Abstract: An electromagnetic horn has a diaphragm, tone disc, spacer and mass which are clamped together between an abutment shoulder and an annular rib on an internally screw-threaded sleeve, the annular rib being produced by deformation of the sleeve after the aforesaid parts have been mounted on the latter. A screw-threaded rod extending from the armature is engaged in the sleeve. Tuning of the horn can be effected by rotation of the rod without the need either to release and then retighten any locknuts or to deform the body. For ease of assembly of a contact breaker assembly into the horn body, a first arm carrying a first contact is mounted at one of its ends in the body. A second arm carrying a second contact is mounted on the first arm but is electrically insulated therefrom. The second arm has an extension abutting a contact stud fixed in the body. An adjuster is engaged with the other end of the first arm. The second arm can be assembled on the first arm before securing of the assembly in the body.

Abstract: An electrical horn has a hollow body fitted with a diaphragm secured to an armature. A self-supporting coil is disposed with clearance in a recess in the body. The coil has no central former but is provided with upper and lower electrically insulating flanges. The flange has laterally projecting support portions engaging the body. The support portion has an integral upstanding post fitted with an electrically conducting sleeve. Mounted in stacked relationship on the support portion and around the post and sleeve are an eyelet and an electrical connector. The post and sleeve are deformed to produce a head which holds the eyelet and electrical connector in engagement without the need to use a rivet extending through the support portion and the body. This reduces the risk of entry of water into the body in service. The lack of a central former for the coil improves air circulation therearound.

Abstract: A horn flare has first and second plastics mouldings which are welded or adhesively secured together. The first moulding has an end wall having a central opening aligned with the space inside a first annular wall extending integrally from the end wall. A further integral annular wall surrounds the first annular wall and a collar having a stepped annular recess therein surrounds an additional wall. The second moulding has an end wall which overlies the first annular wall and the further integral annular wall. Extending integrally from the end wall of the second moulding are said additional wall and a further wall. The additional wall lies between the first annular wall and the further integral annular wall while the further wall of the second moulding lies outside said further integral annular wall of the first moulding. The second moulding further includes an open-ended flared sleeve which is integrally connected with the further wall of the second moulding by spaced lugs.