US3737821A - Electrical contactors - Google Patents

Electrical contactors Download PDF

Info

Publication number
US3737821A
US3737821A US00183489A US3737821DA US3737821A US 3737821 A US3737821 A US 3737821A US 00183489 A US00183489 A US 00183489A US 3737821D A US3737821D A US 3737821DA US 3737821 A US3737821 A US 3737821A
Authority
US
United States
Prior art keywords
fulcrum
point
contactor
contact
conductive strap
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
US00183489A
Other languages
English (en)
Inventor
J Morton
H Grove
K Stevens
G Spencer
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.)
Cableform Ltd
Original Assignee
Cableform Ltd
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 Cableform Ltd filed Critical Cableform Ltd
Application granted granted Critical
Publication of US3737821A publication Critical patent/US3737821A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H50/00—Details of electromagnetic relays
    • H01H50/16—Magnetic circuit arrangements
    • H01H50/18—Movable parts of magnetic circuits, e.g. armature
    • H01H50/20—Movable parts of magnetic circuits, e.g. armature movable inside coil and substantially lengthwise with respect to axis thereof; movable coaxially with respect to coil
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H1/00—Contacts
    • H01H1/58—Electric connections to or between contacts; Terminals
    • H01H1/5822—Flexible connections between movable contact and terminal

Definitions

  • ABSTRACT- 211 Appl' l83489
  • a solenoid operated contactor which provides a larger than armature travel air gap, higher con- Foreign Application Priority Data tact pressures and rolling or wiping action of the main Sept 25 1970 Gm England 709/ contacts, by providing a conductive strap supporting the main moving contact, which strap is coupled inter- 521 U.S. c1 ..335/133, 200/166 .l 335/200 mediate ends mature and has 51 Int.
  • the attracted armature or clapper type Two main types of contactors are presently in use, the attracted armature or clapper type and the solenoid operated type. Of these .two, the attracted armature type is much more widely used, although it tends to be larger and more expensive, as its geometry is more convenient for incorporating arc blow out devices, wiping or rolling actions on the main contacts and larger air gaps between main contacts for a given air gap in the magnetic circuit. To achieve this larger air gap it is necessary to have a velocity ratio which has the disadvantage of giving the lowest of the two or more reactions to the armature force at the main contact and therefore less contact pressure for a given force on the armature.
  • a solenoid contactor has the advantage that it can be constructed in a smaller volume and with less parts but in general rolling or wiping action on the main contacts is not available nor is the facility for are blow out, greater air gaps between main contacts than armature travel or a greater air gap between main contacts than armature travel and yet still maintaining the largest reaction to the armature force on the main contact.
  • a solenoid operated contactor comprises a fixed contact and a co-operating moving contact, the latter being carried at or towards one end of a conductive strap which is coupled intermediate its end to the solenoid armature, the strap in the portion beyond the armature-strap coupling remote from the moving contact having alternative fulcra of different spacings from the armature-strap coupling, the arrangement being such that when the solenoid is tie-energized the fulcrum nearer the armature-strap coupling is operative and when the contactor is fully operated the fulcrum more distant from the armaturestrap coupling is operative.
  • the strap is electrically connectedto the more distant fulcrum by a flexible conductor .
  • a flexible conductor which as will be explained latter providesmeans enabling thereduction of duration of contactbounce for a given mass of moving components and closing'velocity.
  • FIG. 1 is a diagrammatic representation of the contact assembly in the closed condition, in accordance with the invention.
  • FIG. 2 is a similar representation to thatof FIG. 1 but showing the open condition
  • FIG. 3 is a similar representation of a change-over contact assembly
  • FIG. 4 is a part-sectional view of a contactor in accordance with the invention.
  • FIG. 5 is a view at right angles to, that of FIG. 4.
  • the contact assembly comprises a strap carrying a moving contact 11 cooperating with a fixed contact 12.
  • the strap is coupled to a solenoid armature (not shown) at 13 so that the strap experiences the force F when the solenoid is energized and a spring return force F 1 when it is dethe fulcrum B by a flexible conductor 15 in the form of braid.
  • the clearance in the direction of the solenoid axis is so arranged that when the solenoid is energized the contacts close (positions 2) and the solenoid continues to travel until the other end of the conducting strap closes on to the fulcrum B (Position 1), thus causing the moving contact 11 to roll on the fixed contact 12.
  • the velocity of the moving contact assembly only undergoes a small change at this moment due to a slight change in direction, the velocity of the whole assembly being relatively unaffected.
  • the assembly continues to travel until the moving contact assembly is brought into contact with the fulcrum B.
  • the velocity of the moving contact assembly now undergoes a major change and oscillation of the moving contact assembly with respect to the fulcrum B now takes place.
  • FIG. 3 there is shown diagrammatically a similar contact assembly with the exception that contacts 16 and 17 are provided at the fulcrum E and projection 14. As can be seen from FIG. 1 and 2 contact between fulcrum E and projection 14 is open when contacts 11 and 12 are closed and closed when contacts l1 and 12 are open. Thus a change-over contact assembly is provided, the movement between the position 3 and 4 shown in FIG. 2 providing a very positive wiping action for the contacts 16 and 17.
  • the contactor comprises a solenoid 20 having an operating coil 21 and a plunger 22 from which extends an operating rod 23 carrying an insulating collar 24 which is urged upwards by a coil spring 25 bearing on a base plate 26.
  • Collar 24 supports the conductive strap 10 carrying the moving contact 11 co-operating with the fixed contact 12 mounted on a terminal assembly 27 which is secured to the base plate 26 by bolt 28. Strap 10 is held on the collar 24 by a light blade spring 29 and retaining ring assembly 30.
  • Strap 10 is provided with the L-shaped projection 14 which co-operates with fulcrum E which is an extension from a terminal assembly 31 which is mounted on base plate 26 and also provides fulcrum B.
  • the flexible conductor 15 extends from a lug 32 on terminal assembly 31 to the end of strap 10. The operation of the contactor is as already described in relation toFlGS. 1 and 2.
  • An arc chute assembly 33, 34 provided with permanent magnets 35, 36 is positioned adjacent the contacts 11, 12 to act as an arc blow out device.
  • the magnets are positioned to achieve maximum flux density across the contact gaps to pull the are out as quickly as possible.
  • the are chute assembly serves to locate the assem bly of the moving contact and the overtravel spring to the desired position relative to the fixed contact.
  • a first fulcrum positioned for contact with said conductive strap at a point on the opposite side of the point of said coupling from the point at which said moving contact is carried
  • a second fulcrum also positioned for contact with said conductive strap at a point on the opposite side of the point of said coupling from the point at which said moving contact is carried, but at a point more distant from the point of said coupling than the point at which said first fulcrum is positioned,
  • said first and second fulcra being operatively associated with said conductive strap so that, when the solenoid is d e-energized, said first fulcrum is operative and,'when the contactor is fully operated, said second fulcrum is operative.
  • a contactor as claimed in claim 1 wherein said conductive strap has a main member which carries said moving contact and which co-operates with said second fulcrum and I a generally L-shaped projection which co-operates with said first fulcrum, said first fulcrum extending into the space between the remote leg of said L- shaped projection and said main member.
  • a contactor as claimed in claim 1 wherein a first additional contact is mounted on said conductive strip at the point where it contacts said first fulcrum and a second additional contact is mounted on said first fulcrum,
  • a contactor as claimed in claim 1 wherein said solenoid armature is coupled to said conductive strap via an insulating collar which also serves as an abutment for one end of a throw-off coil spring, said conductive strap being steadied on said insulting collar by a blade spring.
  • a contactor as claimed in claim 1 further comprising an arc chute including permanent magnets adjacent said fixed contact and said moving contact, the arc chute serving to locate the assembly of said moving contact and said conductive strap to the desired position relative to said fixed contact.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Arc-Extinguishing Devices That Are Switches (AREA)
  • Push-Button Switches (AREA)
  • Electromagnets (AREA)
US00183489A 1970-09-25 1971-09-24 Electrical contactors Expired - Lifetime US3737821A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB4570970A GB1366889A (en) 1970-09-25 1970-09-25 Electrical contactors

Publications (1)

Publication Number Publication Date
US3737821A true US3737821A (en) 1973-06-05

Family

ID=10438258

Family Applications (1)

Application Number Title Priority Date Filing Date
US00183489A Expired - Lifetime US3737821A (en) 1970-09-25 1971-09-24 Electrical contactors

Country Status (5)

Country Link
US (1) US3737821A (Direct)
DE (1) DE2148177A1 (Direct)
FR (1) FR2107995B1 (Direct)
GB (1) GB1366889A (Direct)
SE (1) SE365897B (Direct)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3864649A (en) * 1970-11-09 1975-02-04 Rucker Co Electrical safety device with improved trip mechanism

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102012006438A1 (de) 2012-03-30 2013-10-02 Phoenix Contact Gmbh & Co. Kg Relais mit zwei gegensinnig betätigbaren Schaltern

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3076073A (en) * 1960-10-03 1963-01-29 Gen Electric Contactor
US3135841A (en) * 1959-08-18 1964-06-02 Dole Valve Co Snap acting switch
US3345476A (en) * 1962-04-27 1967-10-03 Penn Controls Fool-proof snap action reset switch
US3550049A (en) * 1968-07-05 1970-12-22 Merlin Gerin Current limiting circuit breaker with electrodynamic compensation
US3623150A (en) * 1969-01-20 1971-11-23 Dewhurst & Partner Ltd Contactor switch

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3135841A (en) * 1959-08-18 1964-06-02 Dole Valve Co Snap acting switch
US3076073A (en) * 1960-10-03 1963-01-29 Gen Electric Contactor
US3345476A (en) * 1962-04-27 1967-10-03 Penn Controls Fool-proof snap action reset switch
US3550049A (en) * 1968-07-05 1970-12-22 Merlin Gerin Current limiting circuit breaker with electrodynamic compensation
US3623150A (en) * 1969-01-20 1971-11-23 Dewhurst & Partner Ltd Contactor switch

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3864649A (en) * 1970-11-09 1975-02-04 Rucker Co Electrical safety device with improved trip mechanism

Also Published As

Publication number Publication date
DE2148177A1 (de) 1972-03-30
FR2107995B1 (Direct) 1976-09-03
SE365897B (Direct) 1974-04-01
FR2107995A1 (Direct) 1972-05-12
GB1366889A (en) 1974-09-18

Similar Documents

Publication Publication Date Title
US2569281A (en) Contact mechanism for automatic circuit breakers and similar electrical switchgear
US2415448A (en) Snap switch
US3737821A (en) Electrical contactors
US1991113A (en) Electromagnetic switch
US1941273A (en) Vacuum switch
US1839629A (en) Push button switch for elevators
US2284621A (en) Electromagnetic relay
US2432782A (en) Electric switch
US3713055A (en) Auxiliary contact system for electromagnetic switching devices
US2524874A (en) Electromagnetic relay construction
CA1109906A (en) Magnetic latch device for a clapper type contactor
US3825865A (en) Electromagnetic relay
US3165608A (en) Magnetic switching apparatus for reducing contact bounce
US3395259A (en) Electromagnetic contactor having improved knife-edge pivoted armature structure, insulating stop means and releasable arc shield
GB1047464A (Direct)
US2946875A (en) Electromagnetic relay
US1855804A (en) Electromagnetic switch
US2669620A (en) Electromagnetic contactor
US3922625A (en) Electro-magnetic relays
US2134179A (en) Electric switch
US3118988A (en) Electromagnetic relay with conductive core and conductive housing
US2538037A (en) Magnetic switch operating mechanism
US1231412A (en) Electromagnetic switch.
US2841670A (en) Frictionless plunger switch having alignable self-holding contacts
US2370038A (en) Latched-in magnetic switch