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US 4,878,852 AGranted
Circuit tester construction
AssigneePolytronics, Ltd.
InventorsJack E. Bertsch, Harold P. Kopp
Life of this patent
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AssigneePolytronics, Ltd.
InventorsJack E. Bertsch, Harold P. Kopp
Estimating the term…
A ground pin construction for an electrical device having a housing and prongs for insertion into an electrical socket, the housing including a boss having a bore therein for guiding the ground pin between extended and retracted positions, a flexible member attached to the ground pin and movable by a button which protrudes through the housing, cam surfaces on the housing which cause the elongated flexible member to ride over them as the ground pin is being moved to an extended position, and interengaging shoulders between the flexible member and the housing for retaining the ground pin in an extended position after the flexible member rides over the cam structure, the flexible member being deflectable by depressing on the button so that the flexible member can be disengaged from the shoulder on the housing and the ground pin can be moved to a retracted position by pushing on the button. A support structure for a printed circuit within the housing of an electrical device including support members within the housing for firmly mounting the printed circuit, an elongated lead between the printed circuit and the movable ground pin described above, and a protective cover separating the elongated lead from sharp points on the printed circuit so that the elongated lead will not be abraded during its movement back and forth with the ground pin.
In an electrical device having a housing and prong means for insertion into an electrical socket, a retractable ground pin construction comprising an elongated ground pin having an inner end and having an outer end for movement between retracted and extended positions relative to said housing, means on said housing for rectilinearly guiding said ground pin for movement between said extended and extracted positions relative to said housing, an elongated member in said housing, first and second ends on said elongated member, means securing said first end of said elongated member to said inner end of said ground pin, interengaging means for interfitting with and selectively positively locking said elongated member to said housing to fixedly lock said ground pin in said extended position, and manually actuatable means secured to said elongated member and extending through said housing to the outside thereof for effecting movement of said elongated member and said ground pin secured thereto in a rectilinear direction to said extended position wherein said interengaging means fixedly lock said ground pin in said extended position and for moving said interengaging means out of said interfitting locking engagement with said housing and effecting movement of said elongated member and said ground pin connected thereto to said retracted position.
In an electrical device having a housing and prong means for insertion into an electrical socket, a retractable ground pin construction comprising an elongated ground pin having an inner end and having an outer end for movement between retracted and extended positions relative to said housing, means on said housing for rectilinearly guiding said ground pin for movement between said extended and retracted positions relative to said housing, an elongated member in said housing, first and second ends on said elongated member, means securing said first end of said elongated member to said inner end of said ground pin, interengaging means for selectively connecting said elongated member to said housing to fixedly secure said ground pin in said extended position, and manually actuatable means secured to said elongated member and extending through said housing to the outside thereof for effecting movement of said elongated member and said ground pin secured thereto in a rectilinear direction to said extended position wherein said interengaging means fixedly secure said ground pin in said extended position and for disengaging said interengaging means to effect movement of said elongated member and said ground pin connected thereto to said retracted position, said interengaging means comprising shoulder means on said housing and abutment means on said elongated member.
An electrical device with a retractable ground pin comprising a housing divided longitudinally into first and second housing portions having first and second walls, respectively, support means in said housing for supporting a printed circuit board thereon in spaced relationship to said first wall, prong means mounted on said housing, lead means connecting said circuit board to said prong means, a ground pin having an inner end and having an outer end for movement between retracted and extended positions relative to said housing, means in said second housing portion for rectilinearly guiding said ground pin for movement between extended and retracted positions relative to said housing, an elongated member in said second housing portion, first and second ends on said elongated member, means securing said first end of said elongated member to said inner end of said ground pin, interengaging means for selectively connecting said elongated member to said second wall to fixedly secure said ground pin in said extended position, and manually actuatable means secured to said elongated member and extending through said second wall to the outside thereof for effecting movement of said elongated member and said ground pin secured thereto in a rectilinear direction to said extended position wherein said interengaging means fixedly secure said ground pin in said extended position and for disengaging said interengaging means to effect movement of said elongated member and said ground pin connected thereto to said retracted position.
An electrical device comprising a housing having first and second spaced walls, a printed circuit board, means mounting said printed circuit board in said housing relative to said first side to define a space therebetween, prong means mounted on said housing and extending outwardly therefrom for insertion into an electrical outlet, means electrically coupling said prong means to said circuit board, a ground pin, means mounting said ground pin in said space for movement between an extended position for insertion into said electrical outlet with said prong means and a retracted position wherein it is not inserted into said electrical outlet with said prong means, an elongated lead having end portions and a central portion, said end portions of said elongated lead being attached to said circuit board and said ground pin and said central portion lying in said space, said elongated lead being of a sufficient length so as to maintain said coupling relationship between said circuit board and said ground pin in both said retracted and extended positions of said ground pin, and shield means located between said circuit board and said elongated lead means to shield said central portion of said elongated lead means from engaging said printed circuit board.
Dependencies are inferred from the claim text.