US2242167A

US2242167A - Multiposition electric switch

Info

Publication number: US2242167A
Application number: US303472A
Authority: US
Inventors: Robert H Bentley; Walter L Dietrich
Original assignee: Arrow Hart and Hegeman Electric Co
Current assignee: Arrow Hart and Hegeman Electric Co
Priority date: 1939-11-08
Filing date: 1939-11-08
Publication date: 1941-05-13
Anticipated expiration: 1958-05-13

Description

y R. H. BENTLEY EIAL 2,242,167

MULTIPOSITION ELECTRIC SWITCH 4' Sheets-Sheet 1 Filed NOV. 8, 1959 lNVENTORS YRoBERT H. BENTLEY WALTER L. DIETRICH BY THEIR ATTORNEYS.

May 13, 1941- R. H. BENTLEY ETAL MULTIPOSITION ELECTRIC SWITCH 4 Sheets-Sheet 3 Filed Nqv. 8, 1939 'INVENTORS ROBERT H. BENTLEY WALTER L. DIETRICH BY THEIR ATTORNEYS May 13, 1941. 2,242,167

R. H. BENTLEY ETAL MULTIPOSITION ELECTRIC SWITCH Fil ed Nov. 8. 1939 4 Sheets-Sheet 4 INVENTORS ROBERT H. BENTLEY WALTER L. DIETRICH 3 file-fr a t'l'a r ne ys Patented May 13, 1941 UNITED STATES PATENT OFFICE MULTIPOSITION ELECTRIC swrron Robert H. Bentley and Walter L. Dietrich, Hartf nn, c rs to The Arrow-Hart at Hegeman Electric Company, Hartford, Comp, a corporation of Connecticut Application November 8, 1939, Serial No. 303,472

' 34 Claims.

This invention relates to electric switches. More particularly it relates to electric snap switches of the type inwhich the movable contact is capable of occupying more than two positions. In switches of this typeas heretofore .made, the handle and mechanism couldquickly be run, inadvertently or purposely, in either direction through a second positioninto a third, without stopping in the second position, although 'the purpose of the person operating the switch might not be to go from the original position l to the third position immediately.

Under some conditions, the failure to stop 0 the ability to move directly through the second position 'to another, but when moving in the.

opposite direction the movable contact will be compelled to halt before moving onward into its extreme position. The same may apply if the switch is to occupy more than three positions.

In a three-position switch of this type, it may also be desired that the contact-operatingmember be incapable of movement from an intermediate position back into an extreme position out of which it has just moved, as for example 1 positions of rest.

It is an object 'of our invention to provide an which the mechanism can be moved into more than two positions and in which it is impossible togo from one position to the secondisuocee ing or intermediate position.

switch in which, when the contact-operatingmember is moved in one direction, it is impossible for it to go froma given position to a second improved form of an electric snap switch inposition without stopping in thenext succeeding Another object is to provide amultiposition' succeeding position without stopping in the next (first) succeeding position, but when the contactoperating-member is moved in the opposite direction, it can be moved through an adjacent position without stopping.

Another object is to provide a multiposition switch in which, when the contact operator movies in one direction from one position to another, it is compelled to stop in the second position before continuing onward into a third position, but when the contact operator moves in the opposite direction, it will skip freely through a second position, into a third. I

Another object is to provide a three-position switch in which, (1) when the contact operator moves in one direction from an extreme position, it is impossible for it to go to the other extreme position without stopping in the. intermediate position: (2) when it moves in the other direct1on, it will skip through the intermediate position without stopping; and (3) when it has moved into intermediate position, it cannot be from move into its several positions in sequential order. 1

' Another object is to, provide a multiposition switchin which a movable contact will remain in one position only when manually held there but in which the movable contact can be moved into said position through an adjacent position from a third position only after the movable contact has halted in said adjacent position; and, conversely-as another object-when said movable contact is moved from the position in which it was manually held, it will be halted in an adjacent position in spite of an attempt to move through said adjacent position to -a third position without a halt.

Another object of our invention is to provide an effective and rugged construction of multiposition electric switches of the above and related types which can be made .with a minimum of expense and labor.

Other objects and advantages of our invention will become apparent as it is ,described in. con- Lil nection with the accompanying drawings.

This application is a continuation-impart of our application, Serial -No. 106,923, entitled Three position electric switch," filed October 21, 1936.

In the drawings Fig. 1 is a top plan view of our new improved tically through the invention along line 33 of Fig. 1.

Fig. 4 is a longitudinal section view taken vertically through the invention along line of Fig. 1.

Fig. 5 is a transverse or cross-sectional view of the invention taken along line 55 of Fig. 1;

Fig. 6 is a longitudinal sectional viewtaken vertically through the operating mechanism of our invention and taken along line 6-8 of Fig. 1.

Fig. 7 is a side elevation view of a modified form of motion-limiting mechanism which forms a part of our invention.

Fig. 8 is an end elevation view of the constru tion shown in Fig. 7.

Fig. 9 is ,a longitudinal section view partly broken away, with the section being taken in a plane, such as is indicated by line 9-9 of Fig. 1. but of a' modified form'of the invention.

Fig. 10 is a detailed side elevation view of the operating mechanism of the switch of Fig. 9 with the parts being restrained from moving through mid-position without stopping.

Fig. 11 is a fragmentary detail view of the switch of Figs. 9 and 10 with the parts in midposition. 1 i

Fig. 12 is a view similar to Fig. 10 but of a third form of the invention.

Figs. 13-15 are diagrammatic views of the operating mechanism of the third form of invention, in various positions.

Fig. 16 is a detail view of the handle and cam member used in the third form of invention.

Referring to the drawings, the parts of the switch inall forms of the invention are mounted within a rectangular insulating base In which is hollowed out centrally for the reception of switch operating mechanism, the hollowed out part or recess in the base having parallel endwise extensions (see for example II and I3.) into each corner of the base giving the recess an H-formation. 'One each of four identical stationary wire terminal members 12, I4, I6 and I8 are mounted in each of the four corners of the casing at the end of the aforementioned endwise extensions, these terminals preferably being slipped into vertical slots formed in the walls of said extensions. These terminals, l2 for example, are each stamped from sheet metal into right angular formation with one arm I2, shorter than the other, the short arm having a binding screw l2 threaded therein and accessible through an aperture in the bottom of the base I0. Resilient contact fingers l2, l4, 16, [8 are riveted to the upper ends of the longer arms, for example 12*, of the terminals and extend toward the middle of the base. In the middle or the base at opposite sides ofthe recesses therein are combination terminal and stationary contact members of tridentate form, designated generally by the

numerals

20 and 22. These

members

20, 22 may be identically formed and .iabricated of two elements: one, a contact element, being of resilient metal, stamped into U-shape with the'end portions 20*, 20 functioning as contact fingers; the other 20, a terminal element. may be stamped from sheet metalin a form like l2, l4, l8 and I8. These elements of the

members

20 and 22 are riveted together with the bridge portion of the U across the center of the long l g 01 the terminal, the ends of the resilient contacts l2 and 20' being of size and position to be opposite to each other and likewise will also the end portions of resilient contacts 20 and H 22 and 5, 22' and i8 be opposite.

contact fingers 20 and H (and in like manner contacts i6", 22', I8"- and 22)

movable contacts

24 and 26 are provided. These movable contacts are of sheet metal stamped into the shape of a U with its ends inturned. The contacts are mounted on

sheet insulation slides

28 and 30 at the center of the top edges of the slides in position to engage, in extreme positions, the aforesaid contact pairs. The slides ride on the floor of the base parallel to the side walls and between the 'faces of the aforementioned contact pairs in the manner illustrated most clearly in Figs. 1 and 5 of the drawings.

In order to move the slides in unison there is a pin 32 extending transversely of the base and engaging in recesses 3| in the slides adjacent their bottom edges. This pin 32 is caused to oscillate by switch operating mechanism in such a manner that the pin may occupy a mid-position, as shown in Figs. 1 and 3, and two extreme or end "positions, the right end position being shown in Fig. 6 and the left in Fig. 9.

In all forms the mechanism for operating the switch contacts is mounted upon a frame comprising a pair of

parallel side plates

33 and 34 which are connected at their ends by narrow plates 36 and 3B in a conventional fashion. The mechanism in Figs. 1-8 is operated by an operating lever 40 which is pivoted by a pin 42 positioned diametrically in a metallic nipple 44 mounted centrally in a plate 46 that entends over the top of the switch base In and has between it and the base a centrally perforated insulating plate 48. The plate 46 may be secured to the base by through-bolts 50. The end of the operating lever 40 which extends within the casing has a number of gear teeth formed on it to engage with similarly cut teeth on an operating cam plate 52. This operating cam may be a flat sheet metal stamping of approximately triangu- .lar shape, being rotatably mounted at its apex upon a spindle 54 which in turn is mounted transversely between the side plates of the switch frame. It may now be seen that due to the engagement of the teeth on the operating cam 52 and the operating lever 40 the cam may be rotated about spindle 5| into' various positions.

The bottom edge of the operating cam 52 has a cam surface upon it having arcuate portions '52-, 52 and a central depressed portion or notch 52. When the switch is at rest the operating pin 32 seats in the notch 62.

In order that the operating pin 32 and hence the movable contacts may move with a snap motion, means are provided to keep the movement of the operating handle from being immediately and directly transmitted to the operating pin 32. Thus in the center of the operating cam 52 a strut 56 is positioned by providing a T- shaped aperture in the cam and providing notches in the side of the strut so that the strut may be moved up into the small part of the aperture 52. A pair of wire springs 58 are coiled around the spindle 54 on opposite sides of the operating cam and the ends of these springs engage opposite sides o! the strut 56. The ends of these springs also engage opposite sides of lugs 60 struck out from a fabricated oscillating switching member, which is designated generally by In order to bridge :the pairs of contacts 20*, |2 and the resilient the numeral 62. This switching member is formed of identical sheet metal stampings 64 and 66 having the configuration as may best be seen in Figs. 2 and 6. The upper portions of these stampings are positioned on opposite sides 5 of the operating cam 52 while the lower portions are offset and are secured together by a bracket 58 which has apertures adjacent its opposite ends for the reception of projections on the opposite end of the stampings 85 and 6B. The ends of these projections are peened over to secure the

stampings

64 and 66 and the bracket 58 firmly together but with the stampings far enough apart to permit oscillating movement of the operating mm between the stampings.

Embraced between the lower portions of the

atampings

64 and 66 is a sliding yoke 12 through be lower portion of whose arms passes the operiting pin 32. This yoke is held in position be- :ween the lower ends of the stampings 84 and 56. by means of inturned lugs 14 but the yoke is )ermitted limited sliding movement relative to ;he stampings by reason of elongated slots 15 n the lower portions of the stampings 64 and 65 vithin which slots the end portions of the opertting pin 32 work. A coil spring 78 positioned ietween the bottom of the yoke 12 and the vracket 68 urges the yoke upwardly and the ends f the operating pin into engagement with the op of the slots 18. The whole fabricated switchog member, with the yoke mounted therein as escribed, is pivotally mounted upon the spindle A .To guide the operating pin 32 in its movement here are provided in the side plates of the switch rame identical raceways 80 which have arcuate ortions 80 intersecting adjacent a central ocket 80 and terminating in end pockets 80". 11 the pockets being in the upper surface of the aceways. A peak 80 is formed in the middle of ne lower surface of the raceways.

Assuming that the switching mechanism is in 1e position of Fig. 6, it may be seen that as the erating lever is moved counter-clockwise the oerating cam 52 will move clockwise, its surface Z pushing the operating pin 32 longitudinally l the slots (6 and out of the right-hand pockets l in the side plates of the switch frame. While I moving the operating cam stresses the switch irings 58 which act on the fabricated switchig member 82 tending to move it in clockwise irection. As soon as the operating pin 32 moves it of the right-hand pocket 8i) the switching :ember 62 is free to move and the stress of the vitch spring moves the switching member with snap motion in a clockwise directioncarrying ith it the yoke 12 and the operating pin 32 id thus necessarily the

slides

28 and 30 and re movable contacts 24 and 25 mounted thereon. the operating lever is carried past its midlSitlOI'l, as is quite often the case, the operating .m will likewise be carried past its mid-position id the arcuate surface 52 will be in position prevent the operating pin 32 from coming to the central pocket 80 of the raceway. At .is time the pin 32 will be in position X of Fig.

Thus the switch contacts will be held subantially in mid-position and will not be able pass into an extreme position opposite to that am which they have just'departed until the mdle and operating cams come into their midlsitions, thereby placing the center notch 52 the cam and the center pocket 80 of the plate registry and permitting the operating pin 32 move therein. After this has been accoin- 75 plished the operating lever may be moved in either direction so that either cam surface 52" or 52 will engage pin 32 and move it out of notch to permit the movable contacts to go into either extreme position. as may be desired.

The trivial movement of the movable contacts which may result from the operating pin 32 not being able to immediately fully enter the pockets 80 in the case of over-travel of the handle, is of no importance in the switch illustrated for the reason that the central position is an open-circuit position. However, if it is desired to have the central position a circuit-making position a modified form of stop or over-travel preventing means, as illustrated in Figs. 7 and 8, may be provided.

In this form of the switch the operating mechanism is identical with that just described but the peak 89 is omitted from the raceway in the side plates of the switch frame. in fact the whole lower surface of the raceway is removed and a similar peak N35 is formed upon an additional or auxiliary plate 109 which is substantially in the form of a hollowed out segment. The am:- iliary plate is mounted upon the spindle 54 and is permitted limited oscillating movement so that when the pin 32 strikes the peak Hi8 it will carry that peak and the auxiliary plate lUO slightly away from its center position. This will allow the pin 32 to come into mid-position at once and be ready to move up into the pocket I80 whenever the notch 52 in the operating cam comes in registry with pocket 30. It may be noticed that the pin cannot travel at once over the peak I06 into the arcuate portion I80 of the raceway because the peak and the surface 52 of the operating cam do not afford enough clearance for the pin to pass between them. Stop lugs I01 may be struck from the side plate i34 to limit the movement of the auxiliary plate 100. In order to hold the auxiliary plate normally in mid-position the spindle 54 may be extended far enough through the side plates of the frame to permit a spring I08 to be coiled around the extended end. The ends of the spring will be engaged with the opposite sides of a fixed lug H0 struck out from the frame plate 134 and movable lug 1 42 formed on the auxiliary plate.

To shield the operating parts from the play of any are between the contacts, vertical plates of insulation may be interposed between the contacts and mechanism in the position shown in Figs. 1 and 5.

Referring now to Figs. 9-11, wherein another form of the invention is shown, the operation in this form is similar to that just described in connection with Figs. 7 and'8 except that on moving the contacts into the extreme right position, they will not remain there unless the operating handle is held manually in the extreme left position.

In this form, the gear connection between the I handle and operating member, as shown in Fig. 3,

is omitted and handle 240 (see Figs. 9 and 10) has the cam member 252 rigidly connected thereto. In this form the cam member may be made of two identical plates which are placed back-to-back with their upper ends embedded in the molded composition handle 240. A flange 252 is turnedat right angles to the lower end of each plate forming a cam surface having a profile similar to that of cam plate 52 of Fig. 2. Switching member 62 of Figs. 1-6 has its counterpart in Figs. .9-11 in a one-piece, stamped, sheet-metal, U-shaped switching member 262,

pair of identical plates which are connected by transverse bars adjacent the plate ends, the member being stamped from sheet metal into U-shape. *The ends of'the side plates of the stop member 200 are equally slotted as at 203 to accommodate-guide pins 204 which are positioned transversely in the frame, having their ends secured in the

frame plates

233, 233.

For the purpose of maintaining the stop memher 200 in a certain central position (see Fig. 11) a'spring 208 is wound around one of the pins 204, with the spring endspressing against opposite sides of a strut 2l0 which connects the

side plates

233, 234. The spring ends also embrace a lug 2l2 bent in from one of the comers of the stop plate 200 (adjacent the left end in Fig. 9). Thus if the lug H2 and stop plate move to the'right or left, the spring 208 will tend to return the stop member to central position.

' In order that the switching member 262 shall not remain in the extreme right-hand position except when the handle is held manually in the extreme left, a spring 253 is wound around the pivot pin 254 of the switching member. One end 259 of the spring presses against the cover 246. The other end 259 of the spring presses against a lug 256 struck out of the cam operating member 252. The effort of the return spring 259 is adequate to move the operating handle and cam operating member to shift the switch operating member into mid-position as shown in Fig. 11 because of two factors: (1) the strength of the spring itself, which need be only strong enough to move the pin 32 along the cam surface 280 into the,pcket 280; (2) the surface 280 is straight and does not terminate in a pocket as does the surface 280 (which is equivalent to ,surface 80' in Figs. 1-6) so that little invention shown in Figs. 1-8, the operation of the form of Figs. 9-11 may-be understood. when with ears 268 bent up from the transverse bot- Due to the fact that there is practically no resistance to the movement of pin 32 from notch 230 as the handle is moved (either under the effort of the spring 253 or by manual force) the handle and switching member 262 and operating pin 32 move as av unit as' the pin 32 moves from notch 280 to mid-position.

It will be noted that in Figs. 9-11, the switch operating mechanism and contacts are capable of coming to restin three distinct positions, although in one position manual force must be applied to the handle. to prevent the spring 263 from moving the handle and thus actuating the operating mechanism from one of its positions.

Referring now to Figs. 12-16, the construction of the operating mechanism is generically the same as in Figs. 9-11, but differs therefrom in the shape of the cam operating member 352 in order to require movement of the switch into its positions sequentially, as hereinafter described. In function, Figs..12-16 differ from the other forms of the invention, firstly in the respect that in moving from right to left, the pin '32 stop, although the switch mechanism must halt in mid-position as the operating pin'32 moves from left to right as in all the other forms of the invention. The switch parts will remain in all of the three positions without manual assistance. Secondly, when the pin is in midposition, .it cannot be moved back to the left end-position but it must go into the right endposition first, and only'then can it be moved into the left end-position, skipping through -midposition on the way.

In structure, the stop member 302 of Fig. 12

differs from similar stop member 202 ofFlgs. 9-11'in that slot 303" at the left end of said member is of less length than the slot 303" at the right end (which is the same length as slot 203 of Figs. '9-11). Also the rightsurface of the projection 306" and the left surface of the pocket 380 are so formed that when' the pin 32 hits the right side of the projection (in moving from right to left) and carries the stop member 302 to the left until the end of slot 303* abuts the cross pin 208, there will still be room enough between the surfaces of the stop member and the adjacent surfaces of the frame to permit passage of pin 32. Hence pin 32 will not be halted in mid-position in passing from right to left. To

facilitate the pin skipping through center in going from right to left, the left surface of pocket 380 may be inclined, as illustrated in Fig. 12, so as to the switching member moves from the position of Fig. 9 to the right, it must .halt in mid-position because the projection 206 on the stop member 200, upon being abutted by pin 32, moves to the right and prevents passage of the pin 32 (see Fig. 10) until the pin seats in pocket 280 and releases stop member 200 (see Fig. 11). Then,.

on moving the switch handle to theextreme left, pin 32 is caused to move to the right pressing down on the right hand slope of the projection and moving the stop member to the left, the

pin 32 thus making way for itself to move against reduce friction and facilitate movement of the pin across the surface out of the pocket and into the next position. The spring for causing the Y snap movement of the contacts should be made strong enough to cause the pin to carry through mid-position by its own momentum, even though the handle has been moved only normally and has not been caused to over-travel substantially. On the other hand, pin 32 will be halted in passing from left to right because the left surface-.of projection 306 and the right surface-of pocket 380 are the same as in Fig. 10, and slot 303 the same as 203.

Switches of the type of Figs. 12-16 find a wide field of use in starting motors. In such case.

the extreme right position of pin 32 (when located-in notch S as in Fig. 14) is the starting" position and the extreme left position (with pin 32 in notch R.) .is the .running position. Midtpiosition (as shown in Fig. 12) is the stop" posi- In order to malre it impossible to move the switch into "running" position, directly from 352' of the cam operating member, from the center toward the right end (see Fig. 16) sufilciently to prevent that surface of the cam from moving the pin 32 out of the pocket 380 when th handle 240 is moved to the right (see Fig. 13). Thus, the handle will abut the right end of the slot in the casing cover "8, through which the handle projects, and will be halted, as shown in Fig. 13, before the cam surface 352 has moved the pin 32 far enough to disengage itself from the pocket 380. Therefore, movement of the pin 32 from mid-position (Fig. 12) to extreme left position cannot be directly accomplished. The

pin must first move into extreme right-position (Fig. 14) and then skip through center to extreme left-position. The cut away portion 352* of the operating cam does not prevent movement of the mechanism from starting" position (Fig. 14) to running" position because the cam and handle move through twice the are (equal to movement through two positions) in that case that they do in moving from stop" position (or mid-position of Fig. 12) toward running position. Hencethe end of the cam surface 352' comes into play and disengages pin 32 from the notch S (see Fig. 15 wherein this action has just taken place) so that the switch spring (see 58 in Fig. 6) can skip the pin 32 through midposition to the left notch R. Operation of the V pin 32 from left to right (Figs. 12-15) is normal,

1. e., into mid-position and halts there, and then moves into extreme right, just as in Figs. 1--ll. From the foregoing, it can be seen that the switch of Figs. 12-16 must move sequentially through its various positions from. stop" to starting to running and back to stop. The

switch can move no other way.

It the cam surface 352 beflnot cut away, the

switch will then be able to operate directly from mid-position into either end-position.

From the foregoing, it may be seen that we have provided switch mechanisms which are capable of moving a movable contact into more than, two positions and in which it is impossible, by over-throw of the operating handle, to move the movable contact from one position through the next position into a second succeeding position without stopping in that next or intermediate position.

We have also provided multiposition switches which, prevent movement through adjacent positions when moving continuously in one direction but permit movement through adjacent positions when moving in the other direction. We have also provided a switch in which the contact operator cannot be returned directly from midposition to the end-position irom whence it came, but can be moved into that end-portion only after going through each of its other posi tions sequentially.

It will be observed that in each of the forms of the invention. the contacts may come to rest in'three distinct positions, but in one form, the

handle has only two positions of rest and maybe held in a third position to allow the contacts to remain in their third positionoi rest.

means for operating the switch, and means in embodiments of the invention as illustrated and described.

What is claimed is:

1. In an electric switch, fixed and movable switch contacts, meansjto move said movable contact into more than two positions of rest, handle means for operating the. switch and means including stationary and movable members cooperating to prevent said movable contact upon moving from one position toward'an-adjacent position from moving through said adjacent position without remaining therein when said handle means is made to over-travel substantially in an effort to move said movable contact through said adjacent position without stopping, the cooperation of said stationary and mov. able members being independent of current flow in the switch.

2. In an electric switch, fixed and movable switch -contacts, means to move said movable contact into more than two positions of rest, handle means for operating the switch, and means including cooperating members at least one of which is movable and engageable by a part of 'said movable contact-moving means, and effective upon operation 01' 'the switch to halt said movable contact in the position of rest ad jacent its starting position, when said handle means is made to over-travel substantially, in an effort to move said movable contact through a position adjacent the starting position without stopping therein, the operation of said cooperating members being independent of current flow in the switch.

3. In an electric switch, fixed and movable switch contacts, means to move said movable contact into more than two positions of rest, handle cluding a member movable with. said handle means upon operation of the switch to halt said movable contact in the position of rest adjacent its starting position when said handle means is made to over-travel substantially in an effort to 'move said movable contact through a position adjacent the starting position without stopping therein.

The principles of the invention are-applicable j to switches having more than three Many otherforms within the scope our invention will occur to'those skiliedin'the- Therefoi'e we do not limit ourselves to the 7s 4. In an electric switch, fixed and movable switch contacts, means to move said movable'eontact into more than two positions of rest, handle means for operating the switch, fixed stop means, and means movable with said handle means upon operation of the switch and cooperating with said stop means to halt said movable contact in the position of rest adjacent its starting position in case of unlimited over-travel of said handle means.

5. In an electric switch, fixed and movable switch contacts," means to move said movable contact into more than two positions of rest, handle means for operating the switch, a projection,

' and means movable with said handle means upon member into and out of morethan two positions ot with a nap motion. and means controlled by over travel ofsaid handle means to cause said mar a, e-contact operating means-to halt in the position ofrestfadiacentits starting position,-

whereby snapping of said movable-contact-operating means through said adjacent position, due

to over-travel of said handle means, is prevented.

stop means to halt said movable-contact-operating member in the position of rest adjacent its starting position irrespective of the degree of over-travel of said handle means.

8. In an electric snap switch, fixed and movable switch contacts, a movable-contact-operating member, handle means for operating the switch, means to move said movable-contactoperating member into and out of more than two positions of rest with a snap motion including stationary means having a raceway therein, means actuated by said handle means for movement along said raceway, and means cooperating with said handle-actuated means and raceway to halt said movable-contact-operating means in the position of rest adjacent its starting position irrespective of the degreeof over-travel of said handle means. I

9. In an electric snap switch, fixed and movable switch contacts,, a movable-contact-operating member, handle means for operating the switch, means to move said movable-contactoperating-mem-ber into and out of more than two positions of rest with a snap motion including stationary means having a raceway therein, means slidable along said raceway but normally held in a position of rest at any one of certain points along said raceway, said slidable means being moved along said raceway with a snap, and means cooperating with said slidablemeans to halt said slidable means at one of said points adjacent its starting point when said handlemeans is made to over-travel substantially in an effort to move said movable-contact-operating member through a position adjacent the starting position without stopping therein.

' 10. In an electric snap switch, fixed and movable switch contacts,,,;a movable-contact-operating member, handle means for operating the switch, means to move said movable-contactoperating member into and out of more than two positions of rest with a snap motion including stationary means having a raceway therein, means movable along said raceway and adapted to engage with said raceway at certain points to retain said movable-contact-operating means in its positions of rest, means on said raceway to halt said movable-contact-operating means in a position of rest adjacent its starting position when saidhandle means is made to over-travel substantiallyin an efiort to move said movablecontact-operating means through a position adjacent the starting position without stopping therein.

11. In an electric snap switch, fixed and movable switch contacts, a movable-contact-operating member, handle means for operating the switch, means to move said movable-contactoperating member into and out of more than two positions of rest with a snap motion including resiliently mounted movable means, stationary means engaged by said resiliently mounted means, means in said stationary means receiving said certain positions of rest, and means operated by said handle means to release the engagement of said resiliently mounted means and said stationary means and to free said resiliently mounted means for movement into another position, and means on said stationary means to halt said resiliently mounted means in the position of rest adjacent its starting position, when said handle means is made to over-travel substantially in an efiort to move said movable-contact-operating member through a position adjacent the starting position without stopping therein.

12. In an electric snap switch, fixed and movable switchcontacts, a movable-contact-operating member, handle means for operating the switch, means to move said movable-contactoperating member into and out of more than two positions of rest with a snap motion including resiliently mounted movable means, stationary means engaged by said resiliently mounted means, means in said stationary means receiving said resiliently mounted means to retain the latter in certain positions of rest, and means operated by said handle means to release the engagement of said resiliently-mounted means and said stationary means, and to free said resiliently mounted means for movement into another position, means on said stationary means cooperating with said releasing means to halt said resiliently mounted means in the position of rest adjacent its starting position when said handle means is made to overtravel substantially in an eii'ort to move said movable-contactoperating member through a position adjacent the starting position without stopping therein.

13. In an electric snap switch, fixed and movable switch contacts, handle means for operating the switch, means to move said movable switch contact into and out of more than two positions of rest with a snap motion including a switch frame, movable means resiliently eng said frame, means on said frame to receive and position said resilient movable means in certain positions of rest, means operated by said handle means to disengage said resilient means from said frame and cause movement of said movable contact intoanother position, and means on said frame cooperating with said disengaging means to halt said movable contact in the position of rest adjacent its starting position irrespective of the degree of over-travel of said handle means.

14. In an electric switch, fixed and movable contacts, a movable-contact-operating member, means to move said movable-contact-operating member into more than two positions of rest. handle means for operating the switch, and means normally permitting movement of a portion of said movable-contact-moving means in a predetermined path and responsive to overtravel of the handle to restrict said path and halt said movabie-contact-opcrating member in a position of rest adjacent its starting position.

15. In an electric switch, fixed and movable I contact means, means to move said movable concontact means in a second switch position, which I 15 intermediate its starting position and a third switch position, when said handle means is made resiliently mounted means to reialn thelatter in ii; to over-travel in an eiiort to move said movable contact through said second position without stopping therein, said cooperating'members continuing to halt said movable contact means so long as said handle ismaintained in overtraveled position, and the operation of saidcooperating members being independent of current flow in the switch.

16. In an electric .switch, fixed and movable contact means, means to move said movable contact means with a snap motion into more than two switch positions, at least two of which are conducting positions, handle means, a fixed member, a movable member cooperating with said fixed member and having a projection movable upon engagement by a part of said movablecontact-moving means to restrict the passageway of said part and to require said movable-contactmoving means to halt in a second switch position, which is intermediate its starting position and a third switch position, when said handle means is made to over-travel in an effort to move said movable contact through said second position without stopping therein, the operation of said cooperating members being independent of current flow in the switch.

17. In an electric switch, fixed and movable contacts, contact operating means movable into three switch positions, handle meanspmeans providing a fixed guide surface for a part of said contact operating means, means movable relative to said fixed guide surface and capable of being moved independently of said handle means and providinga movable surface, engageable by said part of the contact operating means, said movable surface cooperating with saidfixed surface to restrict the passage of said part of the contact operating means to require said part to halt in a second switch position, which is intermemediate its starting position and a third switch position, when said handle means is made to over-travel in an effort to move said movable contact through said second position without stopping therein, the operation of said cooperating members being independent of current flow in the switch.

18. In an electric switch, fixed and movable contact means, means to move said movable contact means with a snap motion into more than two switch positions, at least two of which are conducting positions, handle means, and means including cooperating members at least one of which is movable and engageable by a part of said movable-contact moving means and eiIe'c-' tive on operation of the handle means in one direction only to halt said movable contact means in a second switch position, which is intermediate its starting position and a third switch position, when said handle means is made to over-travel in an effort to move said movable contact through said second position without stopping therein, the operation of said co-opcrating members being independent of current flow in the switch.

19. In an electric switch, fixed and movable contacts, contact operating means movable into three switch positions, handle means, means providing a fixed guide surface for a part of said contact operating means, means movable relative to said fixed guide-surface and capable of; being moved independently of said handle means and providing a movable surface ble by said part of the contact means, said movable surface cooperating with said fixed surface, butonli whensaidhandlemeans ismovedin ofsaid 75 a certain direction.

part of the contact operating means to require said part to halt in a second switch position, which is intermediate its starting position and a third switch position, when said handle means is made to over-travel in an effort to move said movable contact through said second position without stopping therein, the operation of said cooperating members being independent of current flow in the switch.

20. In an electric switch, fixed and movable contact means, means to move said movable contact means with a snap motion into more than two switch positions, at least two of which are conducting positions, handle means, and means a third switch position, when said handle means is made to over-travel in an effort to move said movable contact through said second position without stopping therein, the operation of said cooperating members being independent of current flow in the switch, and means to automatically return said movable contact means to said intermediate position upon release of said handle means.

21. In an electric switch, fixed and movable contacts, contact operating means movable into three switch positions, handle means, means providing a fixed guide surface for a part of said contact operating means, means movable relative to said fixed guide surface and capable of being moved independently of said handle means and providing a movable surface engageable by said part of the contact operating means, said movable surface cooperating with said fixed surfacewhen said handle means is moved in a certain direction, to restrict the passage of said part of the contact operating means to require said part to halt in a second switch position intermediate its starting position and a third switch position, when said handle means is made to overtravel in an effort to move said movable contact through said second position without stopping therein, the operation of said cooperating members being independent of current fiow in the switch and spring means to automatically return said movable contact means to said intermediate position upon release of said handle means, said fixed guide surface being formed to facilitate said return.

22. In an electric switch. fixed and movable contact means, means to move said movable contact means with a snap motion into more than two switch positions. handle means, and means including cooperating members at least one of which is movable and engageable by a part of said movable-contact-moving means and efl'ective on operation of the handle means in one direction only to halt said movable-contact means in a second switch position, which is intermediate its starting position and a third switch position, when an effort is made to move said movable contact through said second position without stopping therein, and means causing said movablecontact moving means to move through said intermediate position without stopping when said handle means is operated in the other direction.

23. Inan electric switch, fixed and movable contacts, contact-operating means movable into three switch positions, handle means, meanspmviding a fixed guide surface for smart of said contact-operating means, means movable relative to said fixed guide surface and capable of being moved independently of said handle means and providing a movable surface engageable by said part of the contact-operating means, said movable surface cooperating with said fixed surface, but only when said handle means is moved in a certain direction. to restrict the passage of said part of the contact-operating means to require said part to halt in a second switch position, which is intermediate its starting position and a third switch position when an effort is made to move said movable contact through said second position without stopping therein, said fixed and movable surfaces being constructed and arranged to cause said movable-contact-moving means to move through said intermediate position without stopping when said handle means is operated in the other direction.

24. In an electric switch, relatively movable contacts, contact-moving means adapted to oc- 'cupy'morethan two 'positionsy'at least two of which are conducting positions, means compelling said contact-moving means to halt in a second position intermediate its starting position and a third position as said handle means is moved in one direction notwithstanding that said handle means is made to over-travel in an efiort to move said contact-moving means through said second position without stopping therein, and means causing said contact-moving means to skip through an intermediate position on reverse operation of said handle means.

25. In an electric switch, relatively movable contacts, contact moving means adapted to occupy more than two positions, at least two of which are conducting positions, means compelling said contact-moving means to halt in a second position intermediate its starting position and a third position as said handle means is moved in one direction notwthstanding that said handle means is made to over-travel in an effort to move said contact-moving means through said second position without stopping therein, and means permitting said contact-moving means, upon reverse operation of said handle means. to move through an intermediate position when said handle means is caused to overtravel during said reverse operation.

26. In an electric switch, relatively movable contacts, contact-moving means adapted-to occupy at least three positions, means compelling contact-moving means to halt in a second position intermediate its originarposition-and a third position as said handle means is moved in one direction, notwithstanding that the handle means is made to over-travel in an effort to move said contact-moving means through said intermediate position without stopplng therein, and means preventing reverse movement of said contact-moving means directly back into said original position from said intermediate position.

27. In an electric switch, relatively movable contacts, contact-moving means adapted to occupy at least three positions, means compellinr 'g said contact-movingmans to halt in a second position intermediate its original position and a third position as said handle means is moved in one direction, notwithstanding that the handle means is made to over-travel in an. effort to move said contact-moving means through said intermediate position without stopping therein, and means requiring said contact-moving means to be moved into said third position before it can be moved back into said original position.

28. A switch as claimed in claim 26, including means to cause said contact-moving means to move from all its positions with a snap motion.

29. In an electric switch, relatively movable contacts, contact-moving means adapted to occupy at least three positions, means compelling said contact-moving means to halt in a second position intermediate its original position and a third position as said handle means is moved in one direction, notwthstanding that the handle means is made to over-travel in an eflort to move said contact-movin means through said intermediate position without stopping therein, and means preventing reverse movement of said contact-moving means directly back into said original position from said intermediate position, and means causing said contact-operating means to skip through an intermediate position on reverse movement of said handle means from a position beyond said intermediate position.

30. In an electric switch, relatively movable contacts, contact-moving means adapted to 0ccupy at least three positions, means compelling said contact-moving means to halt in a second position intermediate its original position and a third position as said handle means is moved in one direction, notwithstanding that the handle means is made to over-travel in an eflort to move said contact-moving means through said intermediate position without stopping' therein, and

' means preventing reverse movement of said contact-moving means directly back into said original position from said intermediate position, and means permitting said contact-operating means to move through an intermediate position without stopping therein, on reverse movement of said handle means from a position beyond said intermediate position.

31. A switch as claimed in claim 29, including means to cause said contact-moving means to move from all its positions with a snap motion.

32. A switch as claimed in claim 30, including means to cause said contact-movin means to move from all its positions with a snap motion.

33. In an electric switch, relatively movable contacts, contact-moving means adapted to 00- cupy at least three positions, means compelling said contact-moving means to halt in a second position intermediate its original position and a third position as said handle means is moved in one direction, notwithstanding that the bandle means is made to over-travel in an eflort to move said contact moving means through said intermediate position without stopping therein, and means requiring said mechanism to come to rest in said original intermediate and third positions in that order, as the switch is operated.

A-switch as claimed in claim 33, including means to cause said contact-moving means'to move from all its positions with a snap motion.

ROBERT H. BENTLEY. WALTER L. DIE-TRICK.