Overview
Projects
Specifications
nCATS has a multi-stationed wear rig (TE85), designed and manufactured, manufactured by Phoenix Tribology Ltd. The configuration is an eight station orbital tooth brushing rig provides circular orbital, elliptical orbital and reciprocating motion, with fixed tooth brush samples loaded against moving teeth samples.
Toothbrushes are cut down for easy attachment to the loading arms. The arms are provided with adjustable counter weights allowing neutral balancing to be achieved. Spirit levels are provided on each arm to aid with levelling. Teeth samples, which are normally set in epoxy discs, are held in radially sprung fixtures. These are then mounted in individual baths on the motion plate. Load is applied directly to each toothbrush sample by dead-weights acting on linear bearing mounted load rods.
The motion system comprises a platform mounted on an x-y slide assembly and actuated by a double scotch yoke mechanism driven by an a.c. gear-motor. The frequency of motion is controlled by inverter and may be adjusted in the range 0.2 to 2.0 Hz. The displacement on one axis is set at an amplitude of 5 mm (stroke of 10 mm) and the amplitude on the orthogonal axis may be set at 0 mm (reciprocating), 1, 2, 3, 4 mm (elliptical orbital motion) or 5 mm (circular orbital motion).
Eight computer controlled peristaltic pumps deliver toothpaste and saliva simulant to the brushing surface. This allows independent ‘slurry’ delivery.
The rig has three axis force transducers may be incorporated on as many stations as is required to provide measurement of applied load and frictional resistance on orthogonal axes. A high speed data acquisition interface is included for recording the signals.
The current project is exploring the polishing effects of different abrasive particles typically incorporated in toothpaste.
- The effect of shape and size distribution of abrasive particles on the volume loss of enamel using micro-abrasion
- Evolution of wear on enamel caused by tooth brushing with abrasive toothpaste slurries
Specifications:
| Attribute | Range/Value |
|---|---|
| Load per brush: | 150 to 500 grams |
| Motion x direction: | 10 mm (fixed) (+/-5 mm) |
| Motion y direction: | 0 to 10 mm in 2 mm steps (+/-0, 1, 2, 3, 4, 5 mm) |
| Maximum Frequency: | 2 Hz (120 rpm) |
| Automatically Controlled Parameters: | Frequency Test Duration Fluid Flow Rate |
| Manually Controlled Parameters: | Load Y Amplitude |
| Measured Parameters | Frequency Load (optional) Friction Force (optional) Number of Cycles |
| Services - electricity | 220/240V, single phase, 50 Hz, 3 kW |