Abstract: An apparatus for monitoring a condition of a polishing plate, in particular for detecting the time for the polishing plate to be reconditioned or replaced, comprising a measuring unit containing at least one sensing unit and a signal-conditioning unit; and a data processing unit. The measuring unit is being in contact with the polishing plate and having a possibility to move relative to it. The sensing unit comprises a probing tip and a set of sensors attached to the back surface of the probing tip, and contains at least one sensor of the group of coefficient of friction sensor, acoustic emission sensor, wear sensor. All sensors work simultaneously and their measurement data is processed and analyzed by a data processing unit for obtaining accurate and reliable results.

Abstract: A universal friction tester for testing tribological properties of materials comprises a frame with a carriage sliding in vertical guides and supporting a slide moveable in a horizontal direction. The slide supports a stationary upper specimen, which engages a moveable lower specimen, located in a replaceable module attachable to a base plate of the frame. The modules may be of a rotary, reciprocating, a block-on-ring, or any other type, required for different test conditions. Testing can also be carried out with heating or with the supply of oil in the zone of contact between the specimens.

Abstract: The device of the invention is intended for measuring a loading force and a friction force in a tribological tester. The device consists of two deformation-sensitive sensors for simultaneous equal deformation in two opposite directions for eliminating misbalance created in the measurement system when a single sensor is used. Each sensor is a deformable beam having through longitudinal slots extending in different and non-parallel directions and overlapped within the body of the beam. The sensor deforms in one direction under the effect of a loading force measured by two pairs of strain gauges located on opposite sides of the beam near one end of the beam and in another direction under the effect of a friction force measured by another two pairs of strain gauges located on opposite sides of the beam near the other end of the beam.

Abstract: The sensor of the invention comprises a flexible beam of a rectangular cross section with rigid solid end blocks at both ends for securing the sensor in a tester. The beam has two symmetrically-shaped through slots cut in mutually perpendicular directiors so that they are partially intersect within a body of the beam. Each slot has at its opposite ends notches which are wider than the slots so that the distance from the inner wall of the notch to the outer side surface of the beam is shorter than the distance to this surface from the inner wall of the slot. Strain gauges are attached to mutually perpendicular surfaces at the ends of the beam which are flexible in the direction of the force being measured and are rigid in the perpendicular direction. Under effect of the loading force and of the friction force, the flexible beam acts as a pair of overlapped and mutually perpendicular parallelograms.

Abstract: A tester of the invention has a horizontal base with a vertical column that supports vertical guides for guiding a carriage that supports a rotary drive mechanism for an upper specimen which is secured in a chuck and engages a lower specimen supported by an interchangeable bowl. The tester is also provided with a computerized measuring system for precisely measuring characteristics to be tested. The main distinguishing feature of the tester of the invention is a that a flexible coupling that may have at least one degree of freedom (preferably three) is installed in a link between a rotary motion unit and the chuck for fixing the upper specimen. In other words, the upper specimen is fixed in a self-aligning manner so that its flat working surface is always maintained in full surface-to-surface contact with the lower specimen.