US3740510A

US3740510A - Contactor with improved contact means

Info

Publication number: US3740510A
Application number: US00136058A
Authority: US
Inventors: K Grunert
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1969-08-27
Filing date: 1971-04-21
Publication date: 1973-06-19
Anticipated expiration: 1990-06-19

Abstract

A contactor comprises improved contact means. The stationary contact structure comprises a conducting support with a contact and arc-runner supported thereon such that the arcs leaving the stationary contact move directly onto the arc-runner. The stationary contact structure is constructed to facilitate removable mounting thereof on a conductor. A metallic shield member is provided to protect the insulating material of the insulating contact carrier from the heat and impact of the bridging contact structure.

Description

United States Patent 1 1 I 1111 3,740,510

[73] Assigneez Westinghouse Electric Corporation,

Grunert' 1 June 19, 1973 [54] (UN'IAC'IOR WITH IMPROVED CONTACT l,857,202 5/1932 lice 200mm K MEANS 3,465.270 9/l969 Schaltlcr HS/U1 [75] Inventor: Kurt A. Grunert, Beaver, Pa.

Primary ExaminerRobert S. Macon Pittsburgh, Pa. A Elchik 22 Filed: Apr. 21, 1971 211 App]. No.: 136,058 [57] ABSTRACT Related [1.5. Application Data A contactor comprises improved contact means. The [62] gg g SS3'Z7lYAUg'27 1969 stationary contact structure comprises a conducting support with a contact and arc-runner supported thereon such that the arcs leaving the stationary cong? 200/166 200/144 tact move directly onto the arc-runner. The stationary 'g R 147 R contact structure is constructed to facilitate removable Attorney-A. T. Stratton, Clement L. McHale and'W.

" 0 335/132 mounting thereof on a conductor. A metallic shield member is provided to protect the insulating material v References Cited of the insulating contact carrier from the heat and im:

pact of the bridging contact structure. UNITED STATES PATENTS 1,149,054v 8/1915 Hoppe eta]. ..2O0/166K 2Claims,6l)rawing Figures i j as 3.5 31 r '1 a p h I ,75 4 3 1 75 -1. 479 55 I 3 79/ 11 1:! 1:1 11 Z EMWH Ufij \1 \73 Sheets-Sheet i1.

W v r? w A a a a ////////1 3 J F a l I Did Patented June 19, 1973 r 3,740,510

2 Sheets-Sheet 2 FIGS.

83 I V//////A 85 v 57 CONTACTOR WITH IMPROVED CONTACT MEANS CROSS-REFERENCE TO RELATED APPLICATION This application is a division of the parent application Ser. No. 853,271 filed Aug. 27, 1969 Now U.S. Pat. No. 3,602,850 issued Aug. 31, 1972.

BACKGROUND OF THE INVENTION 1. Field of the Invention Electric contactors of the type comprising an insulating support and a bridging contact structure resiliently supported on the insulating support.

2. Description of the Prior Art It is old in the art to mount an arc-runner on a conductor adjacent a stationary contact that is supported on the conductor. This invention provides an improved means for supporting a contact and are runner on a conductor such that the arcs leaving the stationary contact more directly onto thearc-runner with the unitary BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a three-pole contactor constructed in accordance with principles of this invention,

FIG. 2 is a side sectional view taken generally along the line II-II of FIG. 1;

FIG. 3 is a perspective view, partly exploded, and

line VI-VI of FIG. 4.

' contact structure. being constructed to facilitate removable mounting thereof on a conductor. This invention also provides improved means for protecting an insulating contact carrier from the heat and impact of a bridg ing contact structure.

SUMMARY OF THE INVENTION bridging contact structure is supported at one end of the tubular .part by spring support meanswhich comprises a saddle member that extends into the tubular .part with'the-bridgin'g contact structure beingpositioned within the saddle member. A coil spring, contained within the tubula'r'partfor protection from the arcs, engages a ledge portion of the contact carrier and one end of the saddle member to bias the saddle memher into the tubular part. 'A damping spring is supported at the outerend of the saddle member between the saddle member and the bridging contact structure whereby the contact-pressure spring operates against the saddle memberwhich operates against the damping spring to bias the bridging contact structure toward the opening of the tubular part into engagement with ledge means of the insulating contact carrier. A metallic heat-sink and impact-absorbing member is supported on the insulating contact carrier between the insulating contact carrier and the bridging contact structure to protect the insulating material of the insulating contact carrier. The bridging contact structure cooperates with a pair of spaced stationary contact structuresthat are disposed in proximity to magnetic arc-extinguishing units. Each of the stationary contact structuresis a three-piece unitary structure comprising a conducting support, a contact supported on the front of the support and an inverted U-shaped arc-runner supported on the support with the bight portion thereof extending into a slot under the contact and with the downwardly extending legs thereof engaging side portions of the support. The support comprises a lower extension having a bolt-recciving opening therein, and the arc-runner is provided with an opening aligned with the opening of the extension to facilitate removable mounting of the contact structure on a conductor.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, there is shown, in FIGS. 1 and 2, a three-pole contactor 5 comprising a housing structure 7 and a contactor-structure 9 supported on the housing structure 7. The housing structure 7 comprises a die cast aluminum base 9, a molded insulating intermediate housing part 10 suitably secured to the base 9, and a molded insulating cover 11 suitably secured to the intermediate housing part 10.

The contactor-structure 9 comprises a generally U- shaped stationary magnetic member 15 supported on the base 9 and a conducting coil 17, encapsulated in an insulating shell 19, supported on the base to energize the contactor. A pair of guide pins 21 are secured to the base 9, and a separate coil kickout spring 23 is supported on each of the guide pins 21. A movable structure 25 is provided to cooperate with the stationary magnetic member 15 in a manner to be hereinafter described. The movable structure 25 comprises an inverted generally U-shaped magnetic armature 27 by means of a connecting rod 31 that rests on ledges 32 of the insulating carrier 29 and passes through an opening in the armature 27. The insulating contact carrier 29 is provided witha pair of openings '33 that receive the guide pins 21. The guide means 21, 33 guide the m'ov-' able-structure 25 for rectilinear reciprocal movement. As can be seen in FIG. 2, the springs 23 bias the movable contact carrier 29 to thereby bias the movable structure 25 outward to the unactuated or deenergized position.

The contactor 5 is a three-pole contactor with three bridging contact structures 35 supported on the insulating contact carrier 29 for simultaneous movement. Each of the bridging contact structures 35 comprises an elongated flat conductor 37 having a pair of contacts 39 fixedly secured thereto in a spaced relationship. As will be best understood with reference to FIG. 3, the insulating contact carrier 29 is formed with three bridging contact structures 35. A pair of slots 42 (only one slot being shown in FIG. 3) is provided in each of the openings of each tubular projection 41 to provide a pair of ledges 43. A separate spring generally U- shaped steel heat 'sink or shield member 45 (FIGS. 2 and 3), having a pair of tangs 47 and a pair offlange portions 49 formed thereon, is snapped down into each bridging contact structure 35 during operation and to serve as a heat sink protecting the molded material of the insulating contact carrier 29 from the heat of the bridging contact structure 25. In each pole unit, a stainless steel saddle member 55 is provided for carrying the associated bridging contact structure 35. Each of the saddle members 55 is provided with a pair of bent-over end portions 57 that protrude through suitable opencontact-pressure spring 61. A sheet-metal damping spring 65, formed with a depression 67 at the center thereof for receiving the front end of the associated saddle 55, is provided in eachpo le unit. The construction of the movable contact structure'25 will be best understood with reference to the assembly and operation of the contactor as will be hereinafter described.

As can be understood with reference to FIG. 2, in each pole unit two rigid flat conductors 71 are supported on the intermediate housing member by bolts 73. Solderless terminal'connectors 75 are secured to the outer ends of the conductors 71 to enable connection of each pole unit in an electric circuit. A separate stationary contact structure 77 is secured to the inner end of each of the conductors 71 by means of a separate bolt 79. As can be understood with reference to FIGS. 4,5 and 6 each of the stationary contact structures 77-is.a three-piece unitary structure comprising a conducting support 81, a contact member 83 and a arcrunner 85. The conducting support 81 is a copper member comprising an extension or mounting part having an opening 87 therein for receiving the associated mountingbolt 79 (FIG. 2). The contact member 83 is a silver cadmium oxide alloy of silver tungsten alloy member that is brazed-to the front of the contact support 81. The arc-runner 85 is an inverted generally U- shaped sheet-metal steel having an opening 89 thereon. The conducting support 81 is formed with a notch (FIG. 4) therein. As can beseen in FIG. 4, the contact 83 comprises an overhanging part that overhangs the notch 91. The arc-runner 85 extends into the notch 91 vwhere it is fixedly brazed to the support. The part of the arc-runner 85 that extends into the notch 91 is a support part and the part that extends away from the contact is an arc-runner part. As can be seen in FIG. 6, parts of the downwardly extending legs ofthe arcrunner 85 engage side surfaces 'of the support 81 to provide additional support of the arc-runner 85 on the support 81. As the arcs leave the contact member 83 they travel directly. onto the arc-runner 85. The opening 89 .permits an operator to insert a screwdriver therethroughin order to removably mount the stationary contact structure 77 (FIG. 2) on the associated conductor 71 by means of the bolt 79. During circuit v ing within the outer ends of the aligned slots.

The assembly of the contactor 5 will be best understood with reference to FIGS. 2 and 3. As can be seen in- FIG. 2, the stationary magnetic member 15 is mounted on the aluminum base 9 by means of a rod 101 that extends through an opening in the member 15 and is secured to the base 9. The coil 19 is supported on the base 9, and the guide pins 21 are screwed into tapped openings in the base 9. The springs 23 are placed over the guide pins 21. The stationary contact structures 77 are secured to the associated terminal conductors 71 by means of the bolts 79 and each conductor 71, with the terminal secured thereto, is secured to the intermediate housing member 10 by means of the associated bolt 73. Each saddle member 55 of each movable contact structure, with the spring 61 and spring support 59 mounted thereon, is moved up through the associated opening in the insulating contact carrier 29 with each of the springs 61 engaging a ledge 105 of the contact carrier 29. After the saddles 59 are in position protruding out past the surfaces 51 (FIG. 3), the shield members 45 are moved into position in the associated openings. Each of the shield members 45 is moved down into position with the associated tangs 47 engaging the associated ledges 43 to retain each shield 45 in place. With the saddles 55 and shields 45 in position, the armature 27 is secured to the contact carrier 29 by means of the bar 31 that it passes through the opening in the armature 25 and engages the ledges 32 on the contact carrier 29 at the opposite ends thereof. The contact carrier 29, with the armature 25 secured thereto, is then moved up through an opening in the intermediate housing member 10 and thereafter the bridging contact structures 35 are mounted in position. As can be seen in FIG. 3, each of the bridging conductors 37 is formed with a pair of notches 107 at 'the opposite sides thereof. Each saddle members 55 is forced upward against the bias of the associated spring 61 and each of the conductors 37 is then tilted at an angle and moved into position through the opening in the associated saddle 55 and then moved so that the notches 107 receive the side legs of the associated saddle 55. Each saddle 55 is forced upwardly to provide sufficient clearance or the damping spring steel member 65 to be moved into the position seen in FIG. 2 with the depressed portion 67 mating with the top portion of the associated saddle 55. Thereafter, upon release of the saddle 55, the associated contact pressure spring 61 will operate against the associated saddle 55 and damping spring 65 to bias the associated bridging conductor 37 downward until the bridging conductor 37 engages the associated flange portions 49 of the associated shield 45. With the movable structure 25 and stationary conductors 71 and stationary contact structures 77 secured to the intermediate housing member 10, the intermediate housing member 10 is moved into the position seen in FIG. 2 and secured to the housing base 9. As can be seen in FIG. 2, the openings 33 in the movable contact carrier 29 are positioned over the guide pins 21 and over the kickout coil springs 23. Thereafter, the housing cover 11, with the arc plates secured thereto, is then moved into position and suitably secured to the intermediate housing member 10. The center pole projection 41 of the insulating contact carrier 29 comprises a front protruding part 109 that protrudes through a suitable opening in the cover 11 to permit manual operation of the contactor and to serve as a guide for the movable structure. A metallic adjustable guide member 111 having a pair of slots therein is secured to the cover 11 by means of a pair of bolts 1 13 which pass through the slots and are screwed into the cover member 11. The slots in the adjustable guide member 111 permit adjusting movement (left-to-right and right-to-left FIG. 2) of the member 111 when the At the large majority of installations the contactor is mounted with the left-hand (FIG. 2) side thereof facing downward so that the part 109 of the contact carrier rests against the member 111 with the engagement between the member 111 and part 109'serving as an externally adjustable guide means enabling a worker to externally adjust the'member 111 to thereby adjust the alignment between the armature 27, of the movable structure 25, and the stationary magnetic member 15.

The operation of the contactor 5 will be best understood with reference to FIG. 2. The contactor is shown in' FIG. 2 in'the de-energized or unactuated position. The coil 17, which is suitably connected in a controlling circuit in a manner well known in the art, is energized to actuate the contactor. Upon energization of the coil 17 the armature 27 is magnetically attracted to the stationary magnetic member to. thereby move the movable structure 25 downward which downward movement is guided by the guide pins 21 and the front part 109. The movable structure 25 moves down against the bias of the kickout springs 23. Downward movement of the movable structure 25 closes the

contacts

39, 83 for all three pole units. After the contacts 39,-83 engage .the armature 27 and contact carrier 29 move downward an additional distance until the armature 27 engages the stationary magnetic member 15 during which additional movement the contactpressu're spring 61 is charged as the ledge portion 105 of the contact carrier 29 biases the contact-pressure spring 61 downward with thespring seat 59 and saddle 55 being restrained from downward movement by the relatively stiff damping spring 65 which operates against the bridging contact structure 35 that is in the closed position. Although the damping spring 65 is stiff enough, relative to the contact-pressure spring 61, that the damping spring 65 will not flatten out as the spring 61 is charged, the damping spring 65 will tend to flatten out the portions thereof that engage the bridging contactrstructure 35- moving laterally (FIG. 2) to thereby provide a damping action against contact bounce when the

contacts

39, 83 are operated to the closed position. As the contact carrier 29 moves downward the additional distance after the

contacts

39, 83 engage, a space is provided between the bridging conductor 37 and the flange portions .49 of the shield 45. Upon deenergization of the coil 17 the kickout springs 23 will return the movable structure 25 to the de-actuated or open position seen in FIG. 2. During the initial part of this movement, the charged contact pressure springs 61- aid in moving the movable structure 25 toward the open position until the bridging conductor 37 engages the flange portions 49 of the shield 45, and thereafter the kickout springs 23 above serve to move the movable structure 25 as a unit to the open position seen in FIG. 2. By interposing the shield 45 between the bridging conductor 37 the molded material of the contact carrier 29 the molded material of the contact carrier 29 is protected from the impacts and heat of the bridging conductor 37.

During opening operations, the'arcs that are drawn between each movable contact 39 and the associated stationary contact 83 are drawn magnetically toward the bight portions of the associated U-shaped magnetic steel plates 95. These arcs move off of the stationary contact button 83 directly onto the arc-runner 85 and along the periphery of the opening 89 (FIG. 5) of the arc-runner 85 toward the bight portions of the plates where the arcs are extinguished in a manner well known in the art. By positioning the magnetic steel arcrunner 85 in the slot 91 (FIG. 4) under a port of the contact button 83, the arcs move directly onto the arcrunner 85 thereby protecting the conducting support 81 and the brazed. joint between the contact button 83 and the conducting support 81. The opening 89 (FIG. 5) in the arc-runner 85 can receive a screwdriver type tool to facilitate removable mounting of the three-piece unitary contact structure 77 on the associated conductor 71 by means of the associated bolt or screw 79. I claim as my invention:

1. A contactor comprising an insulating contact carrier, a bridging contact structure, spring support means supporting said bridging contact structure on said insulating contact carrier, a metallic heat sink separate fromsaid spring support means supported on said insulating contact carrier in a position interposed between said insulating contact carrier and said bridging contact structure, said insulating contact carrier comprising a tubular part, said bridging contact structure being an elongated structure supported at one end of said tubular part across the opening of said tubular part, said metallic heat sink comprising 'a generally U-shaped part and a pair of flange parts extending outward from .the

opposite legs of said U-shaped part, said metallic heat sink being positioned on said tubular part with the U- shaped part thereof being disposed in said tubular part and with said flange parts being positioned on the end surface of said tubular part, and said spring support means biasing said elongated bridging contact structure against said flange portions in the open position of said bridging contact structure.

2. A contactor according to claim 1, said tubular part having ledge means therein, and said metallic heat sink comprising resilient tang means cooperable with said ledge means such that said heat sink is mounted on said tubular part by being forced into the mounted position thereof with said resilient tang means automatically cooperating with said ledge means to retain said metallic heat sink in the mounted position.

a t: w a k

Claims

1. A contactor comprising an insulating contact carrier, a bridging contact structure, spring support means supporting said bridging contact structure on said insulating contact carrier, a metallic heat sink separate from said spring support means supported on said insulating contact carrier in a position interposed between said insulating contact carrier and said bridging contact structure, said insulating contact carrier comprising a tubular part, said bridging contact structure being an elongated structure supported at one end of said tubular part across the opEning of said tubular part, said metallic heat sink comprising a generally U-shaped part and a pair of flange parts extending outward from the opposite legs of said U-shaped part, said metallic heat sink being positioned on said tubular part with the U-shaped part thereof being disposed in said tubular part and with said flange parts being positioned on the end surface of said tubular part, and said spring support means biasing said elongated bridging contact structure against said flange portions in the open position of said bridging contact structure.