The angle d is determined by the formula

 21K

where R is the radius of the sphere of the working surface of the sensing element 4 (figure 1); S - Pneumatic tire tread slip.

If the slip direction does not coincide with the tire rolling plane, then the sensing element 4 mounted on the BS 5 in the supports 13 of the frame 8 rotates around the vertical axis z -z by an angle p, which is fixed by a circular potentiometer 12.

The value C (displacement of the z-Z axis relative to the Z-Z axis) is selected from the following considerations. If there are two tire slippage components (along the X-X and Y-Y axis), turning of 35 ° occurs in the XOY plane

25 cop, and

M „where F.

Ptt.x-x With

TR.X-X

With the search for the forces of friction slip in the zone of contact of the tire tread with the surface of the sensing element, acting along the axis X-X;

the distance between the z-z and z-z axes.

To rotate the sensing element 4 around the Z axis, the condition

m „„ in m, + Me ,,

where MC, is the moment of resistance to rotation of the 1U rack;

Mj. - moment of resistance to rotation of the movable contact 11 of a circular potentiometer 12. Obviously,

fp.x-x

Thus, the proposed device, on the one hand, registers the direction of slippage (using a potentiometer 12), and on the other hand, registers the slippage and the nature of slippage (using a potentiometer 7). This makes it possible to measure the pneumatic slip slip path over the bearing surface, and ultimately assess the wear of the pneumatic tire.

Claims (1)

Formula Fig. eteny A device for detecting the slippage of a tread of a pneumatic tire relative to a support surface, comprising a support platform mounted on the housing with a seat in which a sensing element with a spherical working surface is placed for interacting with the tire tread, characterized in that in order to improve measurement accuracy by providing. registration options slippage, it is equipped with a first circular potentiometer for detecting slippage, a second circular potentiometer for detecting the direction of slippage with a frame mounted rotatably in the device housing around a vertical axis offset from the center of the sensing element rigidly fixed on the horizontal axis installed with the possibility rotation in the supports of the frame and connected to the moving contact of the first potentiometer, and the moving contact of the second potential a meter connected to the rack frame. BHHHmf Order 1316/51 Circulation 778 Subscription Branch ShSh Patent, Uzhgorod, ul. Project, 4