US1838020A - Inclosed switch - Google Patents

Inclosed switch Download PDF

Info

Publication number
US1838020A
US1838020A US335250A US33525029A US1838020A US 1838020 A US1838020 A US 1838020A US 335250 A US335250 A US 335250A US 33525029 A US33525029 A US 33525029A US 1838020 A US1838020 A US 1838020A
Authority
US
United States
Prior art keywords
handle
switch
box
crank
bushing
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
US335250A
Inventor
Herman J Hammerly
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.)
Trumbull Electric Manufacturing Co
Original Assignee
Trumbull Electric Manufacturing Co
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
Application filed by Trumbull Electric Manufacturing Co filed Critical Trumbull Electric Manufacturing Co
Priority to US335250A priority Critical patent/US1838020A/en
Application granted granted Critical
Publication of US1838020A publication Critical patent/US1838020A/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
    • H01H21/00Switches operated by an operating part in the form of a pivotable member acted upon directly by a solid body, e.g. by a hand
    • H01H21/02Details
    • H01H21/18Movable parts; Contacts mounted thereon
    • H01H21/36Driving mechanisms
    • H01H21/40Driving mechanisms having snap action
    • H01H21/42Driving mechanisms having snap action produced by compression or extension of coil spring

Definitions

  • Another object is to provide a quick-make and quick-break mechanism in which the operating movement is started manually but in which the quick movement is spring-pressed and entirely out of control of the operator after the spring movement has once been started.
  • Another object is to provide a switch construction having an externahoperating handle and an internal loose-connection quickmake and quick-break means so constructed that the quick-make and quick-break means cannot be cramped or bound by any lateral.
  • Another object' is to provide a quick-make and quick-break switch construction in which the operating handle and its corelated loose connection parts are secured in position by means of a bushing in such a manner that the operating crank may have a 'relatively loose or endwise shucking engagementwith the' bushing since the crank plays no part in the securing of the loose connection parts in position.
  • Another object is to provide a switch con-, struction having an external operating handle operably supported in one wall of the box and having a further interlocking en-. gagement with the wall of the box which makes it practically impossible to injure or type.
  • FIG. 1 1s a perspective'view of an. inclosed switch embodying my invention and showing the parts of the switch inthe closed circult position with the cover open andbroken awa F1g.'2 is a fragmentary transverse sectional view showing the mounting of the handle, operating crank, and quick-make and break mechanism.
  • Fig. 3 is a detail edge view showing one form of connector between the operating 1 Fig.1 7 "is a perspective view showing the bushing and associated parts for supporting the crank, the operating handle and the quickbreak mechanism in one wall of the box
  • the box 10 may be of any suitable type and construction and provided with any suitable form of cover 11 and latch 12.
  • the switch mechanism will usually be mounted upon an insulating base 13 suitably secured in the box.
  • the operating crank 14 is pivotally supported and adapted to be op-' erated manually by an external handle 15 as will hereinafter be understood.
  • the invention is particularly applicableto switches for controlling two or more legs of a circuit and will therefore be provided with v such a number of blades and corelated elements as may be required.
  • Each circuit controlling unit usually consists of a knife blade switch and a protecting fuse of any suitable Inthe form shown I have illustrated three switch units but it will be necessary to describe only one which is typical.
  • the switch jaws 16 and 17 may be of any suitable type for coacting with a switch blade 18. Preferably, this blade is hinged to the jaw. 16 which constitutes a supporting post.
  • Clips such as 19 are provided for the usual carforms a stop for the on position of the" switch blades and is adapted to strike against 'the insulating base13 when the switch is closed so that the shock of the closing move-' ment is taken .up by the various insulating connectors or plates which are more or less resilient and are not subject to fracture.
  • This foot 21 extends down below the switch blade, as shown in Fig. 3, and whenthe circu'it is opened the upper edge of this foot passes by the adjacent edge of the jaws 17 and serves to cut other interrupt any are which may form between the jaw and the switch blade.
  • This foot 21 may be wider or thicker as shown in Fig. 3 so as to overlap both edges of the jaw 17
  • Another modification shown in. Fig. 4 embodies two connector plates 20 and 22, the lower ends of which serve as are interrupters adjacent both edges of the jaw 17.
  • the ends of the operating crank 14 are bent outwardly and supported in the opposite sides of the box.
  • the right hand end 23 has a bearing in the bushing 24.
  • This bushing also supports the oscillating disc 25 and in turn is supported in the opening 26 in the side wall of the box.
  • the washer 27 is supported. on
  • the bushlng 24 is provided with a shoulder 30 forming a bearing'for the disc 25 and a shoulder '31 which constitutes the bearing in the opening 26.
  • the outer portion 32 of the bushing afi'ords support for the washer 27 and the handle.
  • the width of these shoulders 30, 31 and 32 measured in an axial direction is such as to space the disc 25 no matterhow tightly the bushing is riveted over and no matter how the handle is twisted the parts will always be free to operate independently as is necessary in a quickmake and break switch. This is articularly important in. constructions of this character where the box is usually formed of sheet metal and the walls are somewhat flexible.
  • the rod 40 is hinged at 41 to the lug 39 and is guided by the bracket 42 at the other end.
  • the spring 43 on the rod 40 presses at one end against the head of the rod 40 near the pivot 41 and the other end is held; in operative position against the bracket 42 by means of the projecting end 'of the bracket in which position the spring affords compression action for the quickmake and quick-break movement.
  • the spring 43 presses the disc 25 in a clockwise direction as viewed in Fig. 6, so that the lug 39 presses against the arm of the' crank 14 which in turn is passed against the stop or abutment IrOnember 45 secured to theinner wall of the ox.
  • I A strap member 46 may be secured on the outside of the box and rovided with suitable. holes or openings or sealing or locking the handle 15 either in the open circuit or closed circuit position.
  • the slot 35 is enlarged intermediate its ends and preferably at approximately its center at 35' to permit'the entrance-of the large end of the pin or stud 33 but it is obvious that when the in is moved away from the central position y means of the operatquick-break' ing handle, the shoulder 33' on the pin will overlap the edges of the slot and will thus have a locking'engagement with the wall of the box which cannot be disengaged by .any prying movement of the handle.
  • the quick-make and quick-break elements are all secured in position entirely independently of the internal operating crank.
  • crank has its bearing in the hole in the bushing 24 and the other end has its bearing in a hole in a wall oi the.
  • a box, switch mechanism mounted therein and including a switch position and having a recess in which the end of the crank is detachably supported.
  • a box switch mech-' anism mounted therein and including a switch blade, an operating crank, a connector be tween the blade and the crank, quick-break mechanism and an external operating handle, said quick-break mechanism including a disc having a lost motion connection with the handle and a single bushing for supporting the operating crank, the disc and the handle, said bushing having shoulders for supporting it in the box and for supporting said disc and handle.
  • a snap action switch comprising a box having a side wall, a bushing rotatably mounted in said wall, a throwing disc mounted on said bushing inside of said box, an operating handle mounted on said bushing outside of said box and having a lost motion connection with said disc through said box wall, and a switch crank having one end detachably mounted in said bushing and lost motion means of connectionbetween said disc and said crank.
  • crank an operating disc and a handle mounted on said bushing said handle having a pin fastened thereto and movable in-acurved slot in-said box wall, said slot having an en-.
  • a box a switch operating crank supported at one end in the box wall, said wall having a curved slot concentric about the'end of said crank, an operating handle, a pin rigidly secured to said handle, said pin having shoulders of difierent diameters, one of which movesfreely in the slot, in the box wall and another shoulder being sufficiently large to engage the adjacent edges of the slot when the pin travels through the slot in the operating movementof the switch.
  • a box, switch mechanism mounted therein-and including an operating crank, quick-break mechanism within the box and an external operating handle, said quick-break mechanism includmg a spring pressed disc having a lost motion connection with the handle through the box wall and a single bushing for providing a pivotal support for the operating crank, the disc and the handle, said bushing having shoulders for supporting it in the box and for supporting said disc and handle, said box and handle having interlockingengagement in addition to said bushing.
  • the disc and the handle and said pin having a shoulder overlying the inner edges of the slot.
  • a box hav- 5 a slotted wall, switch mechanism mounted therein and including an operating crank, quick-break mechanism withinthe box and an external operating handle, said' quickbreak mechanism including a spring pressed l0 disc, a pin secured to the handle and extending through the slot in the box wall, and a single bushing providing pivotal support for the operating crank and the disc and being riveted to the handle, said bushing having shoulders for supporting it in the box and for supporting said disc and handle, said pin having a shoulder for interlocking with the edges of said slot in the path oft-movement of said pin.
  • a box having a slotted Wall, switch mechanism mounted therein and including an operating crank, quick-break mechanism and an external operating handle
  • said quick-break mechanism -26 including a disc having a lost motion connection with the handle and a bushing providing pivotal support for the operating crank, the disc and the handle, said bushing having v shoulders for supporting it in the boxand 30 for supporting said disc and handle without binding
  • said lost motion connection includ- V ing a pin riveted to the handle and having a shoulder inside the box for interlocking with the edge of the slot in the wall of the box.
  • a box having a' curved slot in its side wall, switch mechanism mounted in the box and including an operating crank, quick-break mechanism connected to said crank and an external op- 40 erating handle having a pin projecting through the curved slot, said quick-break mechanism including a disc having a lost mo- 1 tion connection with the pin carried by the handle and a one piece bushing providin a support for the operating crank, the and the handle, said pin having a shoulder overlapping the edges of the slot, and said slot having an enlarged portion to permit the insertion of the pin.

Description

Dec. 22, 1931. HAMMERLY 1,838,020
INCLOSED SWITCH Original Filed Jan. 26, 1929 2 Sheets-Sheet 1 21 v; 13 INVENTOR .NNNNNN a H. J. HAMMERLY INCLOSED SWITCH Dec. 22, 1931.
Original Filed Jan. 26, 1929 2 SheetsSheet 2 INVENTORY Patented Dec. 22, 1931 UNITED STATES- PATENT OFFICE :r. HAMMERLY, or WALLINGFORD, comvnc'rrcu'r, ASSIGNOR 'ro TEE TRUM- BULL' nnnc'rmcmmwracrumc comm, or rLAmvILLE, comvncrrcur, A
CORPORATION OF CONNECTICUT I Application filed January 26, 1925 Serial 110 335350. Benewed November 3, 1931.
of switch blades or contacts.
Another object is to provide a quick-make and quick-break mechanism in which the operating movement is started manually but in which the quick movement is spring-pressed and entirely out of control of the operator after the spring movement has once been started.
Another object is to provide a switch construction having an externahoperating handle and an internal loose-connection quickmake and quick-break means so constructed that the quick-make and quick-break means cannot be cramped or bound by any lateral.
pressure that may be applied through the external handle.
Another object-is to provide a construction inwhich a single bushing serves as a support for the operating crank, the quick-break mechanism and the handle, and which bushing is providedwith shoulders for hold ng the parts in position so that they cannot bind and interfere with the quick-break action.
Another object'is to provide a quick-make and quick-break switch construction in which the operating handle and its corelated loose connection parts are secured in position by means of a bushing in such a manner that the operating crank may have a 'relatively loose or endwise shucking engagementwith the' bushing since the crank plays no part in the securing of the loose connection parts in position.
Another object is to provide a switch con-, struction having an external operating handle operably supported in one wall of the box and having a further interlocking en-. gagement with the wall of the box which makes it practically impossible to injure or type.
separate the parts by any ordinary pryin movement of the handle. g Fig. 1 1s a perspective'view of an. inclosed switch embodying my invention and showing the parts of the switch inthe closed circult position with the cover open andbroken awa F1g.'2 is a fragmentary transverse sectional view showing the mounting of the handle, operating crank, and quick-make and break mechanism.
Fig. 3 is a detail edge view showing one form of connector between the operating 1 Fig.1 7 "is a perspective view showing the bushing and associated parts for supporting the crank, the operating handle and the quickbreak mechanism in one wall of the box The box 10 may be of any suitable type and construction and provided with any suitable form of cover 11 and latch 12.
The switch mechanism will usually be mounted upon an insulating base 13 suitably secured in the box. .The operating crank 14 is pivotally supported and adapted to be op-' erated manually by an external handle 15 as will hereinafter be understood.
The invention is particularly applicableto switches for controlling two or more legs of a circuit and will therefore be provided with v such a number of blades and corelated elements as may be required. Each circuit controlling unit usually consists of a knife blade switch and a protecting fuse of any suitable Inthe form shown I have illustrated three switch units but it will be necessary to describe only one which is typical. -The switch jaws 16 and 17 may be of any suitable type for coacting with a switch blade 18. Preferably, this blade is hinged to the jaw. 16 which constitutes a supporting post. Clips, such as 19 are provided for the usual carforms a stop for the on position of the" switch blades and is adapted to strike against 'the insulating base13 when the switch is closed so that the shock of the closing move-' ment is taken .up by the various insulating connectors or plates which are more or less resilient and are not subject to fracture. This foot 21 extends down below the switch blade, as shown in Fig. 3, and whenthe circu'it is opened the upper edge of this foot passes by the adjacent edge of the jaws 17 and serves to cut other interrupt any are which may form between the jaw and the switch blade. This foot 21 may be wider or thicker as shown in Fig. 3 so as to overlap both edges of the jaw 17 Another modification shown in. Fig. 4 embodies two connector plates 20 and 22, the lower ends of which serve as are interrupters adjacent both edges of the jaw 17.
The ends of the operating crank 14 are bent outwardly and supported in the opposite sides of the box. The right hand end 23 has a bearing in the bushing 24. This bushing also supports the oscillating disc 25 and in turn is supported in the opening 26 in the side wall of the box. The washer 27 is supported. on
the bushing outside the box and the outer end of the bushing passes through an opening 28 in the handle and is riveted or spun over at 29 to hold the parts together.
The bushlng 24 is provided with a shoulder 30 forming a bearing'for the disc 25 and a shoulder '31 which constitutes the bearing in the opening 26. The outer portion 32 of the bushing afi'ords support for the washer 27 and the handle. The width of these shoulders 30, 31 and 32 measured in an axial direction is such as to space the disc 25 no matterhow tightly the bushing is riveted over and no matter how the handle is twisted the parts will always be free to operate independently as is necessary in a quickmake and break switch. This is articularly important in. constructions of this character where the box is usually formed of sheet metal and the walls are somewhat flexible.
There should therefore be sufficient freedom swings. The rod 40 is hinged at 41 to the lug 39 and is guided by the bracket 42 at the other end. The spring 43 on the rod 40 presses at one end against the head of the rod 40 near the pivot 41 and the other end is held; in operative position against the bracket 42 by means of the projecting end 'of the bracket in which position the spring affords compression action for the quickmake and quick-break movement.
' When the switch is closed with the parts in the osition shown in Figs. 1, 2 and5, the spring 43 tends to rotate the disc 25 in an anticlockwise direction, as shown in Fig.
against the arm of the crank 14, which crank in turn presses down on the connectors 20 and thus holds the switch blades 18 in the closed circuit position.
In the open circuit position the spring 43 presses the disc 25 in a clockwise direction as viewed in Fig. 6, so that the lug 39 presses against the arm of the' crank 14 which in turn is passed against the stop or abutment IrOnember 45 secured to theinner wall of the ox. I A strap member 46 may be secured on the outside of the box and rovided with suitable. holes or openings or sealing or locking the handle 15 either in the open circuit or closed circuit position.
To close the switch from the position of Fig. 6, the handle is moved upwardly and the pin 33 engages the shoulder" 37 to rotate the disc 25 anticlockwise, thus com- The opening of the circuit/is accomplished.
similarly by the movement of the handle from the position shown in the position shown in Fig. 6. The lost motion space between the shoulders 36 and 37 operating on the disc 25 which alternately engage the pin 33, the lost motion space between the lugs 38 and 39 which alternately engage the arm 14 of the operatin crank and the biasing relation of the sprmg43, all cooperate to provide a uick-makeland a movement of t e switch blades.
The slot 35 is enlarged intermediate its ends and preferably at approximately its center at 35' to permit'the entrance-of the large end of the pin or stud 33 but it is obvious that when the in is moved away from the central position y means of the operatquick-break' ing handle, the shoulder 33' on the pin will overlap the edges of the slot and will thus have a locking'engagement with the wall of the box which cannot be disengaged by .any prying movement of the handle. a
The quick-make and quick-break elements are all secured in position entirely independently of the internal operating crank.
One end of the crank has its bearing in the hole in the bushing 24 and the other end has its bearing in a hole in a wall oi the.
box at the opposite side of the box. As the operating crank has no part in the securing of the other parts in position, this construction permits of considerable endwise orshucking movement of the crank which greatly facilitates the assembling and free action of the parts.
I claim: a 1. In an electric switch, a box, switch mechanism mounted therein and including a switch position and having a recess in which the end of the crank is detachably supported.
2. In an electric switch, a box, switch mech anism mounted therein and including a pivoted switch blade and an operating crank connected thereto, quick-break mechanism within the box and an external operating handle, said quick-break mechanism including a spring pressed disc having a lost motion connection with the handle through the box wall and a single bushing providing a. support for the operating crank, the disc and the handle, said bushing having shoulders for sup porting it in the box and for supporting said disc and handle.
3. In an electric switch, a box, switch mech-' anism mounted therein and including a switch blade, an operating crank, a connector be tween the blade and the crank, quick-break mechanism and an external operating handle, said quick-break mechanism including a disc having a lost motion connection with the handle and a single bushing for supporting the operating crank, the disc and the handle, said bushing having shoulders for supporting it in the box and for supporting said disc and handle. i
4:. A snap action switch comprising a box having a side wall, a bushing rotatably mounted in said wall, a throwing disc mounted on said bushing inside of said box, an operating handle mounted on said bushing outside of said box and having a lost motion connection with said disc through said box wall, and a switch crank having one end detachably mounted in said bushing and lost motion means of connectionbetween said disc and said crank.
5. In an electricsafety switch, \a' box, a
said crank, an operating disc and a handle mounted on said bushing said handle having a pin fastened thereto and movable in-acurved slot in-said box wall, said slot having an en-.
larged portion to permit the insertion of the pin and said pin having a shoulder adapted to overlap and interlock with the inner edge of said slot except at said enlarged portion.
6. In an electric safety switch, a box, a switch operating crank supported at one end in the box wall, said wall having a curved slot concentric about the'end of said crank, an operating handle, a pin rigidly secured to said handle, said pin having shoulders of difierent diameters, one of which movesfreely in the slot, in the box wall and another shoulder being sufficiently large to engage the adjacent edges of the slot when the pin travels through the slot in the operating movementof the switch.
7. In an electric safety switch, a box, switch mechanism mounted therein-and including an operating crank, quick-break mechanism within the box and an external operating handle, said quick-break mechanism includmg a spring pressed disc having a lost motion connection with the handle through the box wall and a single bushing for providing a pivotal support for the operating crank, the disc and the handle, said bushing having shoulders for supporting it in the box and for supporting said disc and handle, said box and handle having interlockingengagement in addition to said bushing.
8. In an electric safety switch, a box,
v switch mechanism mounted therein and lIl-j gcluding an operating crank, quick-break switch mechanism mounted therein and including an operating crank, quick-break mechanism connected to said crank and an external operating handle having a pin projecting, through a curved slot in a wall of the box, said quick-break mechanism including a disc .having a lost motion connection with the handle and a one piece bushing providing a pivotal support for the operating crank,
the disc and the handle and said pin having a shoulder overlying the inner edges of the slot.
10. In an electric safety switch, a box hav- 5 ing a slotted wall, switch mechanism mounted therein and including an operating crank, quick-break mechanism withinthe box and an external operating handle, said' quickbreak mechanism including a spring pressed l0 disc, a pin secured to the handle and extending through the slot in the box wall, and a single bushing providing pivotal support for the operating crank and the disc and being riveted to the handle, said bushing having shoulders for supporting it in the box and for supporting said disc and handle, said pin having a shoulder for interlocking with the edges of said slot in the path oft-movement of said pin.
11. In an electric safety switch, a box having a slotted Wall, switch mechanism mounted therein and including an operating crank, quick-break mechanism and an external operating handle, said quick-break mechanism -26 including a disc having a lost motion connection with the handle and a bushing providing pivotal support for the operating crank, the disc and the handle, said bushing having v shoulders for supporting it in the boxand 30 for supporting said disc and handle without binding, said lost motion connection includ- V ing a pin riveted to the handle and having a shoulder inside the box for interlocking with the edge of the slot in the wall of the box.,
35. f 12. In an electric safety switch, a box having a' curved slot in its side wall, switch mechanism mounted in the box and including an operating crank, quick-break mechanism connected to said crank and an external op- 40 erating handle having a pin projecting through the curved slot, said quick-break mechanism including a disc having a lost mo- 1 tion connection with the pin carried by the handle and a one piece bushing providin a support for the operating crank, the and the handle, said pin having a shoulder overlapping the edges of the slot, and said slot having an enlarged portion to permit the insertion of the pin.
' HERMAN J; HAMMERLY. 1
US335250A 1929-01-26 1929-01-26 Inclosed switch Expired - Lifetime US1838020A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US335250A US1838020A (en) 1929-01-26 1929-01-26 Inclosed switch

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US335250A US1838020A (en) 1929-01-26 1929-01-26 Inclosed switch

Publications (1)

Publication Number Publication Date
US1838020A true US1838020A (en) 1931-12-22

Family

ID=23310933

Family Applications (1)

Application Number Title Priority Date Filing Date
US335250A Expired - Lifetime US1838020A (en) 1929-01-26 1929-01-26 Inclosed switch

Country Status (1)

Country Link
US (1) US1838020A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2574290A (en) * 1947-01-16 1951-11-06 Gen Electric Multiple unit switch with single actuator
US2627919A (en) * 1946-10-05 1953-02-10 Elastic Stop Nut Corp Time-delay control apparatus
US2689278A (en) * 1951-03-23 1954-09-14 Fed Electric Prod Co Quick break actuating mechanism for electric switches
US3422238A (en) * 1967-05-17 1969-01-14 Square D Co Circuit breaker enclosure with external operating handle and combination thereof with circuit breaker
US4524637A (en) * 1982-07-22 1985-06-25 Mitsubishi Denki Kabushiki Kaisha Spring-operated mechanism

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2627919A (en) * 1946-10-05 1953-02-10 Elastic Stop Nut Corp Time-delay control apparatus
US2574290A (en) * 1947-01-16 1951-11-06 Gen Electric Multiple unit switch with single actuator
US2689278A (en) * 1951-03-23 1954-09-14 Fed Electric Prod Co Quick break actuating mechanism for electric switches
US3422238A (en) * 1967-05-17 1969-01-14 Square D Co Circuit breaker enclosure with external operating handle and combination thereof with circuit breaker
US4524637A (en) * 1982-07-22 1985-06-25 Mitsubishi Denki Kabushiki Kaisha Spring-operated mechanism

Similar Documents

Publication Publication Date Title
US1838020A (en) Inclosed switch
US1429275A (en) Electric service switch
US2178600A (en) Safety switch
US1785192A (en) Douple-throw switch
US1780684A (en) Circuit-interrupting device
US2332633A (en) Enclosed switch
US2654011A (en) Electric switch
US1893829A (en) Inclosed switch
US1812896A (en) Switch operating mechanism
US5053590A (en) Mount for attachment of a switch operating mechanism to a switch
GB156632A (en) Improvements in electric switches
US1539104A (en) Switch
US2494314A (en) Electric switch with snap action
US2137872A (en) Electric switch cabinet
US1578422A (en) Inclosed quick-make and quick-break switch
US1755368A (en) Electric-circuit-controlling appliance
US1740858A (en) Electric switch
US2281052A (en) Safety switch
US1587640A (en) Electric switch
US2098559A (en) Safety switch
US2213124A (en) Electric switch
US1843933A (en) Switch operating mechanism
US2096547A (en) Circuit breaker
US2224848A (en) Electric switch
US2020334A (en) Automatic circuit breaker