Patents by Inventor Tom M. Lawrence

Tom M. Lawrence has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4116514
    Abstract: A security hinge is disclosed which includes a pair of leaves, having respectively, at least a pair of spaced end knuckles and at least one immediate knuckle disposed therebetween. Each knuckle includes a central axial bore, the bores being aligned co-axially. A pair of pins are provided, each pin having a head portion disposed in an end knuckle bore for rotation in unison therewith and a body portion thereof disposed within an intermediate knuckle bore to maintain the leaves in assembly and permit relative rotation therebetween the pin and intermediate knuckle. Stop means, are provided interiorly of the bores, against which the heads of the respective pins abut, thus preventing the pins from being driven completely through the end knuckle bores in the axially inward direction. Since the pins are recessed within the bores, and one prevents the other from being forced out of the bores in the axially outward direction, unauthorized disassembly of the hinge is precluded.
    Type: Grant
    Filed: July 22, 1977
    Date of Patent: September 26, 1978
    Assignee: Lawrence Brothers, Inc.
    Inventor: Tom M. Lawrence