US1161752A - Electric switch. - Google Patents

Description

G. B. THOMAS.

ELECTRIC SWITCH.

APPLICATION FILED APR.8,1914.

Patented Nov. 23, 1915.

lvwe/ntoz G O Pee B. THO/was rmirnn STATES PATENT OFFICE.

GEORGE B. THOMAS, 015 BRIDGEPORT, CONNECTICUT, ASSIGNOR TO THE PERKINS ELECTRIC SWITCH MANUFACTURING COMPANY, OF BRIDGEPORT, CONNECTICITT,

A CORPORATION OF CONNECTICUT.

ELECTRIC SWITCH.

Application filed April 8, 1914. Serial No. 830,492.

T 0 all whom it may concern:

' Be it known that LGEORGE B. THOMAS, a

citizen of the United States of America, and residing at Bridgeport, 1n the county of F airfield and State of Connecticut, have invented a certain new and useful Improvement in Electric Switches, of which the followingis a specification.

My invention relates to electric switches and particularly to snap swltches, and the object of my invention is to provide a switch which may be used to advantage as a starti'ng switch for motors, especially where 1t is desirable to introduce the current gradually which my invention is embodied in one form; Fig. 2 is a detached perspective of the switch spindle elements; Fig. 3 is a plan of the switch cover; Fig. 4 is a similar view of the indicating dial; Figs. 5 to 8 are diagrammatic plans showing the positions of the switch blades-in off, 1?? 2 and on positions respectively; and Fig. 9 is a diagram of the connections from the line wires 1 through the switch to the load.

The switch here shown comprises a base 10 of porcelain or other su table insulating material provlded wlth four comblned wire and switch terminals 11, 12, '13 and 14; Twoof the switch terminals 11 and 12 are arranged ,at Ohelevel-to cooperate with the switch blade 15. The other pair 13 and 14 (not'shown in Fig. l) are arranged at a higher levelin the wellunderstood manner employed in double pole switches, to cooperate with' the upper switch blade 16. This upper blade 16 is carried .by a yoke 17 rigid with the switch spindle 18 and here shown soldered thereto at 19', togetherwith the crown 20. Thedownwardly extended fingers of the latter serve as abutments for the upper end of the coil spring 21 whichsurrounds the spindle andjengages at its lower end one of the rivets 22 which connect switch blade 15 to the yoke 23. A pair of lugs 21 (only one of which is shown) on the yoke straddle, in well understood manner,

the arm 25 of the stop plate 26 whichis cen-,

trally apertured to-aflord' a bearing for the cam 27 clamped in the notch 28 of the spindle. The downwardly angled finger 29 on' arm 25 engages the several shoulders'of the.

ratchet plate 30 pinned to the-plate 311 which is set into thebase 10 and held against rotation in any suitable manner; A washer 32 engaging the notch 33 in the, lower end of the spindle below the web 3st of the base, holds the spindle and parts assembled against withdrawal.

The ratchet plate 30 is of peculiar form, having not only the four usual shoulders a, b, c-and (Z arranged at angles of 90 apart, but also additicnal shoulders e and 7 diametrically opposite each other and spaced equidistant between shoulders a and b on the one side and shoulders c and on the other side. The function of these supplemental stops will be presently pointed out.

The'switch is provided also with a cover 35 having in its upper face two sight apertures 36. and 37 cut at different radial distances from and on opposite sidesof the aXis of the switch. Immediately beneath the cover is a dial 88 rigid with the switch spindle 18 and having on concentric circles indications of the switch position. Thus in the outer circle which registers with aperture 37 viz., 4.1. The other main 10 is connected to two terminals 11 and 11 ofthe switch, while the cooperating switch terminals 12 and 13 are connected to the load wire 12, the lead from 12 being direct, whereas the lead from 13 is through a resistance R.

The operation of the switch is as fol lows :Assuming the blades to be in the-position shown in Fig. 5, the switch is "otf with the switch blade 15 underlying the raised switch terminals 13 and 11. If the switch spindle 18 is now rotated in the usual direction (see arrow Fig. 5). bynneans of the thumb key 13 not only is the switch blade 16 carried around with the spindle into position to engage the terminals 13 and LL but the switch spring 21 is also placed under tension while at the same time the-stop lug 29 is moved outward along the face of shoul- 'der or b of the ratchet plate. When the blade 16 has reached its full contact position (Fig. 6), the numeral 1 on the dial 38 appears below aperture 37 in the cover, the stop finger .29 has escaped the shoulder cl or Z) and impinged upon shoulder e or 7 carrying switch blade to the-position shown in Fig. 6.

]merely to partially relieve the spring 21 of its tension; Consequently if the thumb piece 43 were released, the blade 16 would be rotated backward and the connection between terminals 14: and 13 broken. This up, by rotating the switch spindle in the direction of the arrow until the numeral 4 2 77 appears beneath the aperture 37 in the cover.

This frees the stop 29 from the shoulder e or f and the switch blade 15 is thereupon rotated until stop 29 engages shoulder a or a in which position the blade 15 connects terminals 11 and 12 and the resistance R between the main and the motoris short circuited. When the thumb piece 43 is now released, the tension of the spring 21 is sufficient to force it past its contacts '13 and 14: to the position shown in Fig. 8, thus leaving the connection solely through the blade 15. In this position of rest the word On .'ap-

pears at the aperture 36 in the cover. To return to the off position the spindle is rotated in the usual manner until the finger 29 escapes shoulder a or c of the ratchet plate, whereupon the switch blade 15 is rotated through an angle of 90 to position beneath the terminals 13 and 14, since there are no stop shoulders such ase and f intermediate shoulders a and d on the one hand, or 0 and. Z) on the other hand.- The blade 16 also takes the position shown in Fig. 1 and the word Ofi' appears on the dial beneath the aperture 36 in the cover.

It' will be recognized that while thebase and combined wire and switch terminals have a form commonly found in double .pole switches and a pairof switch blades cooperatingwith' these terminals is provided, yet the device is in reality a combination of two single pole switches each blade acting independently of and alternatively to the other. Again, it will be noted that while the blade 15 carried by the yoke 23 is controlled bythe escapement mechanism and has a snap make and break action (which is important because it governs the full current) yet blade 15, which controls the resistance shunt, has neither snap make nor break, but moves with the switch spindle as hi. the. thumb key is rotated by hand or. in the reverse direction by the spring 21.

Various modifications of he construction This rotation of blade 15 serves limit myself to the details shown.

I claim as my invention 1. In an electric switch, two pairs of switch terminals of like polarity, two double break switch blades coiiperating therewith, and means for establishing connection through the switch, first through one switch plate and then through the other, substantially as described.

2. In an electric switch, two pairs of switch terminals of like polarity, two double-break switch blades cooperating therewith, and means forestablishing connection through the switch, first through one switch plate and then through the other, only one of said switch blades making and breaking contact with the switch terminals with a snap action.

- 3. In an electric switch, independent switch terminals, independent switch blades '-.cooperating therewith, a switch spindle com.-

mon to said switch blades, one of said blades moving with the spindle and the other having an escapement control actuated by said spindle.

4. In an electric switch, an actuating spin dle, a, switch blade moving therewith, an independent switch blade, an j escapement mechanismtherefor and means for actuating said mechanism from the switch spindle.

5. In an electric switch, an actuatingspindle, a switch blade moving therewith, an independent switch blade journaled on said spindle, an escapement mechanism for said blade comprising a spring operatively connected .at one end to the spindle and at its other en to said escapementcontrolled blade, and independent switch terminals for said respective blades, the blade moving with thes'with spindle making contact while the escapement spring is still under tension and in advance of the contact made by the escapement controlled blade, substantially as described.

6. In an electric snap switch, an escapement mechanism comprising a ratchet plate having four stop shoulders spaced 90apart and a pair of diametrally opposite auXiliary stop shoulders arranged midway between opposite pairs of said first mentioned shoulders, for the purpose described.

v7. An electric switch having a switch spindle, two independent single pole double break switch blades thereon, switch terminals therefor, and means for bringing said blades into engagement with the switch terminals serially, substantially as described.

8, An electric switch having a switch spindle, two independent single pole double make switch blades thereon, switch terminals therefor, and means for bringing said blades into engagement with the switch terminals serially, only one of said blades having a snap action, substantially as described.

I 9. In a motor starting switch, switch terminais for shunt resistance connection be- In testimony whereof I have signed my tween main and motor c1rcu1t, and switch name to this specificatlon 1n the presence of 10 terminals for a direct connection between the two subscrlbmg wltnesses.

main and motor circuit independent rotary switch blades cooperating with said termi- GEORGE THOMAS nals, and a snap switch escapement mecha- 'nism controlhng only the make and break of the blade making the direct connection.

' Witnesses:

G. W. Goonmnen, H. M. WISHERT.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0."

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