Abstract: A flexible capacitor is used in a switch circuit arrangement for activating a vehicle horn. The switch circuit arrangement includes an astable circuit having a flexible capacitor. The astable circuit generates a signal having a frequency that varies in response to force applied to the capacitor. A programmed frequency sensor activates a horn activation signal if the frequency of the signal falls below a programmed threshold.

Abstract: A rear mounted vehicular horn is provided including a vehicle with a front extent and a rear extent. A horn is situated at the rear extent and directed rearwardly from the vehicle. The horn has a speaker for emitting a high intensity tone upon the actuation thereof. Next provided is a pair of horn switches situated within a steering wheel of the vehicle and connected to the horn. The horn switch functions to actuate the speaker of the horn upon the depression thereof thereby emitting the high intensity tone from the rear extent of the vehicle.

Abstract: Disclosed is a diaphragm buzzer including a lower cover and an upper cover. A sheet buzz element having a centered diaphragm is disposed inside the lower and the upper cover and is protectively sandwiched between a press plate and a plastic washer before it is fixed to the upper cover, lest the sheet buzz element should detach from the wires connecting it to a circuit board and become loose and damaged in the two covers.

Abstract: A high output horn for sports' fans can have a pair of plastic tubes spanned at one end by a membrane with a setback of the outer tube from the inner tube of 0.1 to 0.3 mm and a ratio of the inner diameters of the two tubes between 1.1 and 1.7 and a ratio of the outer diameter of the thickness of the membrane spanning the tubes of substantially 1000 to 2000. Air is blown in through a lateral opening in the outer tube and the end opposite the membrane of the air gap between the two tubes is closed.

Abstract: A method for setting the air gap in an automotive horn having an armature and a stud comprises the steps of positioning the stud through an orifice so that it contacts the armature, backing the stud away from the armature a predetermined distance, and fixing the stud to the horn housing so as to establish the air gap between the armature and the stud.

Abstract: An electromagnetic signal horn of a type including a housing, a membrane whose peripheral edge is attached to the housing and which with the housing defines a chamber, an electromagnetic motor arranged in the chamber, and a magnetic core arranged in the chamber with an attaching pin thereof extending through a central opening of the membrane, with a coupling channel thereof, for coupling the chamber with outside atmosphere, being partially defined by a radial recess at the central opening of the membrane, wherein the central opening is four-sided, or square, for simplifying and economizing its fabrication, with a spacing between opposite sides of the central opening being the same, or only slightly larger than, a diameter of the attaching pin.

Abstract: A horn for producing sound at a sporting event or festival has a sound tube coaxially surrounded by a pressure tube with a minimum clearance of 0.2 mm therebetween, a membrane being stretched over the ends of the two tubes and held by a retaining ring under tension. The tubes are held together at the opposite ends by a closing collar which closes the annular clearance and a hole is provided in the pressure tube substantially midway between its ends.

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: A vehicle horn is disclosed with an electronic switching circuit which operates at a switching frequency equal to the resonant frequency of the horn. A sweep frequency oscillator generates a switching pulse train. A transducer and signal conditioner produces a horn output pulse train at a frequency equal to the acoustic output of the horn. The horn output pulse train is applied to one input of a phase comparator. The output of the sweep frequency oscillator is applied to the other input of the phase comparator. The phase comparator generates a stop signal for the sweep frequency oscillator when the input signals are in phase with each other which signifies that the horn is operating at its resonant frequency.

Abstract: A drainage structure of a volute horn including a resonating device has a cover and a base which form a volute sound path. A relatively long and narrow drainage passageway is formed in the portion of the resonating device where water collects for draining water from the sound path such that the sound pressure in the sound path remains constant. As a result, the integrity of the horn sound is maintained.

Abstract: A loud horn for motor vehicles which comprises a hollow housing sealed off by a diaphragm and bearing a vibration electromagnetic generator inside the housing with a coil frame in which the housing is provided with a hole connecting the inside of the housing with the outside allowing for respiration of the loud horn. In order to communicate with said hole, the frame has at least one smaller diameter pipe in order to allow air to penetrate inside the housing, the pipe being provided with a filter preventing water from penetrating inside the loud horn.

Abstract: Adjustment of the pulse energizing frequency and duty cycle of a vehicle horn is described. The horn is blown by a test energizing circuit with a varying pulse frequency and the and the frequency at which the horn produces the maximum sound pressure level is taken as the predetermined resonant frequency. Then the horn is blown by the test energizing circuit at the resonant frequency with a varying duty cycle value of duty cycle which produces a predetermined striking force of the plunger against the pole piece is taken as the predetermined impact-producing duty cycle which is used for setting the operating duty cycle of the horn in a manner depending upon the type of the horn. The horn is then blown by its own electronic energizing circuit and the actual pulse frequency thereof is adjusted, preferably by laser trimming of a resistor, to match the resonant frequency.

Abstract: A volute horn is assembled by integrally attaching a horn body to a resonating device forming a volute sound path. The horn body includes a vibration generating unit for vibrating diaphragm to create a sound, and a cover facing the outer surface of the diaphragm provided so as to block an opening in a housing. The resonating device is formed of a frame and a base. The frame is formed so that the bottom of the sound path is open, and the base is integrally secured to the bottom of the frame so as to block the sound path in an airtight manner. A first opening is formed in the cover, and a second opening is formed in the base. Sound produced by vibrating the diaphragm is transmitted through the first and second openings and into the volute sound path. The first opening communicates with the second opening in an airtight manner.

Abstract: A transducer and tone generator embodying the same and method of assembling the transducer components with the use of an assembly fixture. The transducer components include a rigid annular structure, a pole piece, an electromagnetic coil assembly, and a diaphragm.

Abstract: A vehicle horn has a shield which covers the mouth of the horn's bell to prevent debris from entering the bell. A front sound opening beyond the bell mouth perimeter allows sound to project forwards while still protecting the bell and a rear sound opening aligned with the front sound opening allows debris to pass through both openings without collecting within the space between the bell mouth and the shield. A side surface shields that space and includes a bottom cutout which allows any debris collected to fall out of the space. A vehicle horn has a bell constructed of two tubular sections, the end of each section having a mating flange which fits into a specially adapted clamp. As the clamp is tightened, the tube sections are drawn together until they butt against each other. The clamp is tightened by securing mating collar portions against each other. A pedestal and a rear mounting base are used to connect the horn to a vehicle. The rear mounting base and a mounting bolt are connected to the vehicle.

Abstract: A vehicle air horn is disclosed which is provided with heating cartridges and a temperature sensing switch. The temperature sensing switch automatically turns the heating cartridges on and off at predetermined temperatures. This automatic heating facility enables the horn to remain operational at low temperatures in inclement weather when other unheated horns would be expected to fail.

Abstract: A horn for connection to a pressurized fluid container for sounding multiple tones has a horn body defining a sound chamber and at least one tone altering aperture extending through the horn body into the sound chamber, a sound producing mechanism located within the horn body adjacent the sound chamber, and a trigger assembly for actuating the pressurized fluid container for release of pressurized fluid to flow through the sound producing mechanism into the sound chamber to produce a sound. The horn, when the trigger mechanism is actuated, produces sound having a first tone when the tone altering aperture is unobstructed and a second tone when the aperture is obstructed.

Abstract: According to the invention, a high-powered community alerting and warning device comprising a number of electromagnetic drivers is energized for tone generation by means of a rotary alternator that produces, when driven at a predetermined rotational speed, a sine-wave a.c. in the 400-800 Hz range. The alternator output is applied directly to the drivers, eliminating costly amplifier modules and energizing the drivers for better efficiency and reliability than an amplifier system. The alternator can be the output of a rotary frequency converter, or it can be driven by an engine or a separate electric motor.

Abstract: An armored self-contained outdoor/indoor siren assembly which eliminates the need for an additional protective box and an additional tamper switch which are generally used in the prior art installations. The armored siren assembly of the invention consists of a rigid and strong cover member which forms a housing, and a number of horns mounted within the housing in coaxial nested relationshp with one another which not only form a sound chamber for the siren, but also form a protective means for the sound generating unit of the siren to prevent access to the sound generating unit by unauthorized persons. The cover of the assembly, as well as the various horns included in the housing, and the mounting brackets for the horns, may all be formed, for example, of rustproof diecast aluminum.

Abstract: A pneumatic horn comprises a housing portion, a base portion connected with the latter, a sound horn, which is held in an opening of the housing portion, and a diaphragm which is fixed between the housing portion and the base portion and rests against an inner pipe connection piece. The housing portion and the base portion each comprise a ring. Each ring is connected with a sheet metal jacket or a sheet metal base, respectively, so as to be fixed against rotation relative to it. The housing portion and the base portion carry diaphragm holding surfaces which securely grip the diaphragm all around in a uniform manner when the housing and base portions are screwed together.

Abstract: A tone generator of the type in which a housing defines a pair of communicating chambers one of which is closed except for an area of communication with the other chamber. A thin flat diaphragm of circular configuration is mounted in an operative position over the area of communication between the chambers in engagement with a flat annular surface defining the same. An annular diaphragm retaining member is mounted in an operative position in superposed relation to the diaphragm in fixedly secured relation within the housing. An improved mounting for the diaphragm is provided which includes a plurality of annularly spaced transversely extending diaphragm engaging lugs formed on the retaining member. The lugs extend in engagement with the diaphragm so that when the retaining member is in its operative position the engagement of the lugs with the diaphragm serves to retain the diaphragm in its operative position.

Abstract: The motor chamber of an automotive vehicle horn is vented to the atmosphere through a hole in the diaphragm. The hole is located on a vibratory portion of the diaphragm and is laser drilled to obtain an accurately dimensioned hole with smooth edges.

Abstract: An electric horn, especially adapted for automotive vehicles includes a pole piece and adjusting cap for the driving motor. The pole piece and adjusting cap include a cylindrical shank and an enlarged head including a conical flange. The flange terminates in an annular rim which is in contact with and secured to the horn housing by resistance welding. A magnetic circuit for the motor extends from the pole face of the pole piece and adjusting cap through the shank and the head to the housing and the cross-sectional area for the flux path through the head is at least as great as that in the shank and sufficiently large to avoid undue magnetic saturation. The rim of the enlarged head has a diameter greater than that of the shank and less than the diameter of the housing coil cup to thereby obtain increased stiffness in the connection of the pole piece and adjusting cap with the housing.

Abstract: A sound generating apparatus using piezoelectric elements includes first and second sounding plates arrayed in parallel with each other. The first and second sounding plates respectively include first and second diaphragms, and first and second thin plate-like piezoelectric elements laminated onto the first and second diaphragms. The first and second sounding plates are coupled together at the outer peripheral portions by a ring, thereby forming a hermetically sealed internal air chamber. The first and second sounding plates coupled together by the ring, and containing the internal air chamber cooperate to form a sounding member. The sounding member is supported by means of four resilient supporting members made of, for example, rubber, in a housing. In the housing, a front air layer and a rear air layer are formed on both sides of the sounding member, respectively. The front and rear air layers communicate with each other through a ringlike sound path.

Abstract: An alarm horn includes a one-piece molded body which includes a casing portion having opposite open ends, and a first horn disposed in the casing portion and having opposite open ends. The first horn is connected to the casing portion at their one ends. A second horn of a generally cup-shape is disposed in the first horn in spaced relation thereto. Connective portions extend between the first and second horns to connect them together. A sound-generating unit is disposed in the casing and is fixedly connected to the other end of the first horn.

Abstract: An electric diaphragm horn includes a housing having a diaphragm mounted thereon defining a chamber, the chamber being vented to the atmosphere through the diaphragm.

Abstract: The invention pertains to electric horns for automobiles wherein a metal horn motor housing is assembled to a sound projector formed of synthetic plastic. A metal insert is molded into the projector having a metal flange extending from the projector adjacent a projector mounting surface whereby the insert flange is deformed upon the motor housing to produce an effective mechanical interconnection and assembly of the motor housing and projector.

Abstract: A miniature sounder having a diaphragm closing one end of a tuned chamber. The other end of the chamber communicates with the interior of a tuned housing. The chamber and housing are both tuned to the desired oscillating frequency of the diaphragm with the chamber resonant frequency comprising substantially three times the desired frequency and twice the housing resonant frequency.

Abstract: The invention pertains to an electric diaphragm horn and the method of air gap adjustment wherein the horn utilizes an electric coil mounted with a housing which includes a pole piece; a diaphragm being mounted upon the housing including a plunger to be spaced from the pole piece at a predetermined dimension to produce the desired sound output level. The housing bottom wall is deformed to an extent determined by measurements relative to the housing diaphragm mounting surface whereby assembly of the diaphragm to the housing produces a uniform gap between the pole piece and plunger resulting in a consistency of assembled dimensions. Further, the invention includes an electric horn construction utilizing a diaphragm wherein the motor chamber is vented to the atmosphere through a projector mounted upon the horn housing.

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 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.

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: A horn loudspeaker construction wherein an integrated sound chamber and horn assembly is provided by two uniquely configured members that form a highly efficient horn loudspeaker capable of being utilized within a four-inch type electrical box. The horn loudspeaker includes a sound chamber for receiving a magnetic loudspeaker driving assembly and diaphragm. The sound chamber also includes a sound opening having a predetermined acoustic orientation. A first horn stage has a first opening acoustically coupled to the sound opening and is characterized by a flare rate that expands as the first horn stage extends away from the sound opening. The first stage includes an acoustical orientation at the output end that is at least 90.degree. disposed from the acoustical orientation of the sound opening.

Abstract: Vibrating membrane horn of the type wherein a membrane is applied on a peripheral flange on a case in such a way as to close said case. Said case contains a vibrations generator acting on said membrane and a gasket is interposed between said membrane and said flange. Said gasket consists of an absorbent material impregnated with a water-proofing product.