GB1286177A - Fastener - Google Patents

Abstract

1286177 Electrically operated fastening ELLENBERGER & POENSGEN GmbH 21 Oct 1970 [27 Oct 1969] 50054/70 Heading E2A An electrically operated fastening has a sliding bolt 2, a pivoted lever 7 and has a bimetallic strip 13 which is attached to the lever 7 adjacent a pivoted end thereof and which is also attached to a housing 1. The bending of the strip 13 causes rotary movement of the lever 7 and thus sliding movement of the bolt 2. The bolt is provided with a projection 3 and a flat portion 5 having pins 6 projecting from each side thereof. The lever comprises two insulating plates 8 which are spaced apart by means of a 'U'-shaped member 9 attached thereto, is pivoted to the housing 1 by means of pins 12, and is connected to the bolt 2 by means of an end thereof being located between the pins 6. The bimetallic strip 13 is connected to the member 9 of the lever and has a stud 24 thereof retained against a projection 43 of the housing 1 by means of a member 44. Heating coils 14, 15 are wound on insulating sleeves 22, 23 respectively and the latter are mounted on the strip 13. One end 18 of the coil 14 is connected to a lug 20 and one end 19 of the coil 15 is connected to a lug 21. Ends 16, 17 respectively of the coils 14, 15 are connected to the strip 13. A contact spring 25 is fastened by the rivet 24 to the strip 13 and carries a contact 26 which is engageable with a contact 27 carried by an extension 28 of the lug 21. The fastening is also provided with a lug 31 which is connected to one end of a spring 33 and with a lug 32 having a contact 35 which is engageable with a contact 34 carried by the spring 33. The other end 36 of the latter engages a projection 37 on one of the insulating plates 8. A spring 38 has one end thereof secured, by means of a plate 10, to the lever 7 and has the other end thereof fastened to a lever 39, the latter being carried by the housing 1 and adjusted by means of a screw 41. Electricity supplied to the lugs 20, 21, when a door of a washing machine is closed for example, passes through the coil 14, via the contacts 26, 27 which are closed as shown in Fig. 1. The strip 13 is heated and bends to the position shown in Fig. 2 where the lever 7 has been pivoted to move the bolt 2, against the urging of the spring 38, to its fastening position. The contacts 26, 27 are disconnected due to the pivoting of the lever 7, this allowing electricity to pass through both the coil 14 and the coil 15 but at a reduced rate. Thus the strip is retained in its bent state without being overheated. At the same time the contacts 34, 35 are engaged to connect electricity to a motor, for example, via the lugs 31, 32. When the electricity supply is disconnected from the lugs 20, 21, the strip 13 unbends and the bolt returns to its unfastened position.