Mehrpoliger Motorschutzschalter

摘要

911,580. Protective cut-out arrangements; thermal switches. ELLENBERGER & POENSGEN G.m.b.H. Oct. 4, 1960 [Oct. 24, 1959], No. 34022/60. Class 38 (5). A polyphase motor-protection switch having moving contact springs in each phase normally biased into contact with a respective fixed contact, has a common pivoted control member acted upon by a separate bimetal strip for each phase and a common rockable member having V-shaped recesses in opposite sides thereof by means of which it is suspended between the ends of the moving contact springs and the control member. The fixed contacts 11 are mounted on springs 9 secured by screws 8 to the base 1 and respective terminals 4. Each moving contact 12 is mounted on a spring 13 having a " claw-shaped " end inserted in a slot in a leaf-spring 14 so as to form a pivot. The other end of each spring 13 is formed as a knife edge 15 and engages in a V-shaped recess 16 in the common rockable member 17 which is made of insulating material and has further V-shaped recesses 19 in its opposite side engaged by knife-edge ends 22, 23 of a strips 20, 21 secured by rivets 24, 25, to the common insulating control member 26. The other ends 27, 28 of strips 20, 21 engage loosely in slots in parts 29, 30 secured to the base 1, the slots allowing pivotal movement of the parts 20, 21, 26. Screws 351 and nuts 361 secure the respective springs 14 and bimetal strips 34 together and to the base 1 and the heater windings 35 are connected to their respective bimetal strips at 36 and to terminals 5 at 37. As a bimetal strip 34 is heated its end engages a conical ended screw 38 in the member 26 to rotate it anti-clockwise against the bias of a spring 46 until the knife edges 22, 23 move over centre so that member 17 tilts clockwise and " snaps " the contacts 11, 12 open. As the bimetals cool the switch resets with a temperature differential which can be preset by means of the screws 38 and an adjustable stop screw 49 which engages the member 17. Ribs 41, 411, 4111 on the member 26 and ribs 45 on the member 17, together with corresponding webs 43 and recesses 42 on the base 1 form separate compartments for the phases. One bimetal strip may be omitted and, as shown in Fig. 7, the associated spring 13 may be arranged to control a set of contacts which close when the other contacts 11, 12 open.