US2616012A - Locking teeter-bar switch - Google Patents

Description

Oct. 28, 1952 A. c. GAYNoR I LOCKING TETER-BAR SWITCH Filed Sept. 20, 1949 nventor Patented Oct. 28, 1952 f n ,l UNITED STATES PATENT OFFICE AArthur C. Gaynor, Stratford, Conn. l Application September 20, 1949, Serial No."116,f778 i' 'v 4 Claims. (Cl. 20G-169) This invention relates to electric switches, and more particularly to snap or toggle switches of the rtype having a teeter bar as an operating member. Y

Small toggle lor snap switches are commonly used for appliances, electric typewriters, accounting and other business machines to switch these on and off. At times the operator of the machine finds it necessary to leave the machine with work in it, 'and under such circumstances it is highly desirable to prevent casual, inadvertent, or mischievous operation of the machine during the opera-tors absence. For example, in bookkeeping, tabulating or adding machines, and also in typewriters, during the operators absence the machine might be operated by another accidentally or unintentionally and cause the work to be spoiled or inaccurate. This may or may not be noticed by the voperator upon his return, and in either eventhas undesirable consequences.

An object of the present invention is to provide an improved and simplified on-and-off, toggle or snap switch, particularly for electric appliances, business machines and the like, which may be very easily and quickly locked in its oi position so as to discourage tampering' with the machine or accidental operation of the machine during an operators absence.

Another object of the invention is to provide an. improved toggle or snap switchadapted. for the above purpose, which may be locked in either its off or on position. A further object of the invention is to provide an improved locking-type electric switch -as characterized above, which is extremely simple in construction and economical to fabricate.

A still further object of the invention is to provide an improved electric switch in accordance with the foregoing, which may be very quickly and easily locked or unlocked by the operator.

In accomplishing the above objects I provide a toggle or snap switch mechanism mounted in a casing which may be either of the panel-mounting type or the feed-through type. The .casing carries a teeter-bar operator for the switch mechanism, 4adapted to occupy different on and "ofP positions. On portions of said teeter bar and casing I provide cooperating means for releasably locking the bar in one or the yother of vits positions, against casual movement. To yactuate the locking means a manually-operable member, preferably in the form of a recessed head stud, is provided, which is rotatably carried by the teeter. bar operator. The locking -2-.2 in this figure.

.bar of the 4switch fof Fig; 1l

means, in the embodiments of theinvention i1- lustrated herein, comprises a lug on the teeter bar and a -cooperable shoulder on the casing, the said lug being actuated in response to movement of the recessed head studs.

When it is desired to lock the switch in either off or on position, I provide duplicating locking and actuating assemblies on the teeter bar and'casing, which may be made operative for either position of the teeter bar.

Preferably the recessed head studs are of the type known commercially as Allen head, that is, they have hexagonal recesses requiring an hexagonal key to operate them. Therefore a person other 'than the Ioperator of the machine cannot empl-oy devices such as nail iiles, screw drivers and the like to unlock the switch, but will need a proper-fitting hexagonal key, such as an Allen key. f

Other features and advantages will -herein after" appear.

In the accompanying drawings:

Figure 1 isia longitudinalv` sectional -view vthrough an' improved teeter-bartoggle switch .feed-through type.

Fig. 2 is .an inside plan view of the upper half of the switch of Fig. l, indicated by the lines Fig. 3 is a fragmentary plan'view of the-teeter z Fig. 4is a fragmentary longitudinal sectional view of at'eeter bar operator illustrating another yembodiment of the invention wherein the teeter bar may be locked either in off or on position. 1

Fig.; 5 -is a view like Fig. 1 but illustrating a panel-type switch, and further illustrating a modified form of l-ocking means; and

Fig. 6 is a fragmentary detail, in perspective, of the locking meansshown in Fig. 5.

Referring to Figs.' 1 and 2 the improved locking toggle switch shown therein comprises a casing l0 having la lower part Il and an upper part I2 4secured together by the usual draft screws. Within the casing 'Ill an electric switch mecha.- nism I3 is provided,- having a 'switch blade I4 and a toggle or snap mechanism i5 which is actuated by a finger I6 of a teeter bar I1 pivotally xcarried by the casing part I2.

As shown in Fig. 3, the teeter bar l1 may have the indicial off and fon respectively on its faces I8 and IS, the said faces being angularly disposed f with respect to each other and so arranged that,

for..the two possible positions of the teeter bar,

3 one Ior the other faces I 8, I9 is flush with the exterior of the casing partfI 2.

For the purpose of providing a simple Iand effective locking means whereby the teeter bar I1 may be locked in off position, I provide a manually operable member 20 in the form of a recessed head Allen-type stud which is rotatably carried by the lef-t-end portion of the teeter bar II, as viewed in Fig. 1. The head of the stud 20 is recessed into the teeter bar so' that the face of ythe stud is substantially iiush with the surface I 8 of the bar.

At its lower end the stud 20 mounts a lug 2I which extends laterally from the shank of the stud a distance suiiicient to enable itV to project into a recess 22, Fig. 2, in the casing l0. As shown in Fig. 1, the recess 22 has an upper wall 23 which constitutes a shoulder arranged to be engageable with the lug 2| when the latter is in a locking position shown in Fig. 2. The shape of the lug 2I is such that. when the stud 2Ilis rotated to bring the lug into the dot-and-dash position 4`v shown in Fig. 2, the lug will not project into the recess 22,. but, instead, will clear the shoulder 23, thereby enabling the teeter bar I'.' to be freely operated to aotuate the switchfrom oi to-on and vice versa. When, however, the lug 24' is in the position shown in Fig. 2, the teeter bar II will be locked inthe off position of Fig. 1, and a person cannot either casually or inadvertently or intentionally operate the switch to on position unless he first turns the stud 2D to bring theA lug 2-IV to the unlocking position 2li.

Thus an operator of the machine which has the present improved locking switch may take the precaution of preventing his machine being operated during' his absence by merely inserting an Allen wrenchA in the recessed head of the stud 20 and turning it to lock vthe switch in its off position.

Since a small hexagonal tool or instrument having the shape of an Allen wrench is relatively uncommon. in ofces and the like, a person desiring" to operate theA switch willflnd it diicult to do so if he does not have the properwrench to perform the unlocking operation. Instruments such as screw drivers, nail files: and the like will not? be eiective to 'turn the stud 28,. particularly since the hexagonal recess thereof is of extremely small dimension.

I have thus provided, by the above structure, anv extremely simple and practical means. for locking. an appliance or business-machine switch in its on position.y Relatively few parts are involved in. the locking means and therefore it may be easily and quickly fabricated at low cost. Moreover it may be very easily' or conveniently actuated by the operator! of the machine, requiring only the possession of the proper size Allen wrench or key'.

yAnother embodiment of the invention is shown in Fig'. 4 wherein a teeter bar 26 is provided, having' at both its ends recessed-head studs Z'I and 28 carrying locking lugs 29` and 30 respectively. The lug 29 may be swung to project it into a recess 3l in the casing part 32 of the switch, to engage a shoulder 33 formed by a wall of said recess. Likewise the lugv 30 carried by the stud 28 may be swung to project it into a recess 34 in the casing part 32, having a` shoulder' 35 for engagement by said lug.

According to this construction the. teeter bar 26 may be locked in either its on or "o1T. position.

A modiiication of the invention is shown; in

Figs. 5 and 6. In these figures the teeter bar 36 carries a recessed-head stud 31 provided at its inner end with a tab or blade 38 having oppositely disposed notches 39 providing undercuts. The stud 31 has a press-fitted collar 31a t0 retain it in place on the teeter bar 36.

The switch of Figs. 5 and 6 has a casing 4G provided with an insert 4I in the form of a socket-shaped member having a slot 2 adapted to receivey the blade S of the stud 37. As shown in Fig. 5, when the teeterA bar 35 isV in the off position, the blade or key 38 will extend into the socket member t! through the slot 42 thereof, and4 if the stud 3T should be turned to the position shown in Fig. 5, the key 38 will become locked. tothe member 42 and prevent actuation of the teeter bar 35.

While I have shown the studs 2t, 2'I, 28 and 3l as being of the recessed-head Allen type, obviously other recessed members may be substituted therefor, requiring special or odd shaped keys, and tumbler locks may also be used. where it is imperative that inadvertent or casual operation of the switch be prevented.

Variations and modications may be made within the scope of the claims and portions of the improvements may be used without others.

I claim:

l. In an electric switch having a casing, a switch. mechanism in the casing and a teeter bar mounted on the casing for movement between on and off positions, said bar actuating said mechanism, the improvement which comprises: cooperating means on portions of said teeter bar and casing, inaccessibly located Within the casing, for releasably locking the bar in one of its positions on the casing, said means comprising a movable lug on the bar and a shoulder on the casing alongside the bar, engageable by said lug when the latter is projected from the side of the bar; a. member movably mounted on one of said portionsv of the casing or teeter bar, said member beingr shaped and located to prevent its being grasped by hand. and having means engageable by a key to move-the member; and means controlling said movable lug in response to movement of said member.

2. In an electric switch having a casing, a switch mechanism in the casing and a teeter bar mounted on the casing for movement between on and oi positions, said barV actuating said mechanism, the improvement which comprises: a member movably mountedy on said teeterbar, said member being shaped and located to prevent its being grasped by hand and having means engageable by a key to move the member; and means on said bar and casing, inaccessibly located within the casing, for releasably locking the bar in one of its positions in response to actuation of said member, said means including a movable lug on the teeter bar, actuated by said member and projectable from the side of the bar, and including a shoulder on the casing alongside the teeter bar, engageable by said lug when the latter is projected.

3. In an electric switch having a casing, a switch mechanism in the casing and a teeter bar mounted on the casing' for movement between on and off positions, said bar actuating said mechanism, the improvement which comprises: cooperating means on portions of said teeter bar and casing, inaccessibly located within the casing, for releasably locking the bar in one of its positions on the casing, said means comprising a movable abutment on the bar and a cooperating ARTHUR C. GAYNOR.

6 Y REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date f 619,233 Schraudner Feb. 7, 1899 728,590 Linn May 19, 1903 1,366,504 Sessions Jan. 25, 1921 1,527,624 Blake Feb. 24, 192,5 1,684,983 Clark Sept. 18, 1928 1,852,772 Gaynor Apr. 5, 1932 2,006,129 Craft June 25, 1935 2,055,688 Halinka Sept. 29, 1936

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