Abstract: This invention relates to coil assemblies and in particular, but not exclusively, to such assemblies for acoustic transducers. Thus a transducer 10 includes a case 11 in which is located a coil 16 mounted on a flexi-circuit, which locates the coil 16 for its assembly handling and which allows various configurations within the case 11. A method of winding the coil 16 and mounting it on the carrier 17 is also described.

Abstract: This invention relates to electroacoustic transducers of the type which incorporate a reed armature. Thus a transducer 10 comprises a coil 12, magnets 13,14, pole pieces 15,16 and a reed armature 17, which passes through a central tunnel 18 defined the coil. A central portion 19 of the reed 17 lies within the tunnel and has opposed formation 20,21 which limit the possible deflection of the reed 17. Other deflection limiting arrangements are described.

Abstract: This invention relates to coil assemblies and in particular, but not exclusively, to such assemblies for acoustic transducers. Thus a transducer 10 includes a case 11 in which is located a coil 16 mounted on a flexi-circuit, which locates the coil 16 for its assembly handling and which allows various configurations within the case 11. A method of winding the coil 16 and mounting it on the carrier 17 is also described.

Abstract: This invention relates to electro-acoustic transducers such as is generally indicated at 10 and which comprise a body 11 defining a chamber 12, a plate 13 bearing a micro-phone or speaker 14 to which is attached a stalk 15, a diaphragm 16, connectable to the stalk 15, which extends substantially across the chamber 12, an end piece 17 and an end cap 18. The end piece 17 has a kidney-shaped recess 21 which provides the main communication path between subsidiary inlets/outlets 19 and a main inlet/outlet 20. When the channel 22 is closed off by the end cap 18 it is effectively in the form of a tube and constitutes a Thuras tube. The length of this path effectively creates a long discharge path between the wearers' ear and any grounded metal part within the transducer and hence protects against electric shock.