US1519924A - Electric switch - Google Patents

Description

. JNVENTOR I71? v10 H- NERO A. H. NERO ELECTRIC SWITCH Filed Nov. '7, 1922 III" Patented Dec. 16, 1924.

UNITED STATES PATENT OFFICE.

ARVID H. NERO, NEW BRITAIN, CONNECTICUT, ASSIGNOR TO THE ARROW ELECTRIC COMPANY, OF HARTFORD,

NEGHCUT.

CONNECTICUT, A COItLPORATION- OF CON- ELECTRIC SWITCH.

Application filed November To all whom it may concern:

Be it known that I, Anvn) H. Nnao, a citizen of the United States of America, residing at New Britain, in the county of a Hartford and State of Connecticut, have invented certain new and useful Improvements in Electric Switches, of which the following is a specification.

My invention relates to electric switches,

1 and particularly to switches of the toggle mechanism type. The object of my invention is to provide a simple and efic ent means for posit1vely insuring the operation of the toggle n the accompanying drawings I Fig. 1 is a longitudinal section through a switch in which my invention is embodied in one form;

Fig. 2 is a partial longitudinal section 29 similar to Fig. 1, but showing the toggle members in difierent operative position;

Fig. 3 is a section on the line 33, Fig. 2; Fig. 4 is a dropped perspective of a spring guide pin and associated parts;

935 Fig. 5 is a broken side elevation of a toggle switch of difierent general construction from that shown in Fig. 1, but illustrating the application of the present invention thereto:

gig. 6 is a section on the line 6-6, Fig. 5;

an i

Fig. 7 is a perspective of the kick-01f element of modified form shown in this construction.

It is well known that in electric switches using a toggle mechanism, there is always danger that the contact blade of the switch may become frozen to the stationary contacts of the switch, due to oxidation of the engaging surfaces, or from other causes.

When this occurs, a reversal of the position of the toggle spring fails to effect the throw of the switch bar, since the spring has not sufiicient biasing efiort to overcome the engagement between the frozen surfaces. It is thus impossible to open the switch by the manipulation of the switch-operating means. Dangerous conditions may thus arise which it is impossible to alter, save by opening the circuit at some other point.

I am aware that positive kick-ofi devices have previously been su gested for meeting this dlfiiculty, but these evices have necessi- 7, 1922. Serial No. 599,502.

tated special constructions of the rock lever, switch bar yoke, or other element of the switch mechanism, thus adding to the expense of the construction. By the present invention 1 supply a positive kick-off device which may be applied to any standard switch of the toggle type, in which a guide pin for the toggle-operating spring is utilized.

The invention may be applied to toggle switches of any type, but for the sake of explanation I have illustrated in Figs. 1 to 40f the accompanying drawings, a flush switch of the general construction shown in the copending application of William H. Harrington, filed November 7, 1922, Serial No. 599,499. In a switch of this type the mechanism is mounted in a cup-shaped insulating base 10, in the chamber 11 of which are the fixed contacts 12, 13, with which cooperates the switchbar 14. The latter is carried by a yoke 15 pivoted on the frame 16 and actuated by the toggle spring 17 through the rocker 18 in well understood manner. The switch spring 17 bears at the rocker end against a plate 19, the lugs 20 on which are engaged by the arms of the rocker. Passing through the hole 21 in this plate is the guide pin 22 for the switch spring 17. At its lower end the guide pin has a head 23 which extends through a hole 24 in the cross bar of the yoke 15 against which the marginal lugs 25 of the pin bear. In the present construction, the guide pin 22 is of rectangular section, and is struck from sheet metal.

The throw of the switch bar yoke 15 is limited by the abutments 26 and 27, between which it oscillates. In the present construction the abutments 26 and 27 are formed by downwardly angled lugs from the webs 28 and 29 of the switch frame 16 which overlies the supporting shoulders 30 and 31 upstanding from the bottom of the cup-shaped insulating body 10 of the switch. The present kick-ofi device cooperates with the abutment members, of whatever nature, between which the yoke plays, and is operated by the angular movement of guide-pin 22 incident to the actuation of the rocker 18.

In the form here shown the kick-off device comprises a washer 32 pierced to snugly fit the spring guide pin 22 and forming an abutment against which one end of the switch spring 17 bears. The washer 32 is provided with laterally extending pairs of legs 33 and 34 on opposite sides of the pin 22. As will be observed in Fig. 1, the legs 33 on the side of the washer 32 do not bear against the abutment 26 when the switch is at rest. Their length and position is such that on the throw ofthe switch yoke, the latter, and not the lugs 33, impinges against the abutment. The legs 33 of the washer are thus relieved from any shock of impact. When, however, the rocker 18 is rocked on its axis, the end of the spring guide pin 22 engaged thereby changes its angular position with respect to the switch bar yoke15 since it swings on its lugs 25. The change in angular position of the pin brings the laterally projecting legs 33 of the washer 32 into ongagement with the abutment 26, and the engaging ends of the legs now become a fulcrum and the pin 22 becomes a lever of the first class, to one end of which power is positively applied by the rock lever, while its other end engages the yoke 15 and positively forces the latter away from the abutment 26. This angular displacement of the yoke forces the switch bar 14 positively out of engagement with the fixed contacts 12 and 13, and thus assures the free action of the latter under the-biasing efiort of the spring 17 as the rocker end of the latter is shifted across the axis of oscillation of the yoke. Obviously the same action occurs on the opposite stroke of the switch when the bar is to be moved to circuit-closing position.

In Figs. 5, 6 and 7 the same idea is applied to a switch mechanism in which the insulating body 35 of the switch is of different shape, and the elements of the switch frame and switch mechanism as a whole is of a more usual type of construction. In this form the frame comprises side plates 36 which may be downwardly angled from the supporting member 37, and the switch-bar yoke 38 plays between lugs 39 and 40 at the lower end of the frame plates. The rocker 41 operates the bearing plate 42 at one end of the switch spring in an analogous manner to that first described, shifting it across the axis of oscillation 43 of the switchbar yoke 38. The difference in construction of the kick-off washer 32 is merely that incident to the different type of abutments 39 and 40 between which the switch bar yoke oscillates. Thus, the lugs 44 and 45 are of diflerent shape and spacing from those of the washer 32 first described. Their operation upon the actuation of the rocker is precisely the same, however.

It is clear that instead of adding a washer to the spring pin to efi'ect the kick-off operation, thekick- ofi legs 33, 34 or 44, 45 may be formed as lugs integral with the guide pin 22 itself. Or when the pin has a sliding engagement with the switch-bar yoke, instead of with the rocker, and is forced downward through the yoke on the actuation of the rocker, a cam-llke abutment may be arranged in the path of the rojecting end of the pin which will cause t e latter to exert a like positive freeing effort on the switch-.

bar .yoke. Other ways of accomplishing the result will readily occur to those dealing with the problem, but so far as I am aware, no one has heretofore used the sprin guide pin to effect this action. The particu ar construction shown is merely a convenient one which may be used with standard spring guide pins, but is by no means intended to illustrate the only possible embodiment of the underlying thoughts of what I claim as my invention.

I claim I 1. In an electric switch, a rocker, means angularly displaceable with respect thereto to actuate the rocker, a pivoted switch bar member, .a spring interposed between the rocker and switch bar member and adapted to be shifted at its rocker end across the axis of oscillation of the switch bar member on the actuation of the rocker, a spring guide pin engaging the rocker and switch contact member, a spring abutment member on said pin, and a fixed abutment engaged by said spring abutment member during the oscillation of the rocker and serving to positively initiate the throw of the switch bar member.

2. In an electric switch, a pivoted rocker, a pivoted switch bar member, an interposed switch spring, an abutment therefor having a pivoted engagement with the rocker, a spring guide pin having a sliding engagement with said abutment and an operating engagement with the switch bar member, a fixed abutment and a cam member engaged by said guide pin and moved into engagement with said abutment to positively 1n1tiate the throw of the switch bar member on the oscillation of the rocker.

3.- In an electric switch, a rocker, a pivoted switch bar yoke, an interposed operating spring, a flat metal spring guide pin engaging the switch bar yoke, and a washer mounted on said pin and held against angularvdisplacement with respect thereto, together with a fixed abutment engaged by said washer on actuation of the rocker to positi ely initiate the throw of the switch bar.

4. In an electric switch, a rocker, a pivoted switch bar yoke, an interposed operating spring, a fiat metal spring guide pin en aging the switch bar yoke with limited reedom of angular play therein, and awasher mounted on said pin and held against angular displacement with respect thereto, together with a fixed abutment engaged by said washer on actuation of the rocker to ]positively initiate the throw of the switch 5. In an electric switch, a rocker, a pivoted switch bar yoke, a pivoted abutment member engaging the rocker, a spring guide pin passing freely through said abutment member and having lugs intermediate its ends and engaging the switch bar yoke, a washer slotted to afford a snug engagement with the pin and resting in adjusted position against the lugs thereon, a switch spring interposed between said washer and the abutment pivoted on the rocker, together with a fixed abutment adapted for engagement by said washer to positively initiate the throw of the switch bar yoke on the actuation of the rocker.

6. In an electric switch, a rocker, a switch bar yoke pivoted on an independent axis, a switch spring interposed between the rocker and switch bar yoke and shiftable at its rocker end across the axis of oscillation of the switch bar yoke, a spring guide pin positively engaged with the switch bar yoke, a fixed abutment, and means associated with the switch bar pin engaging said abutment and serving to positively initiate the throw of the switch bar on the operation of the rocker.

In testimony whereof I have signed my name to this specification.

ARVI'D H. NERO.

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