Friction material testing apparatus

Apparatus for testing the frictional behaviour of dry friction material in a friction couple with a relatively moving rubbing surface against which it is pressed repeatedly, comprising:

• (i) an element carrier arranged to support a rubbing element of thermally conducted material, having a said rubbing surface, said element carrier being movable in the plane of the rubbing surface,
• (ii) a sample carrier for at least one sample of said friction material, disposed facing said element carrier, one of said element and sample carriers comprising a table that is rotatable within limits of constraint and the other one of said carriers being rotatable with respect to the table,
• (iii) carrier drive means arranged to move said other one of the carriers and the friction couple component thereon orthogonal and parallel with respect to said table and the friction couple component thereon to make and break rubbing contact between the rubbing surface and each contacting sample,
• (iv) measuring means operable to sense the temperature of the rubbing element and, in response to friction between the rubbing surface and friction material, to limit rotation of the table and measure the force applied to said table by way of the rubbing element.
• (v) control means operable to control the carrier drive means to effect frictional coupling in response to the temperature of the rubbing element being below a predetermined trigger temperature, and
• (vi) cooling means operable to extract heat forcibly from the rubbing element to reduce it to said predetermined trigger temperature.