US633771A - Switch for electric circuits. - Google Patents
Switch for electric circuits. Download PDFInfo
- Publication number
- US633771A US633771A US70378399A US1899703783A US633771A US 633771 A US633771 A US 633771A US 70378399 A US70378399 A US 70378399A US 1899703783 A US1899703783 A US 1899703783A US 633771 A US633771 A US 633771A
- Authority
- US
- United States
- Prior art keywords
- lever
- arm
- switch
- base
- contact member
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H19/00—Switches operated by an operating part which is rotatable about a longitudinal axis thereof and which is acted upon directly by a solid body external to the switch, e.g. by a hand
- H01H19/54—Switches operated by an operating part which is rotatable about a longitudinal axis thereof and which is acted upon directly by a solid body external to the switch, e.g. by a hand the operating part having at least five or an unspecified number of operative positions
- H01H19/56—Angularly-movable actuating part carrying contacts, e.g. drum switch
- H01H19/58—Angularly-movable actuating part carrying contacts, e.g. drum switch having only axial contact pressure, e.g. disc switch, wafer switch
Definitions
- Our invention relates to switches for electric circuits; and it has for its object to provide a switch of such construction that its movable contact member may be readily [5 brought into operative position, locked in such position, and released and separated from its stationary member by an expenditure of power that shall be substantially independent of the current-carrying capacity of the switch and much less than that exercised in opening and closing switches of the types heretofore employed.
- Manually-operated switches heretofore in use have generally been of knife-blade and jaw construction, the structures being variously modified in order to increase the current-carrying capacity and facilitate the opening and closing of those of large size.
- the opening and closing of knife-and-jaw switches 0 having large current-carrying capacity can be eifected, however, only by the application of a considerable amount of power by reason of the fact that the jaws must contain so much material that they will yield to only a very lim- 5 ited degree.
- Figure 1 is a side elevation of one form of switch constructed in accordance with our invention
- Fig. 2 is a front elevation of the same on a smaller scale
- Fig. 3 is a side elevation of a switch having a modified form of operating and locking mechanism
- Fig. i is a front elevation of the same on a smaller scale.
- FIG. 5 is a side elevation of a double-throw switch constructed in accordance with our invention
- Fig. 6 is a front elevation of the same
- Fig. 7 is a detail view of the locking-head forming part of the switch mechanism shown in Figs. 5 and (5.
- Fig. l l is a supporting-base, which will ordinarily be a switchboard-panel of marble, slate, or other similar material.
- terminal studs which extend through the base-plate l and are respectively provided on the face of the latter with contact plates or blocks i and f, having flat eontact-surfaces parallel with the face of said base-plate.
- Attached to the terminal block i or to the base 1 adjacent to said terminal block are two forwardly-projecting plates 5, to the outer or lower end of each of which is pivoted an arm 6, the other ends of said arms being bolted or otherwise rigidly fastened to the movable contact member7ol'the switch.
- This movable contact member '7 is built up of thin plates bolted or riveted together at or near their middle portions and terminating at each end in a plane that is substantially parallel to the faces of the terminal blocks or plates i and 4; when said member is brought nearly to its circuit-closing position.
- An operating arm or lever 8 provided with a suitable handle 8, is formed with two curved arms, the ends of which are respectively pivoted to the plates 5 at points materially nearer to the middle of the brush-contact member '7 than the pivotal points of the arms 6.
- a toggle-lever arm 9 is hinged or pivoted at one end to the lever S and at its other end to the arms (3, at such 5 points that when the switch is in its closed position the axis of the pivotal connection with the arms (3 will be slightly below a straight line joining the pivotal axis of the lever S and that between the 1everarm.)and 10o said lever 8.
- the contact member 7 is pro vided with a lug or projection and the opcrating-lever 8 with asimilar lug 11, this being so located and of such dimensions that they will come into engagement when the movable member of the switch has been moved to its locked position.
- the toggle-lever operating mechanism for the movable member of the switch is such that the switch may be very easily opened and closed irrespective of its size and carrying capacity and that when closed it will be locked and firmly held in that position by reason of the toggle-joint between the movable contact member and its operatinglever having passed slightly beyond the deadcenter.
- the base plate or slab 1, the terminal studs 2 and 3, and their contact blocks or plates a and a are or may be the same in construction and arrangement as the corresponding parts shown in Figs. 1 and 2.
- the plates 5", constituting, the supporting-frame for the toggle-lever mechanism, perform the same function as the parts 5 shown in Figs. 1 and 2; but on account of differences in the structure and arrangement of the toggle-lever mechanism these parts are shown in Figs. 3 and 4: as of different form.
- the supporting-arm 6 is pivotally mounted at one end between the plates 5 and is attached at its other end to the lam inated contact member 7, the latter being substantially the same in construction and operation as the contact member 7 shown in Figs. 1 and 2.
- the operating-lever S having a suitable handle 8 is pivotally mounted between the arms or plates 5 and is connected to the arm (5 by means of atoggle-lever, one
- the base-plate or switchboard-panel 1 is shown as provided with three terminal studs 12, 12, and 12 each of which has on the front of the base board or panel a termi nal plate or block 13, having a plane contactsurface paral lel, or substantially parallel,with the face of the switchbeard-panel, this nu mber and general arrangement of stationary terminals being necessary in all double-throw switches.
- the supportirig-frame 1-1- for the switch-operating mechanism is supported by the middle terminal block 13 or directly by the base-plate 1, and pivotally mounted in this frame is a bifurcated operating-lever 15, provided with a suitable handle 10.
- a bifurcated arm 17 that extends between the arms of the operating-lever 15 nearly to the point at which the handle is applied.
- This arm 1.7 supports the laminated contact member 18, which is substantially the same in construction as the corresponding member shown in the preceding figures of the drawings.
- the supportingarm 17 has an enlarged outer end provided with a curved slot 17, the curvature of which corresponds to the arc of a circle having the pivotal axis of this arm and the operatinglever as a center.
- Pivotally mounted in the outer end of the supporting-arm 17 isalocking-head 19, having two projections 20 and i provided with an opening 21 of clover-lca'li' shape, the recesses of which are marked, respectively, 21, 21 and 21".
- the operatinglever 15 is provided with a pin 22, which extends through this clover-leaf-shaped opening 21 in the locking-head 19, and also through the slot 17 in the supporting-arm 17.
- the supporting-arm 17 is connected to a lug on the outer face of the lockinghead 1.) by means of a coiled sprin 23, and a similar spring 21 connects the supporting-arm with a point on the member 18 located between its pivotal support and the base 1.
- a pair of standards 25 between the outer ends of which is a pin or roller 26 in such position as to be enaged byone oi the projecting arms 20 of the locking-head 19.
- the supporting-frame 14; for the operating mechanism is provided at each side with two arms 27, having inwardly-bent ends 28, so that as the contact member 18 is thrown from one side to the other these ends 28 will serve as guides to prevent any tilting of the brush contact into an inoperative position.
- Aswitch for electric circuits comprising stationary terminals having contact blocks or plates the contact-faces of which are in sub stantially the same plane, a supporting-base therefor, a laminated member having beveled ends for engagement with the faces of said terminals, a supporting-arm pivoted at one end to the base and attached to the laminated member at substantially the middle point of the latter and at a considerable distance from the axis of movement of said arm, and an actuating-lever pivoted to the base and having a movable connection with the supportingarm.
- a double-throw switch for electric circuits the combination with a base having three contact-terminals, of an arm pivoted at one end to said base, a double-ended laminated contact member pivoted to said arm, a pivoted operating-lever and means for automatically locking the switch when the operating lever is moved in either direction to its extreme position.
- a double-throw switch for electric circuits, the combination with a base having three contact-terminals, of an arm and an op crating-lever pivoted to the base and having a lost-motion connection with each other, a double-ended laminated contact member and a locking-head pivoted to said arm, and means carried by the operating-lever for moving the loekin ghead into locking position as said operating-lever reaches either of its extreme positions.
- a double-throw switch for electric circuits, the combination with a suitable base provided with middle and end terminals, of a laminated, double-ended contact member, a supporting-arm to which said contact member is pivoted and an operating-lever having the same pivotal axis as said arm and a lostmotion connection therewith, a locking-head pivoted to said arm, and means carried by the operating-lever for throwing said head into locking position, as the contact member reaches each of its circuit-closing positions.
- a do uble-throw switch for electric circuits, the combination with a base having middle and end terminals, of a double-end laminated contact member, an operating-lever, a supporting-arm connecting said contact member with said base and with said lever, a locking device supported by said arm and operated by said lever, as the laminated con tact member reaches either circuit-closing position, and guides for the movable contact member as it moves from the one to the other of its contact-making positions.
Landscapes
- Switch Cases, Indication, And Locking (AREA)
Description
N0. 633,77l. I Patented Sept. 26, I899. G. WRIGHT & C. AALBURG.
SWITCH FOR ELECTRIC CIRCUITS.
(Application filed Jan. 30, 1899.)
(No MotIeL) 3 Sheets8heet IV/T/VESSES" /A/II//V7 OES saw N0. 633,77l. v Patented Sept. 26, I899. G.- WRIGHT & C. AALBURG. SWITCH FOR ELECTRIC CIRCUITS.
(Application filed Jan. 30, 1899.! (No Model.) 3 SheetsSl1eet 2.
W/ TNE SSE S /NVE/V7'0HS w, fggznqu vinw-v THE Noams r-Frzns coy. FHQTO-L|Tr1u., WASHINGTON u c No. 633,77I. Pate nted Sept. 26, I899. G. WRIGHT & C. AALBCRC.
SWITCH FOR ELECTRIC CIRCUITS.
(Application filed Jan. 80, 1889.) (No ModeI.) 3 Sheets-Sheet 3.
/ N VE N T0195 2? ATTORNEY,
THE scams FETERQ c0.. PHOTDLITHQ. WkSHINGTON, o. c.
UNITED STATES PATENT OEEicE.
GILBERT VRIGHT AND CHRISTIAN AALBORG, OF \VILKINSBURG, PENNSYL- VANIA, ASSIGNORS TO THE \VESTINGHOUSE ELECTRIC AND MANUFAC- TURING COMPANY, OF PENNSYLVANIA.
SWlTCH FOR ELECTRIC CIRCUITS.
SPECIFICATION forming part of Letters Patent No. 633,771, dated September 26, 1899.
Application filed January 80,1899. Serial No. 708,783. (No model.)
To all whom it III/(01] OOIMJUIIL:
Be it known that we, GILBERT \VRIGHT, a citizen of the United States, and CHRISTIAN AALBORG, a subject of the King of Sweden 5 and Norway, residing in W'illrinsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Switches for Electric Circuits, (Case No. 801,) of which the following is a specifi- IO cation.
Our invention relates to switches for electric circuits; and it has for its object to provide a switch of such construction that its movable contact member may be readily [5 brought into operative position, locked in such position, and released and separated from its stationary member by an expenditure of power that shall be substantially independent of the current-carrying capacity of the switch and much less than that exercised in opening and closing switches of the types heretofore employed.
Manually-operated switches heretofore in use have generally been of knife-blade and jaw construction, the structures being variously modified in order to increase the current-carrying capacity and facilitate the opening and closing of those of large size. The opening and closing of knife-and-jaw switches 0 having large current-carrying capacity can be eifected, however, only by the application of a considerable amount of power by reason of the fact that the jaws must contain so much material that they will yield to only a very lim- 5 ited degree. We are enabled by our invention to entirely dispense with gripping engagement between the contact-terminals of the switch, and thereby obviate deterioration by reason of frictional wear.
While our invention is suitable for use in connection withcircuits carrying any quantity of current and any degree of electrometive force, it is especially adapted for circuits carrying heavy currents, since it insures a 5 nearly perfect contact between the cooperating terminals, and thus permits of the em ployment of a less amount of copper than is necessary in other types of switches having the same current-carrying capacity.
In the accompanying drawings, Figure 1 is a side elevation of one form of switch constructed in accordance with our invention, and Fig. 2 is a front elevation of the same on a smaller scale. Fig. 3 is a side elevation of a switch having a modified form of operating and locking mechanism, and Fig. i is a front elevation of the same on a smaller scale. Fig.
5 is a side elevation of a double-throw switch constructed in accordance with our invention, and Fig. 6 is a front elevation of the same. Fig. 7 is a detail view of the locking-head forming part of the switch mechanism shown in Figs. 5 and (5.
Referring now particularly to Fig. l l is a supporting-base, which will ordinarily be a switchboard-panel of marble, slate, or other similar material.
2 and 3 are terminal studs which extend through the base-plate l and are respectively provided on the face of the latter with contact plates or blocks i and f, having flat eontact-surfaces parallel with the face of said base-plate.
Attached to the terminal block i or to the base 1 adjacent to said terminal block are two forwardly-projecting plates 5, to the outer or lower end of each of which is pivoted an arm 6, the other ends of said arms being bolted or otherwise rigidly fastened to the movable contact member7ol'the switch. This movable contact member '7 is built up of thin plates bolted or riveted together at or near their middle portions and terminating at each end in a plane that is substantially parallel to the faces of the terminal blocks or plates i and 4; when said member is brought nearly to its circuit-closing position. An operating arm or lever 8, provided with a suitable handle 8, is formed with two curved arms, the ends of which are respectively pivoted to the plates 5 at points materially nearer to the middle of the brush-contact member '7 than the pivotal points of the arms 6. A toggle-lever arm 9 is hinged or pivoted at one end to the lever S and at its other end to the arms (3, at such 5 points that when the switch is in its closed position the axis of the pivotal connection with the arms (3 will be slightly below a straight line joining the pivotal axis of the lever S and that between the 1everarm.)and 10o said lever 8. The contact member 7 is pro vided with a lug or projection and the opcrating-lever 8 with asimilar lug 11, this being so located and of such dimensions that they will come into engagement when the movable member of the switch has been moved to its locked position.
It will be seen from the foregoing descrip tion that the toggle-lever operating mechanism for the movable member of the switch is such that the switch may be very easily opened and closed irrespective of its size and carrying capacity and that when closed it will be locked and firmly held in that position by reason of the toggle-joint between the movable contact member and its operatinglever having passed slightly beyond the deadcenter.
Referring now to Figs. 3 and 4, the base plate or slab 1, the terminal studs 2 and 3, and their contact blocks or plates a and a are or may be the same in construction and arrangement as the corresponding parts shown in Figs. 1 and 2. The plates 5", constituting, the supporting-frame for the toggle-lever mechanism, perform the same function as the parts 5 shown in Figs. 1 and 2; but on account of differences in the structure and arrangement of the toggle-lever mechanism these parts are shown in Figs. 3 and 4: as of different form. The supporting-arm 6 is pivotally mounted at one end between the plates 5 and is attached at its other end to the lam inated contact member 7, the latter being substantially the same in construction and operation as the contact member 7 shown in Figs. 1 and 2. The operating-lever S, having a suitable handle 8 is pivotally mounted between the arms or plates 5 and is connected to the arm (5 by means of atoggle-lever, one
arm 9 of which is pivoted to the arm (3 at such a point that when the operating lever and handle have been moved to the position shown in Fig. 3 of the drawings-that is, to such a point that the-desired engagement between the laminated contact member and the stationary terminals has been effected the toggle-joint between the two arms of the lever will be slightly above a straight line joining the pivotal axis of the lever 8 and the axis of the pivot joining the lever-arm 9 with the arm (5. It will be readily seen from this construction that the movable member of the switch is easily moved toward and away from the stationary terminals and that when moved to the closed position it will be securely locked.
lVhile we have shown two combinations of devices for operating and looking a single throw brush-contact switch, we do not desire to limit our invention to these specific forms, since other modifications and variations may obviously be made by one skilled in the art without changing the substantial mode of operation or result and without departing from the spirit and scope of the invention.
Referring now particularly to Figs. 5, 6,
and 7, the base-plate or switchboard-panel 1 is shown as provided with three terminal studs 12, 12, and 12 each of which has on the front of the base board or panel a termi nal plate or block 13, having a plane contactsurface paral lel, or substantially parallel,with the face of the switchbeard-panel, this nu mber and general arrangement of stationary terminals being necessary in all double-throw switches. The supportirig-frame 1-1- for the switch-operating mechanism is supported by the middle terminal block 13 or directly by the base-plate 1, and pivotally mounted in this frame is a bifurcated operating-lever 15, provided with a suitable handle 10. Mounted upon the same shafts or pivots is a bifurcated arm 17, that extends between the arms of the operating-lever 15 nearly to the point at which the handle is applied. This arm 1.7 supports the laminated contact member 18, which is substantially the same in construction as the corresponding member shown in the preceding figures of the drawings. The supportingarm 17 has an enlarged outer end provided with a curved slot 17, the curvature of which corresponds to the arc of a circle having the pivotal axis of this arm and the operatinglever as a center. Pivotally mounted in the outer end of the supporting-arm 17 isalocking-head 19, having two projections 20 and i provided with an opening 21 of clover-lca'li' shape, the recesses of which are marked, respectively, 21, 21 and 21". The operatinglever 15 is provided with a pin 22, which extends through this clover-leaf-shaped opening 21 in the locking-head 19, and also through the slot 17 in the supporting-arm 17. The supporting-arm 17 is connected to a lug on the outer face of the lockinghead 1.) by means of a coiled sprin 23, and a similar spring 21 connects the supporting-arm with a point on the member 18 located between its pivotal support and the base 1. At each end of the supporting-base 1 is a pair of standards 25, between the outer ends of which is a pin or roller 26 in such position as to be enaged byone oi the projecting arms 20 of the locking-head 19.
The supporting-frame 14; for the operating mechanism is provided at each side with two arms 27, having inwardly-bent ends 28, so that as the contact member 18 is thrown from one side to the other these ends 28 will serve as guides to prevent any tilting of the brush contact into an inoperative position.
The operation of the invention will now be described more fully, it being assumed that the parts are in the positions indicated in Figs. 5 and 6 and that it is desired to change the circuit connections from terminals 12 and 12 to terminals 12 and 12. The
operator grasps the handle 16 and draws it outward, and by so doing first moves the pin 22 to such a point that the spring 23 will move the locking-head to throw the recess 21 into engagement with the pin, thus releasing the supporting-arm 17 and switch-contact member 18. As the operating-lever and handle are moved farther outward the pin 22 will move in the curved slot 17 until it reaches its outer end,when the supporting-arm willbe engaged by pin 22 and moved with the operatin glever. As the supporting-arm begins to move the spring 24 will rock the member 18 on its pivot and hold it in such position that its forward movement cannot be interfered with by the ends 28 of the upper guide-arms 27. As the movement of the lever 15 and arm 17 is continued through an arc of one hundred and eighty degrees the contact member 18 will be carried over to a position in front of the terminal blocks or plates 12 and 12. It will be prevented from turning into an inoperative position during this movement by the inturned ends 28 of the lower guide-arms 27.
-As the contact member 18 is moved into operative engagement with the terminal-blocks ,the pin 22 will move into the recess 21 of the opening 21 in thelocking-head, and thus rock the head on its pivot in opposition to the pull of the spring 23, so as to bring arms 20 underneath the pin 26, and thus lock the switch in its new position.
While we have found the construction and arrangement of parts herein shown and described to be useful and effective in operation, we do not desire to limit ourselves to the specific details disclosed, since these may be modified without departing from the invention.
e claim as our invention 1. Aswitch for electric circuits comprising stationary terminals having contact blocks or plates the contact-faces of which are in sub stantially the same plane, a supporting-base therefor, a laminated member having beveled ends for engagement with the faces of said terminals, a supporting-arm pivoted at one end to the base and attached to the laminated member at substantially the middle point of the latter and at a considerable distance from the axis of movement of said arm, and an actuating-lever pivoted to the base and having a movable connection with the supportingarm.
2. Ina switch for electric circuits, the com bination with a base having stationary contact-terminals, of a laminated contact member having beveled ends adapted to engage the plane faces of said contact-terminals, a supporting-arm pivoted at one end to the base and attached to the laminated member at substantially the middle point of said member, and an actuating-lever having operative connections with the base and with the supporting-arm for the laminated member.
In a double-throw switch for electric circuits the combination with a base having three contact-terminals, of an arm pivoted at one end to said base, a double-ended laminated contact member pivoted to said arm, a pivoted operating-lever and means for automatically locking the switch when the operating lever is moved in either direction to its extreme position.
4:. In a double-throw switch for electric circuits, the combination with a base having three contact-terminals, of an arm and an op crating-lever pivoted to the base and having a lost-motion connection with each other, a double-ended laminated contact member and a locking-head pivoted to said arm, and means carried by the operating-lever for moving the loekin ghead into locking position as said operating-lever reaches either of its extreme positions.
5. In a double-throw switch for electric circuits, the combination with a suitable base provided with middle and end terminals, of a laminated, double-ended contact member, a supporting-arm to which said contact member is pivoted and an operating-lever having the same pivotal axis as said arm and a lostmotion connection therewith, a locking-head pivoted to said arm, and means carried by the operating-lever for throwing said head into locking position, as the contact member reaches each of its circuit-closing positions.
(3. In a double-throw switch for electric circuits, the combination with a base having middle and end terminals, of a double-end. laminated contact member, an operating-lever, a supportingarm connecting said contact member with said base and with said op crating-lever, a locking device supported by said arm and operated by said lever, as the laminated contact member reaches eithercircuit-closin g position.
7. In a do uble-throw switch for electric circuits, the combination with a base having middle and end terminals, of a double-end laminated contact member, an operating-lever, a supporting-arm connecting said contact member with said base and with said lever, a locking device supported by said arm and operated by said lever, as the laminated con tact member reaches either circuit-closing position, and guides for the movable contact member as it moves from the one to the other of its contact-making positions.
In testimony whereof we have hereunto subscribed our names this 25th day of January, 1899.
GILBERT WRIGHT. OHRISTIAN AALBORG.
\Vitnesses:
WESLEY G. CARR, 11. C. TENER.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US70378399A US633771A (en) | 1899-01-30 | 1899-01-30 | Switch for electric circuits. |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US70378399A US633771A (en) | 1899-01-30 | 1899-01-30 | Switch for electric circuits. |
Publications (1)
Publication Number | Publication Date |
---|---|
US633771A true US633771A (en) | 1899-09-26 |
Family
ID=2702363
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US70378399A Expired - Lifetime US633771A (en) | 1899-01-30 | 1899-01-30 | Switch for electric circuits. |
Country Status (1)
Country | Link |
---|---|
US (1) | US633771A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2513649A (en) * | 1946-04-30 | 1950-07-04 | Ite Circuit Breaker Ltd | Clamp tight switch |
US2547153A (en) * | 1946-08-21 | 1951-04-03 | Ite Circuit Breaker Ltd | Double-throw clamping switch |
US2553238A (en) * | 1946-05-21 | 1951-05-15 | Ite Circuit Breaker Ltd | Double throw clamp-tight switch |
-
1899
- 1899-01-30 US US70378399A patent/US633771A/en not_active Expired - Lifetime
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2513649A (en) * | 1946-04-30 | 1950-07-04 | Ite Circuit Breaker Ltd | Clamp tight switch |
US2553238A (en) * | 1946-05-21 | 1951-05-15 | Ite Circuit Breaker Ltd | Double throw clamp-tight switch |
US2547153A (en) * | 1946-08-21 | 1951-04-03 | Ite Circuit Breaker Ltd | Double-throw clamping switch |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US819360A (en) | Electrical switch. | |
US2227160A (en) | Electric switch | |
US633771A (en) | Switch for electric circuits. | |
GB1174364A (en) | Interlock Structure for Two Manually Operable Toggle Switches. | |
US2103792A (en) | Control switch | |
US2234563A (en) | Circuit controlling device | |
US659946A (en) | Electric switch. | |
US2479266A (en) | Quick make and break switch | |
US3646299A (en) | Pole mechanism for double-throw pressure contact switch | |
US691766A (en) | Electric switch. | |
US2018958A (en) | Device for controlling electric circuits | |
US1379691A (en) | Controller | |
US771989A (en) | Electric switch. | |
US2095796A (en) | Switch | |
US570418A (en) | wurts | |
US1115448A (en) | Circuit-breaker. | |
US2784602A (en) | Snap action operating mechanism for switches | |
US2617903A (en) | Electric switch | |
US1559104A (en) | Switch-operating mechanism | |
US2599242A (en) | Rotary circuit interrupter | |
US1527725A (en) | Switching mechanism | |
US682818A (en) | Switch for electromotors. | |
US599954A (en) | Gilbert wright | |
US615347A (en) | Island | |
US1702463A (en) | Rear-of-panel knife-blade switch |