Electrical contacts with compliant tail portions are well-known. FIG. 1 depicts a prior-art press-fit electrical contact 100 having body portion 105 and compliant tail portion 110 that extends from body portion 105. The tail portion 110 may include a straight single beam portion 180 that extends from the body portion 105. Each of two curved portions 115, 120 may extend from the beam portion 180. Inner edges 185, 190 of the curved portions 115, 120 may define a slot, or “eye of the needle” 140. The tail portion 110 may define a distal portion 145, which may include a lead-in tip 150.
The curved portions 115, 120 may define opposing contact points 125, 130, respectively. The contact 100 may be inserted into a plated through-hole 132 in a direction of insertion 112. The through-hole 132 may extend through a substrate 122, which may be a printed circuit board (PCB) for example. The contact points 125, 130 may define the maximum width W of the tail portion 110, as measured transverse to the direction of insertion 112. The diameter D of the through-hole 132 may be less than the width W defined between the contact points 125, 130. Consequently, as the tail portion 110 is inserted into the through-hole 132, the sidewalls 133, 134 of the through-hole 132 may exert a compressive force on the tail portion 110 at the contact points 125, 130, thereby compressing the curved portions 115, 120 into the slot 140. The opposing forces at the contact points 125, 130 may define both the insertion force necessary to fully seat the contact in the through-hole, and the retention force necessary to move the contact back out of the through-hole.
With the miniaturization of electronic devices, it is often desirable to reduce the overall size of an electrical connector by reducing the size of its electrical contacts. However, as the contacts become smaller, they may become less physically robust. Thus, the insertion force needed to press fit the electrical contacts into the plated through-holes may be enough to cause the electrical contacts to bend or break.
Also, the slot 140 of the tail portion 110 is typically punched out via die tooling. Given the small size of the tail portion 110 and the slot 104, the die tooling used may need to be small and, consequently, fragile. Such die tooling may be susceptible to damage even after a short period of use. Consequently, the die tooling may need to be repaired or replaced frequently. This may lead to manufacturing delays and/or higher manufacturing costs.
USPTO Backgrounds
USPTO Backgrounds