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Publication numberUS3668344 A
Publication typeGrant
Publication dateJun 6, 1972
Filing dateMay 4, 1970
Priority dateMay 4, 1970
Publication numberUS 3668344 A, US 3668344A, US-A-3668344, US3668344 A, US3668344A
InventorsLehmann Herbert G
Original AssigneeLehmann Herbert G
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Quick replacement, slack take-up electric cord with improved switch, detachable electrical connector means
US 3668344 A
Abstract
A quick replacement, slack take-up electric cord for lamps, clocks, radios, etc, comprising a length of two-conductor lamp cord coiled and permanently set in a helix, one end of the lamp cord having a conventional two-prong electric plug for insertion in a wall receptacle. The other end of the cord has a special elongate receptacle made with a recess at the end opposite to the entrance of the cord. The receptacle has a push-button switch and a flat base for support on a table surface. Within the receptacle are two metal connector pieces having sharp prongs located at the inner end of the recess. The recess is oblong in cross sectional configuration to receive a freshly cut end portion of the original electric cord from the appliance, where it has been cut close to the appliance. The receptacle also has a manually operable lever to force the said cut end of the appliance cord laterally against the prongs so as to make electrical connection thereto. Replacement of an old cord involves merely cutting the cord an inch or so from the appliance, inserting the cut cord end deeply in the receptacle recess and then operating the lever to impale the cord on the sharp prongs. The plug of the replacement cord is then inserted in the wall receptacle. The receptacle switch will now be conveniently accessible to switch the appliance on and off.
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Description  (OCR text may contain errors)

United States Patent Lehmann Herbert G. Lehmann, 5 Kent Road, Easton, Conn. 06612 [22] Filed: May4, 1970 [21] Appl.No.: 34,324

[72] Inventor:

[52] US. Cl ..200/52 R, 339/103 R [51] Int. Cl. ..HOlh 35/00 [58] Field of Search ..200/51, 52; 339/28, 95, 96, 339/103, 147, 200, 208

[56] References Cited UNITED STATES PATENTS 1,336,290 4/1920 Finkelstein ..339/206 X 1,826,576 10/1931 Rum ..200/51 R X 2,197,910 4/1940 Ament.. ..339/28 X 2,261,419, 11/1941 Shann ..200/51 R 2,680,145 6/1954 Lanfear.... ..339/103 X 3,179,916 4/1965 Larson ...339/200 X 3,437,981 4/1969 Keller ..339/103 3,452,150 6/1969 Gazzoli ..339/103 X 1 1 June6,1972

Primary ExaminerJ. R. Scott AttorneyH. Gibner Lehmann [57] ABSTRACT A quick replacement, slack take-up electric cord for lamps, clocks, radios, etc, comprising a length of two-conductor lamp cord coiled and permanently set in a helix, one end of the lamp cord having a conventional two-prong electric plug for insertion in a wall receptacle. The other end of the cord has a special elongate receptacle made with a recess at the end opposite to the entrance of the cord. The receptacle has a pushbutton switch and a flat base for support on a table surface.

Within the receptacle are two metal connector pieces having sharp prongs located at the inner end of the recess. The recess is oblong in cross sectional configuration to receive a freshly cut end portion of the original electric cord from the appliance, where it has been cut close to the appliance. The receptacle also has a manually operable lever to force the said cut end of the appliance cord laterally against the prongs so as to make electrical connection thereto. Replacement of an old cord involves merely cutting the cord an inch or so from the appliance, inserting the cut cord end deeply in the receptacle recess and then operating the lever to impale the cord on the sharp prongs. The plug of the replacement cord is then inserted in the wall receptacle. The receptacle switch will now be conveniently accessible to switch the appliance on and off.

5 Claims, 7 Drawing Figures PATENTEDJun 61972 sum 10F 2 5 wis @N mm 3&8 mm o mm 440v? w FY 68 SHEET 20F 2 PATENTEDJun 61912 Ow vii?! 3 om/ wk 2$ IN V EN TOR. 4. LEHMANN T H 5 m H QUICK REPLACEMENT, SLACK TAKE-UP ELECTRIC CORD WITH IMPROVED SWITCH, DETACHABLE ELECTRICAL CONNECTOR MEANS CROSS REFERENCES 1. Copending application of Herbert G. Lehmann, Ser. No. 28,762, filed Apr. 15, 1970, and entitled Quick Replacement, Slack Take-Up Electric Cord for Lamps, Radios, Clocks and the Like," and having the same ownership as the present application. BACKGROUND This invention relates to replacement electric cords for small electric appliances such as lamps, clocks, radios, and the like.

The present invention is a continuation-in-part of my copending application, Ser. No. 28,762, filed Apr. 15, 1970, and entitledQuick Replacement, Slack Take-Up Electric Cord for Lamps, Radios, Clocks and the Like.

I-Ieretofore the procedure in replacing an electric cord for a lamp, radio or clock required dismantling the device and removing the old electric cord therefrom. A new length of lamp cord or the like was then connected to the interior circuit of the device and threaded through the channels provided, and a two-prong plug was attached to the free end of the new cord. This procedure was not only time-consuming but it required a considerable amount of skill. For example, the radio or clock casing would have to be opened, or in the case of a lamp, the base and pedestal portion would have to be dismantled to enable the old cord to be pulled out and the new cord to be threaded in. Electrical connections, often involving soldering, would have to be made to the circuitry of the radio or clock, or to the sockets of the lamp. In most circumstances it was found that the original electric cord of the appliance at those locations within the casing or lamp pedestal, as the case may be, was perfectly sound and actually did not need replacement. Replacement was desired because of fraying of the external portions of the cord, or because the external portions became dirty, discolored or dried out and brittle. In most cases, the replacement procedure as set forth above had to be made by a competent electrician or radiotrician, or else a skilled handyman, and this was a distinct disadvantage in that it precluded quick replacement as well as easy replacement such as could be made by a housewife, for example. Most lamps have their switches incorporated in the socket shell, whereby the user must reach up within the lamp shade and either pull a chain or push a button to operate the lamp. This is not nearly as convenient as having a switch at the base of the lamp; in fact, the lamp-socket-contained switch is often very inconvenient to use.

SUMMARY The above disadvantages and drawbacks of prior switching arrangements in lamps, radios, and the like, and prior replacement of original or old electric cords in lamps, clocks, radios and the like are obviated by the present invention, which has for one object the provision of a novel and improved quick replacement electric cord which may be virtually instantly installed to replace the frayed, discolored or worn cord of a light-duty appliance. Another object of the invention is to provide an improved replacement electric cord as above set forth, which has an inherent slack take-up or helical formation whereby it is stretchable from a relatively short length to a much greater length, and whereby it normally automatically takes up slack, making it unnecessary to employ reeling or cord storage links or the like as heretofore utilized.

Still another object is to provide an improved replacement electric cord as above characterized, which has incorporated with it an integrally'arranged push button switch that will be located closely-adjacent the appliance and on the adjoining table surface, thereby to make the operation of the appliance more convenient.

The foregoing objects are accomplished by a replacement electric cord comprising'a'length of two-conductor insulated wire having attached to one end a conventional two-prong electric plug. The other end of the length of wire carries a special receptacle fitting which may have a push-button switch or may be devoid of any switches; said special receptacle having a socket of substantially oblong cross-sectional configuration, and having a pair of contact prongs at the inner end of the socket, adapted to laterally pierce the inserted, freshly cut end portion of a flat appliance cord as usually provided on lamps, clocks, radios and the like. Manually operable means such as a cam lever is provided, to force the cut end of the flat appliance cord against the prongs whereby the cord is impaled thereon, enabling the prongs to electrically connect with the conductors of the cut flat cord. The prongs are electrically connected with the two-conductor length of wire making up the quick replacement cord. Thus, the procedure for replacing the worn appliance cord involves merely cutting the worn cord at a point one or two inches from the appliance and inserting the freshly cut remaining end in the socket of the receptacle fitting of the replacement cord. The cam lever is then operated to lock the cut end portion in place and cause it to be impaled on the connector prongs. This entire operation can be done in several seconds, and requires no skill whatsoever since the average housewife can carry out the procedure after reading appropriate simple directions telling her to cut off the old cord at a point one or two inches from the casing or lamp pedestal, and thereafter to insert the remaining cut cord portion in the socket, lastly actuating the lever to lock the appliance cord in place and thus simultaneously effect the electrical connections. If the special receptacle has a push-button switch, it also is preferably provided with a flat base to set on the adjoining table surface, adjacent the appliance. Thus the user can turn the appliance on or off at a more convenient and readily accessible location.

Still other objects and advantages of the invention reside in the provision of an improved replacement electric cord as above characterized, which is especially simple and inexpensive to produce, and wherein the receptacle fitting comprises relatively few parts which may be economically fabricated and assembled, thereby keeping the entire manufacturing cost of the replacement cord to a low figure; and the provision of a helically coiled replacement electric cord arranged to be stretchable so as to take up slack without involving supplemental parts such as reels, takeup links and the like, wherein the helical configuration while inherent in the plastic insulation can take a set" after the final installation, thereby relieving undesired tensions which could pull a light-duty appliance out of place.

Other features and advantages will hereinafter appear.

In the accompanying drawings, illustrating one embodiment of the invention:

FIG. 1 is a view partly in side elevation and partly in axial section of a replacement electric cord installed on an electric lamp, the latter being shown in partial section.

FIG. 2 is a side elevational view of the receptacle fitting portion of the replacement electric cord.

FIG. 3 is an axial sectional view taken on the line 3-3 of FIG. 1.

FIG. 4 is an end view of the receptacle fitting of the replacement cord, with the original appliance conductor shown in transverse section. The section is taken on the line 44 of FIG. 3.

FIG. 5 is a view partly in side elevation and partly in axial section, of a replacement electric cord having a push-button switch and constituting another embodiment of the invention, said replacement cord being installed on an electric lamp which is shown in partial section.

FIG. 6 is a side elevational view of the special receptacle and switch fitting of the replacement cord of FIG. 5.

FIG. 7 is an axial sectional view taken on the line 77 of FIG. 6.

Referring now to the figures, the present improved replacement electric cord comprises a length of two-wire conductor 10 which in accordance with the invention is preferably although not necessarily coiled into a helical configuration and nonnally has only a slight tendency to return to its helical shape after considerable stretching. Such tendency may be inherent in the plastic insulation of the cord if it is formed of extruded plastic material and given the helical configuration before the plastic has fully set. Or, ordinary lamp cord may be wound tightly around a /8 inch mandrel rod, the wire opening up to approximately a /2 inch coil after winding. By this latter procedure an improved product is had, since the coiled wire after being stretched will take a set in a new position and will not maintain appreciable constant tension which otherwise might dislodge a light-duty appliance, such as a clock or small lamp.

Secured to one end of the stretchable cord 10 is a conventional two-prong electric plug 12 having prongs or blades 14 which are continuously electrically connected to the two conductors of the cord 10 in the usual manner.

Further, in accordance with the present invention, the other end of the cord 10 is provided with a novel elongate, hollow receptacle fitting 16 having an end portion 18 in which the cord 10 is received, the other end portion of the fitting l6 having a socket 20 of substantially oblong cross sectional shape, being adapted to receive the end of a flat lamp cord shown at 22. The lamp cord 22 is the original cord of the lamp designated generally by the numeral 24, said lamp having a pedestal portion 26 and a base portion 28, together with a conduit or pipe 30 passing through the pedestal and base portions and carrying a nut 32. The original lamp cord 22 passes through the conduit 30, and passes out through an opening 34 in a side wall 36 of the base 28.

As provided by the invention, the receptacle 16 has a pair of prong contacts 38, said prong contacts having base portions 40 to at least one of which an individual conductor 42 of the cord 10 is continuously electrically connected. As seen in FIGS. 1 and 3, both conductors 42 of the cord 10 are continuously electrically connected to the prong contacts 38. In another embodiment of the invention, described below, only one of the conductors 42 is continuously connected to a contact 38. The prong contacts 40 are separated by an insulating slab 44, said prong contacts having sharp points 46 extending into the socket 20 of the receptacle at the bottom or inner end thereof. The outer end of the socket 20 is seen to be open at the exterior of the fitting 16, whereas the inner end of the socket is disposed in the interior of the fitting, that is, nearer to the fitting end 18 than other areas of the socket. Spaced from the sharp points 46 is a projecting wall 48 in the socket 20, and pivotally carried opposite the points 46 is a cam lever 50 which is movable about a pivot pin 52, said lever having a handle portion 54.

The lever 50 has a camming portion 56 which is removed from the socket 20 when the lever is in the raised position illustrated in FIG. 2. However, when the lever is swung counterclockwise from the position of FIG. 2 to the closed position of FIG. 1, the camming portion 56 of the lever will press against the inserted freshly cut end portion of the original lamp cord 22, causing the latter to be forced against the points 46 of the prong contacts 38 whereby the lamp cord is impaled on the prongs. The two prongs 46 will pierce the insulation of the cord 22 and make electrical contact with the conductors thereof. Since the prong contacts are connected with the conductors 42 of the replacement cord 10, a complete electrical circuit will be established between the replacement cord 10 and the original lamp cord 22. It will be understood that as the lever 50 is swung to its closed position, the inserted end of the original lamp cord 22 would be somewhat bent around the projection 48 of the receptacle casing, and a secure locking action will be had inasmuch as the counterclockwise turning of the lever 50 is halted when it reaches the position of F IG. 1. Any pulls on the lamp cord 22 will merely serve to more securely impale the cord on the prongs 46 and lock it between the projection 48 and the tip of the camming portion 56 of the lever.

The receptacle fitting 16 may be advantageously constituted of two halves 58, 60 formed of molded plastic, said halves being secured together by small rivets 62.

Another embodiment of the invention is illustrated in FIGS. 5, 6 and 7 wherein the special receptacle fitting 160 has a push-button switch to control the circuit of the appliance.

The replacement cord 10a has a conventional plug 12a with prongs 14a to be inserted in a wall receptacle. The fitting 16a has molded casing halves 66, 68 provided with base flanges 70, 72 respectively. Prong contacts 74 and 76 are provided in the casing 66, 68 having sharp prongs 78, 80 respectively, for imbedment in the appliance cord 22 under the action of a cam lever 82. The prong contact 76 has an olT-set extremity 84 which is engageable by a leaf-spring or blade contact 86 secured to the casing half 68 by a drive pin 88. One conductor of the coiled cord 10a is electrically connected to the blade 86, said blade being normally biased away from and out of contact with the extremity 84 of the prong contact 76. The other conductor of the cord 10a is connected to the prong contact 74.

A push-button 90 is vertically movable in a guide opening 92 in the casing halves 66, 68. The button 90 has a shoulder 94 engageable with the underside of the top wall 96 of the casing to maintain the button depressed whereby it forces the bend of an angular portion 98 of the blade 86 into engagement with the extremity 84 of the prong contact 76, closing the circuit as shown. If the button 90 is rocked clockwise from the FIG. 5 position it will be shifted upward by the blade 86, which then opens the circuit. A projection 100 on the button 90 engages the wall 96 to hold the button captive. s

It will now be understood from the foregoing that replacement of a worn electric cord of a lamp, radio, clock or the like involves merely cutting off the original cord at a point one or several inches from the casing or base of the appliance, and inserting the remaining freshly cut end into the socket 20 with the lever 50 in the raised position, as illustrated in FIG. 2. Thereupon the lever 50 is swung closed to the position of FIG. 1 whereby the replacement is completed. The electrical connections between the original cord 22 and the replacement cord 10 will be made automatically as the insulation of the cord 22 is pierced by the points 46 of the prong contacts 38. The entire installation procedure maybe effected in a matter of seconds, and may be done by an unskilled person such as a housewife. The coiled configuration of the replacement cord 10 provides a very neat appearance, and eliminates unsightly excessive lengths of cord from being disposed along the floor or other parts of the room.

By the provision of the switch illustrated in FIGS. 5-7, the appliance can be most conveniently turned on or off. The base flanges 70, 72 of the receptacle rest on the adjoining table surface and provide a stable foundation which facilitates the operation of the push-button.

Variations and modifications are from the spirit of the invention.

I claim:

1. As a new article of manufacture, a replacement electric cord for small appliances such as lamps, radios, clocks and the like, comprising in combination:

a. a length of all-one-piece two-conductor electric cord,

possible without departing b. a two-prong electric plug affixed to one end of said electric cord and having prong-type contacts continuously electrically connected respectively to the conductors of the cord,

c. an electric receptacle fitting attached to the other end of the electric cord, said receptacle fitting having an openended socket of substantially oblong cross-sectional configuration for receiving the cut end portion of a similarsection all-one-piece cord of the appliance, said socket having an outer end which is open at the exterior of the fitting and having an inner end disposed in the interior of the fitting,

(1. said receptacle fitting having a "pair of sharp prongs disposed at the said inner end of the socket, at least one of said prongs being continuously electrically connected to one of the conductors of said two-conductor cord, the other of said prongs being connectable to the other conductor of the cord, and

e. exposed and accessible, manually operable lever and cam means carried by the receptacle fitting and adapted to force laterally against the sharp prongs the one-piece end portion of a cut electric cord of an appliance when said end portion is inserted in said socket, whereby both the prongs pierce the insulation of the inserted appliance cord end and make electrical contact respectively to the conductors thereof,

f. switch means carried by said receptacle fitting, and

g. connections between said switch means and the electric cord and a prong of the fitting for controlling the electrical circuit of the appliance.

2. A replacement electric cord for small appliances such as lamps, radios, clocks and the like, comprising in combination:

a. a length oftwo-connector electric cord,

b. a two-prong electric plug affixed to one end of said electric cord and having prong-type contacts electrically connected respectively to the conductors of the cord,

c. an electric receptacle fitting attached to the other end of the electric cord, said receptacle fitting having a socket of substantially oblong cross-sectional configuration for receiving the cut end portion of a similar-section cord of the appliance,

d. said receptacle fitting having a pair of sharp prongs disposed at the inner end of the socket and electrically connected respectively to the conductors of said two-conductor cord, and

e. manually operable means carried by the receptacle fitting and adapted to force laterally against the sharp prongs the end portion of a cut electric cord of an appliance when said cord is inserted in said socket, whereby the prongs pierce the insulation of the inserted appliance cord and make electrical contact to the conductors thereof,

f. switch means carried by said receptacle fitting, and

g. connections between said switch means and the electric cord and a prong of the fitting, for controlling the electrical circuit of the appliance,

h. said switch means comprising an upstanding push-button and an electrical contact actuated by the push-button, and

i. a base carried by the receptacle fitting, adapted to rest on a table surface adjacent the appliance, thereby to facilitate actuation of the push-button.

3. A replacement electric cord as defined in claim 2, and

further including:

a. cooperable releasable latch means on the push-button and receptacle fitting, for maintaining the push-button in a depressed position, and

b. means biasing the push-button to a raised, non-depressed position on the receptacle fitting.

4. A replacement electric cord as defined in claim 3,

wherein:

wherein:

a. one of said sharp prongs has a base portion constituting a switch contact which is cooperable with said switch blade.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1336290 *Feb 8, 1919Apr 6, 1920Finkelstein Morris FElectrical fitting
US1826576 *Feb 1, 1930Oct 6, 1931 Lighter fob
US2197910 *May 29, 1939Apr 23, 1940Ament Harry AElectric razor apparatus
US2261419 *Aug 26, 1939Nov 4, 1941Bell Telephone Labor IncElectric switch
US2680145 *Jul 10, 1951Jun 1, 1954Lanfear Joseph PWire connector
US3179916 *Apr 8, 1963Apr 20, 1965Larson Magnus CElectric plug
US3437981 *Jun 29, 1967Apr 8, 1969Keller Robert JosephElectrical wire joiner
US3452150 *May 4, 1966Jun 24, 1969Alfred A MazzocchiConnection device and insulator for electric wiring
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4081641 *Nov 26, 1976Mar 28, 1978Cutler-Hammer, Inc.Toggle switch with hinged split housing and insulation piercing contacts
Classifications
U.S. Classification200/52.00R, 439/409
International ClassificationH01R4/50, H01H13/00
Cooperative ClassificationH01H13/00, H01R4/50
European ClassificationH01R4/50, H01H13/00