Stilt device

Abstract

A stilt device for extending a person's effective leg length and simulating one's natural ankle movement while walking and comprising a movable rectangular frame structure and leg attach means secured thereto, said frame structure comprising a load bearing telescopic strut and partial load bearing telescopic strut or control lever, an elongated horizontally disposed foot member pivotally secured to the lower ends of the strut members to allow pivoting thereof within the plane of the frame structure, an elongated horizontally disposed shoe plate pivotally secured to the upper ends of the strut members to allow pivoting thereof within the plane of the frame structure, vertically disposed yieldable means secured to one strut member, horizontally extending actuator arm rigidly secured to the opposite strut member and operably connected to the said yieldable means for cushioning and restricting the pivotal motion of the frame structure. The leg attachment means is adjustable in height, laterally and rotationally with respect to the frame structure.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to improvements in leg extension mechanisms but more particularly, but not by way of limitation, to a walking stilt device particularly designed and constructed for elevating workmen such as ceiling painters, installers and the like, the said stilt being constructed to supplement or facilitate natural leg and ankle movement when a user is walking thereon.

2. Description of the Prior Art

Heretofore, workers involved in overhead construction, ceiling panel installation and the like have primarily utilized elevatable platforms, scaffolding or other temporary structures in accomplishing their job duties. These devices have proven to be inefficient since they must be often moved to new positions and are dangerous in that they for the most part are inherently instable.

A walking stilt was developed in the U.S. Pat. No. 3,102,272 issued in 1963 and entitled "STILT" which teaches the use of a leg extension device having a basic rear support strut pivotally secured between an upper shoe plate and a lower base plate. This stilt provides toe support and restricted pivotal action by way of a V-shaped control lever working in conjunction with a spring mechanism located on the rearward strut. The present invention embodies several improvements over Emmert U.S. Pat. No. 3,102,272 in comfort, scope and usage and manufacturability. Further, the Emmert stilt U.S. Pat. No. (3,102,272) is not adjustable in height nor capable of being so adjustable in its disclosed configuration. Many times for comfort of the workmen and in order that the device may be used for more applications it is necessary or desirable to adjust the height of the stilt in relation to the work and often it is desirable to provide a single pair of stilts for use by several different workmen who may be of different heights.

SUMMARY OF THE INVENTION

The present invention includes the objects as specified in the aforesaid issued patent to Emmert and is constructed for improving and overcoming any disadvantages in the prior art. The present stilt device provides a spaced pair of parallel substantially vertical struts which are pivotally connected to the top to a shoe attachment plate and pivotally connected to a foot plate at the bottom thereof to form a movable parallelogram frame structure. This substantially parallelogram shape will be retained regardless of the pivotal position of the frame structure. Cushioning or restricted movement of the frame structure is provided by yieldable means which is secured to one of the struts and an actuator arm secured to the other strut and being operably connected to the yieldable means. Stiffness of the stilt structure may be controlled by adjustment of the yieldable means or replacement thereof by a stronger spring or the like.

By maintaining the struts in a parallel relationship, toe pressure is transmitted directly down the forward strut to the foot or base plate and heel pressure is transmitted directly down the rear strut to the base plate thereby avoiding the application of direct side loads from one strut to the other.

The substantially rectangular structure further allows the struts to be of a telescoping design for height adjustment to fit the particular job at hand or to be usable by different sized workmen. This parallel construction also allows the vertical struts to be constructed to be interchangeable for reduction of manufacturers cost.

From a manufacturing standpoint, the strut components are of the same basic construction so that they may be made into either front struts or rear struts with only assembly variations.

The leg attachment device in the present invention is also designed to be adjustable in height, laterally and rotatably to fit substantially any sized user.

Replaceable and interchangeable base plate pads manufactured from a resilient material are provided for greater traction, protection of the floor surface and shock absorption which will greatly enhance the safety of the stilt device. Sliding friction is greatly reduced between the telescoping parts by the use of a novel pair of plastic inserts secured to the strut members.

DESCRIPTION OF THE DRAWINGS

Other and further advantageous features of the present invention will hereinafter more fully appear in connection with a detailed description of the drawings in which:

FIG. 1 is a side elevational view of a leg extension strut device embodying the present invention.

FIG. 2 is a back elevational view of the strut of FIG. 1.

FIG. 3 is an elevational exploded detail view of the base plate and removable foot pads of the stilt.

FIG. 4 is a plan view of the base plate of FIG. 3.

FIG. 5 is a sectional end view of a strut taken at the upper end of the inner telescoping member.

FIG. 6 is an elevational sectional view of the strut taken along the broken line 6--6 of FIG. 5.

FIG. 7 is a sectional end view of a strut taken at the lower end of the outer telescoping member.

FIG. 8 is an elevational sectional view of the strut taken along the broken line 8--8 of FIG. 7.

FIG. 9 is a sectional elevational view of the yieldable means and actuator of FIG. 1.

FIG. 10 is a perspective view of the adjustment bracket for the leg attach means of FIGS. 1 and 2.

DETAILED DESCRIPTION

Referring to the drawings in detail, reference character 10 generally indicates a stilt device comprising a parallelogram shaped frame structure 12 and a leg attachment means 14 secured thereto.

The movable rectangular shaped frame structure 12 comprises an elongated substantially vertically disposed front strut generally indicated by reference character 16, a substantially identical rear strut 18 which is disposed parallel to the strut 16 and spaced rearwardly therefrom. The frame structure 12 also comprises an elongated horizontally disposed shoe plate 20 which is pivotally secured to the upper ends of the struts 16 and 18 by means of the pivot pins 22 and 24 respectively. An elongated base plate 26 is longitudinally disposed and pivotally secured to the lower ends of the struts 16 and 18 by means of the pivot pins 28 and 30 whereby since the struts 16 and 18 are parallel and the shoe plate 20 is parallel with the base plate 26, the frame structure 12 will maintain a parallelogram shape regardless of the pivoting actions of the shoe plate 20 and base plate 26 with respect to the struts 16 and 18.

The front strut 16 comprises an outer elongated sleeve member 32, the upper end thereof being provided with a bracket member 34 rigidly secured thereto. The bracket member 34 is pivotally secured to the shoe plate 20 by means of the pivot pin 22. The lower end of the sleeve member 32 is provided with a sleeve insert 36 which will be hereinafter described. The front strut 16 also comprises an elongated tube member 38 which is reciprocally disposed within the sleeve member 32, the lower end thereof extending downwardly from the said sleeve member 32. The lower end of the tube member 38 is expanded outwardly at 40 to approximately the same shape and size as that of the sleeve member 32 and is provided with the bracket 42 rigidly secured thereto. The bracket 42 is substantially identical to a mirror image of the bracket 34 and is pivotally secured to the forward portion of the base plate 26 by means of the pivot pin 28. The upper end of the tube member 38 is provided with a sleeve insert 44 as depicted in FIGS. 5 and 6 which is slidably disposed within the sleeve member 32 whereby the sleeve insert 44 carried by the tube member and the sleeve insert 36 carried by the sleeve member serve to separate the sleeve member 32 from the tube member 38 for ease of sliding one with respect to the other.

The lower end of the sleeve member 32 is provided with a pair of oppositely disposed, longitudinal inserts 46 and 48, the insert 46 being located in front of the sleeve member 32 while the insert 48 is located in the rear and aligned therewith, the insert 48 being internally threaded. A locking bolt 50, having a wing type handle 52 secured to one end thereof and being threaded at the other end is journaled through the inserts 46 and 48 in alignment with a plurality of vertically spaced holes 55 provided in the tube member 38. Therefore, to adjust the length or height of the strut 16 the locking bolt 50 is removed and the tube member 38 is adjusted within the sleeve member 32 to the approximate desired height and wherein the inserts 46 and 48 of the sleeve member 32 are in alignment with the bores 55 of the tube member 38, the bolt 50 is then inserted through the inserts 46 and 48 and the aligned holes 55 for securing the said tube member 38 at a particular location within the sleeve member 32.

The rear strut 18 is constructed to be substantially identical to the strut 16 and comprises an outer sleeve member 54 which is pivotally secured to the rear portion of the shoe bracket 20 by means of a bracket 56 and a pivot pin 24. The rear strut 18 also comprises a tubular member 58 which is slidably disposed in the lower end of the sleeve member 54 and is provided with an enlarged base portion 60 which is pivotally secured to the rear portion of the base plate 26 by means of a bracket 62 and the pivot pin 30. The bracket 62 is substantially identical to the mirror image of the bracket 56. The rear strut 18 is likewise adjustable in height by means of a plurality of bores 55 within the tube member which aligns with a locking bolt 64 to be substantially identical in construction and operation as that of the locking bolt 50 of the forward strut 16.

A yieldable means generally indicated by reference character 19 is interposed between the vertical strut members 16 and 18 and operably connected therebetween to cushion and restrict the pivotal action of the parallelogram framed structure 12.

Referring now to FIG. 9, the yieldable means 19 comprises a pair of vertically spaced substantially identical spring nesting bracket members 66 and 68 which are secured to the sleeve member 54 and extends forwardly therefrom. An elongated bolt 70 having threads 72 at the upper end thereof and threads 74 at the lower end thereof is secured at the upper end thereof to the bracket 66 by a pair of oppositely disposed nuts 76. The bolt 70 is secured at the lower end thereof to the bracket 68 by a pair of oppositely disposed nuts 78. An upper spring adjuster plate 80 is threadably secured to the bolt 70 directly below the bracket 66 and a substantially identical oppositely disposed spring adjuster plate 82 is threadably disposed on the bolt 70 directly above the lower bracket 68. A plastic spring retainer guide 84 is slidably disposed on the bolt 70 adjacent to and directly below the spring adjuster plate 80 and a substantially identical plastic spring retainer guide 86 is slidably disposed on the bolt 70 adjacent to and directly above the adjuster plate 82.

An elongated actuator arm 88 is secured at one end thereof to the sleeve member 32 and extends rearwardly therefrom. The rearwardly extending end portion of the bracket 88 is provided with a horizontally disposed slot 90 for slidably receiving the bolt 70 therein. A spring retainer guide 92 which is substantially identical to the spring retainer guides 84 and 86 is slidably disposed on the bolt 70 adjacent to and directly above the slot 90 of the actuator arm 88. A substantially identical spring retainer guide 94 is slidably disposed on the rod 70 and is located adjacent to and directly below the slot 90 of the actuator arm 88. An upper helical compression spring 96 is longitudinally disposed around the rod 70 between the spring retainers 84 and 92 and a lower compression spring 98 is disposed around the rod 70 between the spring retainers 86 and 94.

Therefore, when the shoe bracket 20 is moved forwardly thereby pivoting the upper ends of the struts 16 and 18 in a forward direction as shown by the dashed lines of FIG. 1, the actuator arm 88 moves upwardly with respect to the spring rod 70 thereby compressing the compression spring 96 which tends to cushion and restrict the forward movement of the shoe plate 20. Likewise, when the shoe plate 20 is moved rearwardly thereby pivoting the struts 16 and 18 in a rearward direction as also shown in FIG. 1 the actuator arm 88 moves downwardly with respect to the spring rod 70 thereby compressing the compression spring 98 which in turn cushions and restricts movement in a rearward direction.

It has been found that better results are obtained when the upper spring 96 is constructed from a stiffer material than that of the lower spring 98.

Referring now to FIG. 5 reference character 32 generally indicates the outer sleeve member of the front strut 16. The sleeve member 32 is made up of two substantially U-shaped channel members 100 and 102. The sidewalls of the channel 102 are formed inwardly, the outer edge thereof being secured to the channel member 100 between the side plates of the channel 100, thereby forming attachment slots 104 and 106 on either side thereof. FIG. 5 shows a typical attachment of the actuator arm 88 within the attachment slots 104 and 106 by means of rivet members 108 and 110 respectively. The actuator arm 88 is also attached to the channel member 102 by means of rivets 112 and 114. The upper end of the tube member 38 is slidably disposed within the outer sleeve 32 and is spaced therefrom by means of the upper sleeve insert 44. The sleeve insert 44 comprises a pair of concentrically disposed plastic sleeves 116 and 118, the inner sleeve 116 being provided with a pair of rectangular holes 120 and 122 therein for receiving an inwardly extending pair of attachment nubs 124 and 126 which are provided at the upper inside wall of the tube member 38. The upper sleeve insert 44 may then be slid onto the upper end of the tube member 38 and locked in place by means of the inwardly extending nubs 124 and 126 being popped into the rectangular apertures 120 and 122, respectively. The inside sleeve 116 of the insert 44 is provided with a strengthening member 128 thereacross. It is readily apparent that the outer sleeve member 32 and the tube member 38 may be constructed of material having substantially any cross-sectional shape such as a circular cross-sectional shape but the shape hereinbefore described has been found at this point to be economically feasible while providing sufficient strength for the strut.

Referring now to FIGS. 7 and 8 reference character 32 again generally indicates the outer sleeve member of the forward strut 16 and reference character 38 indicates the slidably disposed inner tube member. The inner tube member 38 is also provided with a pair of oppositely disposed vertical stiffeners 39 along the spaced adjustment holes 55 to provide added load carrying capabilities. The stiffeners 39 may be constructed as an integral part of the tube member 38. The lower sleeve insert 36 is disposed between the sleeve member 32 and the tube member 38 and is provided with oppositely disposed outwardly extending nubs 130 and 132 which extend outwardly into a pair of oppositely disposed rectangular apertures 134 and 136, respectively, adjacent to the lower end of the sleeve member 32. The lower end of the sleeve member 36 is provided with an outwardly extending flange portion 138 around the outer periphery thereof to prevent the sleeve member from slipping upwardly between the tube member 38 and the outer sleeve member 32. Once the nub members 130 and 132 of the sleeve member 36 are snapped into place within the apertures 134 and 136, respectively, the sleeve member 36 is prevented from sliding downwardly out of the outer sleeve member 32 and is likewise prevented from sliding upwardly between the outer sleeve 32 and the tube member 38.

It is readily apparent that the sleeve inserts 36 and 44 serve to keep the tube member 38 slidably disposed within the outer sleeve 32 and sufficiently spaced therefrom to prevent any metal to metal contact or wear therebetween. The rear strut 18 is likewise provided with upper and lower sleeve inserts substantially identical to those hereinbefore described for the strut member 16 and it is likewise apparent that in the construction and manufacture of the struts 16 and 18, the said strut members may be manufactured substantially identical with each other which greatly reduces cost of manufacturing thereof.

It is again pointed out that the strut members may be of substantially any cross sectional shape and that this invention is in no way limited to the substantially rectangular strut shape disclosed herein.

Referring now to FIGS. 2 and 10, the leg attach means 14 generally comprises an outer elongated sleeve member 140 which is adjustably secured to the bracket 56 of the rear strut 18 by means of the pin member 24 extending therethrough. The bracket 144 is provided with a transversely disposed slot aperture 146 and a pair of gripping plates 148 and 147 which may be tightened against the sleeve member 140 by means of the bolts 150 and nuts 151. These gripping plates 148 are adjustably secured to the bracket by means of a vertically disposed bolt 152 which when loosened may be slid within the slot member 146 thereby allowing the sleeve member 140 to be moved inwardly adjacent to the shoe plate 20 or outwardly away from the shoe plate 20. Height adjustment of the sleeve member 140 is accomplished by loosening the nuts 151 and sliding the sleeve member 140 between the grip plates 148. An inner tube member 154 is secured at the lower end thereof to the lower end of the outer sleeve member 54 by means of a spacer 156 and bolt 158, the upper end of the tube member 154 being reciprocably disposed within the outer sleeve member 140. The upper end of the outer sleeve member 140 is provided with a semicircular shaped leg attachment pad 160 and a strap member 162 attached therein for strapping the leg attachment means 14 to the user's leg.

It is readily apparent that when the height of the stilt is adjusted, the leg attachment means 14 will move with the outer strut sleeve 54 and hence may require no additional adjustment.

The shoe plate or bracket 20 comprises a flat longitudinally disposed plate member 164 having an upwardly extending heel plate 166 attached to the rear end thereof, the said plate 164 being provided with a pair of longitudinally spaced strap members 168 and 170 for strapping the said shoe plate 164 to the user's shoes.

Referring now to FIGS. 3 and 4, the base plate 26 is provided with a pair of oppositely disposed substantially identical base pads 172 and 174. Each said pad is provided with a bottom ridged surface 176 for contacting and gripping the floor being walked upon and an upwardly extending ridge portion 178 around the outer periphery thereof. A slot or groove 180 is provided around the inner portion of the upwardly extending ridge 178 for receiving the outer periphery of the lip of the base plate 26 therein. The pad 172 is then locked into place on the base plate 26 by means of a pair of upwardly extending screws 182 and 184 which are readily secured within threaded bores 186 and 188, respectively, in the base plate 26. The base plate pad 174 is substantially identical to the base plate pad 172 and is attached to the rear end of the base plate 26 in a similar manner.

From the foregoing it is readily apparent that the present invention provides a stilt device which is completely adjustable for use with any job size and also adjustable to fit any user thereof. The novel stilt device is further provided with a unique adjustable yieldable means for cushioning and limiting the pivotal action of the parallelogram frame structure 12 thereof for substantially duplicating ordinary leg and ankle movement of the user thereof.

Whereas, the present invention has been described in particular relation to the drawings attached hereto it is readily apparent that other and further modifications apart from those shown or suggested herein may be made within the spirit and scope of this invention.

Claims

What is claimed:

1. A stilt device for extending a person's effective leg length and comprising a movable parallelogram frame structure and leg attachment means secured thereto, said frame structure comprising a spaced pair of substantially vertically disposed telescoping strut members, an elongated horizontally disposed foot member pivotally secured to the lower ends of the strut members to allow pivoting thereof within the plane of the frame structure, an elongated horizontally disposed shoe bracket pivotally secured to the upper ends of the strut members to allow pivoting thereof within the plane of the frame structure, vertically disposed yieldable means secured to one strut member, substantially horizontally extending actuator arm rigidly secured to the opposite strut member and operably connected to the said yieldable means for cushioning and restricting the pivotal motion of said frame structure.

2. A stilt device as set forth in claim 1 wherein the shoe bracket comprises an elongated horizontally disposed flat plate member having a heel stop and an ankle strap at one end thereof and a toe strap at the other end thereof and wherein the leg attachment means comprises an elongated telescoping tube being secured at the lower end thereof to one of the struts of the frame structure intermediate the foot member and the shoe bracket and capable of being moved with the shoe bracket when the struts are extended or retracted, the upper end thereof being provided with a leg pad and strap and lateral adjustment means provided on the frame structure adjacent to the heel stop of the shoe bracket and operably connected to the leg adjustment means for providing lateral adjustment of the leg attach means in a direction perpendicular to the plane of the parallelogram frame structure.

3. A stilt device as set forth in claim 1 wherein a pair of substantially identical oppositely disposed resilient foot member pads are slidably emplaced from either end of the foot member and secured by means of a transversely extending secondary fastener.

4. A stilt device as set forth in claim 1 wherein each strut member comprises an elongated outer sleeve member pivotally secured at the upper end thereof to the shoe bracket, the lower end thereof being provided with a sleeve insert, locking means provided for securing the said sleeve insert to the lower end of the sleeve member, an elongated inner tube member slidably disposed within the outer sleeve member and in sliding contact with the sleeve insert, the lower end of said inner tube member expanded to approximately the same size as outer sleeve secured to the foot member and the upper end thereof being provided with a spacer sleeve insert in sliding contact with the outer sleeve, spacer sleeve locking means for locking the said spacer sleeve insert to the upper end of the inner tube member, and adjustable fastening bolt means provided in the outer sleeve member and the inner tube member for locking the said inner tube member at a desired location within the outer sleeve member and wherein the lower end of the leg attach means is secured to the lower end of the outer sleeve member of one of the strut members.

5. A stilt device as set forth in claim 4 wherein the lower ends of each inner tube member is expanded in size and shape to be equivalent to the cross sectional size and shape of the outer sleeve member and wherein substantially identical interchangeable pivot brackets are secured to each end of each strut member.

6. A stilt device as set forth in claim 4 wherein each inner tube member is provided with a plurality of vertically spaced bores for receiving the fastening bolt means therethrough and stiffening means provided on said inner tube members along said spaced bores to provide greater load carrying capabilities, and wherein each outer sleeve member is provided with a pair of aligned inserts for threadedly receiving the fastening bolts means therethrough.

7. A stilt device as set forth in claim 4 wherein the sleeve insert comprises a plastic sleeve liner inserted within the lower end of the outer sleeve member and having an outwardly extending flange portion at one end thereof which contacts the lower end of the outer sleeve member and wherein the locking means provided for locking the said sleeve insert into the lower end of the sleeve member comprises at least one outwardly extending nub on the outer surface of the plastic sleeve liner and a corresponding aligned aperture provided in the outer sleeve member for receiving the nub therein.

8. A stilt device as set forth in claim 4 wherein the spacer sleeve insert comprises a pair of concentrically disposed spaced plastic sleeves, the outer plastic sleeve being disposed around the outer surface of the upper end of the inner tube member and the inner plastic sleeve being inserted within the inner tube member, and annular flange member joining one end of the plastic sleeves together and disposed against the upper end of the inner tube member wherein the spacer sleeve locking means for securing the said spacer sleeve insert to the upper end of the inner tube member comprises at least one inwardly extending nub adjacent to the upper edge thereof provided on the inside surface of the inner tube member and a corresponding aperture provided in the inner plastic sleeve for receiving the said nub therein.

9. A stilt device as set forth in claim 4 wherein the yieldable means comprises a spring nesting bracket rigidly secured to the outer sleeve member of one of the strut members, said spring bracket having a pair of inwardly extending vertically spaced attachment plates, an elongated vertically disposed spring rod secured between said attachment plates, an upper spring adjusting plate threadedly secured to the upper end of the spring rod directly below the upper attachment plate and a substantially identical lower spring adjusting plate threadedly secured to the lower end of the rod directly above the lower attachment plate, an upper compression spring disposed around the spring rod, the upper end thereof contactable by the upper spring adjusting plate and a lower compression spring disposed around the spring rod directly above and contactable with the lower spring adjusting plate and wherein the horizontally extending actuator arm is rigidly secured to the outer sleeve member of the opposite strut member, the inner end of the said actuator arm being slidably disposed on the spring rod between the upper compression spring and the lower compression spring whereby when the frame structure is pivoted in one direction, the said actuator arm causes compression of the first spring and when the said frame structure is pivoted in the opposite direction said actuator arm compresses the second spring.

10. A stilt device as set forth in claim 9 wherein the upper compression spring is constructed to be stiffer than the lower compression spring.

11. A stilt device as set forth in claim 9 wherein a pair of substantially identical plastic spring guides are disposed around the spring rod and retained in each end of each compression spring.

12. A stilt device for extending a person's effective leg length and comprising:

a. a first telescoping strut comprising a sleeve member and a cooperating tube member having one end thereof reciprocally disposed within one end of the sleeve member;

b. a second telescoping strut comprising a sleeve member and a cooperating tube member having one end thereof reciprocally disposed in one end of said sleeve member, the second strut being disposed parallel to and spaced from said first strut;

c. an elongated foot member pivotally secured at each end thereof to the free ends of the tube members of the first and second struts;

d. an elongated shoe bracket for attaching to a person's shoe and having each end thereof pivotally secured to the free ends of the sleeve members of the first and second struts, said shoe bracket being disposed parallel to the foot member;

e. yieldable means operably connected to the sleeve member of first strut, and actuator means rigidly connected in the sleeve member of the second strut, said actuator means being operably connected to the yieldable means for cushioning and restructing the pivotal movement of the struts with respect to the foot member and shoe bracket;

f. an elongated leg attachment means secured at one end thereof to one of the sleeve members, the opposite end of the leg attachment means being provided with a leg pad whereby upon lengthening or shortening the telescoping struts, the leg attachment means will retain the same relative position with respect to the shoe bracket without any adjustment thereto.