US3295344A

US3295344A - Bit key lock guard

Info

Publication number: US3295344A
Authority: US
Inventors: Leon W Hankins
Original assignee: Individual
Current assignee: Individual
Priority date: 1964-12-08
Filing date: 1964-12-08
Publication date: 1967-01-03
Anticipated expiration: 1984-01-03

Description

Jan. 3, 1967 w. HANKINS BIT KEY LOCK GUARD Filed Dec. 8, 1964 INVENTOR. Zia/M %//%/w///VJ United States Patent 3,295,344 BIT KEY LOCK GUARD Leon W. Hankins, R0. Box 224, 2646 W. Walnut St, Springfield, Mo. 65301 Filed Dec. 8, 15 64, Ser. No. 416,766 3 Claims. (Cl. 7tl-43) This invention relates to a guard for bit key operated mortise or rim lock.

Heretofore, devices intended to prevent locks of the kind indicated from being operated and opened from the out sides of doors and the like, have only partially achieved their purposes since these devices failed to preclude operation of their bolts, by various means, such as the insertion and manipulation of implements through their keyholes, and/or the application of vibration or other shocks to the lock mechanisms.

The primary object of the present invention is the provision of a reliable, efiicient, easily applied guard, which is adapted to be secured to a bit key and installed through a lock keyhole, from the inner side of the lock, in such a way that the bit of the key is securely held in contact with the lock bolt and positively precludes opening operation of the bolt by any means applied from the outer side of the lock.

Another object of the invention is the provision of a guard of the character indicated above, which is of simple and uncomplex construction, so that it is adapted to be made and sold as an inexpensive and positive means of rendering ordinary locks, of the indicated types, burglarproof, and as means for preventing keys from being jarred loose from the locks, in open positions of the related doors, or the like.

In the drawings:

FIGURE 1 is a fragmentary edge elevation of a door equipped with a mortise type, bit key operated lock, equipped with a guard of the present invention;

FIGURE 2 is an inside elevation of FIGURE 1;

FIGURE 3 is a vertical section taken on the line 3.3 of FIGURE 1, showing the guard retaining the keyoperated bolt of the lock in extended or locking position;

FIGURE 4 is a fragmentary perspective view, showing the guard in process of installation relative to the lock and its key;

FIGURES 5 and 6 are perspective views of a left-hand guard, respectively.

Referring in detail to the drawings, D generally designates a door having a free edge It), in which is flush mortised a conventional bit key operated lock 12. Rotary handles 14 and 16 extend from the out side and the inner side, respectively, of the door D, and are operatively secured on related ends of a polygonal shaft 13, which operates a spring latch bolt 20.

The lock 12 comprises a vertically elongated case 22, containing, within its upper part, the spring latch bolt 20, which extends through an opening 24, provided in the lock face 26.

Working through an opening 28, in the lock face 26, at a point spaced below the spring bolt 20, is a locking bolt 36 which is formed, in its lower edge, adjacent to its inner end, with a generally V-shaped notch 32, having outer and inner cam edges 34 and 36, respectively. Aligned keyholes 38 are provided in the side walls 40 of the lock case 22, beneath the locking bolt 30, in the region of the notch 32. A conventional bit key 42 comprises a round shaft 44, having a stop collar 46, adjacent its free end, and a lateral radial flat bit 48 located be tween the stop collar and the free end of the shaft, and an eye 49 on its outer end.

The bit 48 is adapted to be passed through a related keyhole 38, into the locking bolt notch 32, for extending and retracting the locking bolt 30. With reference ice to FIGURE 3, the key 42, after insertion in the lock, is adapted to be rotated, in a clockwise direction, so as to cause the bit 48 to bear against the inner cam edge 36, of the notch 32, for retracting the bolt 30; and to be rotated, in the opposite direction, for operatively engaging the outer cam edge 34, for extending the bolt 30, to the position shown. Positive retention of the locking bolt 30, in the extended locking position is obtained by a guard 50 of the present invention.

The guard 50 for use where the lock is at the left-hand edge of a door, as shown in FIGURE 5, comprises a longitudinally elongated fiat head 52, formed with two or more longitudinally spaced threaded holes 54, adapted to receive the shank 56 of a wing-screw 58, having a relatively large diameter head 60. A longitudinally elongated, relatively narrow, substantially fiat guard arm 62 extends from the inner end of the flat head 52. The arm 62 is substantially narrower than the head 52 and is offset to and is flush with one side edge 64 thereof.

As shown in FIGURES l, 2 and 4, the side edge 64 of the guard head 52 is, in the installed position of the guard, the depressed edge of the head 52, the arm 62 is twisted out of the plane of the head 60, into a substantially perpendicular plane, disposed at an acute angle to the plane of the head. As shown in FIGURE 3, the arm 62 has upwardly converging opposed sides 66 and 68, respectively, and has a slightly rounded lower edge 70, and a fiat upper edge 72. While the cross section of the arm 62, as shown in FIGURE 3, is less than the width of the slot 74 of the keyhole 38, in which the outer end portion of the arm 62 is located, in the installed position of the guard, the arm 62 must be wide enough to preclude substantial turning of the arm in the keyhole.

The guard 50 is installed by turning the key 42 in the lock so as to extend the bolt 36 to its locking position, as shown in FIGURE 3. The guard arm 62 is then inserted in the slot '74 of the keyhole 38, beneath the key, as far as the arm 62 will go. The eye 49 of the key 42 then overlies the guard head 52. Then, if necessary, the guard 50 is somewhat drawn out, until the key eye 49 registers with one of the threaded holes 54 in the guard head 52. The shank 56 of the wing-screw 58 is then engaged in this hole 54 and the wing-screw tightened to secure the key to the guard 50.

It will be understood that the downward angulation of the guard head 52, relative to the guard arm 62, and relative to the keyhole slot 74, corresponds to the upward angulation of the key bit 48, in its locking bolt retaining position, and that the substantially rotationless engagement of the guard arm 62, in the keyhole 38, precludes rotation of the key 42, relative to the lock, and thereby prevents rotation of the key bit 48, out of the locking bolt retaining position shown in FIGURE 3.

The guard Stl serves also to prevent the key 42 from being jarred out of the lock '12, when the door D is opened or closed, and slammed.

A .guard 50a, shown in FIGURE 6, is for use where the lock is on the right-hand edge of the door. The guard Sila is the same in construction as the left-hand guard, shown in FIGURE 5, except that the angulation of its head 52a, relative to its arm 62a, is the reverse of the head 52 of the guard 50, and extends from the opposite side of its arm 62a.

What is claimed is:

I. In combination, a lock case containing an extensible and retractable locking bolt, said locking bolt being formed with a notch having outer and inner cam edges, the case being formed with a keyhole located in the region of said notch, a key having a shaft formed with an eye on its outer end and with a lateral bit at its inner end, the key being engaged through the keyhole with its bit positioned in said notch, the key being adapted to be rotated in opposite directions for operatively engaging the bit with the cam edges for extending and retracting the locking bolt, and a guard fixed to the key, said guard having an arm engaged non-rotatably through the keyhole, said keyhole has a vertical slot through which the guard arm is non-rotatably engaged, said guard comprising a relatively wide flat head on the outer end of said arm, said head being angled relative to the guard arm, the bit of the key being in upwardly and outwardly angled position relative to the keyhole slot in engagement with the outer cam edge of the bolt notch in the extended position of the bolt and the guard head being in an inwardly and downwardly angled position relative to the keyhole slot, the bit and the eye of the key being located in the same plane, the head of the guard and the key eye being angled out of the, horizontal, a side of the head being engaged with a side of the key eye, and means fixing the key eye to one side of the guard head.

2. In combination, a lock case containing an extensible and retractable locking bolt, said locking bolt being formed with a notch having outer and inner cam edges, the case being formed with a keyhole located in the region of said notch, a key having a shaft formed with an eye on its outer end and with a lateral bit at its inner end, the key being engaged through the keyhole with its bit positioned in said notch, the key being adapted to be rotated in opposite directions for operatively engaging the bit with the cam edges for extending and retracting the locking bolt, and a guard fixed to the key, said guard having an arm engaged non-rotatably through the keyhole, said keyhole has a vertical slot through which the guard arm is non-rotatably engaged, said guard comprising a relatively wide flat head on the outer end of said arm, said head being angled relative to the guard arm, the bit of the key being in upwardly and outwardly angled position relative to the keyhole slot in engagement with the outer cam edge of the bolt notch in the extended position of the bolt and the guard head being in an inwardly and downwardly angled position relative to the keyhole slot, the bit and the eye of the key being located in the same plane, the head of the guard and the key eye being angled out of the horizontal, a side of the head being engaged with a side of the key eye, and means fixing the key eye to one side of the guard head, the guard arm being substantially narrower than the guard head and offset to one side edge of the guard head.

3. In combination, a lock case containing an extensible and retractable locking bolt, said locking bolt being formed with a notch having outer and inner cam edges, the case being formed with a keyhole located in the region of said notch, a key having a shaft formed with an eye on its outer end and with a lateral bit at its inner end, the key being engaged through the keyhole with its bit positioned in said notch, the key being adapted to be rotated in opposite directions for operatively engaging the bit with the cam edges for extending and retracting the locking bolt, and a guard fixed to the key, said guard having an arm engaged non-rotatably through the keyhole, said keyhole has a vertical slot through which the guard arm is non-rotatably engaged, said guard comprising a relatively wide fiat head on the outer end of said arm, said head being angled relative to the guard arm, the bit of the key being in upwardly and outwardly angled position relative to the keyhole slot in engagement with the outer cam edge of the bolt notch in the extended position of the bolt and the guard head being in an inwardly and downwardly angled position relative to the keyhole slot, the bit and the eye of the key being located in the same plane, the head of the guard and the key eye being angled out of the horizontal, a side of the head being engaged with a side of the key eye, and means fixing the key eye to one side of the guard head, said means comprising longitudinally spaced threaded holes in the guard head adapted to be registered with the opening of the key eye, and a clamping bolt having a shank threaded into a registered hole and an enlarged diameter head bearing upon the key eye.

References Cited by the Examiner UNITED STATES PATENTS 30,368 10/1860 Wheeler 70-430 567,344 9/1896 Hollingsworth et al. 70-430 1,109,787 9/1914 Robinson 70-430 1,235,098 7/1917 Berggren 70-430 1,307,496 6/1919 Holcomb 70-429 2,429,913 10/1947 Bald 70-430 EDWARD C. ALLEN, Primary Examiner.

P. TEITELBAUM, Assistant Examiner.

Claims

1. IN COMBINATION, A LOCK CASE CONTAINING AN EXTENSIBLE AND RETRACTABLE LOCKING BOLT, SAID LOCKING BOLT BEING FORMED WITH A NOTCH HAVING OUTER AND INNER CAM EDGES, THE CASE BEING FORMED WITH A KEYHOLE LOCATED IN THE REGION OF SAID NOTCH, A KEY HAVING A SHAFT FORMED WITH AN EYE ON ITS OUTER END AND WITH A LATERAL BIT AT ITS INNER END, THE KEY BEING ENGAGED THROUGH THE KEYHOLE WITH ITS BIT POSITIONED IN SAID NOTCH, THE KEY BEING ADAPTED TO BE ROTATED IN OPPOSITE DIRECTIONS FOR OPERATIVELY ENGAGING THE BIT WITH THE CAM EDGES FOR EXTENDING AND RETRACTING THE LOCKING BOLT, AND A GUARD FIXED TO THE KEY, SAID GUARD HAVING AN ARM ENGAGED NON-ROTATABLY THROUGH THE KEYHOLE, SAID KEYHOLE HAS A VERTICAL SLOT THROUGH WHICH THE GUARD ARM IS NON-ROTATABLY ENGAGED, SAID GUARD COMPRISING A RELATIVELY WIDE FLAT HEAD ON THE OUTER END OF SAID ARM, SAID HEAD BEING ANGLED RELATIVE TO THE GUARD ARM, THE BIT OF THE KEY BEING IN UPWARDLY AND OUTWARDLY ANGLED POSITION RELATIVE TO THE KEYHOLE SLOT IN ENGAGEMENT WITH THE OUTER CAM EDGE OF THE BOLT NOTCH IN THE EXTENDED POSITION OF THE BOLT AND THE GUARD HEAD BEING IN AN INWARDLY AND DOWNWARDLY ANGLED POSITION RELATIVE TO THE KEYHOLE SLOT, THE BIT AND THE EYE OF THE KEY BEING LOCATED IN THE SAME PLANE, THE HEAD OF THE GUARD AND THE KEY EYE BEING ANGLED OUT OF THE HORIZONTAL, A SIDE OF THE HEAD BEING ENGAGED WITH A SIDE OF THE KEY EYE, AND MEANS FIXING THE KEY EYE TO ONE SIDE OF THE GUARD HEAD.