Under Tension: PMI120-F90 Inductive Proximity Sensor
Monitors the correct mounting of motor chain tensioners
Motor control chains often serve as a link between the crankshaft and the camshaft of a drive. Motor chains that are tightened regularly work flawlessly up to a maximum abrasion elongation of two percent. If the motor chain is not tightened, the return strand starts to sag and the chain takes on an unsteady run that promotes abrasion. Damage to the motor will occur if the chain lacks the correct degree of tension.
Motor chains with a minimum wear can greatly extend motor life-span. The company iwis, a chain manufacturer in Munich, Germany produces high-precision chains and is a supplier to many automotive manufacturers.
Fig. 1: Assembly line for motor chain tensioners
During production the assembly is closely monitored and controlled. The Pepperl+Fuchs actuator is mounted to a special control unit (see figure 2). This control unit uses a defined pressure to identify the spring tension of the tappet of the motor chain tensioner. Under this pressure the tappet sinks into the housing. The offset is measured using a PMI120-F90-IE8-V15 inductive proximity sensor on the control unit.
Fig. 2: Unit for controlling the spring tension with PMI120-F90-IE8-V15 inductive path measurement system and BT-F90-W actuator