초록 ▼

A tamper resistant fastener, which can only be rotated with a specific key, is described. The fastener includes a head for rotation about a vertical axis. The head is provided with the least two cutouts in the head of the faster spaced away from the vertical axis, the cutouts having a discontinuous

A tamper resistant fastener, which can only be rotated with a specific key, is described. The fastener includes a head for rotation about a vertical axis. The head is provided with the least two cutouts in the head of the faster spaced away from the vertical axis, the cutouts having a discontinuous sidewall. The side wall of each of the cutouts has a first generally vertical engaging surface for engagement by a mating member on a specific key for clockwise rotation of the head about the vertical axis and a second generally vertical engaging surface for engagement by the mating member on the specific key for counter clockwise rotation of the head about vertical axis. The side wall of the cutout is interrupted adjacent the second engaging surface to prevent engagement by a tool other than the specific key and thereby prevent rotation of the fastener in a counter clockwise direction by a tool other than the specific key.

대표청구항 ▼

1. A tamper resistant fastener system comprising:a head having a smooth, rounded top surface and a longitudinal axis; at least two cutouts extending into said top surface, and, a key having a head engaging portion and at least two depending mating members each having a periphery and a radius; wherei

1. A tamper resistant fastener system comprising:a head having a smooth, rounded top surface and a longitudinal axis; at least two cutouts extending into said top surface, and, a key having a head engaging portion and at least two depending mating members each having a periphery and a radius; wherein, each of said cutouts includes a sidewall parallel to said longitudinal axis and a floor normal to said longitudinal axis, said floor being bounded along a first side by said sidewall and being unbounded along a second side; and, said sidewall including a first portion extending in a generally radial direction from said axis and a second portion running in a generally circumferential direction, said second portion including a recess having a radius equal to the radius of said at least two depending members and a shape complimentary to a portion of the periphery of said at least two depending mating members.