Patent Application
20110250776
The invention is directed to a further advancement in the field of electrical connector assemblies. More specifically, this application relates to a slotted outer retainer ring for a snap-fit electrical connector assembly and having a construction for facilitating efficient connection and disconnection of the connector assembly to an electrical box.
Electrical connectors are commonly used for attaching electrical conductors, cables, wires, electrical metal tubing (EMT) or the like to an electric box, e.g. a junction box, outlet box, switch box, fuse box, or other similar type of electric box. Such known electrical connectors are either of a type that are secured to an electric box by a threaded locknut or by means of a circular snap fit retainer ring of the type disclosed in U.S. Pat. Nos. 6,860,758; 6,444,907; 5,189,258; 5,266,050; and 5,171,164, for example.
So called “snap fit” connectors have been in use for some time, including connectors disclosed in Applicant's U.S. Pat. Nos. 7,064,272; 7,075,007; 7,205,489 and 7,214,890. Such connectors have typically been coupled to the junction box by forcibly inserting one end of the connector into the knock-out hole of a junction box. Such connectors include a circular retainer ring which is deformed during insertion of the connector body into a knock-out hole. In the past, a generally linear motion has been used to insert the connector end into the junction box. Using such a straight motion, the connector end is pushed into the knock-out hole so as to deform a retainer ring as it passes through the knock-out hole.
A significant limitation of some prior art connector assemblies is the difficulty in removing or repositioning the connector assembly once the outer retainer ring is inserted into an electrical box.
The present invention provides a connector assembly having a retainer ring for securing a connector body to an electrical box.
An embodiment of the present invention includes a slotted retainer ring having a slot adapted to receive a common tool, such as a screwdriver, to facilitate removal of the retainer ring from inside the electrical box. In one embodiment, the slot of the retainer ring is aligned generally perpendicular to a center axis of the retainer ring.
In one embodiment one or more inwardly bent preload fingers or tabs engage an outer surface of the connector body upon assembly. These fingers collapse inwardly as the retainer ring is inserted into the electrical box and spring outwardly once the tabs have passed through the box wall. These fingers function to bias the ring into engagement with the perimeter of the electrical box and provide some degree of improved electrical continuity.
An embodiment of the present invention includes a slit ring retainer having an overlap design to provide alignment and prevent tangling of the rings prior to assembly. The slot may be positioned near one end of the split ring to minimize forces needed to remove the ring from the connector body.
An object of the present invention is the provision of an outer retainer ring having a shoulder structure at its trailing end adapted to engage the perimeter of the knock-out hole of the electrical box. The shoulder structure provides a degree of pull-out resistance for the connector assembly.
The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention.
For a more complete understanding of the present invention, reference is now made to the following descriptions taken in conjunction with the accompanying drawing, in which:
Referring to the drawings,
Connector body 20 is preferably formed of metallic or non-metallic material. For example, connector body 20 may be made of zinc or other suitable metallic alloys or a non-metallic plastic or resin material.
Intermediate the connector body 20, in the illustrated embodiment between the inlet end portion 21 and outlet end portion 22, there is provided radially outwardly extending flange 26 which functions as a stop to limit the degree to which connector body 20 may be inserted through the knock-out hole 16 of junction box 12. In the illustrated embodiment, stop flange 26 is unbroken, while in alternative embodiments stop flange 26 may comprise disjointed or separated elements encircling connector body 20 and together functioning to limit the degree to which connector body 20 may be inserted into a junction box 12.
Retainer ring 30 is preferably split and includes a slot opening 50. Slot opening 50 is adapted to receive a tool, such as a blade of a screwdriver. Slot 50 is preferably located near one end of the split retainer ring 30. Slot 50 is adapted to receive a common tool, such as a screwdriver, to facilitate removal of the retainer ring 30 from inside the electrical box. In the illustrated embodiment, the slot 50 is aligned generally perpendicular to a center axis of the retainer ring 30. Slot 50 is preferably positioned closer to the outlet end portion 22 of the connector body than the stop flange 26. Slot 50 is preferably positioned a distance, D1 (shown in
Retainer ring 30 includes a plurality of inwardly directed finger-like extensions or tabs 40. Tabs 40 are inwardly bent and are sized to operatively engage an outer surface 42 of the connector assembly 10. Tabs 40 are shown as generally unbent along their lengths. In alternative embodiments, the tabs 40 may be bent, curved, or otherwise deformed along the length of tab 40. Tabs 40 collapse inwardly as the retainer ring 30 is inserted into the electrical box and spring outwardly once the tabs 40 have passed through the box wall. These tabs 40 function to bias the ring 30 into engagement with the perimeter of the electrical box and provide some degree of improved electrical continuity.
Retainer ring 30 is held on the outlet end portion 22 of the connector body between lip 24 and stop flange 26. As described herein, the retainer ring 30 may be released from the connector body using a tool such as a screwdriver. Retainer ring 30 is preferably of a spring-type steel.
Retainer ring 30 includes a shoulder structure 60 at its trailing end adapted to engage the perimeter of the knock-out hole of the electrical box. Shoulder structure 60 is defined by a height, H1. In the preferred embodiment height, H1, is approximately equal to a thickness of the retainer ring 30. Shoulder structure 60 is illustrated to encircle the perimeter of the retainer ring. In alternative embodiments shoulder structure 60 may extend around only a portion of the outer perimeter of the retainer ring 30 and may comprise separated sections rather than a continuous shoulder as illustrated. The shoulder structure 60 provides a degree of pull-out resistance for the connector assembly. Upon installation, the wall of the electrical box is held between the forward edge of the shoulder structure 60 and stop flange 26.
During assembly of connector assembly 10, the retainer ring 30 is deformed and seated between stop flange 26 and front lip 24. Tabs 40 function to center the retainer ring 30 around the outlet end portion 22 of connector body 20.
During installation of the connector assembly 10, the retainer ring 30 and outlet end portion 22 are inserted into a hole of the electrical box. The retainer ring 30 is slightly deformed upon insertion into the hole. Once the enlarged portion of the retainer ring 30 passes into the electrical box, the flange structure is biased into engagement with the wall of the electrical box. As a result, the electrical box wall is held between the stop flange 26 of the connector body 20 and the shoulder structure 60 on the retainer ring 30. Shoulder structure 60 is defined by a relatively abrupt transition in the wall of the retainer ring 30.
Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.
This application claims the benefit of U.S. Provisional Application No. 61/307,626 filed Feb. 24, 2010, and incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61307626 | Feb 2010 | US |
