US2107138A - Electric switch - Google Patents

Description

Feb. 1, 1938. F B1RD 2,107,138

ELECTRIC SWI TCH Filed June' 28, 1937 2 Sheets-Sheet 1 F J Hilllllllll JouRce F Pa WEI? ATTOR N EY Feb. 1, 1938.

L. F. BIRD 2,107,138

ELECTRIC SWITCH Filed June 28, 1937 2 Sheets-Sheet 2 QZINVENT? fid/EC M.

ATTOR N EY 0, applied to the tube. Such means have comprised projecting lug l9, engageable by the cam to move 20 A starting device of this type is disclosed in U. S. I I and resting on the torsion spring I2 is a dial 25 switch embodying my invention, 3| being attached to the terminal 4.

Patented Feb. 1, 1938 2,107,138

UNITED STATES PATENT OFFICE ELECTRIC SWITCH Lester F. Bird, Newark, N. J., assignor to Hanovia Chemical and Manufacturing Company, Newark, N. J a corporation of New Jersey Application June 28, 1931, Serial No. 150,698

Claims. (Cl. 200-4) This invention relates to electric switches and Fig. 5 is a sectional view taken on line 5-5 of more particularly to the provision of means for Fig. l, starting gas or vapor filled electric discharge Fig. 6 is a sectional view taken on line 6-6 of tubes operating on low voltages. Fig. l, I

In the operation of electric discharge tubes on Fig. 7 is a fragmentary perspective view of de- 5 the low voltages such as commonly used for tails of the invention. house lighting purposes, difiiculties in starting Referring to the drawings, it will be seen that are due to static charges which collect on the the switch mechanism is mounted on an insulatwalls of such tubes and prevent the static fields ing base 5 carrying combined wire and switch produced by application of potentials to the terminals 4 and 6, and provided with an encloselectrodes of being effective at the opposite ends ing cover 1. The switch blades 8 are integral of the tube, thus preventing a discharge. If the with a yoke 9 which is fastened to a disc l0, potential at the electrode is increased sufficiently, loosely mounted on a shaft ll, which is encirthese static charges are overcome and a discled by a torsion spring l2. Fixed to shaft H is charge is started. Heretofore, to overcome these a cam l3, bearing against the inner surface of an static charges, there has been provided means annular member l4, which is provided with a for automatically shocking the discharge tube projection l5, engageable with stops i6 on a with a surge of relatively high frequency elecplate I1, fixed in a recess l8 in the base 5, (see tricity at elevated voltages after the power is Figs. 4, 5, 6). The member I4 has an inwardly generally the provision of a capacitor in parallel the projection l5 from engagement with the with the tube, which capacitor is intermittently stops IS, the projection l5 being provided with a connected and disconnected from the electrical lug movable in a guide slot 2| in the disc I0. circuit after the application of power to the tube. Loosely mounted at the upper end of the shaft Patent 2,082,939, issued to Lester F. Bird on June 22 having depending lugs 23 for engaging an end 8, 1937. 35 of the torsion spring 12. Fixed to the upper It is, therefore, an object of this invention to side of the dial 22 is a small bridge 24 to which provide a snap switch for use in a starting deis fixed a small stub shaft 25 having the upper vice for low voltage electric discharge tubes, end thereof screw threaded to receive an interwhich snap switch has means for applying power nally threaded knob 26; the latter being proto the discharge tube and immediately therevided with a recess 36 in which is positioned a after to automatically connect and disconnect a coil spring 31resting upon the casing 1 when the capacitor in a parallel circuit. knob is screwed on to the stub shaft.

A further object is the provision of a snap Fixed to the upper end of the shaft H is a switch in which the simple operation of turning small bar 21 extending transversely of the bridge the switch to the "on position automatically, ap- 24, so that after the dial has made a predeterplies power and after the application of power mined free movement on the shaft II, the bar 21 immediately connects and disconnects a parwill engage the bridge to cause the shaft to allel circuit a plurality of times. move with the dial. The dial has on the pe- These and other advantageous objects, which riphery thereof diagonally arranged sections of will later appear, are accomplished by the simple teeth 28 and recessed portions 29. The teeth and practical construction and arrangement of 28, when the dial is moved to a predetermined parts hereinafter described and exhibited in the position, engage a bent portion 30 of a leaf spring accompanying drawings, forming part hereof, 3| to move the contact 33 at the end of the spring and in which: into engagement with the contact 34 mounted on Fig. 1 is a vertical sectional view of a snap a terminal 32, the other end of the leaf spring Fig. 2 is a sectional view looking upwardly on In operation, when the knob 26 is rotated, the line 22 of Fig. 1, dial 22 rotates freely on the shaft ll until the Fig. 3 is a wiring diagram showing the applibar 21 engages the bridge 24, after which the cation of the switch for starting a vapor electric shaft and dial will rotate together. During the device, free movement of the dial 22, the torsion spring Fig. 4 is a sectional view taken on line 4--4 I2 is wound up due to the fact that the lower of Fig. 1, end of the spring is fastened to the disc ill,

iii!

which is prevented from rotating by the lug 20 in slot 2i, movement of said lug II being prevented by the step ii. Further rotation of the dial 22 causes the bridge 24 to engage the bar 21 and to rotate the shaft H, to also rotate the cam within the annular member l4. As the cam rotates. it bears against the inwardly projecting lug i9 to move the annular member is linearly which causes the projection II to become disengaged from the stop is, thus allowing all of the parts to rotate until the projection it engages the next adjacent stop II. The switch blades have now been brought into contact with the terminals 4 and 6 to apply power, and after the switch blades have been moved to such position and the knob released, the wound up torsion spring I! causes the dial 22 to rotate in the opposite direction, during which the teeth 2| bear against the bent portion Ill of the leaf spring II to make a plurality of successive engagements of the contact members 38 and N.

In Fig. 3 is shown a wiring diagram of a circuit for a vapor electric discharge tube 40, having in parallel therewith a condenser or capacitor M. It will be seen that after power has been applied by means of the terminals 4 and l to the discharge tube, the production of a plurality of uccessive'makes and breaks of the circuit through the condenser by means of the teeth 2| engaging the projection 30, produces the necessary shocking or instantaneous high frequency voltage for starting the tube on a low voltage circuit.

when the knob is again rotated in the same direction, the switch blades are moved to the "off" position, under which circumstances the depressed portion 20 is presented adjacent the bent portion 80 of a spring Ii, and accordingly, no contact is made between the contacts I8 and I4.

From the above description it will be seen that there has been provided a simple and reliable switching device for applying power to an electrical discharge tube for example, and immediately after the application of power to automatically successively make and break a circuit a plurality of times through a capacitor in parallel with the discharge tube.

The foregoing disclosure is to be regarded as descriptive and illustrative only, and not as restrictive or limitative of the invention, of which obviously embodiments may be considered, including many modifications, without departing from the general scope herein indicated and denoted in the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a switch for starting vapor electric discharge devices, a pair of terminals adapted to be connected to a source of power, a base upon which the terminals are mounted. a spindle rotatably mounted in said base, means carried by the spindle for closing a circuit between said terminals, a dial rotatably mounted on the spindle, a torsion spring resisting rotation of said dial, means for producing a lost motion connection between said spindle and dial, a leaf spring attached to one of said terminals, said spring having an inwardly bent portion, said dial having sections of its periphery provided with teeth adapted to enage said bent portion of the leaf spring, and a third terminal mounted upon said base and positioned to intermittently engage said leaf spring :vhen the teeth on the dial engage said bent por- 2. In a switch for starting vapor electric discharge devices, a base, a pair of terminals mounted on said base and adapted to be connected to a source of power. means for closing a circuit between said terminals, a dial, means for rotatably supporting said dial on the base, a torsion spring resisting rotation of said dial, a contact member comprising a strip of resilient material with a bent portion attached to one of said terminals, said dial having sections of its periphery provided with teeth adapted to engage said bent portion of the contact member, and a third terminal mounted on said base and positioned to be intermittently engaged by said contact member when the teeth on the dial engage said bent portion.

3. In a switch for starting vapor electric discharge devices, a base, a pair of terminals mounted on the base and adapted to be connected to a source of power, a dial having sections thereof provided with spaced projections, said dial being rotatably mounted on said base, a torsion spring resisting rotation of said dial, a flat spring member having a bent portion and attached to one of said terminals, the projections on said dial bein adapted to engage said bent portion, a third terminal mounted on said base and adapted to be engaged by said flat spring member when the projections on the dial engage the bent portion. and means to close the circuit between said first pair of terminals, said torsion spring after the closing of said circuit automatically rotating the dial in an opposite direction to cause the projections thereof to intermittently engage the bent portion of said member and thus produce a plurality of closings in rapid succession of a circuit through said third terminal.

4. In a switch for starting vapor electric discharge devices, a base, a pair of terminals mounted on said base and adapted to be connected to a source of power, a leaf spring having a bent portion connected to one of said terminals, 9. third terminal mounted on said base, a dial having sections thereof provided with projections adapted to engage said bent portion to cause said leaf spring to contact the third terminals, means associated with said dial whereby the rotation of the dial will close a circuit between the first pair of terminals, and spring means for reversing the rotation of the dial immediately after the closing of said circuit, to cause the projections on the dial to'engage the bent portion to cause the spring to intermittently engage said third terminal a plurality of times in succession.

5. In a switch for starting vapor electric discharge devices. a base, a pair of terminals mounted on said base adapted to be connected to a source of power. a third terminal mounted on said base, a dial, means associated with the dial so that the rotation of the dial in one direction will close a circuit between said first pair of terminals, spring means resisting rotation of said dial in said direction, and means associated with said dial to open and close a circuit between said third terminal and one of said pair of terminals a plurality of times in succession when the spring means rotate said dial in the reverse direction after the closing of the circuit between said first pair of terminals.

LESTER. 1". BIRD.

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