Connect public, paid and private patent data with Google Patents Public Datasets

Keylock for electrical plugs

Download PDF

Info

Publication number
US3524029A
US3524029A US3524029DA US3524029A US 3524029 A US3524029 A US 3524029A US 3524029D A US3524029D A US 3524029DA US 3524029 A US3524029 A US 3524029A
Authority
US
Grant status
Grant
Patent type
Prior art keywords
housing
plug
socket
compartment
means
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
Inventor
Robert M Laff
Original Assignee
Robert M Laff
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Grant date

Links

Images

Classifications

    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01RLINE CONNECTORS; CURRENT COLLECTORS
    • H01R13/00Details of coupling devices of the kinds covered by groups H01R12/70 or H01R24/00-H01R33/00
    • H01R13/62Means for facilitating engagement or disengagement of coupling parts or for holding them in engagement
    • H01R13/639Additional means for holding or locking coupling parts together, after engagement, e.g. separate keylock, retainer strap
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T307/00Electrical transmission or interconnection systems
    • Y10T307/74Switching systems
    • Y10T307/747Plural switches
    • Y10T307/753Lazy-man switch type

Description

R. M. LAFF KEYLOCKFOIR ELECTRICAL PLUGS Filed July 22, 1968 INVENTOR. EMWci'fQ/fi BY Baa/471.1,

United States Patent O 3,524,029 KEYLOCK FOR ELECTRICAL PLUGS Robert M. Latf, 2844 W. Gregory St., Chicago, Ill. 60625 Filed July 22, 1968, Ser. No. 746,603 Int. Cl. H01h 9/28; H01r 13/70 US. Cl. 200-44 6 Claims ABSTRACT OF THE DISCLOSURE A locking device comprising a housing having a compartment for enclosing an electrical plug, such as an appliance plug. A socket is mounted in the housing adjacent the compartment and is connected to a line cord which in turn is connected to a conventional electrical power source. The socket is adapted to receive the electrical plug. A key-actuated switch is mounted in the housing and interposed between the socket and power source for opening or closing the electrical circuit. The device is provided with means for permanently sealing the electrical plug within the housing compartment after the plug is inserted into the socket.

BACKGROUND OF THE INVENTION This invention relates generally to electrical connectors and circuit breakers with unauthorized-use preventing means. In particular, this invention pertains to a locking device for use with electrical appliance plug to prevent the unauthorized use of the appliances.

The closest prior art includes many devices for preventing the unauthorized use of appliances. These devices fall generally into two groups: 1) keylock receptacles for appliance cord plugs; and (2) plugs which contain key-operated disabling means. The devices of the first group have the disadvantage of being too cumbersome to use because whenever the appliance is to be operated, the plug must be removed from the receptacle and inserted into an electrical outlet. The second group of articles have the disadvantage of having to be substituted for the conventional plug normally found on the appliance, by either the manufacturer or the consumer of the appliance.

Therefore, an object of this invention is to provide a locking device which can be permanently connected to existing electrical plugs and which is easy to install and operate. A further object of this invention is to provide a locking device which can be economically manufactured and sold to the consuming public at a relatively low price. Additional objects of this invention will become manifest from the description, drawings, and claims.

SUMMARY OF THE INVENTION The device of this invention includes a housing containing a compartment for retaining a conventional electrical appliance plug and a socket mounted in the housing adjacent the compartment. The socket is electrically connected to a line cord which terminates in a conventional plug, and a key-actuated switch is interposed in the line between the socket and the cord. The switch is mounted in the housing with the keyhole being externally accessible. The appliance plug is inserted into the socket and is enclosed within the compartment provided for it. A cover is permanently secured to the compartment by drive screws or like means so that the appliance plug cannot be removed without destroying the locking device. When the device is connected to a nappliance, the applitime can be controlled by the key-operated switch so that the appliance can be secured against unauthorized use.

3,524,029 Patented Aug. 11, 1970 "ice BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1 of the drawings, an appliancelocking device 10 of this invention is shown. This device includes a housing 12 having a compartment 14 for holding a conventional appliance plug, such as the threepronged plug 16 shown in FIG. 3. The housing 12 is preferably constructed of plastic or other suitable non-conductive material. The plug 16 is inserted into a socket 18 which is retained by a mounting plate 20. The cord 17 of the appliance is guided about a post 19 (see FIG. 3) and through an opening 21 in the housing 12. While a three-hole grounded type socket 18 and three-prong grounded type plugs 16 and 24 are shown, a two-hole ungrounded receptacle and ungrounded two-prong plugs may be employed for use with conventional two-pronged electrical plugs. In the latter system, two wire connections would be employed so that the ground connection 28 would be eliminated.

Referring to FIG. 3, it will be seen that the socket 18 is electrically connected to a line cord 22 which terminates in a plug 24. The socket 18 is connected to the line 22 by wire 26 and wire nut 30. A ground wire 28, shown in dotted lines in FIG. 3, extends between the socket 18 and the line 22, wire 28 being connected to the line 22 by a wire nut 32, also shown in dotted lines in FIG. 3.

Interposed between the socket and the line 22 is a switch 34. The switch is electrically connected to the socket at terminal 35 by wire 36 and is connected to the line 22 at terminal 38. The line cord 22 extends from the switch 34 about a post 37, through guides 39, into the compartment 14, and out of an opening 40 in the housing 12. The switch is actuated by a removable key 42, which is movable between open and closed positions. The switch is mounted within the housing 12 and the keyhole a is externally accessible. While any suitable key-operated switch may be employed in this invention, I have found that a 15 amp., to 277 volt A.C. single pole, lock-type switch manufactured by Pass and Seymour, Inc., Catalog No. ACDl1-L, gives satisfactory performance.

In FIG. 1 a cover 44 is shown for the compartment 14. After the appliance cord is connected to the socket 18, the cover 44 is placed on the ledges 45 provided therefor and is permanently fastened to the housing 12 by drive screws 46 and 48 or other suitable means. The drive screws 46 and 48 are inserted through openings 50 and 52 in the cover 44 and into holes 54 and 56 provided in the housing 12. The screws are tapped into place (as shown in FIG. 2) by a hammer or other suitable means, and once inserted cannot be removed without destroying the device. Only two screws are necessary in the illustrated embodiment because one end 58 of the cover is inserted under an overhanging portion 60 (FIG. 2) of the top of the portion of the housing adjacent the compartment 14.

Although drive screws are specifically disclosed, other suitable permanent fastening means may be employed. Also, the cover may be connected to the housing in other convenient ways than the one described hereinbefore.

While a specific embodiment of this invention has been described above, it should be understood that the invention is not limited thereto since many modifications may be made; and it is contemplated, therefore, to cover by 3 the following claims any such modifications as fall within the true spirit and scope of this invention.

What is claimed is:

1. A locking device for an electrical plug comprising:

(1) a housing;

(2) a compartment in said housing for enclosing said elcetrical plug, said compartment having an opening in one side to insert said plug;

(3) a socket in said housing adjacent said compartment adapted to receive said electrical plug;

(4) means disposed in said housing for supporting said socket;

(5) an electric line cord connected to said socket, said cord extending out of said housing through an opening therein and terminating in a plug which is adapted to be inserted into a conventional electrical outlet;

(6) a key-actuated switch in said line intermediate said socket and said line cord plug, said switch being movable between open and closed positions and being mounted in said housing with the keyhole externally accessible;

(7) means for electrically connecting said socket with said switch so that when said switch is open said socket will be disabled;

(8) means for permanently sealing said electrical plug within said housing, said means including a cover which fits over the opening in said compartment for said appliance plug and at least one fastening means which is adapted to permanently fasten said cover to said housing.

2. The apparatus of claim 1 wherein the housing has a top portion which extends part way across the top; the means for supporting said socket is a wall located intermediate the ends of said housing and under said housing top portion so that a part of said housing top portion overhangs said wall, said wall supporting said socket so that the apertures in said socket for receiving the appliance plug face the plug enclosing compartment; and the cover which fits over the opening in said compartment has one end which extends under the overhanging part of said housing top portion and has an aperture adjacent the opposite end thereof, said housing having an aperture which corresponds to the aperture in said cover,

both of said apertures being adapted to receive said permanent fastening means.

3. The apparatus of claim 2 wherein said housing and said compartment cover each have a plurality of corresponding apertures which are adapted to receive a plurality of fastening means.

4. The apparatus of claim 3 wherein said housing and said compartment cover each have two corresponding apertures which are adapted to receive the fastening means and said fastening means comprises two drive screws.

5. The apparatus of claim 1 wherein the wall located in the housing describes a second compartment in said housing, said second compartment containing said keyactuated switch and the means for electrically connecting said socket to said switch, said second compartment also containing that part of said electric line cord which is connected to said socket.

6. The apparatus of claim 5 wherein the wall has an opening through which the electric line cord passes into the plug enclosing compartment, said line cord passing out of said plug enclosing compartment through said opening in said housing for said line cord.

References Cited UNITED STATES PATENTS 1,588,984 6/1926 Nutting 200-44 X 1,656,586 I/ 1928 Hemingway ZOO-44 2,643,787 6/1953 Rockman.

2,654,073 9/ 1953 Katz.

2,733,416 1/1956 Bualt.

2,759,159 8/ 1956 Teetor.

2,761,028 8/ -6 Teetor.

2,879,494 3/ 1959 Teetor.

2,955,272 10/ 1960 Gallaudo.

3,345,603 10/ 1967 Cohen.

ROBERT K. SCHAEFER, Primary Examiner H. J. HOHAUSER, Assistant Examiner US. Cl. X.R. 200-51; 307--114

US3524029A 1968-07-22 1968-07-22 Keylock for electrical plugs Expired - Lifetime US3524029A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US74660368 true 1968-07-22 1968-07-22

Publications (1)

Publication Number Publication Date
US3524029A true US3524029A (en) 1970-08-11

Family

ID=25001539

Family Applications (1)

Application Number Title Priority Date Filing Date
US3524029A Expired - Lifetime US3524029A (en) 1968-07-22 1968-07-22 Keylock for electrical plugs

Country Status (1)

Country Link
US (1) US3524029A (en)

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4063110A (en) * 1976-01-12 1977-12-13 Glick Michael B Security device
US4135171A (en) * 1977-06-02 1979-01-16 The J. B. Foote Foundry Co. Cement mixer with switch harness
US4167658A (en) * 1978-03-20 1979-09-11 Sherman Robert S Safety and security outlet
US4247743A (en) * 1979-10-10 1981-01-27 Hinton David O Device for preventing unauthorized usage of appliance
US4323762A (en) * 1980-05-07 1982-04-06 Ervin Ron E Energy-temperature occupant monitor apparatus
DE3203925A1 (en) * 1982-02-05 1983-08-18 Triumph Adler Ag Device with strain relief to hold a ribbon cable with at least one connector
US4463228A (en) * 1983-01-07 1984-07-31 Mcgill Manufacturing Company, Inc. Portable electrical switch and outlet unit
DE3327087C1 (en) * 1983-07-27 1984-08-16 Franz Lechner Adaptor for protecting mains plugs against unauthorised apparatus use
US4479688A (en) * 1981-12-24 1984-10-30 Jennings Gordon B Wall outlet lock apparatus
US4482789A (en) * 1982-09-27 1984-11-13 Mcvey Jack L Apparatus for preventing unauthorized use of electrically powered equipment
DE3534457A1 (en) * 1985-09-27 1987-04-02 Schwoerer Artur Plug connector strip
US4828452A (en) * 1987-09-17 1989-05-09 The Gradall Company Single engine excavator capable of railroad use
GB2213331A (en) * 1987-12-04 1989-08-09 Pektron Ltd Key-operated plug to prevent unauthorised current use
US5408924A (en) * 1992-06-19 1995-04-25 Food Sciences, Inc. Apparatus for the extraction of edible oils
US5434368A (en) * 1993-10-06 1995-07-18 Hoffmann; Keith F. Apparatus for controlling use of electrically powered equipment
US5488208A (en) * 1993-10-05 1996-01-30 Seewald; Gerhard Multiple electrical outlet box with locking cover and power interrupt switch
US20090117761A1 (en) * 2000-08-09 2009-05-07 Dormina Uk Limited Electrical fitting and safety cover
US20090295327A1 (en) * 2008-05-27 2009-12-03 Mcginley Valerie L Energy-saving power adapter/charger
US20090294150A1 (en) * 2008-05-27 2009-12-03 Mcginley Valerie Energy saving cable assemblies
US20100065627A1 (en) * 2008-09-18 2010-03-18 Chris Outwater Recharge electrical apparatus and method for electric vehicles
US7960648B2 (en) 2008-05-27 2011-06-14 Voltstar Technologies, Inc. Energy saving cable assemblies
US20130003297A1 (en) * 2011-06-29 2013-01-03 Mrs. Julie Quyen Du-Henson Game Lock Box
US9531107B1 (en) * 2014-05-04 2016-12-27 Jeffrey Baldwin Tamper resistant power tap

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1588984A (en) * 1925-09-03 1926-06-15 William B Nutting Safety ignition lock
US1656586A (en) * 1922-12-20 1928-01-17 Electrolock Mfg Company Electric switch
US2643787A (en) * 1950-11-24 1953-06-30 Benjamin W Rockman Lockable container for electrical connectors
US2654073A (en) * 1950-07-29 1953-09-29 Katz Rudi Locking device for electric plugs
US2733416A (en) * 1956-01-31 Locking device for use with electrical
US2759159A (en) * 1955-03-07 1956-08-14 Herman C Teetor Electric plug with disabling means
US2761028A (en) * 1955-03-09 1956-08-28 Herman C Teetor Electric plug with disabling means
US2879494A (en) * 1955-03-09 1959-03-24 Herman C Teetor Electric plug with disabling means
US2955272A (en) * 1959-03-10 1960-10-04 Gallardo Juan Television and electric appliance lock
US3345603A (en) * 1965-09-02 1967-10-03 Cohen Stanley Alan Electrical plug key lock

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2733416A (en) * 1956-01-31 Locking device for use with electrical
US1656586A (en) * 1922-12-20 1928-01-17 Electrolock Mfg Company Electric switch
US1588984A (en) * 1925-09-03 1926-06-15 William B Nutting Safety ignition lock
US2654073A (en) * 1950-07-29 1953-09-29 Katz Rudi Locking device for electric plugs
US2643787A (en) * 1950-11-24 1953-06-30 Benjamin W Rockman Lockable container for electrical connectors
US2759159A (en) * 1955-03-07 1956-08-14 Herman C Teetor Electric plug with disabling means
US2761028A (en) * 1955-03-09 1956-08-28 Herman C Teetor Electric plug with disabling means
US2879494A (en) * 1955-03-09 1959-03-24 Herman C Teetor Electric plug with disabling means
US2955272A (en) * 1959-03-10 1960-10-04 Gallardo Juan Television and electric appliance lock
US3345603A (en) * 1965-09-02 1967-10-03 Cohen Stanley Alan Electrical plug key lock

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4063110A (en) * 1976-01-12 1977-12-13 Glick Michael B Security device
US4135171A (en) * 1977-06-02 1979-01-16 The J. B. Foote Foundry Co. Cement mixer with switch harness
US4167658A (en) * 1978-03-20 1979-09-11 Sherman Robert S Safety and security outlet
US4247743A (en) * 1979-10-10 1981-01-27 Hinton David O Device for preventing unauthorized usage of appliance
US4323762A (en) * 1980-05-07 1982-04-06 Ervin Ron E Energy-temperature occupant monitor apparatus
US4479688A (en) * 1981-12-24 1984-10-30 Jennings Gordon B Wall outlet lock apparatus
DE3203925A1 (en) * 1982-02-05 1983-08-18 Triumph Adler Ag Device with strain relief to hold a ribbon cable with at least one connector
US4482789A (en) * 1982-09-27 1984-11-13 Mcvey Jack L Apparatus for preventing unauthorized use of electrically powered equipment
US4463228A (en) * 1983-01-07 1984-07-31 Mcgill Manufacturing Company, Inc. Portable electrical switch and outlet unit
DE3327087C1 (en) * 1983-07-27 1984-08-16 Franz Lechner Adaptor for protecting mains plugs against unauthorised apparatus use
DE3534457A1 (en) * 1985-09-27 1987-04-02 Schwoerer Artur Plug connector strip
US4828452A (en) * 1987-09-17 1989-05-09 The Gradall Company Single engine excavator capable of railroad use
GB2213331A (en) * 1987-12-04 1989-08-09 Pektron Ltd Key-operated plug to prevent unauthorised current use
US5408924A (en) * 1992-06-19 1995-04-25 Food Sciences, Inc. Apparatus for the extraction of edible oils
US5488208A (en) * 1993-10-05 1996-01-30 Seewald; Gerhard Multiple electrical outlet box with locking cover and power interrupt switch
US5434368A (en) * 1993-10-06 1995-07-18 Hoffmann; Keith F. Apparatus for controlling use of electrically powered equipment
US8622759B2 (en) * 2000-08-09 2014-01-07 Dormina Uk Limited Electrical fitting and safety cover
US20090117761A1 (en) * 2000-08-09 2009-05-07 Dormina Uk Limited Electrical fitting and safety cover
US7910833B2 (en) 2008-05-27 2011-03-22 Voltstar Technologies, Inc. Energy-saving power adapter/charger
US20090294150A1 (en) * 2008-05-27 2009-12-03 Mcginley Valerie Energy saving cable assemblies
US20090295327A1 (en) * 2008-05-27 2009-12-03 Mcginley Valerie L Energy-saving power adapter/charger
US7910834B2 (en) 2008-05-27 2011-03-22 Voltstar Technologies, Inc. Energy saving cable assemblies
US7960648B2 (en) 2008-05-27 2011-06-14 Voltstar Technologies, Inc. Energy saving cable assemblies
US7984852B2 (en) 2008-09-18 2011-07-26 Liberty Plugins, Inc. Recharge electrical apparatus and method for electric vehicles
US20100065627A1 (en) * 2008-09-18 2010-03-18 Chris Outwater Recharge electrical apparatus and method for electric vehicles
US20130003297A1 (en) * 2011-06-29 2013-01-03 Mrs. Julie Quyen Du-Henson Game Lock Box
US9531107B1 (en) * 2014-05-04 2016-12-27 Jeffrey Baldwin Tamper resistant power tap

Similar Documents

Publication Publication Date Title
US3579183A (en) Signalling device to prevent leaving a key in a lock
US3139492A (en) Repositionable connector plug with position eliminator means
US3852703A (en) Modular jack strip assembly
US2792557A (en) Heavy duty electric adapters for two and three wire systems
US3585456A (en) Electric service center for mobile homes and the like
US3814834A (en) Electrical outlet box
US4319228A (en) Portable intrusion alarm
US5067043A (en) Electric power distribution panelboard-switchboard bus bar insulation shield
US5378174A (en) Enclosure for variety of terminal blocks
US5245507A (en) Weather resistant container for timer components of an irrigation system
US4995017A (en) Safety power receptacle
US3942856A (en) Safety socket assembly
US4482789A (en) Apparatus for preventing unauthorized use of electrically powered equipment
US4705342A (en) Electrical extension outlet
US2484092A (en) Remote-control adapter
US3775726A (en) Safety receptacle
US5562488A (en) Modular outlet assembly
US3971619A (en) Safe electrical connector
US2916733A (en) Cover for electric wiring and outlet
US4712157A (en) Stud mounted non-metallic electric enclosure
US6930577B2 (en) Circuit breaker lug cover and gasket
US4167658A (en) Safety and security outlet
US6132257A (en) Electrical socket device with overheating and overcurrent protection
US4059843A (en) Overload and ground fault protective device
US4404521A (en) Pilfer proofing system and method for electric utility meter box