Background of the Invention
1. Field of the Invention
This invention relates to contacts for use with insertable circuit boards, and more particularly to contacts having contact points which can be adjusted longitudinally within their housing.
2. Description of the Prior Art
In known devices of this type, a resilient lyre-shaped contact is secured within the cavity of a housing by engagement of the contact with a boss within the cavity. To adjust the longitudinal position of the contact, the entire contact member is moved longitudinally within the cavity and is secured to selected bosses which are spaced along the length of the cavity.
Such known devices cannot be used with both single-faced and double-faced printed circuit boards because of their lyre-shaped construction which is formed to optimize contact engagement on both sides of the board simultaneously by a single contact. Further, they require complex and expensive housings in order to provide cavities with suitable securing bosses. Additionally, the introduction and removal of the contact members by deformation of the body of the contact causes the connector to wear and limits the number of contact changes and adjustments in longitudinal position. Also, since the entire contact is moved within its housing, the position of the conductor joining end is changed each time the contact position is changed.
Summary of the Invention
It is an object of the invention to provide an improved and economical two-position contact member. According to the invention, one end of the contact member has a flexible loop with two contact portions. One contact portion is on one side of the axis of the contact member, and the other contact position is on the other side of the axis. The two contact portions are spaced longitudinally from each other. Means extending from the contact member are provided to position and secure the contact member within a cavity having a pair of opposed bosses on opposite walls of the cavity. The contact member can be secured in the housing in one of two selected positions by rotating it 180.degree. about its longitudinal axis. A different one of the two contact portions is engagable with the printed circuit card for each position.
Thus, two different contact positions can be obtained without changing the longitudinal position of the wiring end of the contact member. Further, the insertion and removal of a contact does not exert any excess stress upon the body of the contact member, thus permitting an unlimited number of contact replacements or contact position changes without damaging the contact member. Additionally, the housing can be readily formed by a simple molding procedure and is therefore less expensive to fabricate than prior art housings requiring relatively complex cavity configuration.
The contact member according to the invention can be utilized in a housing having a single cavity to contact one side of a printed circuit card, or two contact members can be utilized in a housing having a pair of contact cavities to contact both faces of a double-faced printed circuit card.
Brief Description of the Drawings
The invention will now be described in detail with reference to the accompanaying drawings representing preferred embodiments of the contact member. In the drawings:
FIG. 1 is a side view of a section of a housing showing a contact member positioned in a cavity;
FIG. 2 is a front view of a contact member; and
FIG. 3 is a side view of two-sectioned housings showing the contact member in two different preselected positions.
Description of the Preferred Embodiments
In the preferred embodiment, shown in FIGS. 1-3, a two-position contact member for either a single or double-ffaced printed circuit card is obtained in one piece by stamping and bending a conductive material having elastic properties which permit the forming of a spring bend or loop 1 with two contact portions 2, 3 of different longitudinal spacing. The elastic deformability of the contact portions is increased by using a strip of metal which is thinner in the loop portion than in the shank portion. As shown in FIG. 2, a slot 4 is cut longitudinally into each of the contact portions 2, 3 to provide a two-point electrical contact for each contact portion.
The contact member is lodged in the seating cavity 5 of the connector housing by inserting it from the front face of the connector housing (upper end
A spring catch 6 (securing means) is provided to engage with a boss 7 or a boss 8 in the seating cavity. It includes a lug 9 preventing any downward movement and a lug 10 preventing any upward movement. By means of this catch, the contact member is thus secured in the longitudinal direction.
Tabs 11 and 12 (positioning means) provide correct guidance of the contact member during its introduction into the seating cavity and prevent its rotation with respect to the seating cavity. At the same time, the tabs 11 and 12 insure the correct positioning of the wiring end 13 of the contact member.
A part 14 of the seating cavity serves to support the tab 11 and secures the contact member with respect to rotation when the contact member is in a preselected position with contact portion 3 in position for engagement with one side of a printed circuit card. as shown in the right hand side of FIG. 3.
Changing the position of the active contact portion is done as follows: An appropriate tool is introduced into the seating cavity 5 in which a contact member is in place. The spring catch 6 of the contact is pinched to disengage it from the boss 7 (FIG. 1). While holding the spring catch 6 against the rigid shank 15 of the contact member from which it branches, the contact member can be easily extracted through the front (upper) face of the connector housing. Once the contact member is out of the seating cavity it is turned 180.degree. and then reinserted into the seating cavity 5 until the spring catch 6 engages with the boss 8 (FIG. 3). The lower contact portion 2 is thus replaced by the higher contact portion 3 which is engagable with the printed circuit card as shown in FIG. 3.
The direction of introduction of the dismounting tool as well as the side of extraction of the contact member are given only by way of example and are in no way limiting.
The different component parts have been described as being all in one piece but they could, of course, be assembled from components.
From the foregoing, it can be readily realized that this invention can assume various embodiments. Thus, it is to be understood that the invention is not limited to the specific embodiments described herein, but is to be limited only by the appended claims.