US1653313A - Distributing switch - Google Patents

Distributing switch Download PDF

Info

Publication number
US1653313A
US1653313A US684577A US68457724A US1653313A US 1653313 A US1653313 A US 1653313A US 684577 A US684577 A US 684577A US 68457724 A US68457724 A US 68457724A US 1653313 A US1653313 A US 1653313A
Authority
US
United States
Prior art keywords
contact
fingers
lingers
plate
insulated
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
Application number
US684577A
Inventor
Sanner Hulbert
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
LOTHAR EDERER
Original Assignee
LOTHAR EDERER
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority to DEE30753D priority Critical patent/DE423718C/en
Application filed by LOTHAR EDERER filed Critical LOTHAR EDERER
Priority to US684577A priority patent/US1653313A/en
Application granted granted Critical
Publication of US1653313A publication Critical patent/US1653313A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H19/00Switches 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
    • H01H19/54Switches 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
    • H01H19/56Angularly-movable actuating part carrying contacts, e.g. drum switch
    • H01H19/58Angularly-movable actuating part carrying contacts, e.g. drum switch having only axial contact pressure, e.g. disc switch, wafer switch

Definitions

  • My invention relates to improvements in distributing switches and circuit selectors and has for one object to provide a new and improved form of distributing switch and :3 circuit selectors associated therewith whereby a switch operated by clockwork, electric or otherwise may be used to close selected circuits through selector device.
  • Another object oi my invention is to provide a new 0 and improved form of switch and selector mechanism which will be light compact and easily manufactured.
  • Another object is to associate a switch and a selector in a compact, easily assembled but conveniently separable unit. Other objects will appear from time to time in the specification and claims.
  • Figure 2 is a section along the line 2-2 of Figure 1;
  • Figures 3 and i are perspective views of contact fingers
  • Figure 5 is a section along the line 55 of Figures 3 and 4t;
  • Figure 6 is a blank from which the con tact fingers are formed
  • Figure 7 is a plan View of a modified form with parts removed
  • Figure 8 is a section along the line 8-8- of Figure 7 with the contact arms in position';
  • Figure 9 is a blank on an enlarged scale from which the contact fingers shown in Figures 7 and 8 are formed;
  • Figure 10 is a perspective view of one of the contact fingers
  • Figure 11 is a sectimi along the line 11l-1l of Figure 10;
  • Figure 12 is 2 section along the line lit-12 oi Figure 10.
  • h A is an insulating supporting panel. It is provided with a series of concentric spaced perforations A A. These perforations contain the cylindrical tubular shanks A A of U-shaped contact bars A, A some of which are notched at two points on their sides at A All the shanks for these contact bars are of the same diameter but the shanks A? are longer than the shanks A ⁇ the the 5, 1924. Serial No. 684,577.
  • A is an annular insulating plate which overlies the lower arm of the U of each of the bars A. This plate is apertured in line with the perforations A so that the shanks A may pass through.
  • A. is a second insulating plate which overlies the under arm of the U, A.
  • B, B are annular supporting rings arranged above and below the banks of con tact fingers. They are insulated from the contact fingers by insulating rings'B and there is associated with each contact finger a contact ring B insulated from it by an insulating ring B This entire assembly is held together by bolts B which pass through the notches betweenadjacent pairs of contact fingers A.
  • a sleeve B carries the tension on the bolt and holds the parts together as a unit.
  • B is a spider mounted on these bolts and having a central operating hub B B is a clock shaft rotatable in the base A at one end and extending out through the hub B
  • This clock shaft carries rotatable thereon a sleeve 13, which sleeve rotates in the bearing B C is a bifurcated spring contact finger mounted on the shaft B and insulated therefrom.
  • the width of the contact finger is substantially equal to the width of any one of the terminals or contact bars and as this finger rotates with the shaft 13", it maintains constant contact with the contact ring B and the contact fingers A and closes a circuit between them.
  • C is a similar bifurcated contact finger mounted on the sleeve B which operates in the same way, the idea being; that the shaft B and the sleeve B? will be given an hour and minute motions The upper bank will represent the minutes and there will be sixty lingers in that bank,
  • the lower bank will represent hours, there 7 being twenty-fourin that, but the hour and minute arrangement might be reversed or a decimal system or any other system might be used.
  • the contact ring B has associated with it iii 'ripherally arranged conductor bars E".
  • tact fingers A are made from the blank D the lower enlarged portion D being rolled to form the shank A, the long other portion being bent along the lines D 1) to the shape indicated in Figure 3.
  • the contact fingers A shown in Figure it are made in the same manner from similar blanks but of different proportions.
  • a selector which comprises an end plate E, alternate conductor plates E and insulator plates E a central holding bar E and a. series of pe- The conductor plates E" are peripherally notched, there being a bar E in line with rach notch in each plate, he notches being arranged in line so that the spring contact lingers E may be positioned along the bar 19 and thrust. it into the notch in any one of the insulating; plates.
  • Ii lating tubes E pass through perforations in the plates and contain conductors E there being one conductor for each plate and such conductor terminating at the plate and being altogether out of. contact with the others.
  • the wires D may lead to a bell ringing apparatus or anything ot that kind and it is possible to select the time at which the bell will ring by positioning the spring linger
  • the bifurcated contact switches will go round and round but nothing will happen until such time as the two lingers engage the two contact lingers associated in a circuit which had been selected by the spring on the. conductor E when a circuit will be closed and a bell will ring or other signal will operate.
  • the contact linger-s are made 'l'roni ljilanks having a narrow end linger torin-- lugportion Q, a wider tube torrning portion Q9. and laterally ezttmding wing portions (3f, bent to torn; the tube Q ⁇ linger and U-shaped member Q".
  • These contact lingers are located in two concentric groups of holes in the supporting plate Q. the U-shaped' portion Qf engaging slots Q, so that the lingers are always radially positioned.
  • the lingers of the inner group Q are shorter than the fingers (i These lingers are adapted to be engaged by splitspring contact arms R, R mounted respectively on the timing shaft R and sleeve and insulated from it by insulating sleeves Contact slip rings R are associated with each of these fingers and adapted to be engaged by wipers R and R on the binding posts R R" and associated with conductors R R whereby the circuits may be closed.
  • the relation between the selector elements and the lingers is the same in this case as in the preferred form.
  • a contact bank comprising a plurality of U-shaped contact fingers, flat supporting pl ates arranged on opposed sides of the contact arm of the. U, means for holding the plate in position and for holding the contactlingers and the plates as a unit in position.
  • An electric distributor comprising an annularly arranged group ot contact lingers. a contact ring insulated from and arranged adjacent said fingers and a wiper adapted to travel along the contact lingers and selectively close a circuit between one linger ot the group and the ring.
  • the fingers being U shaped. and having each a hollow cylindrical shank associated with the arm of the U which is not adapted to be engaged by the wiper.
  • An electric distriluilor compriing an annularly arranged group of contact lingers. a contact ring insulated 'troin rnd arranged atljzurcnt said lingers and a wiper adapted to travel along the contact lingers and sclertirely close a circuit bctwemi one linger ot the group and the ring, the lingers being U-shapcd and having each a hollow cylindrical shank associated with the arm of the U which is not adapted to be engaged by the wiper, conductors adapted to remoral'ily engage each one of the shanks and a con doctor in permanent engagement with the contact ring.
  • An electric distributor comprising an annularly arranged group of contact fingers, an insulated supporting base for the group, there being a hollow tubular conductor shank associated with each linger of the group and. a wiper adapted to engage successively tinpro gers at a point removed from the shank, a selective conductor adapted to be removably engaged with the shank.
  • a contact bank comprising an insulated base, a plurality of groups of contact fingers, tubular shanks associated one with each finger penetrating the supporting base, insulating plates adapted to hold the shanks and fingers in position with the fingers themselves radially disposed about a common center on the bar e, the insulating plates separating the fingers in two separate insulated concentric groups.
  • a circuit selecting device comprising in combination a selecting switch system including wipers and contact fingers, a man-.
  • ually adjusted selecting system adapted to be removably arranged with the switch system and means associated with the manually adjusted system for selecting individual circuits -lior operation.
  • circuit selecting device comprising a plurality of insulated plates arranged side by side, a plurality of separate conductor bars arranged adjacent the peripheries of said bars and means interposed between the bar and the plate to close a circuit between them, of a switch assembly comprising a plurality of contact fingers, there being an electric connection between one contact finger and each bar and plate and wipers adapted to be moved across the fingers to close circuits to the bars and plates.
  • circuit select ing device comprising a plurality of insulated plates arranged side by side, a pluralityot separate conductor bars and means interposed between the bar and the plate to close a circuit between them, of a switch assembly comprising a plurality of contact lingers, there being an electric connection between one contact finger and each bar and plate and wipers adapted to be moved across the fingers to close circuits to the bars and plates, the circuit selecting device being removably associated with the switch assembly.
  • circuit selecting device com 'irising a plurality of insulated plates arranged side by side, a plurality of separate conductor bars and means interposed between the bar and the plate to close a circuit between them, of a switch a sembly comprising a plurality of contact fingers, there being an electric connection between one contact finger and each bar and plate and wipers adapted to be moved across the fingers to close circuits to the bars and plates, the circuit selecting device being removably associated with the switch assembly, the switch fingers having hollow tubular shank s adapted to be yieldingly engaged by the conductor bars and there being conductor pins projecting one from each plate to engage other such tubular shanks.
  • a contact finger comprising a tubular shank open at both ends only, integral therewith a- U-shaped extension having two arms tangential to the shank, a fiat supporting strip projecting upwardly beyond the U in line with. one side of the shank and a contact end integral with and bent at right angles to the supporting element.
  • an apertured supporting base there being slots in the face thereof in line with the apertures, contact fingers having tubular shanks adapted to penetrate the apertures in the base and extensions adapted to engage the'grooves in the base, and contact fingers extending upwardly from the shanks and bent at right angles to the axis thereof.
  • An electric distributor comprising an annularly arranged group of contact fingers, an insulated plate engaging them, a continuous conductor ring on the opposed side of the plate immediately adjacent the fingers having substantially the same inside diam eter as the inside diameter of the group of fingers, a wiper adapted to travel along the fingers and ring. comprising abifurcated member, one fork of which is in constant engagement with the ring, the other fork, of which is in engagen'lent with the fingers.

Description

Dec; 20, 1927. 1,653,313
. Y H. SANNER DISTRIBUTING SWITCH Filed J 5, 1924 2 SPeets-Sheec 1 6 A lfl c g 2 .2
, v7 fnvenzor. fluZZert fianzzer Dec. .20, 192?. 1,653,313
H. SANNER DISTRIBUTING SWITCH I Filed Jan.5, 1924 2 Sheen-"Sheet 2 Patented lies. 2%, i927.
onirsn sir.
TES
res ns HULBERT SANNEB, OF CHICAGO, ILLINOIS, i'sSSIG-NGR T LQTHAR EDERER, OF CHICrhGG, ILLINOIS.
DISTRIBUTING SWITCH.
Application filed January My invention relates to improvements in distributing switches and circuit selectors and has for one object to provide a new and improved form of distributing switch and :3 circuit selectors associated therewith whereby a switch operated by clockwork, electric or otherwise may be used to close selected circuits through selector device. Another object oi my invention is to provide a new 0 and improved form of switch and selector mechanism which will be light compact and easily manufactured. Another object is to associate a switch and a selector in a compact, easily assembled but conveniently separable unit. Other objects will appear from time to time in the specification and claims.
My invention is illustrated more or less diagrammatically in the accompanying drawings, wherein- Figure 1 is a plan view with parts removed and parts in section;
Figure 2 is a section along the line 2-2 of Figure 1;
Figures 3 and i are perspective views of contact fingers;
Figure 5 is a section along the line 55 of Figures 3 and 4t;
Figure 6 is a blank from which the con tact fingers are formed;
Figure 7 is a plan View of a modified form with parts removed;
Figure 8 is a section along the line 8-8- of Figure 7 with the contact arms in position';
Figure 9 is a blank on an enlarged scale from which the contact fingers shown in Figures 7 and 8 are formed;
Figure 10 is a perspective view of one of the contact fingers; e
Figure 11 is a sectimi along the line 11l-1l of Figure 10;
Figure 12 is 2 section along the line lit-12 oi Figure 10.
Like parts are indicated by like characters "throughout the drawings and specification. h A is an insulating supporting panel. It is provided with a series of concentric spaced perforations A A These perforations contain the cylindrical tubular shanks A A of U-shaped contact bars A, A some of which are notched at two points on their sides at A All the shanks for these contact bars are of the same diameter but the shanks A? are longer than the shanks A} the the 5, 1924. Serial No. 684,577.
tance between the two arms of the U is greater in thecontact bars A than in A. A is an annular insulating plate which overlies the lower arm of the U of each of the bars A. This plate is apertured in line with the perforations A so that the shanks A may pass through. A. is a second insulating plate which overlies the under arm of the U, A. These contact bars or fingers are all of them arranged radially out of contact with one another and the two banks are insulated and held in place by the two annular insulating discs.
B, B are annular supporting rings arranged above and below the banks of con tact fingers. They are insulated from the contact fingers by insulating rings'B and there is associated with each contact finger a contact ring B insulated from it by an insulating ring B This entire assembly is held together by bolts B which pass through the notches betweenadjacent pairs of contact fingers A. A sleeve B carries the tension on the bolt and holds the parts together as a unit. B is a spider mounted on these bolts and having a central operating hub B B is a clock shaft rotatable in the base A at one end and extending out through the hub B This clock shaft carries rotatable thereon a sleeve 13, which sleeve rotates in the bearing B C is a bifurcated spring contact finger mounted on the shaft B and insulated therefrom. The width of the contact finger is substantially equal to the width of any one of the terminals or contact bars and as this finger rotates with the shaft 13", it maintains constant contact with the contact ring B and the contact fingers A and closes a circuit between them. C is a similar bifurcated contact finger mounted on the sleeve B which operates in the same way, the idea being; that the shaft B and the sleeve B? will be given an hour and minute motions The upper bank will represent the minutes and there will be sixty lingers in that bank,
the lower bank will represent hours, there 7 being twenty-fourin that, but the hour and minute arrangement might be reversed or a decimal system or any other system might be used.
The contact ring B has associated with it iii 'ripherally arranged conductor bars E".
tact fingers A are made from the blank D the lower enlarged portion D being rolled to form the shank A, the long other portion being bent along the lines D 1) to the shape indicated in Figure 3. The contact fingers A shown in Figure it are made in the same manner from similar blanks but of different proportions.
Associated with this device is a selector which comprises an end plate E, alternate conductor plates E and insulator plates E a central holding bar E and a. series of pe- The conductor plates E" are peripherally notched, there being a bar E in line with rach notch in each plate, he notches being arranged in line so that the spring contact lingers E may be positioned along the bar 19 and thrust. it into the notch in any one of the insulating; plates. Ii lating tubes E pass through perforations in the plates and contain conductors E there being one conductor for each plate and such conductor terminating at the plate and being altogether out of. contact with the others. The result of this arrangement is that there are conductors E and E arranged in concentric rings projectingbeyond the plate. When the projection is positioned by the bar E and by the unequally spaced concentric pins E arranged to insure proper angular relation, each of the conductors E and E engages one ol? the shanks A. A" to close a circuit between a plate and two .ot the pairs of conductor lingers subiect to the sleeve closure made by the spring linger. The wires D may lead to a bell ringing apparatus or anything ot that kind and it is possible to select the time at which the bell will ring by positioning the spring linger The bifurcated contact switches will go round and round but nothing will happen until such time as the two lingers engage the two contact lingers associated in a circuit which had been selected by the spring on the. conductor E when a circuit will be closed and a bell will ring or other signal will operate.
In the n'ioditietl term shown in l igures T to 12 ii'iclusive, the contact linger-s are made 'l'roni ljilanks having a narrow end linger torin-- lugportion Q, a wider tube torrning portion Q9. and laterally ezttmding wing portions (3f, bent to torn; the tube Q} linger and U-shaped member Q". These contact lingers are located in two concentric groups of holes in the supporting plate Q. the U-shaped' portion Qf engaging slots Q, so that the lingers are always radially positioned. The lingers of the inner group Q are shorter than the fingers (i These lingers are adapted to be engaged by splitspring contact arms R, R mounted respectively on the timing shaft R and sleeve and insulated from it by insulating sleeves Contact slip rings R are associated with each of these fingers and adapted to be engaged by wipers R and R on the binding posts R R" and associated with conductors R R whereby the circuits may be closed. The relation between the selector elements and the lingers is the same in this case as in the preferred form.
It will be evident that while I have shown in my drawings an operative device, still many changes might be made in the size, shape and disposition of parts without departing materially from the spirit of my invention and I wish therefore. that my showing be taken as in a sense diagrammatic.
I claim:
1. A contact linger connprising, a flat U- shaped body and an integral hollow sleeve perpendicular to one arm oil the U.
2. A contact bank comprising a plurality of U-shaped contact fingers, flat supporting pl ates arranged on opposed sides of the contact arm of the. U, means for holding the plate in position and for holding the contactlingers and the plates as a unit in position.
A contact bank con'iprising a plurality oi? U-shaped contact lingers. 'l'lat supporting plates arranged on opposed sides oi" the contact lingers of the U, means for holding the plate in position and for holding the core tact lingers and the plates as a unit in position, and a plurality of separate short contact lingers, one associated with but insulated from each of the U-shaped lingers.
t. An electric distributor comprising an annularly arranged group ot contact lingers. a contact ring insulated from and arranged adjacent said fingers and a wiper adapted to travel along the contact lingers and selectively close a circuit between one linger ot the group and the ring. the fingers being U shaped. and having each a hollow cylindrical shank associated with the arm of the U which is not adapted to be engaged by the wiper.
5. An electric distriluilor compri ing an annularly arranged group of contact lingers. a contact ring insulated 'troin rnd arranged atljzurcnt said lingers and a wiper adapted to travel along the contact lingers and sclertirely close a circuit bctwemi one linger ot the group and the ring, the lingers being U-shapcd and having each a hollow cylindrical shank associated with the arm of the U which is not adapted to be engaged by the wiper, conductors adapted to remoral'ily engage each one of the shanks and a con doctor in permanent engagement with the contact ring.
6. An electric distributor comprising an annularly arranged group of contact fingers, an insulated supporting base for the group, there being a hollow tubular conductor shank associated with each linger of the group and. a wiper adapted to engage successively tinpro gers at a point removed from the shank, a selective conductor adapted to be removably engaged with the shank.
7. A contact bank comprising an insulated base, a plurality of groups of contact fingers, tubular shanks associated one with each finger penetrating the supporting base, insulating plates adapted to hold the shanks and fingers in position with the fingers themselves radially disposed about a common center on the bar e, the insulating plates separating the fingers in two separate insulated concentric groups.-
8. A circuit selecting device comprising in combination a selecting switch system including wipers and contact fingers, a man-.
ually adjusted selecting system adapted to be removably arranged with the switch system and means associated with the manually adjusted system for selecting individual circuits -lior operation.
9. The combination with a circuit selecting device comprising a plurality of insulated plates arranged side by side, a plurality of separate conductor bars arranged adjacent the peripheries of said bars and means interposed between the bar and the plate to close a circuit between them, of a switch assembly comprising a plurality of contact fingers, there being an electric connection between one contact finger and each bar and plate and wipers adapted to be moved across the fingers to close circuits to the bars and plates.
10. The combination with a circuit select ing device comprising a plurality of insulated plates arranged side by side, a pluralityot separate conductor bars and means interposed between the bar and the plate to close a circuit between them, of a switch assembly comprising a plurality of contact lingers, there being an electric connection between one contact finger and each bar and plate and wipers adapted to be moved across the fingers to close circuits to the bars and plates, the circuit selecting device being removably associated with the switch assembly.
'11. The combination with a circuit selecting device com 'irising a plurality of insulated plates arranged side by side, a plurality of separate conductor bars and means interposed between the bar and the plate to close a circuit between them, of a switch a sembly comprising a plurality of contact fingers, there being an electric connection between one contact finger and each bar and plate and wipers adapted to be moved across the fingers to close circuits to the bars and plates, the circuit selecting device being removably associated with the switch assembly, the switch fingers having hollow tubular shank s adapted to be yieldingly engaged by the conductor bars and there being conductor pins projecting one from each plate to engage other such tubular shanks.
12. A contact finger comprising a tubular shank open at both ends only, integral therewith a- U-shaped extension having two arms tangential to the shank, a fiat supporting strip projecting upwardly beyond the U in line with. one side of the shank and a contact end integral with and bent at right angles to the supporting element.
13. In an electric distributo an apertured supporting base, there being slots in the face thereof in line with the apertures, contact fingers having tubular shanks adapted to penetrate the apertures in the base and extensions adapted to engage the grooves in the base.
1.4:. In an electric distributor, an apertured supporting base, there being slots in the face thereof in line with the apertures, contact fingers having tubular shanks adapted to penetrate the apertures in the base and extensions adapted to engage the'grooves in the base, and contact fingers extending upwardly from the shanks and bent at right angles to the axis thereof.
15. An electric distributor comprising an annularly arranged group of contact fingers, an insulated plate engaging them, a continuous conductor ring on the opposed side of the plate immediately adjacent the fingers having substantially the same inside diam eter as the inside diameter of the group of fingers, a wiper adapted to travel along the fingers and ring. comprising abifurcated member, one fork of which is in constant engagement with the ring, the other fork, of which is in engagen'lent with the fingers.
Signed at Chicago, county of Cook and State of Illinois, this th day of December 1923.
HULBERT SANNER.
US684577A 1924-01-05 1924-01-05 Distributing switch Expired - Lifetime US1653313A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
DEE30753D DE423718C (en) 1924-01-05 Electrical switching device
US684577A US1653313A (en) 1924-01-05 1924-01-05 Distributing switch

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US684577A US1653313A (en) 1924-01-05 1924-01-05 Distributing switch

Publications (1)

Publication Number Publication Date
US1653313A true US1653313A (en) 1927-12-20

Family

ID=24748626

Family Applications (1)

Application Number Title Priority Date Filing Date
US684577A Expired - Lifetime US1653313A (en) 1924-01-05 1924-01-05 Distributing switch

Country Status (1)

Country Link
US (1) US1653313A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2468398A (en) * 1943-08-03 1949-04-26 Dana A Griffin Electrical impedance testing bridge
US3248490A (en) * 1963-07-30 1966-04-26 Cts Corp Selector switch with multiple tie rod fastener and mounting bracket
US3310641A (en) * 1964-11-02 1967-03-21 Hamilton Watch Co Rotary switch with improved contact element structure

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2468398A (en) * 1943-08-03 1949-04-26 Dana A Griffin Electrical impedance testing bridge
US3248490A (en) * 1963-07-30 1966-04-26 Cts Corp Selector switch with multiple tie rod fastener and mounting bracket
US3310641A (en) * 1964-11-02 1967-03-21 Hamilton Watch Co Rotary switch with improved contact element structure

Similar Documents

Publication Publication Date Title
US1653313A (en) Distributing switch
US1832869A (en) Electric switch
US2477741A (en) Electrical switch
US1969978A (en) Code setting device for signal systems
US1144870A (en) Code-signal device.
US1913992A (en) Switching device
US1651275A (en) Electric-sign controller
US1237517A (en) Program-clock.
US2036731A (en) Multiple contact selector switch
US1627168A (en) Electrical transmitter
US3500389A (en) Electric coding switches
US2114678A (en) Device for controlling a plurality of luminous tubes
US3122843A (en) Electrical question and answer matching device
US1543824A (en) Switching device
US3030461A (en) Single pole multiple contact switch
US1927440A (en) Switch
US1669434A (en) Switching device
US1076149A (en) Automatic electromagnetic switch.
US1689348A (en) Combined jack and selecting switch
DE429155C (en) Switching device for the light bulbs in the illuminated letters of the electric universal neon sign
US1271600A (en) Electric sign.
US1603093A (en) Electric switch mechanism
US3377446A (en) Timing mechanism
US1945511A (en) Remote control apparatus
US944665A (en) Selective electric signaling apparatus.