The present invention relates generally to electrical terminals, in particular to an electrical terminal assembly having environmental sealing, retention and electrically insulative features.
A wide variety of devices utilize electrical terminals to provide an interface point for electrical power and signals provided to (or from) the devices. When such devices are installed or operated in adverse environmental conditions it is desirable to seal the electrical terminals in some manner to deter the ingress of moisture and contaminants into the interior portions of the devices.
Electrical terminals are also frequently utilized in devices having compact construction and/or a housing enclosure with complex packaging requirements. In such situations electrically conductive portions of the terminals are often at risk of contacting a housing or enclosure of the device. When the housing or enclosure is electrically conductive this can result in an electrical short-circuit or other failure condition. Accordingly, relatively complex and labor-intensive electrical insulation arrangements are often required.
Further, electrical terminals may be utilized in environments and in applications where maintaining a stable and stationary positioning of the terminals is desired. Retention of the terminals in a manner that prevents rotation relative to the device housing allows for quick and easy attachment of threaded environmental seals. In addition, retention and stationary positioning of the terminals relative to the housing provides a more secure contact with the corresponding electrical connectors for the terminals to maintain electrical communication with the connectors. In such applications it is desirable to secure the terminals in place relative to an adjacent housing or enclosure to prevent rotation along their longitudinal axes and to prevent other undesirable repositioning, while also allowing for their quick and easy removal and replacement. Accordingly, there is a need for a way to efficiently and cost-effectively provide environmental sealing, secure retention and electrically insulative features for electrical terminals.
An electrical terminal assembly is disclosed according to an embodiment of the present invention. The electrical terminal assembly includes one or more terminals, terminal seals and terminal retainers. The terminal seals deter the ingress of moisture and contaminants into a housing or enclosure to which the terminals are mounted. The terminal retainers securely engage the terminal heads and act to deter rotation and repositioning of the terminals while providing electrical insulation of the terminals from the housing.
In one embodiment the disclosed invention includes an electrical terminal assembly including a terminal and a terminal seal. The terminal has a head and a shank, and the shank is configured to be received by a structure having an aperture. The terminal seal is configured to receive and engage the shank, and further configured to engage the structure proximate the aperture. The terminal seal cooperates with the shank and the structure to resist ingress of contaminants into the aperture.
In one embodiment the disclosed invention includes an electrical terminal assembly including a terminal retainer. The terminal retainer is configured to receive and selectably engage a head of a terminal. The terminal retainer is further configured to electrically insulate the head of the terminal and to deter rotation of the terminal without the need for additional tools.
In another embodiment the disclosed invention includes an electrical terminal assembly including at least one terminal, at least one terminal seal, and a terminal retainer. The terminal has a head and a shank, and the shank is configured to be received by a structure having an aperture. The resilient terminal seal is configured to receive and snuggly engage the shank, and the shank is configured to engage the structure proximate the aperture. The terminal seal cooperates with the shank and the structure to resist ingress of contaminants into the aperture. The terminal retainer is configured to receive and captively engage the head of the terminal and to electrically insulate the head from the housing. The terminal retainer is further configured to secure the terminal against rotation.
In a further embodiment the disclosed invention includes a method for assembling an electrical terminal assembly. The method includes the step of obtaining at least one terminal, at least one terminal seal and a terminal retainer. The terminal has a head and a shank, and the shank is configured to be received by an aperture of a structure. The method includes inserting the shank through the aperture of the structure and into the at least one terminal seal. The terminal seal is configured to receive and snuggly engage the shank. The method includes positioning the at least one terminal seal to engage the shank and the structure proximate the aperture. The method includes the terminal seal cooperating with the shank and the structure to resist ingress of contaminants into the aperture. The terminal retainer is configured to receive and engage the head of the terminal and to electrically insulate the head from the housing. The method includes inserting the head of the terminal into the terminal retainer, and the terminal retainer electrically insulating the head from the housing and preventing rotation of the terminal during use without the need of additional tools.
Further features of the inventive embodiments will become apparent to those skilled in the art to which the embodiments relate from reading the specification and claims with reference to the accompanying drawings, in which:
In the discussion that follows, like reference numerals are used to refer to like structures and elements in the various figures.
The general arrangement of an electrical terminal assembly 10 is shown in
Terminals 12 may be any type of electrical connector that is suitable for a particular device 20. Terminal 12 is normally electrically conductive for electrical communication with an interior portion of device 20. In the embodiment of
With reference to
Terminal seals 14 may be made from separate components and assembled together. As a non-limiting example, internally threaded portion 40 may be formed as a separate nut or threaded insert made of metal or other suitable durable material that can be molded together within seal head portion 38 using plastic or some other suitable corrosion-resistant material to form the terminal seal 14. Alternatively, terminal seals 14 may be fabricated as a single or unitary piece from a suitable electrically insulative material, such as a plastic or composite. Terminal seals 14 may further be made from assembled metal pieces or from a unitary metal piece, and optionally finished with either a conductive or non-conductive material. Terminal seals 14 may be provided in one or more predetermined colors, such as red to indicate positive electrical polarity and black to indicate negative electrical polarity in the case of direct current (DC) electrical power terminals.
With reference now to
With reference again to
The shank portion 24 of terminals 12 include a tip 74 configured for electrical communication with a corresponding connector (not shown) exterior to the device 20. In one embodiment, an electrical conductor such as printed wiring board 76 (
Electrical terminal assembly 10 may be assembled to housing 18 by inserting tips 74 of terminals 12 through printed wiring board 76, nuts 72 and bores 64 of the housing. In one embodiment, device 20 further includes a gasket 77 to seal perimeter openings of housing 18 (see
A terminal seal 14 is then threaded onto the shank portion 24 of each terminal 12. Tips 74 of the shank portions 24 are inserted through the sleeve 46 of a corresponding terminal seal 14 such that external threads 26 of the terminals engage the internal threads 42 of the terminal seals. Terminal seals 14 are threaded onto the corresponding terminals 12 until the terminal seals are secured against surface 68 of housing 18. As terminal seals 14 are threaded onto terminals 12, lips 48 of the terminal seals sealingly engage corresponding grooves 78 formed in surface 68 and sleeves 46 are received within apertures 66 of bores 64 (see
Terminal seals 14 are preferably threaded onto the corresponding terminals 12 to a point where the shoulder surfaces 28 of terminal head portions 22 are adjacent to or engage mechanically and/or electrically with corresponding printed wiring board 76. Once terminal seals 14 are thus installed, tips 74 remain exposed on the exterior of device 20, ready for coupling and electrical communication with corresponding connectors (not shown) exterior to the device 20. After terminal seals 14 are installed, the rear side 56 of the terminal retainer 16 may be positioned adjacent or against an internal surface of housing 18, such as heat sink 80, for example (see
Optionally, a sealing gasket 82 may be placed intermediate to surface 68 and the rear surface 50 of each of terminal seals 14 to provide an environmental seal for the terminal assembly 10. Gasket 82 may be made from any suitable compressible materials such as, without limitation, plastic and elastomerics such as natural and synthetic rubber. Gasket 82 may be made as a formed piece and attached to rear surface 50 of terminal seal 14, to surface 68, or both. Alternatively, gasket 82 may be left unattached and be captively retained between surface 68 and rear surface 50. In an alternative embodiment gasket 82 may be a generally solid disk having cross-slits (
In the assembled state terminal retainer 16 secures terminals 12 against rotational movement during attachment of the corresponding external connectors (not shown) to tips 74. In addition, terminal retainer 16 maintains position of terminals 12 (and thus the terminal seals 14) to deter loosening or repositioning of the terminals during use of the device, especially in applications subject to vibration. Furthermore, in the assembled state terminal assembly 10 provides an electrical termination point that resists the ingress of contaminants into housing 18.
With reference now to
Referring again to
A reinforcing ridge 108 may be formed on peripheral side 92 proximate to either of first and second cavities 94, 96 to provide structural reinforcement. Reinforcing ridge 108 may be formed as an extension of peripheral side 92 along the second portion 100. Reinforcing ridge 108 may be formed with a varying thickness that tapers out from a minimum at first corners 104 of receptacles 86 to a maximum at a peak 110 proximate second corners 106 of the receptacles. Reinforcing ridge 108 may be made integral with peripheral side 92 or may be made separately and attached thereto. Reinforcing ridge 108 may include a front side 112 and an opposing rear side 114. Front side 112 and/or rear side 114 may include one or more front channels 116 and/or rear channels 118, respectively, formed therein. Front channels 116 and rear channels 118 may be formed as recesses, or alternatively, may be formed as protrusions.
Recesses 84 may further include one or more notches 120 which may be disposed at one or more of the first corners 104 and the second corners 106 for a snug fit. Notches 120 are configured to allow selectable physical expansion of receptacles 86 during insertion onto terminal head portions 22. Referring to
With reference now to
Gasket 247 may be made from any suitable compressible materials such as, without limitation, plastic and elastomerics such as natural and synthetic rubber or polyethylene terephthalate (PET). Gasket 247 may be made as a formed piece and attached to internally threaded portion 240 and/or sleeve 246 and/or recess 249. Alternatively, gasket 82 may be left unattached and held captively between an interior facing portion of sleeve 246 and the external threads 26 of terminal 12. Although shown as a disk-shaped gasket, gasket 247 may be in the shape of an O-ring. In an alternative embodiment gasket 247 may be a generally solid disk having cross-slits. In yet another alternative embodiment gasket 247 may be applied in a liquid, gel or foam form as a form-in-place seal, co-molded in place.
Terminal retainers 16, 84 may be made from any suitable material, such as plastic or composites. Preferably, terminal retainers 16, 84 are made from an electrically non-conductive material, although electrically conductive substrates that are coated or plated with a suitable insulative layer may be used within the scope of the invention. Alternatively, recesses 60, 88 may include metal or other durable material that is molded together with plastic or some other suitable non-conductive material to form terminal retainers 16, 84.
Although two terminals 12 are shown and described herein, a greater or lesser number of terminals are possible within the scope of the invention. Although two receptacles 52, 86 for each terminal retainer 16, 84, respectively, are shown and described herein, a greater or lesser number of receptacles are possible within the scope of the invention. In addition, terminal retainers 16, 84 may optionally be selectably or permanently coupled to an adjacent structure to deter rotational movement of a corresponding terminal 12, for example if a single terminal is provided. Optionally, a material including adhesive or tacky properties may be further used to assist in joining the terminal retainer 16, 84 to the terminal head portions 22. Optionally, some or all of the features of the alternative embodiment terminal retainer 84 of
While the foregoing description relates to the use of the electrical terminal assembly in connection with a housing structure of a device, one skilled in the art will readily recognize that the electrical terminal assembly may be used to advantage in connection with any suitable structure. For example, the electrical terminal assembly may be assembled to a panel structure.
While this invention has been shown and described with respect to a detailed embodiment thereof, it will be understood by those skilled in the art that changes in form and detail thereof may be made without departing from the scope of the claims of the invention.
This application claims priority to U.S. provisional application 61/974,550, filed Apr. 3, 2014, and U.S. provisional application 62/014,949, filed Jun. 20, 2014, the entire contents of each application being incorporated by reference herein.
Number | Date | Country | |
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61974550 | Apr 2014 | US | |
62014949 | Jun 2014 | US |