Electric contactor housing

• US 6,417,749 B1
• Filed: 09/30/1998
• Issued: 07/09/2002
• Est. Priority Date: 09/30/1998
• Status: Expired due to Term

• Current Assignee: Allen-Bradley Company LLC (Rockwell Automation, Inc.)
• Original Assignee: Rockwell Automation Technologies Incorporated (Allen-Bradley Co., Inc.)
• Inventors: Smith, Richard G., Kappel, Mark A., Wieloch, Christopher J., Swietlik, Donald F., Hannula, Raymond H.
• Primary Examiner(s): DONOVAN, LINCOLN D
• Application Number:
  US09/165,013
• Time in Patent Office: 1,378 Days
• Field of Search: 335/8-9, 335/132, 335/202
• US Class Current: 335/132
• CPC Class Codes: H01H 2050/028 Means to improve the overall withstanding voltage, e.g. creepage distances
• CPC Class Codes: H01H 50/026 Details concerning isolation between driving and switching circuit
• CPC Class Codes: H01H 50/546 for contactors having bridging contacts
• CPC Class Codes: H01H 9/362 Mounting of plates in arc chamber
• CPC Class Codes: H01H 9/38 Auxiliary contacts on to which the arc is transferred from the main contacts using arcing-horns H01H9/46
• CPC Class Codes: H01H 9/46 using arcing horns using blow-out magnet H01H9/44

Abstract

A unitary housing structure is provided for an electrical switching device such as a three-phase contactor. The housing includes internal partitions for separating an operator section from contact sections, and for isolating phase sections from one another. The partitions are contiguous with one another and with side walls of the housing, inhibiting plasma flow within the housing cavities. The housing is made of a thermoplastic material which is molded as a single piece. The thermoplastic may be partially protected from plasma and arcs by shields within the phase sections, such as splitter plate supports.

Claims

1. An electrical contactor, the contactor comprising:

an electromagnetic operator;

a polyphase contact portion including parallel phase sections, each phase section having a pair of stationary contacts and a movable contact element displaceable and maintained in a displaced position with respect to the stationary contacts under the influence of the electromagnetic operator to complete and interrupt a current carrying path through the respective phase section;

a one-piece housing body defining a base cavity for receiving the electromagnetic operator and a plurality of contact cavities for receiving respective phase sections, the one-piece housing body including an integral cavity partition to separate the base cavity from the contact cavities and at least one integral phase partition to separate the contact cavities from one another, the one-piece body being made of a moldable thermoplastic material; and

a cap configured to be secured to the body and to fit over the contact cavities.

2. The contactor of claim 1, wherein the at least one phase partition extends from the cavity partition.

3. The contactor of claim 1, wherein the electromagnetic operator includes a base plate and the housing is configured to be secured to the base plate to substantially close the base cavity.

4. The contactor of claim 1, wherein the cavity partition includes at least one aperture for receiving a linking member transmitting motion between the operator and the movable contacts.

5. The contactor of claim 1, further comprising at least one terminal partition coupled to the one-piece housing body, wherein the one-piece housing body includes terminal apertures for each phase section for receiving phase terminals, and the at least one terminal partition is disposed between adjacent terminal apertures.

6. The contactor of claim 5, wherein the one-piece housing body includes a plurality of outwardly extending ribs, at least one rib extending between adjacent terminal apertures on an outer periphery of the housing body.

7. The contactor of claim 1, further including a plurality of arc shields disposed within the contact cavities of the body, the arc shields at least partially shielding the body from arcs generated during operation of the contactor.

8. The contactor of claim 7, wherein the arc shields support splitter plates within each phase section.

9. An electrical contactor, the contactor comprising:

an electromagnetic operator;

a polyphase contact portion including parallel phase sections, each phase section includes a pair of stationary contacts and a movable contact element displaceable and maintained in a displaced position with respect to the stationary contacts under the influence of the electromagnetic operator to complete and interrupt a current carrying path through the respective phase section;

a central housing made of a moldable thermoplastic material, the housing defining a base cavity for receiving the electromagnetic operator and a plurality of contact cavities for receiving respective phase sections, the base cavity being separated from the contact cavities by a transverse partition, and the contact cavities being separated from one another by phase partitions; and

a cap configured to be secured to the body and to fit over the contact cavities.

10. The contactor of claim 9, wherein the transverse partition is integrally formed within the central housing.

11. The contactor of claim 9, wherein the phase partitions are integrally formed within the central housing.

12. The contactor of claim 9, wherein the transverse partition is contiguous with the phase partitions.

13. The contactor of claim 9, wherein the electromagnetic operator includes a base plate and the housing is configured to be secured to the base plate to close the base cavity.

14. The contactor of claim 9, wherein the transverse partition includes at least one aperture for receiving a linking member transmitting motion between the operator and the movable contacts.

15. The contactor of claim 9, further including a plurality of arc shields disposed within the contact cavities of the housing, the arc shields at least partially shielding the housing from arcs generated during operation of the contactor.

16. The contactor of claim 15, wherein the arc shields support splitter plates within each phase section.

17. A method for isolating operative components of an electrical contactor including an electromagnetic operator and a contact assembly having movable contacts selectively displaceable with respect to stationary contacts to complete current carrying paths through the contactor, the method comprising the steps of:

providing a one-piece housing body including a peripheral sidewall defining an interior cavity and a cavity partition integral with the peripheral sidewall and extending transversely from the peripheral sidewall to separate the interior cavity into a base cavity and a contact cavity, the one-piece housing body being molded from a thernmoplastic material;

positioning the electromagnetic operator in the base cavity;

positioning the contact assembly in the contact cavity, the transverse partition isolating the operator from the contact assembly, the operator being configured to be energized for displacing and maintaining the movable contacts with respect to the stationary contacts; and

securing covers to the base and contact cavities.

18. The method of claim 17, wherein the contact assembly includes a plurality of phase sections, and the one-piece housing body further includes at least one phase partition extending from the cavity partition within the contact cavity, and positioning the contact assembly further includes positioning the phase partition between adjacent phase sections.

19. The method of claim 17, wherein the housing body includes terminal apertures for receiving electrical terminals extending from the contact assembly, and wherein the method includes the step of forming a partition on an external peripheral surface of the housing body between adjacent terminal apertures.

20. The method of claim 17, wherein the cavity partition includes at least one aperture for receiving a connecting member for transmitting motion between the operator and the contact assembly, and wherein the method includes the step of coupling the operator and the contact assembly to the connecting member.

21. The method of claim 17, including the further step of positioning internal shields within the contact cavity to at least partially shield the housing body from arcs generated during operation of the contactor.