GB294875A - Improvements in sound reproducers - Google Patents

Abstract

294,875. Brandes, Ltd., (Assignees of Sollie, S. A.). July 30, 1927, [Convention date]. Diaphragms; loud-speakers; magnetic instruments. - In a sound reproducer employing a conical diaphragm which is supported in a plane intermediate the apex and the periphery, the diaphragm is driven by a moving coil and the supporting means are adapted to facilitate assembly with the magnet system. As shown the diaphragm 1 is supported from a ring support 3 in a plane intermediate the apex and the periphery by a flexible membrane 2 which extends over the beaded edge of the ring 3 and is secured by a ring 4. The support 3 is mounted on a plate 5 of magnetic material apertured centrally to receive the coil bobbin 9 which is supported from the diaphragm by a cone-shaped plate 11. Arms 15 mounted on the plate 5 support channel-shaped rings 19, 21 between which is clamped an annulus 24 of flexible material connected to the edge of the diaphragm and adapted to damp the movements of the diaphragm. The damping annulus 24 may be divided into a number of segments. A felt pad 23 mounted in the ring 21 may be pressed against a baffle board or panel. The plate member 5 is clamped by bolts 29, Fig. 5, to a pot magnet 26 having an energizing winding 27 and a central pole 30 adapted to enter the bobbin 9 and having a recess 31 adapted to accommodate the diaphragm. Specification 276,900 is referred to. The Specification as open to inspection under Sect. 91 (3) (a) also states that the space between the membrane 2 and the plate 5 forms a damping chamber for the diaphragm. This subjectmatter does not appear in the Specification as accepted.