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Publication numberUS808992 A
Publication typeGrant
Publication dateJan 2, 1906
Filing dateApr 6, 1905
Priority dateApr 6, 1905
Publication numberUS 808992 A, US 808992A, US-A-808992, US808992 A, US808992A
InventorsDaniel Lawson
Original AssigneeDaniel Lawson
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Extensible handle.
US 808992 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)



Speccation of Letters Patent.

Patented J an. 2, 1906.

Application tied .iprii 6, 1905. semi No. 254,248.

To @ZZ whom t may concern:

Be it known that I, DANIEL LAWSON, a citizen of the United States, and a resident of the city of New York, borough ofthe Bronx, in the county and State of New York, have invented a new and Improved Extensible Handle, of which the following is a full, clear, and exact description.

My invention relates to extensible handles-such, for instance, as are used upon shovels and analogous implements for handling coal, and also admitting of general use in instances where longitudinal cylindrical handles areemployed. 1

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the figures.

Figure 1 is an elevation, partly in section, showing my improved handle as applied to a coal-shovel. Fig. 2 is an enlarged cross-section upon the line 2 2 of Fig. 1 looking in the direction of the arrow and showing the positions of the several parts when the telescopic members are locked rigid relatively to each other g and Fig. 3 is a view similar to Fig. 2, with the exception that the telescopic lportions are shown as unlocked, so that the length of the handle may be changed.

The bowl of the shovel is shown at 41 and is provided with a cylindrical portion 5, extending therefrom, this portion being secured by means of rivets 6 upon a tubular member 7, made, preferably, of steel and provided at its upper end with an annular portion 8, which is comparatively thick. A tube 9 is provided with an annular head 10, also comparatively thick, and with a pair of oppositely-disposed slots 11. Encirchng the tube 9 and partially encircling the tubular member 7 is a third tube 12, provided at its lower end with a comparatively thick annular portion 13. The hand-grip 14 is mount- .ed within the fork 15, which terminates in a neck 16, as indicated in the upper portion of Fig. 1. A cylindrical rod 17, preferably of steel, is provided at its lower end with oppositely-disposed cam-lobes 18 and -is revolu ly mounted within the neck 16. The upper end of this rod is provided with a crank portion 19, having a thumb-piece 20 integral therewith and adapted to move into the p0- sition indicated by dotted lines in Fig. 1. A screw 20a passes through the wall of the tube 12 and the thick annular head 10 of the tube 9, so as to penetrate the stem 16, as indicated in Fig. 1. The tube 9 at its lower end and upon opposite sides of the head 10 is provided with thickened portions 9a, which serve as cam-lobes, as will be understood from Figs. 2 and 3. An annular bead 18:L is carried by therod 17 and integral therewith. This rod 17 is, in effect, a rocking stem actuated by means of the crank portion 19 and the thumb-piece 20. The inner and outer tubes 9 and 12 and the intermediate tube 7, together with their accompanying parts, constitute the handle.

The operation of my device is as follows: When the operat`or`desires to render the handle comparatively short, he turns the crank portion 19 into the position indicated by dotted lines in Fig. 1, or, in other words, gives it a quarter-turn, and then pushes upon the hand-grip 14, so as to drive the annular portion 8 of the tube 7 to a point adjacent to the annular h'ead 10, preferably resting against the same. He then restores the crank ortion 19 to the position indicated by'full lines in Fig. 1. The movement of the crank portion 19 into the position indicated by dotted lines causes the cam-lobes 18, carried by the rocking stem 17, to relax their grip against the cam-lobes 9a, as will be understood from Fig. 3. When, therefore, thev crank portion 19 is restored to its position, (indicated by full lines in Fig. 1,) the cam-lobes 18 of the stem 17 are forced into firm engagement with the cam-lobes 9a of the tube 9 and cause the lower end of this tube to swell and rigidly lock against the inner surface of the tube 7. This renders the handle rigid. To lengthen or shorten the handle to any desired extent, the crank portion 19 is moved, as above, into the position indicated by dotted lines in Fig. 1, the tube 7 being drawn out or in to the desired extent, and the crank portion 19 again restored to its position. (Indicated by full lines.)

It will be noted that the annular portion 13 of the tube 12 is at all times in the same plane as the cam-lobes 18 and 9, so that the strain due to the gripping action of the cams is taken up by the annular portion 13, which is to all intents and purposes a steel b and possessing great strength.

The operator can, if he so desires, change the length of the handle at comparatively short intervals and can maintain the upper .lOO

end of the tube 7 comparatively cool by so doing-that is to say, each time the handle is extended a comparatively cool portion of the tube 7 is presented below the annular portion 13 and this cool portion may be grasped by the operator without danger of burning his hands. In other words, the upper end of the tube 7 may be momentarily protected by the outerl tube l2 if the operator uses the shovel for a few moments in such relation as would ordinarily cause the heating of the tube 7 if fully extended.

The telescopic action of the handle is accomplished without materially weakening the handle, for the reason that the construction above described possesses adequate strength Jfor all ordinary purposes.

Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. The combination of a fork, a hand-grip mounted therein, an inner tube provided with an annular portion encircling a portion ofsaid fork, an outer tube encircling said inner tubeand spaced therefrom by said annular portion, a telescopic member disposed intermediate of said inner and outer tubes and free to slide relatively thereto, and means for locking said telescopic member rigidly in relation to said inner and outer tubes.

2. The combination of a fork, telescopic members connected therewith, one oit' said telescopic members being provided with camlobes, a rocking stem mounted within said fork and provided with cam-lobes mating said iirst-mentioned cam-lobes, and means controllable by hand for causing said stem to rock.

3. The combination of telescopic tubular members adapted to slide relatively to each other, one of said members being provided with cam-lobes, a rocking stem disposed within said tubular members and provided with cam-lobes mating the cam-lobes iirst mentioned, means controllable at will for turning said rocking stem so as to force all of the cam-lobes into locking engagement, and a member connected with one of said tubular members and provided with a hand-grip.

4. The combination of an inner tube provided with a bowl or the like, an outer tube encircling said inner tube and slidable relatively thereto, said outer tube being provided with a handle portion, a revoluble member mounted centrally within said inner tube and adapted to be turned at will by hand and cam mechanism operated by said revoluble member Jfor securing said inner and outer tube rigidly together.

5. The combination of an inner' tube provided with a bowl or the like, an outer tube partially encircling said inner tube and slidable relatively thereto, and means for temporarily securing said outer tube and said inner tube rigidly together.

In testimony whereor` I have signed my name to this specification in the presence of two subscribing witnesses.


. Witnesses:


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2529342 *Apr 19, 1948Nov 7, 1950Kopplin Clarence LExtension handle for shovels and the like
US2873129 *Aug 29, 1955Feb 10, 1959Tubelock CompanyLock for telescopic connections
US3095825 *Jul 10, 1961Jul 2, 1963Rudolf BalzerLocking mechanism for telescoping members
US3235296 *May 18, 1962Feb 15, 1966Day Robert CExtensible and retractible implement handle
US3259407 *Aug 28, 1963Jul 5, 1966Safe Lock IncLock for telescoping tubes
US3808633 *Mar 2, 1972May 7, 1974Trola GmbhFurniture fitting, specifically for detachable suspension of a sliding door from a guide rail
US4333357 *Jun 6, 1980Jun 8, 1982Knud VintherExpansion element
US4347758 *Sep 3, 1980Sep 7, 1982Gould Inc.Molded plastic control lock knob
US4373405 *Sep 3, 1980Feb 15, 1983Gould Inc.Molded plastic control lock knob with push and/or pull feature
US5951078 *Oct 6, 1997Sep 14, 1999Suncast CorporationExpandable snow tools for vehicles
US8167616Mar 12, 2010May 1, 2012Hu-Friedy Mfg. Co., LlcDental handpiece system with replaceable treatment tips
US8182168 *Aug 12, 2008May 22, 2012GM Global Technology Operations LLCMachine element for a shaft-hub connection and manufacturing method for a shaft-hub connection
Cooperative ClassificationB25G3/02