1. Field of the Invention
The present invention relates in general to a push-in electrical connector for wires and, in particular, to a disconnect for repeatable connection of multiple wires of either single- or multi-thread. More particularly, the present invention relates to a disconnect that provides electrical connection using a male and female engagement with enhanced mechanical contact pressure.
2. Description of the Related Art
Push-in wire connectors are useful for connecting multiple wires electrically together in applications that include, for example, providing utility power grid for homes and offices, etc. When equipped with a repeatably engage and disengage connector design, such electrical disconnect is greatly useful in applications such as typically used in the ballast connection for fluorescent light fixture per the requirement of Section 410.73 of the National Electrical Code.
U.S. Pat. No. 7,887,353 to Bethurum et al. discloses an electrical disconnect with push-in connector design. This disconnect relies on a dimple formed on the male and female contacts to facilitate electrical contact between its separable connectors. However, this configuration does not provide sufficiently good electrical connection between its male and female contacts due to insufficient mechanical contact pressure to warrant good disconnect characteristics, namely, good current rating, which affects directly the disconnect's safety characteristics.
The disconnect according to Bethurum et al. has a pair of dimples formed on the male and female contacts. This pair of corresponding dimples are normally put to a natural relax condition as the housings of the disconnect are fully engaged. In other words, the dimples contribute their mechanical stress only in the process of disconnect installation. After this transient state, the dimples contributes nothing to the improvement of electrical contact characteristics of the disconnect.
It is therefore an object of the present invention to provide a disconnect for electrically connecting wire pairs that has increased mechanical grip between contacting connectors for improved electrical conductivity.
It is another object of the present invention to provide a disconnect for electrically connecting wire pairs that has increased mechanical grip between contacting connectors for improved safety.
The present invention achieves the above and other objects by providing a disconnect (10) for electrically connecting wire pairs according to a preferred embodiment of the present invention. The disconnect has a pair of male and female connector housings as well as a pair of male and female connectors. The male connector housing (102) has a male connector engagement socket (103) and the female connector housing (202) has a female connector engagement socket (203) for sleeve-engagement with the male connector engagement socket (103). The male connector (120) is housed inside the male connector housing (102) and has a male connector engagement end (122). The female connector (220) is housed inside the female connector housing (202) and has a female connector engagement end (222). The female connector engagement end (222) has a contact finger (240) and a pressure finger (250) for mechanical gripping engagement with the male connector engagement end (122) when the male and female connector housings (102, 202) are sleeve-engaged and the male connector engagement end (122) is inserted between the contact and pressure fingers (240, 250). In the preferred embodiment of the disconnect of the present invention, contact finger tip (245) of the contact finger (240) and the pressure finger tip (255) of the pressure finger (250) are forced apart from each other by the engagement insertion and are pressed onto inner sidewalls of the female connector engagement socket (203) for increasing the mechanical grip.
The present invention further provides a disconnect wherein the internal space inside the female connector engagement socket (203) has a width that is larger than a distance between the contact finger tip (245) of the contact finger (240) and the pressure finger tip (255) of the pressure finger (250) when the male connector engagement end (122) is not inserted between the contact (240) and pressure finger (250).
The present invention further provides a disconnect wherein the width between finger tips (245, 255) of the two fingers (240, 250) of the female connector (220) is the widest portion of its body along an entire length-wise direction with or without the insertion of the male connector (120).
A first segment of a first wire of a circuit, shown in
Similarly, when assembled, a first segment of 12M of a second wire, connected to the male connector 120, can be electrically connected to its opposite wire segment 12F at the end of the female connector 220, forming a second wire circuit for the application. Note that when properly assembled, as is clearly illustrated in
Connection of wires 11F and 12F with their respective female connectors 220 as well as wires 11M and 12M with respective male connectors 120, as illustrated in the exploded perspective view of
In order for the inventive disconnect 10, when assembled, to ensure a secure and reliable electrical connection between the wire pairs 11M and 11F and between 12M and 12F, there must be a secure and firm electrical contact between the male 120 and female connector 220 of disconnect 10. Meanwhile, it is necessary to also have a secure and firm mechanical engagement between the male connector housing 102 and the female connector housing 202. This secure and firm mechanical engagement of housings ensures the reliable electrical connection.
Equally necessary, the disengagement between male 120 and female connector 220 as well as between the male connector housing 102 and the female connector housing 202 must be easy and convenient. This is necessary for the disconnect 10 to easily facilitate its functionality of electrical disconnection between wire pairs 11M and 11F and between 12M and 12F, a feature as important as providing firm and secure electrical connection.
When the inventive disconnect 10 is assembled, as is illustrated in
Such smooth sliding also allows for the proper alignment of the engagement end 122 of the male connector 120 with respect to the engagement end 222 of the female connector 220 as the two housings are pushed toward each other for the connection assembly of the disconnect 10. This leads to the smooth insertion of the engagement end 122 into the corresponding engagement end 222 when the disconnect 10 is fully assembled as shown in
Each of the male and female connector engagement pairs that facilitates electrical connection for the disconnect 10 as described in
Note that in a preferred embodiment of the present invention, each of both the male 120 and female connector 220 can be made from single piece of metallic material. Preferably, they can be made by press-forming, a highly efficient yet low-cost mass production practice. Preferably, they can be made using phosphor copper, an alloy to provide best electrical connection with proper physical property to provide adequate mechanical strength for the necessary contact pressure between the male and female connectors.
As is illustrated in
Note that in the exemplified embodiment of the present invention the finger 250 has two finger branches 251 and 252 as is illustrated. Ina preferred embodiment of the present invention, the fingers 240 and 250 of the female connector 220 are formed from one single piece of metal via metal work processes such as hydraulic stamping, therefore the formation of the finger branches 251 and 252 for the finger 250.
When assembling to establish electrical connection—such as between wire pairs exemplified in FIG. 1—the two housings, i.e., male connector housing 102 and female connector housing 202, are assembled together, as is illustrated in
This alignment is easily and smoothly possible due to the guided insertion of the engagement socket 203 into the engagement socket 103. The proper alignment allows the male connector engagement end 122 to enter the opening at the female connector engagement end 222 as both housings 102 and 202 are pushed against each other. However, note that although the exemplifying disconnect 10 described herein has the engagement socket 203 of its female connector housing 202 inserted inside the engagement socket 103 of the male connector housing 102, an opposite arrangement is also feasible. For example, alternatively the engagement socket of the male connector housing 102 can be made so that it can be inserted inside the correspondingly-sized opening of the engagement socket of the female connector housing 202.
Note that during normal use such as by an electric technician in the new installation of a fluorescent lamp, the male and female connector housings 102 and 202 of a disconnect 10 would each already has its respective male 120 and female connector 220 installed in place inside. Normally the entire disconnect 10 is presented as an electrical connector system with two separable parts-seen by the user as a pair of connectors in the form of the housings 102 and 202. Wiring for the lamp can be inserted into the two separate male and female housings as suggested in
For reliable electrical connection, the disconnect 10 needs to ensure firm electrical contact between the mating male 120 and female connector 220. One major factor for such a firm contact is a sufficient mechanical contact pressure at the point of contact between the male and female connectors. The key to the achievement of an enhanced mechanical contact pressure between the mated connectors is explained in
As illustrated in
Then, simultaneous reference to
The fact that the width of the engagement socket 203 is smaller than the fingertip distance when there is an insertion constitutes no problem. In fact, this is essential for an enhanced mechanical pressure that the fingers 240 and 250 of the female connector 220 grip onto the inserted engagement end 122 of male connector 120. This is because the metallic nature of the fingers 240 and 250 of the female connector 220 allows for the deformation of themselves so that the fingertip distance is shortened to fit inside the engagement socket 203. It is because of this spring-loaded deformation of fingers 240 and 250 to provide the enhanced gripping mechanical force required for improved electrical contact characteristics.
Thus, with reference to the accompanying drawings, a disconnect 10 for electrically connecting wire pairs according to a preferred embodiment of the present invention would have a pair of male and female connector housings as well as a pair of male and female connectors. The male connector housing 102 has a male connector engagement socket 103 and the female connector housing 202 has a female connector engagement socket 203 for sleeve-engagement with the male connector engagement socket 103.
The male connector 120 is housed inside the male connector housing 102 and has a male connector engagement end 122. The female connector 220 is housed inside the female connector housing 202 and has a female connector engagement end 222. The female connector engagement end 222 has a contact finger 240 and a pressure finger 250 for mechanical gripping engagement with the male connector engagement end 122 when the male and female connector housings 102, 202 are sleeve-engaged and the male connector engagement end 122 is inserted between the contact and pressure fingers 240, 250.
In the preferred embodiment of the disconnect of the present invention, contact finger tip 245 of the contact finger 240 and the pressure finger tip 255 of the pressure finger 250 are forced apart from each other by the engagement insertion and are pressed onto inner sidewalls of the female connector engagement socket 203 for increasing the mechanical grip.
In other words, the internal space inside the female connector engagement socket 203 has a width that is larger than a distance between the contact finger tip 245 of the contact finger 240 and the pressure finger tip 255 of the pressure finger 250 when the male connector engagement end 122 is not inserted between the contact 240 and pressure finger 250.
In a preferred embodiment, the width between finger tips 245, 255 of the two fingers 240, 250 of the female connector 220 is the widest portion of its body along an entire length-wise direction with or without the insertion of the male connector 120.
It is necessary for the metallic male connector 120 to be securedly placed inside its protective housing 102 once it is installed inside.
While the above is a full description of the specific embodiments, various modifications, alternative constructions and equivalents may be used. Therefore, the above description and illustrations should not be taken as limiting the scope of the present invention, which is defined by the appended claims.