US2835493A - Hydraulically adjustable stilts - Google Patents

Description

May 20, 1958 R. P. sKAGGs ETAL HYDRAULICALLY ADJUSTABLE STILTS Filed April 14, 1955 INVENTOR aeffj? J/fa ATTORNEY United Stats This stilts.

The invention is more particularly concerned with stilts of the general character disclosed in our Patent invention relates to hydraulically adjustable No. 2,659,087, issued November 17, 1953, and of which the present invention is an improvement characterized principally in the provision of hydraulic means for effecting vertical adjustment of the stilts.

The primary object of the present invention is to provide a stilt having a base from which an outer tube projects upwardly, a foot rest having a depending inner tube telescopically engaged within the rst tube, a third tube projecting upwardly from the foot rest, and valve controlled by-pass means for controlling the ilow of iluid from said inner and outer tubes to said upwardly projecting tube, and vice-versa, for effecting vertical adjustment ofjthe stilt,

A further object of the invention is to provide an improved base wherein same is yieldable in action.

A still further and more specific object of the invention is to provide a foot rest, a ground engageable base suspended from the foot rest by telescoping tubes, a fluid reservoir tube extending upwardly from the foot rest, and valve-controlled means in the foot rest for exchange of iluid between said reservoir tube and said telescoping tubes for relative adjustment of the foot rest and the base.

Other objects and advantages of the invention will become apparent in the coursev of the following detailed description, taken in connection with the accompanying drawing, wherein:

Figure l is an elevational view of the improved stil-t in accordance with a preferred structural embodiment thereof, the View being broken away and partly in section.

Fig. 2 is an elevational View as of Fig. l.

Fig. 3 is an enlarged fragmental vertical section as observed in the plane of line 3 3 on Fig. l.

Fig. 4 is a horizontal sectional view as observed in the plane of line lfd on Fig. l.

Fig. 5 is an enlarged vertical section of the upper end of a fluid storage tube.

Fig. 6 is a horizontal sectional the plane of line 6-6 on Fig. 3.

Referring now in detail to the drawing, 10 designates a foot rest which is in the form of a casting and which is provided with a plane foot-engaging upper face 11 and a toe-receiving arcuate member 12 which projects upwardly from such face at an edge of the casting, as shown in Fig. 4.

The casting 10 is provided with a cylindrical recess 13 opening through the lower face thereof, and a second transversely spaced parallel cylindrical recess 14 opening through the upper face thereof.

The recess 13 communicates with a fluid port 15 through an opening 16. The recess 14 communicates observed from the left view as observed in 2,835,493 Patented May 2G, 1958 With a Huid port 17 through a valve-controlled opening 18 and the two ports 15' and 17, which are in vertically spaced parallel relation, are in communication through a third uid port 19. The outer end of each of the ports 15, 17, 19 is normally closed by a plug 20.

An inner tube 21 has its upper end rigidly received Within the recess 13, andthe tube 21 is telescoped within an outer tube 22 whose lower end is secured within a recess 23 in a rocker block 2d which is pivoted, as at 25, to anges 26 projecting upwardly from a groundengageable base plate 27. A coil spring 28 is disposed at each side of pivot 25 with the opposite ends thereof engaging rocker block 24 and base plate 27 for a purpose later referred to.

A pin 29 extends through diametrically opposed apertures in the outer tube 22 and also through diametrically opposed and axially elongated slots 30 in the inner tube 21.A g

A coil spring 31 is disposed within the inner tube 21 with its upper end engaged with a shoulder 32, and the lower end of the spring engages the pin 29, the spring acting to normally raise the foot rest 10 relative to the base plate 27. A combined collar andgasket 33 surrounds the upper end of the outer tube 22 and is secured thereto by a set screw 34, whereby the structure is rendered air-tight.

In use, the inner and outer tubes 21, 22 as well as the tluid ports 15, 17 and 19 are filled with oil and an oil storage tube 35 has its lower end rigidly received within the recess 1d, and the upper end thereof is provided with a bushing 36 in which is threadedly engaged the knob 3'7 of a valve stem 3S whose lower end is provided with a valve 39 for controlling the opening 18.

From the above disclosure, it will be apparent that the'system, including the ported foot rest casting 10, telescoping tubes 21, 22 and ythe fluid reservoir tube 35, is air-tight, whereby adjusting forces will be automatically eiected by Huid-pressure and vacuum. Thus, when valve 39 is seated as indicated on the drawing, a lifting of the foot rest will result in a vacuum in the tubel assembly 21, 22, which will cause a lifting of the base plate 27, as is necessary in a walking operation by a person using a pair of the stilts. v

If the valve 39 be opened and the foot rest 10 be raised, the spring 31 will cause separation of the foot rest 10 and base plate 2'7 through telescopic movement of the tubes 21 and 22, with a resulting flow of fluid from the tube 35 into the tubes 21, 22.

Upon closure of the valve 39, a` vacuum condition exists in the lower telescoping tubes 21, 22. A reverse operation will take place upon opening the valve 39 and putting pressure on the foot rest 10, under which condition iluid will flow back into the fluid reservoir tube 35 with a resulting lowering of the foot rest.

From the above, it will be apparent that the structure as disclosed provides for quick and easy adjustment of thestilt. The slots 39 in the inner tube 21 may be of any desired length. They will, however, be relatively short, as indicated, since the necessary range of adjustment is relatively small under ordinary circumstances.

The springs 28 provide a restraining action in the ankles of persons using the stilt, while the pivotal connection 25 provides for proper contact of the base plates 27 with the ground.

It is to be further observed that the fluid reservoir tube 35 provides a hand-grip for a user of the stilt.

While we have disclosed the invention in accordance with a single specic structural embodiment thereof, such is to be considered as illustrative and not restrictive, the scope of the invention being defined in the sub-joined claims.

fluid-tight seal therebetween, ground-engaging means 01'1` the lower end of the outer tube, a coil spring supported within said tubes with the opposite ends thereof reacting on said foot rest and said outer tube, a fiuid reservoir tube projecting upwardly from said foot rest and having its lower end supported therein, ports in said foot rest providing communication between said tclescoping tubes and said duid reservoir tube, valve means in said foot rest controlling said ports, and manually operable means supported by said lluid reservoir tube for operating said valve means.

2. The structure according to claim l, wherein said manually operable valve-operating means comprises a knob accessible from the upper end of said fluid reservoir tube and having a threaded engagement therewith, and a valve stem depending from said knob, extending through said uid reservoir tube and connected to said valve means within said foot rest.

3. The structure according to claim l, wherein said telescoping tubes and said fluid reservoir tube have their axes in a plane intersecting said foot rest intermediate the ends thereof, and an arcuate toe-receiving member disposed at one end ofthe foot rest.

4. The structure according to claim 3, wherein said telescoping tubes have their axes in a plane bisecting said toe-receiving member, and said tluid reservoir tube being disposed' laterally of said plane.

5. The structure according to claim l, wherein said ground-engaging means comprises a rocker block rigidly supported by the lower end of said outer tube, a base plate pivotally connected to said rocker block, and spring means interposed between said rocker block and said base plate, said spring means providing a restraining action in the ankles of a user, and the pivotal connection between said rocker and said base plate providing proper contact of the latter with the ground.

6. The structure according to claim 5, wherein said 4 base piate is flat and is provided with upwardly projecting laterally spaced flanges between which said rocker block is disposed, and a pin extending through said flanges and said rocker block providing said pivotal connection.

7. The structure according to claim l, wherein said foot rest comprises a casting having a plane Lipper face, a cylindrical recess opening through each of the lower and upper faces of said casting with their axes in spaced parallel relation and in which recesses the upper end of said inner tube and the lower end of said uid reservoir tube respectively are rigidly secured, said ports comprising a horizontal one opposite the closed end of each recess, and a third one normal to said first two ports and in communication therewith, openings between the recesses and said iirst two ports, and said valve means comprising a plunger' type valve cooperating with one of said openings.

8. A hydraulically adjustable stilt, comprising a foot rest provided with a downwardly opening cylindrical recess, a pair of telescopical tubes depending from the foot rest with the upper end of the inner tube supported in said recess and engaging the bottom thereof, groundengaging means on the lower end of the outer tube, said inner tube having laterally opposed elongated slots therein intermediate its ends, said outer tube being provided with a diametrical pin movably disposed within said slots, a coil spring disposed within said inner tube with its upper and lower ends bearing on said recess bottom and said pin respectively for normally separating said tubes, a iiuid reservoir tube projecting upwardly from said foot rest and having its lower end supported therein, ports in said foot rest providing communication between said telcscoping tubes and said uid reservoir tube, valve means in said foot rest controlling said ports, and manually operable means supported by said iiuid reservoir tube for operating said valve means.

References Cited in the tile of this patent UNITED STATES PATENTS 238,042 Herrington Feb. 22, 1881 2,351,145 Pearson June 13, 1944

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