Abstract: A wrenchable C-clamp is formed with a hexagonal portion coaxial with a clamping screw and sized to fit standard open end and box wrenches. A user can apply a wrench to the wrenchable portion to hold the C-clamp in a desired position while a clamping screw is actuated.

Abstract: A coordinated door stop and latch includes a retractable stop, a sliding bolt latch, and a mechanism between the stop and latch. The sliding bolt is used to latch the door to preclude inward movement in a normal fashion. If emergency outward operation of the door is required, retraction of the stop causes ejection of the sliding bolt from its strike opening, thereby enabling resuce door operation.

Abstract: A light duty hinge is formed by a pair of hinge leaves from which include interfitting tabs, the leaf pads and tabs being of uniform thickness. Holes provided in the tabs afford, when the tabs are interfitted, axially aligned openings for receiving the hinge pin.

Abstract: Overhead doors operating apparatus uses a single motor power unit to operate a selected one of a plurality of overhead doors through a selectively energized coupling, such as an electromagnetic clutch, or if desired, all of the doors in unison by energizing all the couplings. Thus only one motor power unit, instead of a power unit for each door, is needed to operate selectively one or more of the doors.

Abstract: Clamping apparatus includes a plurality of C-clamps formed with at least four spaced holes in their frames. Fasteners inserted through the holes secure juxtaposed C-clamps together in any one of many relationships, whereby a variety of workpieces may be held in desired positions.

Abstract: An information storage and retrieval system includes a periodical constructed to facilitate storage and retrieval of information found therein. The periodical includes a plurality of titled articles and the like and two index pages identifying the articles. One of the index pages is adapted to be removed from the periodical for separate storage and use in a suitable filing device to facilitate retrieval of information from a series of the periodicals.

Abstract: A non-handed two knuckle hinge comprises a pair of axially aligned hinge knuckles formed respectively on adjacent edges of two hinge leaves, and a pintle extending through the bore of one hinge knuckle into the bore of the second hinge knuckle. The pintle is secured in the bore of the second hinge knuckle, and the first hinge knuckle is pivotable about the pintle. The hinge includes a first vertical thrust bearing formed between the hinge knuckles for acting as a thrust bearing when the door is attached to the hinge leaf associated with the upper hinge knuckle, and a second vertical load bearing formed between the pintle head and the first hinge knuckle for acting as a thrust bearing when the door is attached instead to the hinge leaf associated with the lower hinge knuckle. Lateral bearing surfaces are provided in the first hinge knuckle for supporting the pintle at least in the vicinity of each end of the bore of the first hinge knuckle.

Abstract: A hinge, preferably a two buckle hinge, for passing electric current between a door and frame through one or more concealed, tamperproof electrical wires includes a solid hinge pin that is disposed in the bores of adjacent hinge knuckles for providing relative pivoting of the hinge leaves. In one embodiment, the hinge pin extends partially into the bore of the knuckles to define a cavity in each of the hinge knuckles. The hinge pin includes a slot to receive one or more electrical wires extending between the cavities in the respective hinge knuckles. A conduit is formed in each hinge leaf and communicates through a hole in the respective hinge knuckle to the cavity, such that the wires extend from the cavity along the conduit and out through the back of each hinge leaf.

Abstract: A two knuckle hinge has a pair of vertical bearings so that the hinge can be used interchangeably in left-handed and right-handed door installations.

Abstract: A controlled release door holder comprises a housing having a portion defining a cylinder for containment of a fluid, a piston received in the cylinder for movement axially thereof and dividing the cylinder into first and second chambers, and a linkage between the piston and the door for moving the piston in the cylinder as a function of door movement. A spring compressed between the piston and housing biases the door toward the closed position.

Abstract: An improved hinge comprising a saw-resistant security stud which functions to inhibit any movement other than the normal intended pivotal movement of the hinge.

Abstract: A switch activating hinge comprises two hinge leaves having aligned knuckles, a hinge pin fixed in a knuckle of the first leaf and extending into a knuckle of the second leaf for aligning the leaves for relative pivotal movement with respect to each other, and a switch in the knuckle of the second leaf adjacent the hinge pin. Means are provided on the hinge pin and the switch for operating the switch in response to relative pivotal movement of the hinge pin with respect to the knuckle of the second leaf.

Abstract: An improved two knuckle hinge comprises a pair of adjacent hinge leaves on which long and short axially aligned hinge knuckles are formed. The long hinge knuckle houses a bushing in its end adjacent the short hinge knuckle to act as an anti-friction bearing. A torsion spring may also be housed in the portion of the long hinge knuckle unoccupied by the bushing for urging the leaves together. A pintle, about which the long hinge knuckle pivots, is supported in the short hinge knuckle and extends into and cooperates with the torsion spring, when the torsion spring is present in the long knuckle. Also disclosed is a two knuckle hinge that simulates the appearance of a three or more knuckle hinge. This is accomplished through the use of one or more markings such as grooves in the long hinge knuckle which simulate the appearance of gaps between knuckles.

Abstract: A switch activating hinge comprises two hinge leaves having aligned knuckles, a hinge pin fixed in a knuckle of the first leaf and extending into a knuckle of the second leaf for aligning the leaves for relative pivotal movement with respect to each other, and a switch in the knuckle of the second leaf adjacent the hinge pin. Means are provided on the hinge pin and the switch for operating the switch in response to relative pivotal movement of the hinge pin with respect to the knuckle of the second leaf.