Patent ID: 7930913

Claim:
A ring-type meter lock comprising a ring, first and second ends on said ring, a lock housing on said first end of said ring, a slot in said lock housing, a bore in said lock housing extending from a bore entrance to said slot, a latch unit in said lock housing bore, said latch unit including a cam unit having a cam unit bore that carries a lock pin having a first end and a second end, said first end of said lock pin being situated within said lock housing bore entrance such that only a first end face of said lock pin is accessible via said lock housing bore entrance, said second end of said lock pin being enterable into and withdrawable from said slot via said lock housing bore, a tongue on said second end of said ring enterable into said slot, an opening in said tongue arranged to receive said second end of said lock pin when said tongue is at a predetermined position in said slot, thereby latching said tongue, a key-receiving configuration on said first end face of said lock pin for receiving a security key that rotates said lock pin, said cam unit further including at least one cam surface on which said lock pin is rotatably supported, said cam unit and said at least one cam surface being fixedly positioned in said lock housing, said lock pin being resiliently biased by a biasing element of said latch unit for movement within said cam unit bore from an unlatching position wherein said second end of said lock pin is not received in said opening of said tongue and wherein said lock pin engages a first part of said at least one cam surface in a first rotational orientation toward a latching position wherein said second end of said lock pin is received in said opening of said tongue and wherein said lock pin engages a second part of said at least one cam surface in a second rotational orientation, and said first part of said at least one cam surface having a curvilinear portion that causes said lock pin to continuously translate during movement between said latching position and said unlatching position as said lock pin is rotated.