Abstract: The horn includes a support casing (1 to 3) in which the peripheries of two facing diaphragms (10, 11) are restrained, a chamber (12) of variable volume being defined between the diaphragms (10, 11) and communicating with a sound-emission duct (50, 51, 70). Respective, opposed ferromagnetic armatures (17, 18) are connected to the diaphragms (10, 11). When a control solenoid (15) is excited by an intermittent current, it causes the armatures (17, 18) to move in opposition and the diaphragms (10, 11), to vibrate in counterphase.

Abstract: An intermittently operating pneumatic vane pump has a cylindrical seat for its rotor constituted by a ring of porous sintered material housed in a container. The lubricating oil is collected in an interspace between the ring and the container when the pump is operating and returns to the pump when the pump is stopped, to keep the ring of the seat impregnated.

Abstract: An electrical compressor for motor vehicle horns, free from water seepage and simple construction wise comprises, all in axial alignment relationship, an electric motor having a stator, a pair of brushes, and a shaft provided with a rotor winding and a commutator, an air compressor having a casing by said shaft, and a bowl-type shell wherein said electric motor and air compressor are mounted coaxially adjacent to the bowl bottom and bowl opening, respectively.

Abstract: An audible warning device which can be fitted indiscriminately to motor vehicles, and is controlled by a push-button switch in a current supply cable or ground conductor of the device, the latter having in both cases similar electrical connections which are few in number. The audible warning device comprises at least one horn which is connected between the current supply cable and the ground conductor and is operated by a control signal, a control unit which is connected to the push-button switch to generate the control signal when the button is pressed, and a voltage regulator which is connected between the current supply cable and the ground conductor and has an output, connected to the control unit, which has a predetermined voltage different from the voltage of the current supply.

Abstract: A signal generator comprising one or two horns and an electrically operated ir compressor is secured to a vehicle body, directly or indirectly, by a screw connection which includes a bolt with a hexagonal head received in a seat on a muff of each horn, the seat being formed by an open-ended channel accommodating the head and an adjacent narrower slot traversed by the shank of the bolt. This bolt may be inserted into a hole in the vehicle body or, in the case of two horns, may engage a strap bolted to that body; alternatively, such a strap with a pair of horns fastened thereto can be bolted to the associated air compressor which for this purpose has two diametrically opposite seats each similar to the one on the horn muff, one of these latter seats serving for the bolting of the compressor to the vehicle body.

Abstract: An electromagnetic sound generator, such as an automobile horn, has a thialled ferromagnetic coil housing with a rim bent back upon itself to form an outwardly projecting peripheral flange embracing a marginal zone of a membrane. A collar formed as an annular extension of that flange, overlying the membrane, engages a thermoplastic ring with freedom of radial expansion of the latter, the ring being cemented or otherwise secured to an overlying resonator with a convoluted shell.

Abstract: A pneumatic sound generator, such as an automobile horn, comprises a genely cup-shaped housing spanned by a membrane that rests against a central tubular boss forming a seat for the mouthpiece of a cornet through which air admitted into the housing via a lateral inlet escapes as the oscillating membrane is lifted off the boss. The cornet abuts an inner annular shoulder of the boss, together with a tubular insert which is either thermoplastic, received between the metallic cornet and housing, or metallic, seated within the mouthpiece of the thermoplastic cornet. In either case, the thermoplastic part--which preferably has a polygonal or corrugated inner cross-section--is tightly squeezed between two metallic members forcing an annular bead thereof into a surrounding groove of the inner periphery of the boss to form therewith an airtight seal.

Abstract: An electromagnetic sound generator, such as an automobile horn, has a thin-walled ferromagnetic housing closed at one end by a membrane which carries an armature extending into an electromagnetic coil mounted in the housing. The rim of the membrane is embraced by a deformable peripheral housing wall bent back upon itself to form an outwardly projecting peripheral flange with a bight portion radially spaced from the membrane, the housing wall extending axially beyond this flange to engage a resonator adjoining the membrane. The armature has an eccentric lug which coacts with a contact spring of an interrupter in series with the coil and which can be limitedly adjusted, by rotation of the armature about its axis, to shift its point of engagement with the contact spring for varying the moment arm of the spring and thus the natural frequency of the sound generator.

Abstract: A vehicular warning device comprises a sound generator of electromagnetic electropneumatic type with two components, one of them including a diaphragm, that are relatively axially movable in a generally cylindrical housing supporting both components. The peripheral housing wall has a corrugated zone forming at least one annular bulge which can be compressed between a pair of clamping jaws during tests following assembly. Such compression, with permanent deformation of the housing wall, reduces the axial height of the housing so as to narrow the air gap between a membrane-supported electromagnetic armature and a confronting core member or to intensify the pressure exerted by the diaphragm upon an entrance end of an air channel normally blocked by that membrane.

Abstract: An electromagnetic sound generator, such as an automobile horn, has a thin-walled ferromagnetic housing closed at one end by a membrane which carries an armature extending into an electromagnetic coil mounted in the housing. The rim of the membrane is embraced by a deformable peripheral housing wall bent back upon itself to form an outwardly projecting peripheral flange with a bight portion radially spaced from the membrane, the housing wall extending axially beyond this flange to engage a resonator adjoining the membrane. The armature has an eccentric lug which coacts with a contact spring of an interrupter in series with the coil and which can be limitedly adjusted, by rotation of the armature about its axis, to shift its point of engagement with the contact spring for varying the moment arm of the spring and thus the natural frequency of the sound generator.

Abstract: An electromagnetic relay comprises a base formed with a depression in which plate-shaped ferromagnetic armature rests under its own weight in an inclined position with reference to the lower surfaces of the legs of an electromagnetic yoke overlying that depression, these surfaces defining with the armature a pair of air gaps which in the unexcited condition of the relay increase in width from one edge of the armature to the opposite edge. A movable contact member in the form of a flat spring bracketed by the yoke legs, spacedly overlying the armature in this unexcited condition, is clamped to the base at the narrow gap end and has a free extremity, coacting with a fixed contact member, at the wider end; magnetization of the yoke elevates the armature into engagement with the contact spring near its clamped extremity and then causes it to swing into contact with the free spring extremity for closing (or opening) a load circuit which is independent of the energizing circuit of the relay.

Abstract: A two-tone signal generator, serving as a horn for automotive vehicles, crises two complementary half-shells whose interior is divided by a common partition into two convoluted wind channels of different length resonating at different frequencies and opening into a common outlet. The inlet to the wind channels comprises a central duct with two lateral branches terminating at a pair of nipples to which a hose from an air blower can be selectively fitted; the junction of the branches with the central duct is an enlarged space containing a freely movable rubber ball which automatically blocks one nipple when air is admitted through the other nipple. The duct communicates with the two wind channels via respective lateral chambers formed in the two half-shells, each chamber being partly closed toward the outside by a lid provided with an eccentric air slot.