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Publication numberUS3343387 A
Publication typeGrant
Publication dateSep 26, 1967
Filing dateApr 16, 1965
Priority dateApr 16, 1965
Publication numberUS 3343387 A, US 3343387A, US-A-3343387, US3343387 A, US3343387A
InventorsBlake Cochran Aldrich
Original AssigneeJoe Paoli
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Door knob shield and lock
US 3343387 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

Se t. 26, 1967 A. B. COCHRAN DOOR KNOB SHIELD AND'LOCK Filed April 1s, 1965,

,r/ a- I.

irral /i) United States Patent 3,343,387 DOOR KNOB SHIELD AND LOCK Aldrich Blake Cochran,.San Francisco, Calif., assignor to Joe Paoli, San Francisco, Calif. Filed Apr. 16, 1965, Ser. No. 448,744 4 Claims. (Cl. 70 424 ABSTRACT OF THE DISCLOSURE This invention relates to a shield for door knob locks, and particularly to a device arranged to be padlocked onto a knob lock to prevent operation of the knob lock without first unlocking the shield.

Summary of the invention In terms of broad inclusion, this invention comprises a collar arranged to detachably engage the stem portion of a door knob lock and provide it with a shroud arranged to cover the keyhole of the knob lock. The collar is provided with means engageable by an ordinary padlock for locking the collar and shroud onto the knob.

It is among the objects of this invention to provide a shield which may be locked onto a door knob having locking mechanism of conventional form to prevent operation of the knob look by key in its normal manner.

It is also an object of the invention to provide an auxiliary locking mechanism which may be detachably applied to the locking knob of a room, such as a hotel or motel room, by an occupant temporarily leaving the room to prevent intrusion or unauthorized entry by persons possessing a key by which the knob lock might otherwise be operated during the occupants absence.

A further object of the invention is to provide a knob lock shield which may be manufactured economically, which may be easily carried and applied to any knob lock by transient guests of hotels and motels, and which will accommodate an ordinary padlock as an auxiliary locking means.

These and other objects, some of which with the foregoing will be more fully explained in the following specification, are accomplished by means of the device shown in the accompanying drawings forming a part of this specification. The invention of course, is not limited to the illustrative embodiments shown in the drawings as the invention may be otherwise embodied within the scope of the appended claims.

Brief description of the drawings of a preferred form of the Description of the preferred embodiments In terms of greater detail the door knob shield and lock of my invention comprises a collar, designated in general by the numeral 11, formed of a central section 12 and end sections 13 and 14 hinged to the ends of the section 12 by hinges 15. The free ends of the sections 13 and 14 are shaped to form lugs 16 arranged to be moved into proximate parallel relation when the collar embraces the stem portion 17 of a knob lock 18. Openings 19 in the lugs 16 match when the lugs are moved to locking position, and are arranged to receive the loop 20 of a padlock 21 of conventional structure.

A shroud 22 is attached to the collar 11, preferably as an integral extension formed upon an edge of the central collar section 12. The shroud 22 is shaped to nest over the knob and cover the keyhole 23 of lock mechanism 24 axially disposed within the knob 18 and stem 17. Preferably the shroud 22 encircles the upper portion of the knob 18, and is provided with an extension 26 shaped to extend downwardly and under the lower portion of the knob.

The device is applied to a knob by spreading the end sections 13 and 14 enough to pass over the sides of the stem 17. At the same time, the shroud is cupped over the knob. The sections 13 and 14 are then moved to position the lugs 16 in proximate parallel relation, and the loop 20 of padlock 21 is inserted through the matching openings 19 for locking the collar onto the stem.

If desired, the lower end of the shroud extension 26 may be extended and shaped to form a locking lug 27 having an opening 28 matching with the openings 19, the loop of the padlock being inserted through the matching openings for locking the shroud to the collar lugs, as shown in FIG. 5 of the drawings.

The collar and shroud may be made of any suitable material and in varying designs to fit various types and sizes of knob locks. Preferably the device is made of metal of a thickness sufiicient to resist normal forces which might be applied to displace the device from the knob. At the same time the device should be sufficiently light and compact to be conveniently carried in the luggage of a traveler, so as to be available for use on the knobs of hotel or motel doors.

I claim:

1. A shield for door knobs having key actuated lock mechanism extending axially therethrough with a key hole in the outer end of the knob comprising a collar formed as a center section of substantially semi-circular shape arranged to seat upon a stem portion of a knob between the knob and a door, and a pair of end sections of substantially quadrant shape pivotally hinged to the ends of the center section and arranged to substantially encircle said stern a shroud attached to the center section of the collar and shaped to extend over the keyhole when the collar embraces the stem; and means upon opposing end sections of the collar arranged to be engaged by separate locking means operable to lock the collar and shield onto the knob.

2. A shield for a door knob as defined by claim 1 wherein said end sections of the collar are provided with lugs movable into proximate position and having matching openings adapted to be engaged by a padlock for locking the shield into the knob.

3. A shield for a door knob as defined by claim 1 wherein said end sections of the collar are provided with lug portions movable into substantially parallel relation and the shroud being provided with a lug arranged to be moved into matching relationship with the lug portions of the collar; said lug and lug portions having openings formed therein and arranged to be alined for engagement by a padlock for locking'the shield onto the knob.

4. A shield for a door knob as defined by claim 1 wherein the outer ends of said end sections are shaped to form lugs m-oveable into proximate parallel relationship and having openings registering to receive a padlock by Which the collar may be locked in embracing engagement with the stem, the shroud being attached to the center section and being provided with an extension moveable 3 4 to a locking position between the lugs and having an open- 1,829,444 10/ 1931 Goebel et a1. 74-416 ing arranged to register with the openings of said lugs. 3,167,945 2/ 1965 Goodman 70428 3,245,240 4/1966 De Forrest 70-209 References Cited FOREIGN PATENTS UNITED STATES PATENTS 1,329,913 2/1920 McGuire 70-209 X ,4 9, 2 12/1 22 ohns n 7 4 BOBBY Y, Primary Examiner.

928,141 5/1947 France.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1329913 *Jun 7, 1919Feb 3, 1920Mcguire PatrickSteering-wheel lock for automobiles
US1439552 *Aug 19, 1921Dec 19, 1922Glen E JohnsonSafety appliance for door locks
US1829444 *Mar 12, 1930Oct 27, 1931Mosler Safe CoDial cover
US3167945 *Jul 3, 1963Feb 2, 1965Goodman FrankKeyhole obstructing locking devices
US3245240 *May 8, 1964Apr 12, 1966James And William De ForrestKnob protector
FR928141A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3457745 *Oct 5, 1967Jul 29, 1969Charles H BarberDoorknob keyhole guard
US3479850 *Jun 10, 1968Nov 25, 1969Frye Jud KMaster key attachment
US4285221 *Jun 18, 1979Aug 25, 1981Atchisson Maxwell GRetrofit doorknob lock apparatus
US4561273 *May 21, 1984Dec 31, 1985Robinson Forrest JDoorknob security apparatus
US5551242 *Mar 14, 1984Sep 3, 1996Halliburton CompanyFlameless nitrogen skid unit
US20150176308 *Dec 19, 2014Jun 25, 2015Joseph TalpePushbutton combination lock
U.S. Classification70/424
International ClassificationE05B13/00
Cooperative ClassificationE05B13/001
European ClassificationE05B13/00B