US3727157A

US3727157A - Electric control device

Info

Publication number: US3727157A
Application number: US00218104A
Authority: US
Inventors: K Grunert; T Rehm; C Paton
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1972-01-17
Filing date: 1972-01-17
Publication date: 1973-04-10
Anticipated expiration: 1990-04-10
Also published as: BR7300353D0

Abstract

An electric control device or contactor adapted for mounting on a mounting panel and comprising an electrically insulating housing and a mounting bracket the latter of which is fixedly attached to a mounting panel and the former of which is readily detachably mounted on the bracket for easy access to the interior of the device; and means separable from the housing and bracket comprising an elongated wire-like member having end portions engaging wire-engaging means in the housing and in the mounting bracket.

Description

o Waited States Patent 11 1 1 1 3,727,157 Grunert et a1. [4 Apr. 10, 1973 [54] ELECTRIC CONTROL DEVICE 3,202,785 8/1965 Jelley ..335/132 3,215,800 11/1965 Hurteretal. ..200/168C [75] Inventors: Kurt A. Glnmert; Thomas R. Rehm,

both Beaver; c Pam, Primary Examiner-Harold Broome New Bl'lghton, an of Attorney-A. T. Stratton et a1. [73] Assignee: Westinghouse Electric Corporation,

' Pittsburgh, Pa. [57] ABSTRACT [22] Filed: Jam 17, 1972 An electric control deyice or contactor adapted for mounting on a mounting panel and comprising an [21] Appl. No.: 218,104 electrically insulating housing and a mounting bracket the latter of which is fixedly attached to a mounting panel and the former of which is readily detachably [52] US. Cl .335/132, 200/168 mounted on the bracket for eas access to the interior 51 r y at. C1. ..H0111 50/04 of the device; and means separable from the housing of Search 1 and bracket comprising an elongated wire ]ike 3 200/163 163 317/119 member having end portions engaging wire-engaging I means in the housing and in the mounting bracket. [56] 7 References Cited 7 Claims, 7 Drawing Figures UNIT ED STATES PATENTS 3,102,935

9/1963 Christeler ..-...335/202 PATENTEU APR 1 0 m5 SHEET 1 OF 3 PATH-HEW 1 01m 3'. 727. 157

SHEET 2 OF 3 ELECTRIC CONTROL DEVICE CROSS REFERENCE TO RELATED APPLICATIONS This invention is related to the invention disclosed in BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to an electric control device such as a contactor or relay and, more particularly, it pertains to readily detachable means for assembling and disassembling the device.

2. Description of the Prior Art Electric control devices such as contactors and relays are usually mounted on a mounting panel in proximity to other electrical device for convenience and accessibility. Most prior known contactors have been constructed in such a manner that any repair requires removal of the entire contactor from the mounting panel. That procedure has been a nuisance and time consuming. For example, in the past the replacement or change of a magnetic coil due to a required change in specifications such as from 24 volts to 120 volts has involved the steps of first removing the entire electro-magnetically operated connector from its mounted position and then disassembling the same for access to the interior thereof, after which the device is reassembled and remounted on the mounting panel.

Associated with the foregoing has been a problem of an assembly for contactors and relays of the electromagnetic type which involve a magnetic flux path. More particularly, prior known contactors have included an excessive number of parts for providing an actuator structure containing a magnetic coil, a magnetic field return path, as well as a support member for an insulating housing.

SUMMARY OF THE INVENTION In accordance with this invention, it has been found that the foregoing problems may be overcome by providing an electric control device for mounting on a mounting panel comprising an assembly of an electrically insulating housing and a mounting bracket for fixedly attaching the assembly to the mounting panel, the housing comprising a stationary contact structure, a movable contact carrier structure within the housing and movable between open and closed positions relative to the stationary contact structure, biasing means for holding the movable contact carrier structure in one of the operating positions, such as the open position, electromagnetic means for actuating the contact carrier structure to the other operating position, such as the closed position and comprising a magnetic coil and an armature, the magnetic coil being mounted on the mounting bracket and the armature being mounted on the movable contact carrier structure, separate means for readily detachably mounting the housing on the bracket for enabling easy access to the interior of the assembly without removing the bracket from the mounting panel which means includes a wire clip having spaced portions engageable with the housing and the mounting bracket. It is a salient feature of this invention that the assembly of the insulating housing, the

stationary contact structure, the movable contact carrier structure, the biasing means, and the armature comprise a unitary assembly that is removable as a unit from the mounting bracket.

The advantage of the device of this invention is the provision of means for expedient access to the interior of an electrical contactor without the necessity of removing the complete contactor from a mounting panel by providing easily detachable mounting means.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view of an electric control device or contactor in accordance with the principles of this invention;

FIG. 2 is a plan view of the device shown in FIG. 1;

FIG. 3 is a vertical sectional view taken substantially on the line III-III of FIG. 2;

FIG. 4 is a vertical sectional view taken on the line IVIV of FIG. 2;

FIG. 5 is an enlarged, fragmentary, sectional view showing the attachment between the wire clip and the bracket;

FIG. 6 is a side elevational view of another embodiment of the invention; and

FIG. 7 is an end view taken on the line VI-VI of FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 1, an electric control device or contactor is generally indicated at 10 and it comprises a housing 12 and a mounting bracket 14. In addition, as shown in FIG. 4, the device 10 also includes a movable contact carrier structure 16 and electromagnetic means 18 for actuating the contact carrier structure.

The housing 12 is composed of an electrically insulating or dielectric material such as a phenolic resin. The contactor 10 is a multipole type such as a two-pole contactor. The housing 12 is a shell-like member having a top wall 20 (FIG. I),

opposite side walls

22 and 24, and

opposite end walls

26 and 28. The housing also includes a pair of spaced partitions 30 and 32 (FIG. 2) which extend between the

end walls

26 and 28. As shown more particularly in FIG. 2, a pair of

spaced walls

34 and 36 extend downwardly from the top wall 20 between the

partitions

30 and 32. A wall 38 also extends downwardly from the top wall 20 between the

walls

34 and 36 and parallel to the

partitions

30 and 32. The wall 38 has a lower end 40 which serves as a stop for limiting upward movement of the movable contact carrier structure 16.

In FIGS. ll, 2 and 3, four

stationary contact structures

42, 44, 46 and 48 are provided in pairs at

opposite end walls

26 and 28. As shown more particularly (FIG. 1) for the

contact structures

42 and 46, the contact structures are disposed between similar spaced pairs of

partitions

50 and 52 extending outwardly from the

end walls

26 and 28. Each' stationary contact structure 42-48 comprises a U-shaped conducting strap 54 (FIG. 3), a terminal screw 56, stationary contacts 58, and wire connecting terminals 60. Each conducting strap 54 has an upper portion extending through an opening 62 in the

end Walls

26 and 28 and is disposed in a chamber 64 between the side wall 24 and the partition 32. A similar chamber 64 is disposed between the side wall 22 and the partition 30 and both chambers extend between the

end walls

26 and 28. The stationary contacts 58 are in vertical path of travel of a movable contact 66. The terminal screw 56 secures the conducting strap 54 in place on a projecting portion 68 of the wall 28. The terminals 60 extend outwardly to facilitate connection of a lead wire thereto in a conventional manner.

As shown in the drawings,.the top wall 20 is provided with a pair of spaced

openings

70 and 72 which communicate separately with the chambers 54. Likewise, similar openings 74 are provided in the top wall each of which is in substantial alignment with the path of travel of each-corresponding movable contact 66.

In FIGS. 1 and 2, a vertically extending slot 76 is provided between the partitions 52 which slot is aligned with a screw-receiving notch 78. One notch 78 is preferably disposed at each end of the mounting bracket 14 whereby the bracket may be attached by screws 80 (one of which is shown in FIG. 1) to a mounting panel 82. Alignment of the slot 76 with a corresponding notch 78 enables placement of the shank of the screwdriver in the slot for setting screws 80 in place.

Finally, the housing 12 is provided with four openings 84 near opposite corners of the device. The openings 84 cooperate with a U-shaped member or clip 86 for securing the housing 20 to the mounting bracket 14 in a manner to be described below.

The mounting bracket 14 is a U-shaped member having upturned

legs

88 and 90 and an intermediate base 92. The bracket is composed of a ferromagnetic material, such as low'carbon steel, for example, cold rolled steel plate. In the alternative, the bracket 14 may be composed of a ferromagnetic material fabricated by pressing powdered low carbon steel in a mold and then sintering at an adequate temperature to form a coherent rigid member. The mounting brackets 14 serve as a magnetic field path for an electro-magnetic field generated by a magnetic coil 94 which is part of the electromagnetic means 18.

The electric control device or contactor is provided with detachable mounting means for releasably supporting the housing 12 on the bracket 14. The detachable mounting means extends between the housing 12 and the bracket 14 and is either completely separable therefrom or is detachable from one or the other of the housing and the bracket. For example, one embodiment of the detachable mounting means is that shown in FIGS. 1 to 4 which includes the U-shaped member or clip 86 which is preferably a wire clip which cooperates with suitable attaching means on the housing end bracket. For that purpose a projection 96 is provided on each outer surface of the upturned legs 88 and 90 (FIG. 5) to which the clip 86 is attached. The clip 86 includes a pair of similar legs 98 (FIG. 1) as well as an intermediate .portion 100 therebetween. As shown in FIG; 4, the upper ends of each leg 98 include a hooked portionhaving downturned prongs 102 each of which is disposed in one of the openings 84 of the housing 12. In the assembled condition of the device 10, the intermediate portions 100 of the wire clip 86 are disposed along the lower edge of the member 96 as shown in FIGS. 1 and 4, whereby the housing 12 and the bracket 14 are secured together.

bending or deflecting the intermediate portions into place. For that purpose, as shown in FIG. 5, each projection 96 includes an inwardly and upwardly inclined undersurface 104, whereby the intermediate portion 100 is retained in place against the outer surface of the upturned leg 90.

Another embodiment of the detachable mounting means is shown in FIGS. 6 and 7. It differs from the embodiment of FIGS. 1 to 5 in that it includes an elongated member or wire clip 106 on each side of the device 10 instead of the U-shaped clips 86 of FIGS. 1 to 5. Like the clip 86 the clips 106 are elastically deformable members which during assembly and disassembly of the unit 10 are slightly bent out of shape. Each clip 106 has a hooked upper end portion including a downturned prong 108 (FIG. 7) which is seated in an opening 110 on each side of the housing 12. The lower end of the clip 106 includes an intumed end portion 1 12 which extends through a hole 1 14 in each

upturned leg

88 and 90 of the bracket 14. As shown more particularly in FIG. 7 an innermost end portion 116 of the inturned end portion 112 is curved upwardly toward the prong 108 of the corresponding clip 106, whereby when in the assembled position, the intumed end portion 112 is secured in place within the corresponding hole 114 without accidental detachment therefrom. Inasmuch as the clip 106 is an elastically deformable member, the clip may be inserted or removed from the position shown in FIG. 7 by a slight deformation of the end portion 112, either manually or with the aid of a screwdriver blade, for forcing the inner end 116 through the hole 114.

The movable contact carrier structure 16 comprises a generally U-shaped contact carrier member 118, a magnetic armature 120, and separate bridging contact members 122. The contact carrier member 118 is composed of an electrically insulating material such as phenolic resin. As shown in the drawings, the contact carrier member 1 18 is movably mounted in the housing 12 with upper ends of the U-legs extending into the

openings

70 and 72 of the housing. Thus, one leg of the member 118 is disposed in one chamber 64 and. the other leg is disposed in the other chamber 64 with a lower intermediate portion or crossbar 124 (FIG. 4) extending therebetween and under the

partitions

30 and 32. In addition, each leg of the member 118 is provided with a projection or car 126 (FIG. 1, 2 and 4) which extends outwardly in opposite directions from each other and through vertically slotted openings 128 and of

opposite side walls

22 and 24, whereby the member is guided without bindingin the housing during vertical movement.

As indicated above, the contact carrier member 118 also includes a pair of bridging contact members 122 which extend FIG. 3) between corresponding pairs of spaced stationary' contacts 58. The movable contacts 66 are secured to opposite ends of the bridging contact members 122, which are preferably composed of metal. As shown in FIG. 4, each member 122 extends through a window 130, one window being provided in the upper end of each U-leg of the contact carrier member 118. In each of the windows, a compression spring 1.32 holds the associated bridging contact member 122 in place to provide for resilient contacting engagement between the corresponding movable contacts 66 and stationary contacts 58 in a manner similar to that set forth in the above mentioned US. Pat. No. 3,296,567.

The electromagnetic means 18 also includes a plate 132 which extends between upper end surfaces 134 and 136 of the

upturned legs

88 and 90 of the mounting brackets 14. The plate 132 is located between the coil 94 and the crossbar 124 for the purpose of completing the loop of the electromagnetic field when the mag netic coil 94 is actuated. The plate 132 has a central aperture 138 that is aligned with the axis of the coil 94. As shown in FIGS. 3 and 4, the coil 94 includes a spool 140 on which the coil wire is wound. The spool 140 is composed of an electrically insulating material such as nylon resin. The spool 140 is centrally disposed in the bracket 14 and surrounds a magnetic core 142 that is fixedly mounted at 144 in the bracket 14.

As shown the spool 140 includes a collar 145 which extends into the aperture 138 of the plate 132 above the spool. The collar 145 prevents frictional contact of the armature 120 with the plate and thereby maintains an efficient flow of a magnetic field around the loop formed by the bracket 14 and the plate 132.

The armature 120 and the core 142 are metallic members having ferromagnetic properties such as low carbon steel. The armature 120 includes means for attachment to the crossbar 124 such as a stem 146 with an enlarged head 148 (FIG. 4) that are seated in a slot 150 in the crossbar. When the coil is actuated, the armature 120 is pulled downwardly toward the core 142 against the force of a coil spring 152 which is disposed between the plate 132 and the cross-bar 124 and which normally holds the U-shaped contact carrier member 118 in the upper position as shown in FIG. 3. In FIG. 4 a central portion 154 of the carrier member 118 is located on the crossbar 124 between the upright portions of the carrier member and thereby cooperates with the lower end 40 of the wall 38 to limit upward travel of the carrier member by the coil spring 152.

Finally, the pole M2 is provided with a shading coil 156 which is preferably a ring of copper that is seated by press fit into a corresponding slot in the upper end of the core 142. The shading coil 156 provides a force component that bridges the zero force condition of the sine curve (A.C. current) by creating an out-of-phase field with the main (sine) curve and thereby avoiding mechanical noise or chatter that would otherwise occur.

Accordingly, the electric control device or contactor of the .present invention satisfied certain problems which were extant in devices of prior art construction including means for readily detaching the insulating housing from the mounting bracket for facilitating access to the interior of the device without completely removing the mounting bracket from a mounting panel,

and including the incorporation of structural features to avoid potential binding between the crossbar and the housing.

What is claimed is:

ll. An electric control device for use on a mounting panel comprising an assembly of an electrically insulating housing and of a mounting bracket for fixedly attaching the assembly to a mounting panel, the mounting bracket being a U-shaped member having upturned legs and an intermediate base, the housing comprising a stationary contact structure, a movable contact carrier structure within the housing and movable between open and closed positions relative to the stationary contact structure, biasing means for holding the movable contact carrier structure in one of the positions, electromagnetic means for actuating the contact carrier structure to the other of the positions and comprisstructure and the intermediate base of the mounting bracket, the armature being mounted on the other of the movable contact carrier structure and the intermediate base of the mounting bracket, separate means for' readily detachably mounting the housing on the bracket for enabling easy access to the interior of the assembly without removal'of the bracket from a mounting panel and comprising a pair of elastically deformable elongated members detachably mounted on opposite sides of the assembly, each member having a U- shaped configuration comprising a pair of second legs and an intermediate portion, each second leg having an inturned end portion engageable with the housing, and the intermediate portion being engageable with the corresponding upturned leg of the mounting bracket.

2. The device of claim I wherein the magnetic coil is mounted on the mounting bracket and the armature is mounted on the movable contact carrier structure.

3. The device of claim 1 wherein the mounting bracket comprises a generally U-shaped ferromagnetic member, the electromagnetic means also comprises a magnetic core mounted on the intermediate base, and the magnetic coil is disposed in the bracket and around the core.

4. The device of claim 1 wherein the deformable structure is an elongated wire-like member having spaced portions engageable with the housing and the mounting bracket.

5. The device of claim 1 wherein the detachable mounting means comprises a wire clip, a first surface on the housing, and a second surface on the mounting bracket, and the wire clip having spaced portions one portion being engageable with the first surface and the other portion being engageable with the second surface.

6. The device of claim 1 wherein the first surface comprises a first wire-receiving opening and the second surface comprises a second wire receiving opening.

7. The device of claim 2 wherein said insulating housing, said stationary contact structure, said movable contact carrier structure, said biasing means, and said armature forming a unitary assembly removable as a unit.

Claims

1. An electric control device for use on a mounting panel comprising an assembly of an electrically insulating housing and of a mounting bracket for fixedly attaching the assembly to a mounting panel, the mounting bracket being a U-shaped member having upturned legs and an intermediate base, the housing comprising a stationary contact structure, a movable contact carrier structure within the housing and movable between open and closed positions relative to the stationary contact structure, biasing means for holding the movable contact carrier structure in one of the positions, electromagnetic means for actuating the contact carrier structure to the other of the positions and comprising a magnetic coil and an armature, the magnetic coil being mounted on one of the movable contact carrier structure and the intermediate base of the mounting bracket, the armature being mounted on the other of the movable contact carrier structure and the intermediate base of the mounting bracket, separate means for readily detachably mounting the housing on the bracket for enabling easy access to the interior of the assembly without removal of the bracket from a mounting panel and comprising a pair of elastically deformable elongated members detachably mounted on opposite sides of the assembly, each member having a U-shaped configuration comprising a pair of second legs and an intermediate portion, each second leg having an inturned end portion engageable with the housing, and the intermediate portion being engageable with the corresponding upturned leg of the mounting bracket.

2. The device of claim 1 wherein the magnetic coil is mounted on the mounting bracket and the armature is mounted on the movable contact carrier structure.