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Publication numberUS2965741 A
Publication typeGrant
Publication dateDec 20, 1960
Filing dateJun 30, 1959
Priority dateJun 30, 1959
Publication numberUS 2965741 A, US 2965741A, US-A-2965741, US2965741 A, US2965741A
InventorsAnthony Blazina
Original AssigneeAnthony Blazina
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Lock defroster
US 2965741 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

Dec. 20, 1960 A. BLAzlNA LOCK DEFROSTER Filed June 30, 1959 FIG.|

FIG. 2

[III] United States This invention relates to a lock defroster and more particularly, to a device for treating the locks of automobiles to free the same from binding due to ice.

When locks are subjected to` high moisture and conditions of low temperature, the moisture in the lock freezes and binds the lock and prevents its operation. Additionally, when subjected to such conditions, ice may block the passage wherein the key is inserted. This problem is particularly acute of door locks in automobiles where the lock is often exposed to water and cold weather conditions. Moreover, it is difiicult to thaw such locks because they are recessed in the door of the automobile.

It is therefore amongst the primary objects of the present invention to provide a device for defrosting locks which is of simple construction, eicient in operation and may be readily carried about on the person.

It is another important object of the .present invention to provide a device of this class which may not be accidentally energized.

It is still a further object of the present invention to provide a device of this class which may readily be assembled and disassembled permitting new parts and component-s to be easily substituted for defective and worn parts without damaging the unit.

Briefly stated, the device of the present invention coinprises a casing, a thermally conductive member carried by said casing and extending outwardly thereof, an energizing circuit within said casing including a source of current, said circuit including an electrical heating element mounted in heat exchanging relationship with said member, a switch in said circuit for opening and closing the same, the heating element being energized when the circuit is closed.

A fuller understanding of the invention and the manner in which its objectives and advantages may be realized will become apparent from the following detailed description thereof taken in connection with the accompanying drawing wherein:

Fig. l is a longitudinal sectional view of a lock defroster in accordance with the present invention;

Fig. 2 is an end view, partly in section, of the device of Fig. l; and

Fig. 3 is a perspective view showing a lock defroster in accordance with the present invention in use.

Referring now to the drawing, a lock defroster in accordance with the present invention is shown packaged within casing and consists of a at, thermally conductive element of relatively narrow gauge having a blade portion 12 and a base portion 13 extending, respectively, exteriorly and interiorly of the casing; a heating coil `14 positioned in heat exchanging relationship with the base portion 13 of the thermal element; and means for energizing the heating coil, s-aid means, as is evident from the drawing, being completely contained within casing 10.

The size of blade 12 is ysuch that it may be inserted into the key passageway of a conventional automobile lock without difficulty.

arent O 2,965,741 Patented Dec. zo, 1960 ICC A protective housing or cover 18 is provided for blade 12 and is frictionally maintained in slidable engagement with the blade end of casing 10. When telescoped over casing 10, housing 18 forms a protective chamber 20 for blade 12. Housing 18 may readily be removed from the casing to expose the blade for use, as is shown in Fig. 3.

Casing 10 and housing 18 should be of plastic or other non-conductive composition. If the clearance between the casing and the housing is close so as to establish a friction fit, housing -18 will remain seated upon casing 10, as aforesaid. A longitudinal slot, not visible in the drawing, is provided at the lower end of the housing so that the housing may clear push button 22 to abut flange 23 which acts as a stop.

Wall 24 of casing 10 is pivotally -aixed to the remainder of the casing by hinges 26. Access may be had to the interior of the casing by removing housing 18 and swinging hinged wall 24 away from the body of the casing.

As may be seen, heating coil 14 is housed within a chamber 28 formed by members 30 and 32 which are hung from the casing wall on screws 34 and tightly clamped together by clamping nuts 36. Member 30 may be formed as an integral part of the casing.

Heating coil 14 is coiled about the base 13 of the thermal element and insulated therefrom by heavy duty wax paper 29. The thermal element, which presents a flat clampable surface, is firmly clamped between members 38 and 32 as is one of the arms of the Lshaped resilient conductor 38 which also presents a at clampable surface.

Conductor 38 is spaced to one side of the thermal element, as is best seen in Fig. 2, and is affixed to one end of coil 14 while at Conductor `40 is affixed to the other end thereof. Conductor 40, which extends from the terminals 41 of batteries 42, is also firmly clamped between members 30 and 32. The ends of conductors 33 and 40 are formed so that the coil may be reliably anchored thereon.

The negative terminals of batteries 42 are in contact with one end of L-shaped conductor 4-4 which is firmly mounted on the casing. The other arm of conductor 44 clamps the batteries firmly in position against the side walls of the casing. Additionally, conductor 40 assists in preventing the longitudinal shift of the batteries in the casing.

It may be seen that the lower arm of conductor 38 abuts the base of push button plunger 22. When the push button is fully depressed, it forces conductor 38 against conductor 44 to complete the circuit. When the push button is released, it is urged outwardly of the casing by conductor 38 which assumes its original position spaced from conductor y44. This is due to the resilient nature of conductor 38.

The push button plunger 22 is arranged so that if the push button is depressed with the housing 18 mounted on the casing, conductor 38 will fail to make contact with conductor 44 by a distance equal to the thickness of the housing wall. Therefore, in order to energize the device, it is necessary to remove housing 18 from casing 10. This feature prevents the unit from being accidentally energized.

When the circuit is closed as aforesaid, resistance coil 14 heats up. This heat is transferred to the base 13 of the thermal element which is maintained in heat exchanging relationship with the coil and subsequently to blade 12.

With this arrangement, I have found that blade 12 may be heated sufficiently to thaw out a frozen locking mechanism and, additionally, its key passageway.

It may be seen that by reason of the present invention,

a lock defroster has been provided which is of relatively Simple and inexpensive construction, efficient in operation and Which may readily be carried about on the person. Additionally, the ultimate defrosting element is not included in the electrical circuitry of the device. Furthermore, the heating mechanism of the present invention along with the heatable blade may readily be assembled and disassembled by reason of the construction and arrangement of parts, and new parts substituted therein for faulty or worn parts.

Although the invention has been described in detail with respect to one preferred embodiment thereof, it will be understood by those skilled in the art, after reading this specication, that various changes and modifications may be made without departing from the spirit of the invention and the scope of the appended claim.

What is claimed as new and desired to be secured by Letters Patent is:

A lock defroster comprising a casing, a thermally conductive member mounted Within said casing and extending outwardly thereof, an energizing circuit Within said casing including 'an electrical heating element mounted in heat exchanging relationship with the thermally conductive member and electrically insulated therefrom, said heatin element being coiled, within said casing, about the thermally conductive member, a resilient contact for opening and closing the circuit, a push button plunger mounted on said casing Wall, said plunger being adapted, upon the depression thereof, to urge said contact into circuit closing position to thereby energize the heating element, said plunger being urged outwardly of said casing by said resilient contact when said push button is released to break the circuit, a removable cover for said casing, said cover being frictionally maintained in slidable engagement with said casing to forrn a protective chamber for the thermally conductive member, said cover being slotted for clearance around said push button when the same is telescoped over the casing, said cover and push button being dimensioned with respect to each other so as to make unlikely the accidental energization of the device.

References Cited in the le of this patent UNITED STATES PATENTS 2,030,285 Dinyer Feb. 1l, 1936 2,371,534 McGrath Mar. 13, 1945 2,523,518 Rapaport Sept. 26, 1950 2,530,513 Drugan Nov. 21, 1950 FOREIGN PATENTS 308,037 Great Britain Mar. 2l, 1929

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2030285 *Oct 24, 1934Feb 11, 1936George DinyerCauterizing instrument
US2371534 *Oct 21, 1941Mar 13, 1945Arthur C McgrathKeylock conditioner
US2523518 *Feb 12, 1948Sep 26, 1950Rapaport MeyerPyrographic instrument
US2530513 *Apr 7, 1949Nov 21, 1950Allan J DruganApparatus for heating motor vehicle door keys
GB308037A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3022408 *Oct 25, 1960Feb 20, 1962Wagner Robert WElectrically heated key
US3379854 *Aug 25, 1967Apr 23, 1968Jovis ArthurAuto lock de-icing
US3450859 *Jan 13, 1967Jun 17, 1969Horst BruckerDevice for heating keys for defrosting frozen locks
US3973422 *Feb 11, 1975Aug 10, 1976Lawrence Peska AssociatesDefroster key case
US4123648 *Jan 7, 1977Oct 31, 1978Clark Bob JKey for defrosting locks
US4247753 *Oct 16, 1978Jan 27, 1981Niilo JaronenBattery operated electric heating device for thawing frozen locks
US5220152 *Nov 15, 1989Jun 15, 1993Doran Edward ARechargeable battery powered electrically heated lock thawing device with built-in battery charger
DE3827026A1 *Aug 5, 1988Apr 6, 1989Antonio GrippaAntifrost car key made of copper for deicing car door locks
DE3918140A1 *May 31, 1989Feb 8, 1990Antonio GrippaMethod and key for unlocking a frozen-up lock
WO1980000164A1 *Jul 6, 1979Feb 7, 1980Landsrath WalterAccessory for flat key for a lock
U.S. Classification219/200, 219/227, 70/431, 219/201
International ClassificationE05B17/00
Cooperative ClassificationE05B17/0016
European ClassificationE05B17/00D