US1896086A - Tripod - Google Patents

Description

Fgb. 7, 1933. A. s. HOWELL 1,396,086

TRIPOD Filed Oct. 21, 1929 2 Sheets-Sheet l Feb. 7, 1933.v 1 HOWELL 1,896,086

TRIPOD Filed' Oct. 21, 1929 2 Sheets-Sheet 2 I/I/I/IIIIIII "/1, I'll/II. 1",,

Patented Feb. 7, 1933 2 UNITED STATES PATENT OFFICE ALBERT S. HOWELL, OF CHICAGO, ILLINOIS, ASSIGNOR. TO THE BELL & HOWELL COMPANY, OF CHICAGO, ILLINOIS, A COBYORA'IION OF ILLINOIS TRIPOD Application filed October 21, 1929. Serial No. 401,082.

My invention relates particularly to tripods forphotographic cameras, although not limited to this use alone.

The lprinci l abject .of my invention region Of a novel and depend ig u inweight and sides'intheprow toward the PIfOd'llClilOlI o a limetalltripod.

' With this object in View myinventionconsists in certain features'of novelty in the construction, combination and arrangement of parts by which the said object and certain other objects hereinafter appearing, are effected, all as fully described with reference to the accompanying drawings and more particularly pointed out in the appended claims.

In the said drawings Figure 1 is a perspective view of a tripod embodying my invention and set up ready for use;

Figure 2 is a side elevation of the tripod when folded;

Figure 3 is a condensed longitudinal section of a portion of one of the legs of the tripod;

Figure 4 is a bottom view of the head structure of the tripod;

Figure 5 is an axial sectional view of the aforesaid head structure; and

Figure 6 is a section on the line 6-6 of Figure 3.

Like characters of reference indicate like parts in the several views.

Referring to the drawings, the tripod conunderstood that the description applies to all.

and the same reference characters on the drawings indicating like parts thereof.

Referring particularly to Figure 3. a leg involves an upper tube 'l and a smaller lower tube 2 telescopically engaged within the upper tube for sliding movement, the upper end of the lower tube being expanded, as

'ewiparticularly I r mal portion and the contracted lower end 4 sists generally, as is usual, of a head struc designated at 3, to have a sliding fit with the main portion of the upper tube, and the lower end of the upper tube being contracted, as designated at 4 to have a sliding fit with the -main portion of the lower tube below the ex- 5 panded portion 3 thereof.

The portion of the tube 1 betweenthe northereofis in the form of a taper portion 10, while the portion of the tube 2 between the normal portion and the expanded upper end 3 thereof is in' the form of a taper portion 20 engageable within the taper portion 10 when the tubes are extended, to provide a shoulder stop limiting extending movement of the 6 tubes, which engagement, by reason of the taper shoulder engagement, prevents relative lateral movement of the tubes at this point, as shown in Figure 3, the construction providing a bearing engagement, between 7 the tubes, of constant length and giving the leg structure a tapering appearance when ,extended.

The upper and lower tubes 1 and 2 are adjustably fixed with one another for adjusting the length of the leg in the followmg manner.

The upper end portion of the inner tube 2 engaged within the tube 1 is longitudinally slit by diametrical slots 5, and a tapered ex- 50 pansion cup 6 is disposed within the enclosure of the tubes and is engageable downwardly upon the slit upper end of the inner tube to expand the slit upper end portion thereof against the outer tube 1 to fix the tubes in adjusted positions throughout their relative movement.

Upward movement of the cup 6 with reference to the tube 2 releases the tubes for relative movement, and movement of the cup 6 99 with reference to the tube 2 is conveniently effected in the following manner.

A rod 7 extends within the tube 2 and, having its upper end engaged in a central aperture through the expansion cup 6, is secured therewith-longitudinally by means of a head 8 on the rod above the cup 6 and a pair of radial projections 9 swaged on the rod below the cup 6. The rod 7 extend s downwardly from the mo cup 6 to and below the lower end of the tube 2, and extends for sliding movement through a central aperture in a circumferentially flanged thimble 11 press fitted into the lower reduced end of the tube 2, the rod 7 being prevented from rotation with reference to the thimble and tube 2 by means of keys 12 swaged on the rod and slidably engaging keyways 13 in the thimble. See Figures 3 and 6.

A helical spring 14 encircles the rod 7 ust above-the thimble and reacting thereon operates the rod 7 and with it the cup 6 up wardly by means of a washer 15, also encircling the rod above the spring and engaged thereby, and radial projections 16 swaged on the rod above the washer and engaged thereby.

As actuated upwardly by the spring 14 the cup 6 is moved out of expanding relation with the slit upper end of the tube 2, so that the tubes 1 and 2 may be moved longitudinally with reference to each other for extending or shortening the leg.

Downward or expanding movement of the rod 7 and cup 6 is effected manually in the following manner.

The rod 7 extends below or outwardly of the lower end of the tube 2 with a screwthis portion 17 is a tip member 18 which is pointed at its lower end for non-slipping engagement on the surface upon which the tripod rests when set up.

ress fitted upon a reduced and shouldered upper portion of the tip member 18, by means of an axial bore therethrough, is a cup shaped manipulating member 19 the flange of which extends upwardly about the lower end of the tube 2.

The manipulating member 19 bears upwardly against the thimble 11, and rotation of the manipulating member in one direction acts upon the rod 7 to pull it, and with it the expansion cup 6, downwardly, whereby to expand the slit upper end of the tube 2 against the tube 1 to fixthe tubes in the desired relative position.

Rotation of the member 19 in the opposite direction permits the spring 14 to actuate the rod 7, and with it the cup 6, up'wardly,

I whereby to move the cup 6 out of expanding relation with the slit upper end of the tube 2 to permit relative movement of the tubes land 2.

Springs 21 of U-shape are disposed adjacent the upper end of the tube 2, and being disposed diametrically thereof engage in diametrically opposite slots 5 and against the outer tube 1 to provide a constant initial 7 friction on the tube 1 to prevent rotation of the tube 2 during manipulation of the member 19, these springs being confined longitudlnally with the tube 2 by reason of the fact that they are engageable with the bottoms of the slots 5 and with the cup 6 which moves with the tube 2 relative to the tube 1.

A collar 22 is secured on the rod 7 immediately below the keys 12 of the rod and is adapted to abut the thimble 11 to prevent derangement of the rod 7 in the event that the members 19 and 18 are unscrewed too far or removed from the rod.

It will be observed, thatthe leg is readily adjustable, the securing mechanism, with the exception of the manipulating member 19, being enclosed within the tube structure with obvious advantages; that the structure affords rigidity and simplicity in appearance and permits the holding of the legs in compact adjacent parallelism, as shown in Figure 2; and that there are no inconvenient lateral projections on the leg structure.

It will be observed that when a leg is extended and the upper end of the inner tube 2 expanded against the upper tube 1, as shown in Figure 3, the taper shoulder engagement, afforded by the taper portions 10 and 20 of the tubes, is free of lost motion while the tubes are at the same time clam ed together above the taper engagement, t us providing a rigid joint.

A cup shaped cap member'23 is screwthreaded by means of the lip portion thereof on the upper end of the upper tube 1 of the leg, and is provided with a diametrical slot 24 through the closed end portion thereof. See particularly Figures 4 and 5.

A pivot member 25, preferably formed of a plate of sheet metal, has a flat portlon thereof engaged in said slot. Shoulders 26 are formed on the flat portion of the pivot member and engage the cap member at the ends of the slot 24 for preventing lateral movement of the pivot member in the slot,

and lugs 27, formed on said portion of the pivot member intermediate said shoulders and disposed interiorly of the cap member, are oppositely bent against the cap member for securing the pivot member, engaged in the slot, with the cap member.

Thus the pivot member is adequately secured with the upper tube 1 of the leg, the cap member providing a suitable termination of the upper end of this tube.

The pivot member 25 is blfurcated above the cap member 23 and the spaced portlons thereof are circularly bent, as designated at 28, to form alined holes, and a pin 29 extends across between said spaced portions and is engaged in said holes for purposes heremafter described.

The head of the tri od is designated generally at 31 and is pre erably formed of sheet metal. See Figures 1, 2, 3 and 4.

It consists of a central circular portion 32, a downwardly offset portion 33 surrounding the central portion, and a downwardly projecting marginal flange 34 which has three straight portions 35 disposed in equally spaced angular relation. See Figures 4: and 5.

A. spring member 36, formed of flat stock, is provided with three radial arms 37 equally spaced angularly thereabout. This spring member is secured, centrally thereof and of the head 31, upwardly against the central portion 32 of the head in the following manner.

A stud 38, provided with an intermediate enlargement 39, has one portion thereof assed downwardly through axial apertures 1n the central portions 32 of the head and of the spring member 36, and a nut 41 is screwthreaded on the lower end of the stud and clamps the head, the spring, and a washer 42 between it and the intermediate enlargement 39 of the stud. See Figure 5.

The arms 37 of the spring member 36 are disposed correspondingly with the straight portions of the flange 34 of the head, and are formed so that they radially engage the pins 29 upwardly, between the spaced portions of the bifurcated pivot members 25, for maintaining the circularly bent portions 28 of the pivot members upwardly against the lower surface of the offset portion 33 of the head and against the straight portions 35 of the flange 3 to form pivotal connections between the head and the legs of the tripod.

Thus are provided simple and efiective ivotal connections between the head and the egs of the tripod, which provides a desirable friction, these joints providing-for the folding of the tripod and the spreading of the legs as desired. See Figures 1 and 2.

The stud 38 extends upwardly from the enlargement 39 thereof and from the head 31, and this portion of the stud is screwthreaded, as designated at 43, for the mounting of a device, such as a photographic camera, uponthe head of the tripod.

While I have described and shown the preferred embodiment of my invention I do not wish to be limited to the precise details of construction as changes may readilybe made without departing from the spirit of my invention, but having thus described my invention, I claim as new and desire to secure by Letters Patent the following:

1. In a tripod leg the combinationwith a pair of tubes telescopically engaged for slidmg movement and the inner of which has a longitudinally slit end portion engaged in the outer tube, of an expansion mem r within the enclosure of said tubes at said slit end portion and movable longitudinally of said inner tube for expanding said slit end portion against the outer tube and releasing the same, an exposed manually operable member at the other end of said inner tube and rotatable with respect thereto, a rod extending within said inner tube and connected with said expansion member for operating the same in its said movement, a helical spring encircling said rod for operating the same in a direction inwardly from said other end of said inner tube, and a screw connection between said manually operable member and sald rod whereby. said expansion member is gontrolled by said manually operable mem- 2. In a tripod leg the combination with a pair of tubes telescopically engaged for sliding movement and the inner of which has an expansible portion engaged in the outer tube, of an expansion member within the enclosure of said tubes and movable longitudinally of said inner tube for expanding said expansible portion thereof against the outer tube and releasing the same, a rod extending within said inner tube and connected with said expansion member for operating the same, a bearing at the outer end of said inner tube and havin engagement with said rod for longitudina movement of the rod and to prevent rotation thereof with reference to said inner tube, a helical spring encircling said rod inwardly of said bearing for operating the rod in a direction inwardly from the outer end of said inner tube, and a manually operable member having a screwthreaded engagement with the outer end of said rod for operating the rod against the influence of said spring.

In witness whereof I hereunto ailix my signature this 10th da of October, 1929.

AL ERT S. HOWELL.

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