GB374946A - Improvements in or relating to telephone handsets or microtelephones - Google Patents

Abstract

374,946. Sets. STANDARD TELEPHONES & CABLES, Ltd., GRACE, B. B., and NEILSON, C. B. V., Connaught House, Aldwych, London. March 19, 1931, No. 8448. [Class 40 (iv).] A telephone handset is formed. or moulded from two parts, one of which comprises the portion H of T-cross section and the transmitter and receiver casings T, R whilst the other part consists of a member P, semi-ellipsoidal in form, which forms with the portion H the handle of the handset and acts to close the backs of the transmitter and receiver casings. If desired, the mouthpiece and/or earpiece can be made separate and inserted through the back of the casings before the transmitter and receiver capsules are inserted. The two parts are held together by screws passing through clearance holes in the fin M into projections I on the member P, and the transmitter and receiver capsules are held in place by springs V surrounding projections U on the member P. The capsules are connected by two flexible conductors, Fig. 4, bound together to form a loop W which closely embraces the fin M, whilst the three conductor cord from the transmitter casing passes through an aperture moulded in the edge of the transmitter casing T. The cord hole could be formed by depressions in the edges of both members H, P. According to a modification, a bowspring positioned on the projections I is provided both to keep the capsules in position and to act as the common conductor therefor, this spring, if desired, being formed in two parts joined by a flexible conductor to avoid howling. Additional fins may be provided at each end of the portion H and these may be continued beyond the handle portion partially around the casing portions so as to give additional strength thereto. Alternatively, the fin M may divide into two portions at each end. Various means are described for taking the strain on the cord. As shown, the cord is provided with a metal clip A having a tag B projecting into a slot C in the cord hole, or two oppositely directed tags could be provided to engage slots in the periphery of the cord hole. Alternatively, the cord may be passed around the nearest assembly screw or through a vertical slot in the fin M or one or two pro. jections may be moulded on the casing opposite the cord hole to engage one or two loops in the cord. Further alternative means comprise pegs engaging holes in the two 'parts of the handset and passing across the cord hole or the provision of a strain-cord connected to the inner surface of the handle.