| 摘要 |
A thermal relay for connection in series with the start winding of an electric motor to permit a high starting current consists of a PTC resistor 2 held in a housing part 1 between resilient contacts 4, 5 having a high thermal resistance to restrict heat transfer to the housing. To this end the contacts are of stainless steel, coated with silver at the ends of the arms 46, 51 which engage the resistor metallisation 8, 9, and the arms are slotted between stiffening ribs. Loss of heat is further restricted by making the housing, consisting of part 1 and a snap-on lid, generally ball-shaped and providing it with internal ribs to space it from the resistor. Integral extensions of the contacts fit onto pins 51.1 of a conventional connector 51. A method of assembling the relay on a production-line is described. <IMAGE> |
