US528952A

US528952A - Keyhole-guard

Info

Publication number: US528952A
Authority: US
Publication date: 1894-11-13
Anticipated expiration: 1911-11-13

Description

(N0 Mode1.)

'M. A. LINDER.

KEYHOLB GUARD. No. 528,952.

Patentd Nov. 13, 1894.

UNITED STATES AT-ENT ()FFICE.

MONS A. LINDER, or PULLMAN, ILLINOIS.

KEYHOLE-G UARD.

SPECIFICATION forming part of Letters Patent No. 528,952, dated November 13, 1894.

Application filed February 21,1894. $erial No. 501,029- (No model.)

To all whom it may concern:

' Be it known that I, MONS A. LINDER, a citizen of the United States, residing at Pullman, in the county of Cook and State of Illinois, have invented a new and useful Keyhole-Guard, of which the following is a specification.

The invention relates to improvements in keyhole guards.

The object of the present invention is to improve the construction of keyhole guards, and to provide a simple and efliective device capable of preventing a key from being turned from the exterior of a door, and also preventing the same from being forced out of the lock, whereby the latter is prevented from being picked or unlocked from the outside by a tool.

The invention consists in the construction and novel combination and arrangement of parts hereinafter fully described, illustrated in the accompanying drawings and pointed out in the claims hereto appended.

In the drawings--Figure 1 is a perspective viewof a keyhole guard constructed in accordance with this invention, and shown in engagement with a key. Fig. 2 is a similar view, thekeybeing removed. Fig. 3 is a longitudinal sectional view.

Like numerals of reference indicate like parts in all the figures of the drawings.

1 designates a keyhole guard consisting of a locking plate provided with an opening 2 conforming to the configuration of a keyhole 3. The locking plate or guard 1 is slidingly mounted longitudinally of the keyhole 3, and it is provided at its top with a narrow extension or slot 4 for engaging and readily holding the shank of a key 5. When the plate is drawn downward, as illustrated in 'Fig. 1 of the accompanying drawings, the narrow extension or slot 4 is brought into engagement with the key. The extension or slot 4 is arranged at a slight angle to the keyhole, whereby when it engages the key the latter will be slightly turned to prevent it from being forced outward by the insertion of a tool from the exterior of a door. The slot or extension 4 of the opening 2 also prevents the key from turning and the door from being unlocked from the exterior while gripping the exposed end of the key with a tool.

The keyhole guard or plate has its lower end 6 curved outward slightly to enable it to be readily grasped by the end. It may be of any desirable configuration to conform to the character of a door and lock with which it is to be used, and it may be slidingly mounted on a lock, or a lock plate, or an escutcheon plate, when a mortise lock is employed. In the drawings a plate or escutcheon 7 has portions struck up to form tongues 8, which are arranged at the sides ,of the keeper or guard and project over the top of the same.

By locating the slot 4 at an angle to the keyhole and causing the key to be slightly turned, the lug of the key will be carried away from the keyhole, and the strain, incident to any attempt to force the key out of the lock, will be borne by the lug of the key and the lock itself, and will not be communicated to the sliding plate, therebyenabling the tongues to be employed to form ways.

The locking plate is provided at opposite sides with lugs 9, located between the pairs of tongues and adapted to limit the sliding movement of the locking plate. It will be seen that the keyhole-guard is simple and comparatively inexpensive in construction; that it is positive and reliable in its operation, and may be readily applied to the ordinary construction of door or look.

Changes in the form, proportion and the minor details of construction may be resorted to without departing from the spirit or sacrificing any of the advantages of this invention.

Having described my invention, what I claim is In a key hole guard, the combination with an escntcheon plate having a key hole and provided at opposite sides of the same with projecting tongues 8, arranged in pairs and forming a longitudinal way, and a sliding locking plate having its edges engaged by said tongues, and provided with projecting lugs located between the pairs of tongues and limiting the sliding movement of the locking plate, said locking plate being provided with my own I have hereto afiixed my signature in a key hole and having at the top thereof an the presence of two witnesses. inclined 0r angularly disposed slot, arranged to engage the shank of a key and adapted to MONS UNDER 5 hold the lug thereof away from the key hole, Witnesses:

substantially as described. SWAN TORNQUIST,

In testimony that I claim the foregoing as J. O. MINTIRO.