Patent Application
20110198866
The present invention relates to reciprocating bolt-type fasteners for securing doors, gates, windows and the like in a closed position, and more specifically to such fasteners which are lockable in position to prevent unwanted access from the side of the enclosure where the bolt fastener is located.
Bolt lock fasteners are well known in the art, exemplified by U.S. Pat. No. 48,555 to Hart, disclosing a plate forming a barrel through which a bolt reciprocates, and a corresponding strike receiving a free end of the bolt in the extended or locked position. The barrel is typically mounted to the moving door or window, and the strike is fixed to the surrounding jamb or frame. Both the plate and the strike have peripheral flanges used to secure the plate to the door or jamb, respectively. Also, the barrel includes transverse, usually vertical, slots for accommodating the bolt handle in either designated extended (locked) or retracted (released) positions. A main drawback of this type of lock is that when used in applications where the bolt is outside the enclosure being protected, such as a shed or cabinet, the locking effect can be readily neutralized by removing the exposed fasteners on the barrel flange. Another disadvantage of this arrangement is the inability to accommodate a padlock for restricting access to the enclosure being locked.
Some of the drawbacks of the traditional bolt design of Hart are addressed in U.S. Pat. No. 1,368,711 to Foley, disclosing a sliding bolt and strike where the fasteners securing the barrel are hidden behind the reciprocating bolt. The bolt is provided with apertures for accommodating a padlock. However, by modifying the barrel to provide access to the padlock apertures, the holding straps of the barrel are inherently weak and prone to bending or breakage by a pry bar for removing the bolt to gain access to the enclosure. Also, the bolt is constructed of shaped sheet material, which is inherently weaker than a solid rod-style bolt, as disclosed in Hart.
Thus, there is a need for providing an improved security bolt that addresses the drawbacks identified above, while being capable of competitively manufactured to conventional designs.
The above-identified need is met by the present security bolt, which provides a unitary case or barrel with hidden flanges located behind the bolt, and secured by fasteners which are hidden from view by an exterior cover of the case and the rod-like bolt. The case is configured for substantially enclosing the bolt in both the locked and unlocked positions. Apertures are provided in the case and matching strike for accommodating a padlock in either a locked or unlocked, storage position. Also, unitary support tabs are provided to both the case and the strike for fastening the components to the edge of the door or jamb. In addition, adjacent edges of the case and strike forming the enclosure are configured in an intermeshing relationship, with opposing intermeshed tabs each secured in place by fasteners for a more secure arrangement.
More specifically, a security bolt is provided, including a unitary case having a front surface, a rear surface and being formed to define a substantially enclosed, elongate passageway. A strike has a front surface, a rear surface and is formed to define a strike passageway being alignable with the elongate passageway. An elongate bolt is reciprocally engaged in the elongate passageway between a retracted position and an extended position in which a free end of the bolt is received in the strike passageway. At least one of the case and the strike is configured so that opposed edges engage each other at the rear surface along a line obscured by the respective front surface.
In another embodiment, a security bolt includes a unitary case having a front surface, a rear surface and being formed to define a substantially enclosed, elongate passageway. A strike has a front surface, a rear surface and is formed to define a strike passageway being alignable with the elongate passageway. An elongate bolt is reciprocally engaged in the elongate passageway between a retracted position and an extended position in which a free end of the bolt is received in the strike passageway. Both the case and the strike are configured so that opposed edges engage each other at the rear surface along a line obscured by the respective front surface. The rear surfaces are provided with interengaging tabs forming a notched, intermeshing relationship along the opposed edges of the formed case.
In still another embodiment, a security bolt includes a unitary case having a front surface, a rear surface and being formed to define a substantially enclosed, elongate passageway. A strike has a front surface, a rear surface and is formed to define a strike passageway being alignable with the elongate passageway. An elongate bolt is reciprocally engaged in the elongate passageway between a retracted position and an extended position in which a free end of the bolt is received in the strike passageway. Both the case and the strike are configured so that opposed edges engage each other at the rear surface along a line obscured by the respective front surface. The front surface of the case is broken only by a pair of padlock apertures, and a pair of connected, transverse bolt slots, the front surface of the strike is broken only by a pair of storage padlock apertures.
Referring to
The case 12 is unitary, in that it is formed from a single piece of sheet material, preferably sturdy sheet metal or steel which may be hardened as desired. Upon being formed as desired the case 12 includes a front surface 24 and an opposite rear surface 26, the case forming a substantially enclosed, elongate passageway 28 configured for accommodating a linearly reciprocating bolt 30.
Referring now to
The bolt 30 reciprocates in the enclosed passageway 28 between a retracted position in which the door 16 may be opened, and an extended position (
Referring now to
It will be seen that the rear surfaces 26, 36 are each provided with at least one and preferably a plurality of fastener apertures 56. Further, it is contemplated that the edges 48, 50 and 52, 54 form a plurality of interengaging tabs 58 forming a notched, intermeshing relationship such that the line formed by the interengaging edges is not straight, but forms a block, zigzag shape. This arrangement is believed to increase the integrity of the case 12 and the 14 once they are mounted in place. Further, in the preferred embodiment, each tab 58 is provided with one of the fastener apertures 56. The apertures 56 are located in a staggered orientation. However, the arrangement and number of fastener apertures 56 may vary to suit the application.
Referring now to
Referring now to
It will also be seen that the strike 14 has an end 78 open to receive the free bolt end 40, the end 78 being opposite the end 76, which is provided with a stop or blocking formation 80 (
To control the movement of the bolt 30 between the extended and retracted positions, the case 12 is provided on the front surface 24 with a pair of transversely projecting bolt slots 82 configured for receiving the bolt handle 46 in a selected one of the retracted and extended positions. Also, as is known in the art, the slots 82 are connected by an axially oriented slot 84, the combination forming a general “H”-shape when viewed from above or from the front. It will be seen that the front surface 24 of the case 12 is broken only by the padlock aperture set 66 which includes a pair of apertures, and the connected transverse bolt slots 82. Similarly, the front surface 34 of the strike 14 is broken only by the storage padlock aperture set 72, also including a pair of apertures.
Referring now to
Thus, it will be seen that the present security bolt 10 addresses and overcomes the above-identified drawbacks of the prior art. The case 12 substantially hides the bolt 30, and has several features which make the bolt 10 more secure than conventional locks, especially when the bolt is located on the exterior of the enclosure being protected. These features include the hidden fastener apertures 56, the obscured and non-linear edges 48, 50, 52, 54 and the jam tabs 60, 62.
While a particular embodiment of the present security bolt has been shown and described, it will be appreciated by those skilled in the art that changes and modifications may be made thereto without departing from the invention in its broader aspects and as set forth in the following claims.
