US3284114A

US3284114A - Telescoping pole

Info

Publication number: US3284114A
Application number: US391153A
Authority: US
Inventors: Jr Wilfred M Mccord; Walter J Williford
Original assignee: Vermont American Corp
Current assignee: Robert Bosch Tool Corp
Priority date: 1964-08-21
Filing date: 1964-08-21
Publication date: 1966-11-08
Anticipated expiration: 1983-11-08

Description

Nov. 8, 1966 w. M. MCCORD, JR. ETAL 3,284,114

TELES COPING POLE Filed Aug. 21, 1964 FIG.

FIG. 3 60 Y INVENTORS WILFRED M. McCORD,JR. WALTER J. WILL/FORD BY I 3 yufllm, 3M v (7M ATTYS.

United States Patent 3,284,114 TELESCOPING POLE Wilfred M. McCord, Jr., Louisville, and Walter J. Williford, Pleasure Ridge Park, Ky., assignors to Vermont American Corporation, Louisville, Ky., a corporation of Kentucky Filed Aug. 21, 1964, Ser. No. 391,153 4 Claims. (Cl. 287-58) The present invention relates to a telescoping pole for use as a handle for a pruning saw or other such instrument as requires a long handle for use at a substantial distance from the operator. More specifically, the invention relates to a pole comprising upper and lower telescoping pole sections which can be moved relative to one another to determine the overall length of the pole and which can be locked in a desired position.

It is an object of the present invention to provide an improved telescoping pole which is relatively inexpensive to manufacture and yet is efficient and durable in use and can be locked and unlocked with light hand pressure.

Now in order to acquaint those skilled in the art with the manner of constructing and utilizing the telescoping pole of the present invention, we shall describe in conjunction with the accompaying drawings a preferred embodiment of the invention.

In the drawings:

FIGURE 1 is an elevational view, partly in section and partly broken away, showing a telescoping pole constructed in accordance with the present invention and having an upper pole section telescoped within a lower pole section and locked in a predetermined relative position therein by means of an elastic collet or ferrule;

FIGURE 2* is an enlarged fragmentary longitudinal section view showing the collet structure for releasably locking the two telescoping pole sections in a predetermined relative position;

FIGURE 3 is a detail plan view of the elastic collet or ferrule which serves as a locking member for holding the telescoping pole sections in a fixed position relative to one another; and

FIGURE 4 is an elevational view of the collet of FIGURE 3.

Referring now to the drawings, there is shown a telescoping pole 20"comprising an upper extension 22 and a lower extension 24. The upper and lower extensions 22 and 24 'both comprise aluminum tubes, and the outer diameter of the upper tube 22 is less than the inner diameter of the lower tube 24, the upper tube being telescoped Within the lower tube and being movable therein in order to vary the overall length of the pole 20.

FIGURE 2 shows a steel sleeve 26 having an upper portion 28 which is externally threaded and having a lower sleeve portion 30 which fits over the upper end of the lower extension 24. The sleeve 26 is provided with an internal annular shoulder 32 which seats against the upper and of the lower extension 24, and the sleeve is bonded to the lower extension by means of epoxy cement. The upper end of the sleeve 26 is provided with an internal annular bevel 34 which extends upwardly and outwardly and is inclined at an angle of approximately 30 degrees to the axis of the pole 20, and there is formed at the upper end of the bevel 34 a short annular surface 36 which is parallel to the axis of the pole.

A nut 38 has a lower end portion 40 which is internally threaded 'and an upper portion 42 which is provided with an internal annular bevel 44 which extends downwardly and outwardly and defines an angle of approximately 30 degrees with the axis of the pole, there being at the lower end of the bevel 44 a short annular surface 46 which is parallel to the pole axis and which has a diameter approximately equal to the diameter of the annular surface 36. Since the beveled surface 34 on the sleeve 26 is inclined upwardly and outwardly while the beveled surface 44 on the nut40 is inclined downwardly and outwardly, when the nut 40 is threaded over the upper end of the sleeve 26 the inclined

annular surfaces

34 and 44 define a chamber of variable length for retaining a collect or ferrule 48. The outer surface of the nut 38' is knurled to facilitate turning the same on the sleeve 26.

The collet or ferrule 48 may be manufactured as a continuous helical member having the desired cross section, and then a section such as shown in FIGURES 3 and 4 may be cut therefrom to form the collet 48, the latter being in the approximate form of a split ring and having free end portions which may be spaced apart approximately /s to inch for a collet having an outer diameter of approximately 1 inches. The collet 48 has an annular inner surface 50 which is parallel to the axis of the pole 20, and the oollet is positioned in the chamber defined between the

inclined surfaces

34 and 44 so as to substantially encircle the upper pole extension 22. The outer surface of the collet 48 comprises an intermediate annular surface 52 which is parallel to the pole axis, and a pair of upper and] lower

inclined cam surfaces

54 and 56 which bear against the

inclined surfaces

44 and 34 respectively. That is, the upper annular collet surface 54 is inclined downwardly and outwardly at an angle of approximately 30 degrees to the pole 'axis in order to correspond with the inclination of the inner surface 44 on the nut 38, and the lower annular collet surface 56 is inclined upwardly and outwardly at an angle of approximately 30 degrees to the pole axis in order to correspond with the inclination of the inner surface 34 on the sleeve 26. The collet 48 is seated against the upper end of the sleeve 26 with the collet surface 56 engaged against the sleeve surface 34, and the nut 38 is threaded on the upper end of the sleeve so as to cause the nut surface 44 to bear against the collet surface 54.

When in its free state the collet 48 is expanded to'its maximum diameter as shown in FIGURES 3 and 4, and the collet is compressed so as to tighten the same around the outside of the upper extension '22 when the nut 38 is threaded downwardly on the sleeve 26. The collet 48 is elastic and will expand so as to release the upper extension 22 when the nut 38 is again threaded upwardly on the sleeve 26. In the foregoing manner the upper extension 22 may be releasably locked in any position relative to the lower extension by simply locating the upper extension in the desired position and turning the nut 38 a small amount in order to thread it downwardly on the sleeve. Since the upper tubular extension 22 is made of aluminum, the collet 48 which clamps the extension should preferably be made of a material which is softer than aluminum in order to avoid marring. In addition, the collet must be elastic so that it will expand and release the upper extension 22 whenever the nut 38 is threaded upwardly on the sleeve 26. We have found that relatively rigid vinyl plastic is well suited for the fore-going purposes, and thus the collet 48 is preferably made from extruded rigid vinyl, although nylon or other plastic materials may be used in certain applications.

The telescoping pole of the present invention is particularly well suited as an extendable handle for a pruning saw, although it will be understood that it is suitable for numerous and varied other applications where a tool or cut-ting implement or the like requires a long extendable handle which can be adjusted to a desired length and then releasably locked in position. FIGURE 1 shows an insulating sleeve 60 which is secured on the outside of the lower extension 24 and which is folded up into 3 the interior of the extension at the lower end thereof a shown at 62.

While We have described our invention in a preferred form, we do not intend to be limited to that form, except insofar as the appended claims are so limited, since various modifications within the scope of the present invention will readily occur to those skilled in the art, particularly with our disclosure before them.

We claim:

1. A telescoping pole for use with a pruning saw or the like comprising, in combination, an upper tubular pole extension, a lower tubular pole extension having an inner diameter greater than the outer diameter of said upper pole extension, said upper extension being telescoped within said lower extension, an externally threaded member disposed at the upper end of said lower pole extension and fixed relative to the latter, an upper inner portion 'of said threaded member being formed as a first annular tapered surface extending upwardly and outwardly, a nut member threaded on the upper end of said threaded member, said nut member being rotatable on said threaded member for adjusting the relative axial position of said nut member and said threaded member, a second annular tapered surface formed internally on said nut member proximate the upper end thereof, said second annular tapered surface extending downwardly and outwardly and being disposed above said first annular tapered surface so as to define therebetween a chamber of variable axial length determined by the relative axial position of said nut member on the threaded member, and an elastic helical collet shaped approximately as a split ring with axially spaced ends when in an unconfined state, said collet having upper and lower annular inclined surfaces formed on the outside thereof for engagement with said first and second annular surfaces respectively of the nut and threaded members which define a chamber of variable axial length, said collet being positioned within said chamber so as to substantially encircle said upper pole extension and being seated against said first annular tapered surface between the latter and said second annular tapered surface on said nut member, whereby said upper tubular extension may be releasably locked in position relative to said lower tubular extension by threading said nut downwardly on said threaded member so as to decrease the axial length of said chamber and deform the elastic collet from its initial helical to a more nearly circular shape and thereby cause said collet to be clamped between said first and second annular tapered surfaces and to tightly engage said upper extension to hold said upper extension against axial movement relative to the lower pole extension.

2. A telescoping pole for use with a pruning saw or the like comprising, in combination, an upper tubular pole extension, a lower tubular pole extension having an inner diameter greater than the outer diameter of said upper pole extension, said upper extension being telescoped within said lower extension, an externally threaded sleeve positioned over the upper end of said lower extension and fixedly secured to the latter, an upper inner portion ,in a first cylindrical surface, a nut member threaded on the upper end of said sleeve, said nut member being rotatable on said sleeve for adjusting the relative axial position of said nut member and said sleeve, a second annular tapered surface formed internally on said nut member proximate the upper end thereof, said second annular tapered surface extending downwardly and outwardly and terminating in a second cylindrical surface disposed above said cylindrical first surface so as to define a chamber of an axial length variable with the rotation of the nut member on said sleeve, and an elastic plastic collet shaped approximately as a split, helical ring having axially displaced spaced ends in its relaxed state, said ring having upper and lower annular tapered inclined surf-aces formed on the outside thereof for engagement with said first and second annular tapered surfaces respectively, an intermediate surface between its upper and lower annular inclined surfaces for engagement with the first and second cylindrical surfaces of the sleeve and nut member and an inner cylindrical urface about said upper pole extension, said collet being normally positioned between said first annular tapered surface and said second annular tapered surface on said nut member, whereby said upper tubular extension may be releasably locked in position relative to said lower tubular extension by threading said nut downwardly on said sleeve thus to decrease the axial length of said chamber thereby clamping said collet between said first and second annular tapered surfaces tand deforming it from a helical to a more nearly circular shape thereby to cause its inner cylindrical surface to tighten around said upper extension and hold the same against axial movement in the lower pole extension.

3. The invention of claim 2 wherein said upper and lower tubular pole extensions are made of aluminum and said collet is made of relatively rigid vinyl plastic.

4. The invention of claim 2 wherein said sleeve has an internal annular shoulder which is seated against the upper end of said lower tubular extension and wherein said sleeve is bonded to said lower extension with cement.

References Cited by the Examiner UNITED STATES PATENT 1,557,923 10/ 1925 Carroll. 2,410,027 11/1946 Guildford 285-339 2,464,332 3/1949 Maund et a1. 2,488,484- 11/1949 Vander Clute 16116 X 2,620,025 12/1952 Powers. 3,083,041 3/1963 Owenma-rk 285--302 X FOREIGN PATENTS 979,775 v1 2/ 1 950 Fnance.

26,754 11/1896 Great Britain. 861,531 2/1961 Great Britain. 103,389 2/1964 Norway.

CARL W. TOMLIN, Primary Examiner.

D. W. AROLA, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,284,114 November 8, 1966 Wilfred M. McCord Jr. et al.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 4, line 11, for "said cylindrical first" read said first cylindrical line 16, after "annular" strike out "tapered".

Attest:

EDWARD J. BRENNER Commissioner of Patents ERNEST W. SWIDER Attesting Officer

Claims

1. A TELESCOPING POLE FOR USE WITH A PRUNING SAW OR THE LIKE COMPRISING, IN COMBINATION, AN UPPER TUBULAR POLE EXTENSION, A LOWER TUBULAR POLE EXTENSION HAVING AN INNER DIAMETER GREATER THAN THE OUTER DIAMETER OF SAID UPPER POLE EXTENSION, SAID UPPER EXTENSION BEING TELESCOPED WITHIN SAID LOWER EXTENSION, AN EXTERNALLY THREADED MEMBER DISPOSED AT THE UPPER END OF SAID LOWER POLE EXTENSION AND FIXED RELATIVE TO THE LATTER, AN UPPER INNER PORTION OF SAID THREADED MEMBER BEING FORMED AS A FIRST ANNULAR TAPERED SURFACE EXTENDING UPWARDLY AND OUTWARDLY, A NUT MEMBER THREADED ON THE UPPER END OF SAID THREADED MEMBER, SAID NUT MEMBER BEING ROTATABLE ON SAID THREADED MEMBER FOR ADJUSTING THE RELATIVE AXIAL POSITION OF SAID NUT MEMBER AND SAID THREADED MEMBER, A SECOND ANNULAR TAPERED SURFACE FORMED INTERNALLY ON SAID NUT MEMBER PROXIMATE THE UPPER END THEREOF, SAID SECOND ANNULAR TAPERED SURFACE EXTENDING DOWNWARDLY AND OUTWARDLY AND BEING DISPOSED ABOVE SAID FIRST ANNULAR TAPERED SURFACE SO AS TO DEFINE THEREBETWEEN A CHAMBER OF VARIABLE AXIAL LENGTH DETERMINED BY THE RELATIVE AXIAL POSITION OF SAID NUT MEMBER ON THE THREADED MEMBER, AND AN ELASTIC HELICAL COLLET SHAPED APPROXIMATELY AS A SPLIT RING WITH AXIALLY SPACED ENDS WHEN IN AN UNCONFINED STATE, SAID COLLET HAVING UPPER AND LOWER ANNULAR INCLINED SURFACES FORMED ON THE OUTSIDE THEREOF FOR ENGAGEMENT WITH SAID FIRST AND SECOND ANNULAR SURFACES RESPECTIVELY OF THE NUT AND THREADED MEMBERS WHICH DEFINE A CHAMBER OF VARIABLE AXIAL LENGTH, SAID COLLER BEING POSITIONED WITHIN SAID CHAMBER SO AS TO SUBSTANTIALLY ENCIRCLE SAID UPPER POLE EXTENSION AND BEING SEATED AGAINST SAID FIRST ANNULAR TAPERED SURFACE BETWEEN THE LATTER AND SAID SECOND ANNULAR TAPERED SURFACE ON SAID NUT MEMBER, WHEREBY SAID UPPER TUBULAR EXTENSION MAY BE RELEASABLY LOCKED IN POSITION RELATIVE TO SAID LOWER TUBULAR EXTENSION BY THREADING SAID NUT DOWNWARDLY ON SAID THREADED MEMBER SO AS TO DECREASE THE AXIAL LENGTH OF SAID CHAMBER AND DEFORM THE ELASTIC COLLET FROM ITS INITIAL HELICAL TO A MORE NEARLY CIRCULAR SHAPE AND THEREBY CAUSE SAID COLLET TO BE CLAMPED BETWEEN SAID FIRST AND SECOND ANNULAR TAPERED SURFACES AND TO TIGHTLY ENGAGE SAID UPPER EXTENSION TO HOLD SAID UPPER EXTENSION AGAINST AXIAL MOVEMENT RELATIVE TO THE LOWER POLE EXTENSION.