The invention relates to receptacle contacts, and more particularly to receptacle contacts with multiple contact areas.
Currently electrical contacts or wire contacts are used to terminate a wire. Wire contacts require a strong mechanical means of attaching to the wire to create a permanent termination and a means to mate to a mating contact to form an electrical connection. For example, a wire contact may have a crimp end for terminating the wire and a male or female mating end for a mating contact. Some contacts have been developed from metal strips or pre-plated metal strips, which are stamped and then folded or formed into the appropriate shape. These contacts have a generally box shaped mating end for mating to a contact having a pin or blade type mating end. Contacts with a boxed shaped mating end have external size and shape requirements to fit into a cavity of a connector and an internal design for providing the mechanical and electrical connection means for receiving and holding the pin or blade contact of the mating contact. In current contacts having generally boxed shaped mating ends, a contact or compliant beam may be the means to receive and hold the mating pin contact.
However, known connectors typically contact and mate the pin or mating contact at up to two areas. This can result in a lack of sufficient physical contact that reduces the reliability of the electrical connection and renders the connector susceptible to reduction or loss of connection. Further, vibration or other motion or movement may result in a loss of connection.
In addition, some known connectors have contact beams that have a high spring force, which decreases the ability to control the normal force applied by the contact beam, increasing the mating force of the connector, and increasing tolerance sensitivity. Other connector problems may arise from having the contact beam exposed to the mating pin, leaving the contact beam unprotected from damage from external factors.
What is needed is a contact and method of insertion that satisfies one or more of these needs or provides other advantageous features. Other features and advantages will be made apparent from the present specification. The teachings disclosed extend to those embodiments that fall within the scope of the claims, regardless of whether they accomplish one or more of the aforementioned needs.
An exemplary embodiment is directed to a receptacle contact for receipt of a mating contact therein. The receptacle contact has a contact portion with side walls, each of the side walls has an opening provide therein. A resilient contact arm extends between the side walls. The resilient contact arm has a fixed end and a distal end with at least one first contact area positioned proximate thereto. Projections extend from the resilient contact arm and extend through the openings of the side walls. A weak area is provided on the resilient contact arm, the weak area positioned between the fixed end and the projections. The weak area having a second contact area positioned proximate thereto. The projections engage a top wall of the opening of the sidewalls as the mating contact is inserted into the receptacle contact, causing the second contact area proximate the weak area to move into engagement with the mating contact, thereby providing multiple areas of contact between the resilient contact arm and the mating contact to provide a stable and reliable electrical connection therebetween.
An exemplary embodiment is directed to a receptacle contact for receipt of a mating contact therein. The receptacle contact has side walls, each of the side walls has an opening provide therein. A first resilient contact arm extends between the side walls. The first resilient contact arm has a fixed end and a free end with at least one first contact area positioned proximate to the free end. Projections extend from the first resilient contact arm, the projections extend through the openings of the side walls. A weak area is provided on the first resilient contact arm, the weak area positioned between the fixed end of the first resilient contact arm and the projections of the first resilient contact arm. The weak area having a second contact area positioned proximate thereto. A second resilient contact arm extends between the side walls. The second resilient contact arm has a fixed end and a free end. A third contact area is positioned proximate to the free end of the second resilient contact arm. The third contact area is positioned laterally between the at least one first contact area of the first resilient contact arm and the weak area of the first resilient contact arm. The projections engage a wall of the opening as the mating contact is inserted into the receptacle contact, causing the second contact area proximate the weak area to move into engagement with the mating contact, thereby providing multiple areas of contact between the first and second resilient contact arms and the mating contact to provide a stable and reliable electrical connection therebetween.
An exemplary method is directed to a method of inserting a mating contact into a receptacle contact, the receptacle contact having side walls and at least one resilient contact arm, the method comprising: engaging the at least one resilient contact arm with the mating contact; moving the at least one resilient contact arm from an unstressed position; engaging a wall of an opening with at least one projection of the at least one resilient contact arm to prevent further movement of a weak area of the at least one resilient contact arm; and moving a portion of the at least one resilient contact arm about the weak area of the at least one resilient contact arm after the at least one projection has engaged the wall of the opening.
Other features and advantages of the present invention will be apparent from the following more detailed description of the preferred embodiment, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention.
Wherever possible, like reference numerals are used to refer to like elements throughout the application.
In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of various embodiments. However, those skilled in the art will understand that the embodiments may be practiced without these specific details, that the embodiments are not limited to the depicted embodiments, and that the embodiments may be practiced in a variety of alternative embodiments. In other instances, well known methods, procedures, and components have not been described in detail.
Further, various operations may be described as multiple discrete steps performed in a manner that is helpful for understanding the embodiments. However, the order of description should not be construed as to imply that these operations need be performed in the order they are presented, or that they are even order-dependent. Moreover, repeated usage of the phrase “in an embodiment” does not necessarily refer to the same embodiment, although it may. Lastly, the terms “comprising,” “including,” “having,” and the like, as used in the present application, are intended to be synonymous unless otherwise indicated.
The disclosure relates to a receptacle contact and method of mechanically and electrically engaging a mating pin contact with the receptacle contact.
The exemplary embodiment of
In the exemplary embodiment shown, the crimp portion 22 has a rear insulation member 26 and a conductor member 28. The insulation member 26 and conductor member 28 respectively engage the insulation and the conductor of a wire in a known manner. While a crimped connection is shown, the portion 22 may connect to a respective wire using other known technology, such as, but not limited to, insulation displacement technology. The transition portion 24 extends between the mating portion 20 and the crimp portion 22.
The mating portion 20 includes a box-shaped contact portion 30 for accepting a respective mating contact or mating pin contact 32 (
Side wall 38 extends between and is integrally attached to the bottom wall 34 and the top wall 36. Side wall 40, as best shown in
Each side wall 38, 40 has an opening 50 which extends therethrough. In the exemplary embodiment shown, the openings 50 are proximately aligned with the locking projection 42; however other configurations may be used without departing from the scope of the invention.
With reference to
Referring to
As best shown in
An overstress projection 67 may also be provided on the bottom wall 34. The overstress projection 67 is provided between the support device 66 and the distal end 56 of the spring arm 52. The overstress projection 67 is provided to cooperate with the spring arm 52 as the mating pin contact 32 is inserted into the receptacle contact 10. As the spring arm 52 is deflected toward the bottom wall 34, the overstress projection 67 may engage the spring arm 52 to prevent further movement of the spring arm 52 toward the bottom wall 34, thereby preventing the spring arm 52 from taking a permanent set. The position and size of the overstress protection 67 may be directly related to the amount of deflection required for the spring arm 52 to take a permanent set.
In one embodiment, the bottom wall 34 has a support arm 64 and no overstress projection 67. In another embodiment, the bottom wall 34 has an overstress projection 67 but no support arm 64. In another embodiment, the bottom wall 34 has both an overstress projection 67 and support arm 64.
A support device or detent 68 may be provided on the top wall 36. The support device 68 is provided proximate to, but spaced from the 180 degree bend of the spring arm 54. The spring arm 54 cooperates with the support device 68 to allow the forces applied to the spring arm 54 during the insertion of the mating pin to be transferred through the support device 68 to the top wall 36. No or essentially no force is generated by the 180 degree bend, thereby generating no stress in the 180 degree bend. The shape and spacing of the support device 68 can be varied depending upon the structure of the spring arm 54 and the contact portion 30.
As previously described, spring arm 54 has contact areas 62 provided proximate the distal end 58 thereof. In the embodiment shown, as best shown in
As is shown in
As the insertion of the pin contact 32 continues to the position shown in
With the pin contact 32 engaged at both the contact areas 62 and contact areas 77, further movement of the spring arm 54 is limited. Therefore, any further displacement of the resilient contact arms 52, 54 required as the mating pin contact 32 is inserted is facilitated by the spring arm 52 and support arm 64.
During insertion of the mating pin contact 32, the mating pin contact 32 contacts the weak area 76 and the contact areas 77 of the spring arm 54, which provide a “lifting” or moving force. As the contact areas 77 are spaced from the fixed end of the spring arm 54 and the contact areas 62 are positioned proximate the distal end 58 of the spring arm 54, the normal force required to move the spring arm 54 is reduced. The mating force or the force required to deflect the spring arm 54 is a cubic function of the distance or length from the bend to the respective contact areas. As insertion continues and the lifting of the spring arm 54 is substantially complete, the contact areas 62 are contacted by mating pin contact 32. As the spring arm 54 almost fully deflected or “lifted” by the weak area 76 and contact areas 77, the contact areas 62 engage the mating pin contact 32 with a low mating force and a shallow mating angle, thereby allowing the contact areas 62 to be placed in electrical contact with the mating pin contact 32 with minimal wear on the contact areas 62 and the plating thereof.
In the fully inserted position, the contact areas 60, 62 and the contact areas 77 are all provided in electrical and mechanical contact with the mating pin contact 32. The multiple areas of contact allow the receptacle contact 10 to be used in applications in which higher current levels, such as, but not limited to, 15 to 20 or more amps are required.
As best shown in
In addition, as the contact areas 77, contact area 60 and contact areas 62 are laterally offset from each other, the receptacle contact 10 provides multiple contact areas even if the mating pin contact 32 is bent, causing the pin contact 32 to not engage a particular area. In addition, the multiple contact areas resist twisting or misalignment of the mating pin contact 32.
In one embodiment, the resilient contact arms 52, 54 are configured such that all contact areas of the spring arm 54 generate an equal and opposite force to resist the force generated by spring arm 52. However, the configuration of the resilient contact arms 52, 54 and support arm 64 may be varied to allow the contact areas to have varied forces associated therewith. In particular, the positioning of the contact areas 60, 62 and the contact areas 77 can alter the force applied by each contact area.
As the contact areas 77 and contact areas 62 are transversely offset relative to the path of insertion of the mating pin contact 32, the plating wear on the mating pin contact 32 at any particular area is minimized, as the wear is distributed over different areas.
As is shown in the
The configuration of the resilient contact arms 52, 54 and the use of multiple contact areas allows for a lower normal force during mating and unmating of the mating contact pin 32 from the receptacle contact 10. This allows the contact pin 32 and receptacle contact 10 to be more durable over numerous cycles, as there is less plating wear due to the lower mating or normal forces. The number of contact areas also allows the receptacle contact 10 to be used at higher current levels, as the number of contact areas allows the extreme heat associated with the high current levels to be dispersed, thereby preventing welding of the contact asperities.
While the above has been shown and described with respect to a mating pin contact, the invention is not so limited and may include any configuration of a mating electrical contact that is insertable into the receptacle contact 10, such as a tab, wire, plug or other electrical contact device.
While the written description has referred to a preferred embodiment, it will be understood by those skilled in the art that various changes and modifications may be made and equivalents may be substituted for elements thereof without departing from the patentable scope as defined by the claims. Therefore, it is intended that the patentable scope not be limited to the particular embodiments disclosed as the best mode contemplated, but rather other embodiments are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
This application claims the priority of U.S. provisional patent application No. 61/496,086 filed Jun. 13, 2011, incorporated herein by reference in its entirety.
Number | Date | Country | |
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61496086 | Jun 2011 | US |