Telescoping spring probe having separate wiper contact member

A miniature low resistance telescoping spring probe comprising:

• telescoping tubular housing and inner plunger both being elongated and of an electrically conductive material, said plunger comprising a probe head external to said housing;
• engaged and concentric inner wall on said housing and outer wall on said plunger providing a sliding electrical connection and a bearing therebetween;
• a coil compression spring urging said housing and plunger in longitudinally opposite directions;
• and
• means for establishing a substantially constant low electrical resistance connection between said housing and plunger during the entire telescoping cycle thereof, comprising
• a separate low electrical resistance wiper spring member affixed to said plunger,
• a substantially constant low electrical resistance connection between said wiper spring member and plunger,
• said wiper spring member comprising at least one longitudinally extending leg spring loaded outwardly into engagement with said inside wall, and
• a bearing surface on said leg in engagement with and contoured to match the shape of the transverse cross-section of said inside wall and thereby providing a substantially constant low electrical resistance connection between said wiper spring member and inside wall during telescoping movement.

A miniature low resistance spring probe comprising:

• telescoping tubular housing and inner plunger both being elongated and of an electrically conductive material;
• said plunger comprising a probe head external to said housing;
• engaged and concentric inner walll on said housing and outer wall on said plunger providing a sliding electrical connection and a bearing therebetween;
• means for establishing a substantially constant low resistance electrical connection between said housing and probe during the entire telescoping cycle thereof comprising
• a stud, formed from said plunger, which is longitudinally extending away from an end of said plunger inside of said housing,
• a separate wiper spring member having an end with an opening therein which forms an interference fit with said stud to thereby provide a low resistance electrical connection and prevent relative transverse movement between said plunger and wiper spring member, and
• said wiper spring member comprising a leg extending longitudinally from the end thereof and spring loaded outwardly into engagement with said inside wall to thereby provide low resistance electrical contact with the inside wall throughout the telescoping cycle;
• and
• a coil compression spring acting between the housing and the inside end of said plunger through the end of said wiper spring member urging said housing and plunger in longitudinally opposite directions and capturing and securing the end of the wiper spring member in engagement with the plunger.

A miniature low resistance spring probe comprising:

• telescoping tubular housing and inner plunger both being elongated and of an electrically conductive material;
• said plunger comprising a probe head external to said housing;
• engaged and concentric inner wall on said housing and outer wall on said plunger providing a sliding electrical connection and a bearing therebetween;
• a coil compression spring urging said housing and plunger in longitudinally opposite directions;
• and
• means for establishing a substantially constant low resistance electrical connection between said housing and probe during the entire telescoping cycle thereof, comprising
• a separate low electrical resistance wiper spring member affixed to said plunger,
• a substantially constant low resistance electrical connection between said wiper spring member and plunger,
• said wiper spring member comprising an elongated leg extending longitudinally along said plunger and comprising a bearing portion spring loaded by the leg into low electrical resistance contact with said inside wall and an inwardly extending portion on each side of said bearing portion which engages said plunger and stabilizes said leg.