US3618080A

US3618080A - Low-energy input buzzer

Info

Publication number: US3618080A
Application number: US53827A
Authority: US
Inventors: Cleon F Frey
Original assignee: INT FLASHER CORP
Current assignee: INT FLASHER CORP
Priority date: 1970-07-10
Filing date: 1970-07-10
Publication date: 1971-11-02
Anticipated expiration: 1988-11-02

Abstract

A vibratory buzzer device having a relatively thin-gage metal, cup-shaped cover or housing which acts as a sounding surface when struck by a electromagnetically actuated vibrating reed which strikes the cover through a hard, electrically insulating hammer element, the cover thus being electrically insulated from the buzzer circuit.

Description

United States Patent Bayamon, P.R.

Appl. No. Filed Patented Assignee LOW-ENERGY INPUT BUZZER [5 6] References Cited UNITED STATES PATENTS 509,050 11/1893 Schweiger 340/396 3,425,057 H1969 Doggart 340/396 3,540,039 ll/l970 McCarty 340/402 Primary ExaminerThomas B. Habecker Attorney- Woodard, Weikart, Emhardt & Naughton ABSTRACT: A vibratory buzzer device having a relatively thin-gage metal, cup-shaped cover or housing which acts as a sounding surface when struck by a electromagnetically actuated vibrating reed which strikes the cover through a hard, electrically insulating hammer element, the cover thus being electrically insulated from the buzzer circuit.

4 Claims, 4 Drawing Figs.

U.S. Cl 340/396, 340/402 Int. Cl G08b 3/00 Field of Search 340/396, 402, 392

BACKGROUND OF THE INVENTION Audial signalling devices have been utilized in many and various applications. Their use in conjunction with turn signal apparatus, mandatory on motor vehicles, has made important the provision of low-cost, low-energy input vibratory mechanism which will have a long operating life and a relatively high sound output.

The present invention fulfills these requirements by utilizing an electromagnetically actuated, vibrating reed carrying an electrically insulating striker which engages the cup-shaped thin metal housing cover for the apparatus, consequent vibration of the cover itself producing the desired audial signal.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a side sectional view of the apparatus embodying the present invention.

FIG. 2 is a top plan view of the apparatus shown in FIG. I with the cup-shaped cover removed.

FIG. 3 is a top plan view of the vibrating reed component of the apparatus.

FIG. 4 is a schematic illustration of the electrical circuit of the apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, the apparatus includes a circular, rigid baseplate 10, formed of a suitable electrical insulating material. Covering the upper face of the baseplate is a cupshaped cover 11, preferably formed of thin-gauge metal, which is secured or clamped only at its circular margin 12 to the peripheral portion of the baseplate 10. A bifurcated chassis member 13 is formed to provide a central, extending leg 14 and two downwardly flanged mounting legs 16 and 17 which are riveted to the baseplate 10.

The end of the chassis member identified at 17 is upwardly flanged and has secured to it a reed 21, shown in detail in FIG. 3 and formed of a resilient metal. The reed 21 and the portion 17 of the chassis are in electrically conducting relation, being clamped therein by the enclosing clamp portion 22 of the rigid metal arm 23 which carries a stationary electrical contact 24 at its free end. An electrical insulating wrap 26 permits the portion 22 to clamp the reed and chassis without providing electrical continuity to the arm 23 and its contact 24.

Intermediate its ends the reed 21 carries an electrical contact 27 which is adapted to cooperate with the stationary contact 24. At its free end the reed carries an armature weight 28 and, extending upwardly from the weight 28 is an abutment formed by a glass bead 31. The bead 31 functions as a striker engaging the inner face of the concavo-convex depression 32 in the center of the cover 11. The reed 21 is provided with a struck-out portion or notch 21a adjacent its fixed end, the slot serving to facilitate flexibility of the reed permitting it to vibrate at a lower voltage placed on the coil which induces its vibratory motion as will subsequently be described.

The central extending leg 14 of the chassis has mounted thereon an electrical coil 34, the central, terminal portion of the leg 14 acting as the electromagnetic core for the coil and permitting flux linkage of the core and the armature weight 28 when the coil is electrically energized. Extending from the outer face of the baseplate 10, and attached thereto by suitable tabs are electrical terminal members 36 and 37 (FIG. 2). As will be evident from FIG. 2, a wire 35 connects the terminal 36 to the arm 23 and its contact 24. A wire 38 (FIG. 1)

connects one end of the coil 34 to the chassis and a wire 41 connects the other end of the coil to the terminal 37. The electrical circuit thus provided is shown schematically in FIG. 4.

In operation, when the starting voltage is placed across the terminals 36 and 37, energization of coil 34 will serve to deflect the reed 21 downwardly, breaking or separating the contacts 24 and 27. As will be evident from FIG. 4, separating of contacts 24 and 27 breaks the circuit through the coil 34,

deenergizjng it, and releasing the armature 28 and the reed to which it is attached. The consequent rebound movement of the reed upwardly causes the abutment 31 to strike the cover portion 32 and the vibratory repeating of this cycle causes a corresponding vibration of the cover producing a loud, audible signal.

The buzzer apparatus described has a prolonged operating life and a relatively high sound output. The thin, cup-shaped cover is clamped or secured only at its marginal edges leaving the remainder of the cover free to vibrate in accord with the frequency of the blows delivered to it by the abutment 31. The cover itself acts as the sound cone or anvil thus eliminating that component of conventional structures. The thin, slotted reed with the weight 28 at its free end produces the required sound with a minimum expenditure of energy since only the internal friction in the reed must be overcome by the electromagnetic force generated by the coil 34. A relatively small wire coil may thus be used thereby reducing material cost and reducing the heat generated by the structure in operation and thereby permitting the apparatus to be continuously operated. The cover must be electrically dead, that is, electrically insulated from the circuit through the contacts and coil. The glass bead, because it is hard and is electrically insulating, provides the type of striker necessary to achieve these advantages.

1 claim:

1. An electromagnetically actuated, low-energy audio signalling device comprising a rigid baseplate having electrical terminals extending through the plate and from one face thereof, a cup-shaped cover secured only at its margin to said baseplate and overlying the other face of the plate, a flexible reed cantilever mounted within said cover and supported from said baseplate, the free end of said reed carrying weighted striker adapted to strike said cover when the reed is flexed, an electrical contact carried by said reed intermediate its length and adapted to cooperate with an adjacent fixed contact to control an electrical circuit between said electrical terminals, an electromagnetic coil supported from the baseplate adjacent said reed and electrically connected in series with said contacts, the flux linkage of said coil and reed when the coil is energized serving to flex said reed away from said cover and opening said contacts, the rebound of said reed to reclose said contacts then causing the reed to flex toward said cover and said striker to strike said cover, the cyclical flexing of the reed and striking of the cover thereby causing said cover to correspondingly vibrate producing an audial signal.

2. An audio signalling device as claimed in claim 1 in which the portion of said weighted striker which engages said cover is formed by an electrically insulating glass bead.

3. An audio signalling device as claimed in claim 2 in which a central indentation is formed in said cup-shaped cover to define the area of the cover adapted to be engaged on the convex side of the indentation by said glass head portion of said weighted striker.

4. An audio signalling device as claimed in claim 3 in which said flexible reed is slotted intermediate its ends to reduce the force necessary to flex said reed.

Claims

1. An electromagnetically actuated, low-energy audio signalling device comprising a rigid baseplate having electrical terminals extending through the plate and from one face thereof, a cupshaped cover secured only at its margin to said baseplate and overlying the other face of the plate, a flexible reed cantilever mounted within said cover and supported from said baseplate, the free end of said reed carrying weighted striker adapted to strike said cover when the reed is flexed, an electrical contact carried by said reed intermediate its length and adapted to cooperate with an adjacent fixed contact to control an electrical circuit between said electrical terminals, an electromagnetic coil supported from the baseplate adjacent said reed and electrically connected in series with said contacts, the flux linkage of said coil and reed when the coil is energized serving to flex said reed away from said cover and opening said contacts, the rebound of said reed to reclose said contacts then causing the reed to flex toward said cover and said striker to strike said cover, the cyclical flexing of the reed and striking of the cover thereby causing said cover to correspondingly vibrate producing an audial signal.

3. An audio signalling device as claimed in claim 2 in which a central indentation is formed in said cup-shaped cover to define the area of the cover adapted to be engaged on the convex side of the indentation by said glass bead portion of said weighted striker.