Portable seat such as for use in hunting and photography

An apparatus, method, and system of supporting a person such as a hunter or photographer in a seated position includes a cantilever arm extending from a supporting structure and a seat that is eccentrically mounted to the cantilevered arm. The cantilevered arm and eccentric seat can be attached to a supporting structure to allow the cantilever arm to pivot at its end opposite its seat over a range. Optionally the seat and cantilevered arm can be cinched along a tree or other vertical structures, placed on ground supported structure, or on other elevating structures.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a portable seat and, in particular, a seat that can be utilized with a variety of bases or supports such as a tree stand mount, single or double ladder mount, tripod or on-ground mount, or others. The present invention also relates to hunting seats, in particular seats that can be suspended from a support such as a tree trunk or ground support, allow a hunter or other person to sit on the seat, and have some ability to efficiently and effectively change positions for different shooting angles.

Problems in the Art

It is desirable to have a sturdy seat that is useful for out-of-doors and reasonably portable for a variety of applications. One example is hunting. Hunters and photographers need to sit still for sometimes long periods of time. They also need a stable support for firing a weapon or triggering a camera from a seated position. Such seats must be able to support a wide range of body types and weights. They must be robust enough for outside use over a range of environmental conditions. Additionally, it is usually desirable they be economical to make and use.

A number of different styles of hunting tree stands of this general type are known. Examples include U.S. Pat. Nos. 5,009,283, 5,131,496, 5,439,074, and 5,482,137, each of which is incorporated by reference herein in its entirety. There are even more varieties in the marketplace commercially available from many sources.

The inventor has discovered the benefit of being able to have some degree of freedom of movement while being seated. It can create problems to have a fixed-in-place seat when a hunter or photographer needs to shift aiming position.

Others have tried to provide some degree of freedom of movement. U.S. Pat. No. 5,009,283 has a seat that is adjustable in vertical height. U.S. Pat. No. 5,131,496 has an L-shaped arm that can pivot around a vertical axis near the point of support (e.g., at the perimeter of the tree). U.S. Pat. No. 5,439,074 has a chair back seat that pivots around a substantially vertical axis. U.S. Pat. No. 5,482,137 does likewise.

Other attempts are more complex. U.S. Published Application No. 2009/0321186 has two arms and a seat which pivot around vertical axes. This allows seat82to pivot around its basic center point but allows arms78and80to either be folded back up against the tree or extended fully out.

It has been found by the inventor, however, that mere pivoting around the center axis of the seat has some limitations. And, the greater flexibility of the two arm arrangement of U.S. 2009/0321186 is somewhat difficult to accurately articulate. Sometimes the two arms fold in the right direction; sometimes they do not. It also is quite complex in structure and costly. There is also some concern over how well it supports the full weight of a person in the fully extended position.

As can be appreciated by those with skill and experience in hunting and photography, factors including but not limited to ease, flexibility, smoothness, and efficiency of movement from a seated position can be extremely beneficial. Therefore, there is always room for improvement along these lines. It would be beneficial to have good control over freedom of movement in a seat while being supported either elevated or on the ground but also promote smooth and low effort operation, with minimal movement to achieve different directional tasks. Less movement to turn to different orientations while seated can result in better hunting or picture taking.

The inventor has therefore found there is room for improvement in the art.

A number of attempts at practical hunting seats have been commercialized and/or applied for patenting. Competing interests include cost, weight and size, security of mount to the support, and freedom of movement of the hunter once seated. As appreciated by those skilled in the art, sometimes these stands are mounted several tens of feet in the air on trees or ladders. Thus, weight and size are practical considerations. Complexity is also, because at such height, they must be easy to transport up to the height and install and operate.

The present inventor innovated by experience and trial and error at balancing these factors to, in particular, achieve better ability to change position while seated. U.S. Ser. No. 14/020,055, filed Sep. 6, 2013, incorporated by reference herein and commonly owned with this application, presented an elegant solution. A single cantilevered arm from a backbone that could be mounted to tree trunk or ladder or other support has an eccentrically mounted seat at its distal and. Because the center of the seat is offset from the eccentric pivot point at the end of the arm, it was discovered that a seated hunter could more smoothly and quickly change aiming position around that pivot axis. Many times in hunting or even photography, not only is change of position important but the smoothness of moving from position to position. The center of mass of the hunter or photographer typically near the center of the seat is offset from the pivot axis and results in more intuitive tactile sense of which direction and how far to rotate which then translates into much more smoother change in rotational position.

The inventor has continued to innovate in this area. As discussed in the incorporated by reference co-owned application, a further goal for smoothness of rotation with the eccentric seat is the ability to confirm the cantilevered single arm is horizontal or level. As disclosed there, a level can be built-in to the arm or seat. A minute adjustment can be built-in between arm and backbone. Once backbone is secured to the support, the operator with a single manual member can tweak the arm position towards and to horizontal or level with that adjustment.

Furthermore, the inventor has discovered that in normal use the eccentric seat and arm and backbone must support a range of user masses. A typical range might be from 50 pounds such as a child up to over 300 pounds. This can be achieved with selection of the robustness of the materials of the backbone and arm and seat as well as how the seat is mounted to the arm. The inventor has innovated different new options on that point.

Thus, the primary object, feature, aspect, or advantage of the present invention are variations and options relative to the eccentric seat of U.S. Ser. No. 14/020,055.

SUMMARY OF THE INVENTION

It is therefore a principal object, feature and advantage of the present invention to provide an improved seat of this type that solves the problems or improves over deficiencies in the state of the art.

Other objects, features, aspects or advantages of the present invention include a seat that is relatively portable and can be used with a variety of supporting bases, either from a horizontal surface or a vertical or elevated structure, which:a. provides a substantial degree of freedom of movement for the user relative the base;b. is robust;c. is relatively economical to make, assemble, and use;d. is advantageous for hunting or photography or other uses;e. can provide change in direction or orientation of a person on a seat with efficient and sometimes less movement;f. can provide effective and efficient change of orientation or direction of a person on a seat in a smooth and effective manner;g. has flexibility as to how it is supported vertically along some elevating natural or manmade structure or supported on the ground by some natural or manmade structure;h. can be used in single seat mode or in plural seat mode;

In one aspect of the invention, a portable seat assembly comprises an elongated arm having a proximal end pivotally attached to a base and a distal end, a seat mount pivotally attached to the distal end of the arm around a second pivot axis, and a seat mounted on the seat mount eccentrically from the second pivot axis.

In another aspect of the invention, the elongated arm is pivotal in generally a horizontal plane over a range of movement while the seat is eccentrically rotatable around a generally vertical axis. One benefit of the seat is it allows a user to pivot around his/her feet instead of having to move the person's feet around the person. This can allow movement in a variety of different directions on a much smaller area or platform. This can be beneficial for cost, portability, and ease of use.

In another aspect of the invention, the portable seat assembly includes a second elongated arm pivotally attached to the base and a seat eccentrically pivotally attached to the distal end of the second arm around a pivot axis.

In another aspect of the invention, the portable seat assembly includes adjustment features to assist in mounting it at or near horizontal.

In another aspect of the invention, the portable seat assembly can be combined with such things as tree stands, ladders, tripods, and shooting sticks.

In one aspect of the invention, an eccentrically mounted seat on a single arm extending from a mounting bracket includes a manual adjustment for leveling the arm and thus the seat for improved operation. In one example, the arm pivots in a first plane relative the mounting bracket to allow horizontal pivoting of the arm when installed. The mounting bracket includes a manually adjustable member to adjust the mounting angle of the bracket to the support. The support can include but is not limited to tree trunks, ladders, scaffolds, or other elevating structures. By being able to adjust the angle of mounting of the mounting bracket relative the support in a vertical plane, the arm and thus the seat can be leveled in the horizontal direction.

In another aspect of the invention, different options and alternatives regarding mounting of a seat eccentrically to a single arm are presented. It can include a single molded or fabricated seat and pivot that results in an eccentric pivot mounting at the single arm. It also could entail pivot members that extend into the seat through its edge, mount on top of the seat or in a channel on top of the seat, or clamped to the edge of a seat as a few examples.

These and other objects, features, aspects and advantages of the present invention will become more apparent with the accompanying specification.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Overview

For a better understanding of the invention, a detailed description of exemplary embodiments according to aspects of the invention will now be set forth. Frequent reference will be taken to the figures. Reference numerals will be used to indicate certain parts and locations in the figures. The same reference numerals indicate the same parts and locations throughout the figures, unless otherwise indicated.

Some exemplary embodiments are shown and described in the context of a tree-mounted seat where a mounting mechanism14/16/18mounts along the trunk of a tree as an elevating base or support. It is to be understood that the invention can be applied to other bases or supports. For example, principles of the tree-mounted seat can be incorporated into a vertical ladder. Other examples would be a self-supporting vertical double ladder, some sort of a chair base (including portable quad-legged or tripod bases), or scaffolds. Other examples include attachment of base14to a tree stand (a stand mounted high up in a tree that allows a hunter to stand). A variety of such are commercially available. Base14would simply have to be configured to bolt or otherwise fasten securely to such a tree stand. Alternatively, the strap(s) and cinch members16,18ofFIG. 1could be used to secure the exemplary embodiment seat assembly along a tree trunk or other vertical structure at the level of a tree stand. Another example could be attaching base14to some sort of ground supported base, chair, or tripod in a hunter's blind.

A main feature of the exemplary embodiments is a generally horizontal arm20having a first vertical pivot axis Y1at the base and a second vertical pivot axis Y2at or near an opposite distal end. The seat is mounted to a plate or other support that rotates about vertical pivot axis Y2at that distal end of the generally horizontal arm. The seat's center is offset or eccentric to that second vertical axis Y2. Therefore, not only can the horizontal arm20pivot side to side over an angular range relative vertical axis Y1for one degree freedom of movement, seat12itself can rotate around second vertical axis Y2in an eccentric way for a second degree of freedom of movement. Such rotation of seat12around axis Y2can be 360°. It has been found that this allows the seat to be rotated between positions over horizontal arm20(to kind of collapse the device to its smallest size) and then away from being over arm20(to extend not only side-to-side but out and away). It can be pivoted away from the arm in either direction for a number of positions. Such positions can be achieved quickly, smoothly, and easily for beneficial flexibility to the user. For example, a hunter can efficiently and quickly change positions smoothly and relatively easily, which can be important. The eccentric nature of rotation of the seat around vertical pivot axis Y2in combination with the ability to pivot horizontal arm20over an angular range relative to the tree or other support around vertical axis Y1allows the hunter or photographer to twist his or her torso to get a highly flexible range of different torso orientations without much movement of a person's lower body. This can greatly assist in smoothness and minimization of movement of the body which has obvious benefits regarding hunting and picture taking.

First Exemplary Embodiment

FIG. 1shows an example of a base or backbone14of a seat assembly10that can be mounted along a tree8with a strap16and ratchet18system. These types of bases and ratcheted straps are available from a variety of different commercial sources. Those depicted inFIG. 1are relatively small and economical, and straight forward and flexible to use. Strap(s)16can adjust for a variety of tree diameters. A seat12is mounted at the distal end of horizontal arm20which has a proximal end that is pivotally mounted to the base14. As shown inFIG. 1, a first degree freedom of movement around vertical axis Y1is at the proximal end of arm20. The second degree of freedom of movement around vertical axis Y2is at the distal end of arm20.

By referring toFIGS. 2-4, more details about specific structure of the total assembly10can be seen. Details about base14and strap16will not be set forth here as a variety of different bases and mounting straps or other structure can be used. As indicated in the Figures, base or backbone14must be of strong and durable structure and materials to support the cantilevered horizontally extending arm20and rotating seat12extending away from base or backbone14. It can be beneficial that some sort of edge or extension from base or backbone14assist in centering base or backbone14along a vertical supporting structure such as a tree8. This could include teeth or a serrated edge, or some pin(s) or spike(s) that could penetrate a tree to help hold a position (seeFIG. 2). As indicated inFIG. 1, strap16has a length that can circumnavigate tree8or other vertical supporting structure and have opposite ends that are attached to base or backbone14. Some type of ratchet or cinching mechanism18(commercially available) can be interposed along the length of strap16to both allow lengthening or shortening of its length and provide mechanical advantage to tightly cinch strap16around tree8or other vertical supporting structure. A wide variety of such straps and cinches are available so further details will not be discussed here. Examples of materials for strap16can be natural or synthetic webbing that is flexible but does not elongate along its longitudinal axis more than minimally and can again support not only the mass of the seat assembly10but also the mass of someone sitting on the seat and the forces that can be experienced in moving around. As further noted inFIG. 1, two straps16/ratchet18combinations are used in spaced apart positions along backbone14. One is possible. Eye hooks15are bolted to backbone14and can received looped opposite ends of each strap16. Other attachment methods of strap to backbone are possible.

As can be seen, arm20can be a metal tube (e.g., 1¼″×1¼″×14½″). It can be different sizes and materials.

FIG. 1shows how backbone14can be strapped and cinched along tree8. Outwardly extending cantilevered arm20extends from backbone14. Rotating seat12(rotational in generally a horizontal plane around axis Y2) is mounted at the distal end of arm20. Arm20can pivot (see arrow inFIG. 1) over a range in a generally horizontal plane around axis Y1.

FIG. 2shows the structure that allows this combination. Backbone14includes an elongated tubular member50(1¼″ by 1¼″ by 15″) having what will be called a top claw52at one end and a bottom claw54at the other. Claws52and54have teeth or serrated backward extending edges that can bite into tree8.FIG. 2shows them having essentially a serrated or toothed straight edge. Alternatively, it can be slightly curved in a convex or concave manner. Still further, it could be V-shaped to help center the backbone14on the tree. Other shapes or configurations are possible.

Another feature of tube50is an opening along its front side through which can be seen a bubble level56mounted inside tube50. Bubble level56can be mounted transversely and thus help the user install backbone tube50and align it along a vertical plane even if tree trunk8is not vertical. It can be important to mount backbone14as vertically as possible to promote the best freedom of movement pivoting in rotation of arm20in seat12.

FIG. 2shows further that in this embodiment, eye hooks15for straps18can be separate pieces that are bolted through tube50as shown. Alternatively, they could be welded in position or mounted or attached in other manners.

FIG. 2also shows that cantilever arm20can be mounted at different positions along tube50. In this example, three sets of openings51along tube50allow a bolt/T-handle46to be extended through ears43and44of bracket40when holes45and ears43and44are aligned with a set of openings51in tube50. A nut39can receive the threaded end of bolt/T-handle46to secure cantilevered arm20at that position. It is to be understood that just one set of holes51and tube50could be used or more than three. Still further, bracket40or, for that matter, arm20could be welded or rigidly fixed along tube50.

A nut can be welded on the lateral side of ear43around hole45. In that fashion the threaded end of T-handle46can be threaded into the nut. That nut can be a nut39welded or not, or bore45can be threaded to receive the threaded end of T-handle46. An enlarged portion along T-handle46would abut the lateral side of ear44when threaded end of T-handle46is threaded into nut39or threaded bore45. Further turning of T-handle46would pull ears43and44together for a tight fit on opposite lateral sides of tube50. It would basically squeeze together ears43and44to clamp against tube50. This can be beneficial as opposed to simply putting a cotter, key or pin through an unthreaded end of T-handle46to secure in place. The clamping or squeezing action can not only help structurally but can reduce noise caused by shifting of a person on the seat, which can be a beneficial feature in hunting or outdoor photography situations. But, alternatively, nut39could be separate or opening45and ear43could be threaded which would eliminate the need for nut39.

FIG. 2also shows that bracket40includes horizontal plates41and42that are spaced apart and from which ears43and44extend rearwardly. Plates41and42have an aligned set of openings47. Bolt26can extend through those openings47when a set of openings at the proximal end of cantilever arm20are aligned to secure cantilevered arm20to bracket40but allow pivoting around bolt26(which also would define vertical axis Y1). Bushings28(brass, nylon, or other) could fit on opposite sides of the proximal end of arm20between those surfaces and the interfacing surfaces of plates41and42to be bearing surfaces for pivoting of arm20. Nut29would hold bolt26in place.

FIG. 2also shows that nylon, rubber, brass, or other material bumpers or rollers48could be fastened by bolts and nuts through openings49in plates41and42on opposite sides of arm20. They would essentially act as mechanical stops to define the range of side-to-side pivoting motion of arm20.

Thus,FIG. 2illustrates how generally horizontally extending arm20could be mounted to bracket40and then bracket40mounted to various positions along tube50of backbone14for one type of adjustability of the assembly10.

FIG. 3shows another aspect of adjustability. Sometimes whatever structure bracket40is attached to is not perfectly vertical. A threaded nut58can be included on bracket40. Alternatively, it could be a threaded bore in bracket40. Here it is at the bottom along a generally vertical wall spanning ears43and44along the underside of lower horizontal plate42. A threaded bolt59can be threaded through that threaded nut or bore58(it could simply be a nut welded or fixed to bracket40) such that the threaded stem of bolt59can extend towards tube50. That end of bolt59can be moved inwardly by turning bolt59until it abuts the front facing side of tube50. As indicated inFIG. 3, this allows the angle of cantilever arm20to be adjusted in a vertical plane relative to the front face or longitudinal axis of tube50. As shown in solid lines inFIG. 3, if tube50is perfectly vertical, bolt59would be threaded in until it comes into abutment with tube50when arm20is horizontal. Even if tube50is not precisely vertical, this can hold arm20horizontal. As indicated inFIG. 3, arm20can have openings on one or more faces inside of which a bubble level22is mounted in view. This would allow the user to have an easy and immediately perceivable indicator of when arm20is horizontal.

FIG. 3also shows in ghost lines that if tube50is oriented other than vertical, arm20can be moved to horizontal (e.g., by viewing level22) and then bolt59threaded inwardly or outwardly until it comes into abutment with the front facing side of tube50. This would also hold arm20in that horizontal leveled position even though backbone tube50is not. This is another level of adjustability to try to keep arm20horizontal for better functioning of arm20and seat12.

FIG. 4shows from a top view an indication of range of side-to-side horizontal movement of arm20. Again, rollers or bumpers48(FIG. 2) would act as mechanical stops defining that range of angular motion.FIG. 4also illustrates some of the degree of freedom of movement of seat12. The left image of arm20and seat12shows how the eccentric mounting of seat12at the distal end of arm20and its eccentric mount at pivot axis Y2allows it to be rotated in that position. The other solid line image to the right is an alternative position for arm20and rotation of seat12. The ghost lines at the right then indicate how further freedom of movement seat12is possible. Bolt26extends between horizontal upper and lower plates of base14and through holes in the proximal end of tube20and is secured in position by nut29. Bushings or washers28space tube20from the horizontal plates and provide lower friction for pivoting of tube20. At the opposite or distal end of tube20through-holes24can receive a bolt34having one end fixed to the seat and an opposite lower end extending below tube20. Bushings36(e.g. brass, nylon or other) can be fitted inside tube20and bolt34extend through them. A washer37can also reduce friction. Nut35can secure that combination together. This allows attachment of the seat to the distal end of tube20but allows it to rotate around that axis Y2.

FIGS. 2 to 5A-C diagrammatically show additional details regarding seat12. A main support plate30of somewhat similar shape to the seat12has multiple apertures that correspond to four threaded receivers in the seat bottom that allow seat12to be mounted by screws31into those threaded receivers. Alternatively, seat12can be screwed or otherwise attached to bracket30. Seat12can take many configurations. In the exemplary embodiment, its bottom is essentially a wood plate with fabric and foam cushioning to form the seat and the seat back. Bolts or screws31would fix seat40to plate30. As shown inFIG. 2, bolt34, bushings36, nut35and washer37will be combined along axis Y2to mount combined plate30and seat12to beam or arm20but with the center of12eccentric or spaced from axis Y2.

As illustrated inFIGS. 4 and 5A-C, axes Y1and Y2allow seat12to be pivoted with arm20sticking straight out from the tree but the seat12pivoted back on top of and basically covering part of arm20.FIG. 4shows seat12pivoted approximately 50° either way from the straight out position ofFIG. 3.FIGS. 5A-Cshow different positions of seat12and arm20; illustrating in ghost lines a hunter. These views show the flexibility of pivoting around that one degree freedom of movement of Y2but also changing the angular direction of arm20. The eccentric mount of seat12to beam20allows high flexibility. An example would be the shooter could rotate the seat12in different directions for a left or right shot without moving the shooter's feet. If a large movement is desirable (for example to shoot behind the tree), the user's feet would probably have to move but may not have to very much.

FIG. 4illustrates that pivot axis Y2is at or near the distal end of arm20and at the very periphery of seat12. This allows seat12to be pivoted around Y2theoretically 360° of rotation. In a position where seat12is nearest the tree trunk, seat12would basically cover the top of arm20. In the farthest away position, it extends away from the end of arm20.

As can be appreciated, as illustrated in the Figures, a hunter can rotate or pivot seat12around pivot axis Y2for a variety of convenient aiming directions. This provides a high degree of flexibility of positioning for the hunter. It has been found that this off-center mounting of seat12at the end of arm20(for example, 7½″ off center from the center of seat12to the center of pivot for a 14″ diameter seat) allows almost 360° pivoting of the hunter with minimal effort and high control. The mounting base or backbone14that is cinched and clamped against the tree trunk, and the robustness of arm20and its connection to base14, allows support of hunters of several hundred pounds or more. Essentially, there are two degrees freedom of movement of the hunter based on just a single arm20at a pivot axis at or near base14.

Importantly, embodiment10not only provides these subtle combinations of user-selectable movements when the seat is attached to tree8, its setup is beneficial in that built-in levels22and56allow both vertical positioning of backbone14on tree8(e.g. when cinching it) and then (in combination with adjustment bolt59) fixing arm20in horizontal plane.

The components allow various modes of installation of assembly10. In one example, backbone subassembly14can first be strapped to tree8with reference to bubble level56for vertical alignment. Then seat12, arm20and bracket40(previously assembled), can quickly be mounted along backbone14by use of T-bolt46and simple alignment of bracket40along tube50and insertion of T-handle46. Instead of nut39separate from bracket40, it could be welded to ear43so that all the user needs to carry is T-handle46as a separate piece. T-handle46could be chained or attached in a manner to bracket40to deter its loss. Then, when bracket40is attached to tube50the user can reference built-in bubble level22on arm20and adjustable59for horizontal positioning of arm20.

Built in levels on seat assembly10allow for effective and efficient visual indication of positioning of arm20relative to ground. As mentioned, this allows the user to have a visual reference while manually adjusting the seat during installation for preferred positioning.

An optional feature for the hunter's seat ofFIGS. 1 to 5A-C is shown atFIG. 8. An additional rigid arm62can extend from seat support30. At the end of arm62can be a vertical receiver64(e.g., having a rubber tube inside it to receive the end of a shooting stick60). Arm62can be rigidly attached to seat support30so that it rotates with rotation of seat support30around axis Y2. Shooting stick60can be custom made or can be a commercially purchased stick having a free lower end that can fit within receiver64. As can be appreciated, arm62and receiver64can be made of different materials and configurations. It provides the ability for a vertical member such as a shooting stick, or a camera support stick, to be effectively utilized with eccentrically rotatable seat12and pivoting arm20.

FIGS. 9 and 10show an alternative possible embodiment according to the present invention. As shown inFIG. 9, this would allow a second seat with the same degrees of freedom of movement as seat12ofFIG. 1from the same base or backbone. As can be seen inFIGS. 9-11, first cantilever arm20′ would extend from essentially the same bracket as bracket40ofFIG. 2. The second cantilever arm20″ would do likewise from a second bracket like bracket40ofFIG. 2.

FIG. 11shows a modified backbone14for this optional embodiment. Similar to backbone tube50atFIG. 2, a central tube50would extend from upper jaw52to lower jaw54. Those jaws would be expanded laterally and help support similar tubes50′ and50″ spaced apart on opposite sides of middle tube50. Middle tube50can have brackets with hooks15for connecting opposite ends of a cinching strap such as in the embodiment ofFIG. 1the strap that will backbone assembleFIG. 11to a tree or other structure. Each of the tubes50,50′, and50″ could have one or more sets of apertures along their length as a mounting point for T-handle bolt46through ears43and44of a bracket such as bracket40ofFIG. 2. This allows placement of one, two, or perhaps even three seat assemblies10ofFIG. 2to the backbone ofFIG. 11. But as shown in the example ofFIGS. 9 and 10, two seat assemblies12′ and12″ on cantilever arms20′ and20″ can be mounted at opposite outer vertical tubes50′ and50″ and can operate at least partially together regarding the range of freedom of movement of the seat assembly10ofFIG. 2. It therefore can be seen that this combination provides a high degree of freedom of adjustment or movement but with relatively simple and robust parts. Bracket40can be strengthened by gussets and the materials of bracket40, bearings, bolts, backbone14, and arm(s)20can be selected to support a wide range of weights, on the order from under 100 pounds to over 300 pounds or more. By appropriate selection of materials and their preparation (e.g., painting, galvanizing, and the like), they can be ruggedized for outside use. Likewise the fabric cover of chair12can be ruggedized for outdoor use.

Again, as can be appreciated by the foregoing, the combination of freedom of movement features of seat assembly10promotes efficient and effective adjustment of orientation of a person on seat assembly10. For example, as illustrated inFIGS. 5A-C,6,7A-C, and8, a hunter can quickly, smoothly, and efficiently change positions over a substantial range over a very small area. The eccentric seat allows pivoting around the person's feet instead of having to move the feet around the person. This allows efficient movement in a much smaller area or platform which can be substantially beneficial.

Options and Alternatives

As can be appreciated, arm20and seat12can be mounted to other bases. This can include a ground mounted chair-type base, a ladder on the ground, a ladder supported to a tree, in a hunting blind, on a vehicle, or the like. The mounting should be robust enough to support the seat for its intended use and its degree of freedom of movements.

Seat Support Variations

FIG. 6illustrates this concept. A ground supported chair70could include a center vertical post71to which backbone14could be strapped or cinched. Alternatively, vertical support71of chair70could simply have bracket40attached to it along its length. Outwardly extending legs72would provide ground contact in support for the chair. A still further optional feature would be instead of connecting arm20to bracket40with less than 180° side-to-side angular range of motion, arm20could be attached to center tube71to allow 360° rotation or at least over 180° as shown. This, in combination with the eccentric rotation ability of seat12on arm20, allows for the types of change in upper body orientation of a hunter as shown inFIG. 6.

Foot Rest Options

FIGS. 7A-Cshow additional alternative or operational features according to aspects of the invention. The lower end of backbone14could be attached a foot rest80(essentially a tree stand). This can be beneficial especially when seat assembly10is mounted off of the ground such that the user's feet do not touch the ground.

Foot rest80in this embodiment has an outer tubular metal frame81, cross bars of tubular metal83and then metal mesh82fixed to or over those structural members. As can be appreciated fromFIGS. 7A-C, foot rest80could be placed at the bottom of backbone14or it could replace the lower jaw54ofFIG. 2with a V-shape at the back of foot rest80. Still further, that V-shape back edge could include a serration, teeth, or other projections to help stabilize it.

Still further, backbone tube50could have multiple sets of openings at the lower end to allow for different mounting positions of foot rest80relative to the plane of seat12. This could be another adjustment feature that could be varied according to need or desire. For example, different height hunters might want foot rest80spaced farther apart from seat12than shorter members. Additionally, the method of attachment of foot rest80to backbone tube50could vary. It could be hingeably adjusted so that it could be folded up against backbone tube50. Other supporting members could be used such as cables that would extend from backbone tube50out to the opposite left and front distal edges of frame81(see cables84shown diagrammatically inFIGS. 7A-C). The mesh82can be beneficial as it allows hunters or photographers to see down through foot support or deck80. It could be expanded metal, or other materials and configurations sufficient to support the weight and forces of a range of conventional sized persons wanting support of this type. Another example would be a solid foot support platform with apertures through it.

Weight-saving features can be built into the assembly. As shown inFIGS. 1-3, apertures or openings23can be formed along arm20to reduce weight. Similar effects could be made for other components without sacrificing needed structural characteristics.

As indicated earlier, built-in bubble levels or analogous components can provide easy direct visual feedback for helping the user to plum vertical backbone as close as possible (sometimes it is not trivial to do depending on the nature of the tree or elevating structure and its verticality or not), as well as the fact sometimes these adjustments are being attempted at tens of feet in the air. It can help get it as plumb as possible. Bubble level in cantilever arm20can be used in a similar manner to get the arm20as close to horizontal as possible.

Foot Support

Another possibility for foot support80is that it be attached to essentially a complimentary tube that could be slideably inserted in the lower end of backbone tube50and fixed into position by a cross bolt or pin such as T-bolt46ofFIG. 2. See alsoFIG. 8. As mentioned previously, there could be multiple sets of matched apertures along that extended slidable tube that would allow for different spacings of the foot support80relative to the seat50.

Seat and Assembly

It can furthermore be appreciated that in one form all the features described herein could be possible in a single assembly10. The customer can purchase seat12. It could be mounted along a tree or pole at or near ground level where the hunter can simply stand on the ground to get on and off seat12. Or it could be mounted higher up along the tree where the hunter would need to utilize a ladder or the like to reach that position, install seat assembly10and utilize it.

Seat assembly10could be sold alone or with options. A kit could include seat assembly with backbone tube50with claws52and54. Claws52and54could be removable or a different backbone50sold with the kit for use, for example, for mounting on a ground support, such as a chair or tripod.

Ladder Mounting

Still further, a feature that could be utilized with the basic concept of eccentric seat12and pivotable arm20is mounting tube50along the side of a ladder. By reference toFIGS. 12-15, one example of a ladder110is shown. The features of ladder110include that it can be broken up into sections for easier transport and storage, it can have a ground-contacting foot assembly that can be adjusted for various terrains (see pointed ends127at angled telescoping tubes126and124. Tubes124and126can be locked into different extended positions by T-bolts129(two a side) that thread through threaded bores in tubes124and bite into tubes126). The angling of tubes124and126(approximately 45°) relative to the longitudinal axis of ladder110is a stabilizing feature. It provides a spread base (wider than the ladder rails). It can have bubble levels180and182to help vertical orientation.

FIG. 13shows how multi-section ladder assembly110ofFIG. 12can be extended along a plane from a bottom leg end to a top end. One or more seat assemblies10with or without foot rests80can be installed along the ladder. Bottom legs (telescoping tubes124and126) at 45° opposite angles to the longitudinal axis of the ladder, have pointed distal ends127. A level180built into ladder110can help install or visually adjust legs126relative to fixed tubes124to get good vertical alignment of the longitudinal axis of ladder110. It has been found that the pointed ends127of legs126tend to penetrate and grip the ground but the 45° spread of tubes124from the ladder longitudinal axis tends to transfer the forces outwardly to deter the pointed ends127from trying to penetrate directly down into the ground. In other words, this combination tends to penetrate and prevent lateral movement of the bottom of the ladder relative to the ground but limit the amount of penetration into the ground to keep the ladder in a stable position. Legs126can be telescoped outwardly to account for uneven terrain or the like. Other angles are possible. See enlargement of the lower part of ladder110inFIG. 15. Small pieces of steel rod can be welded across one face of extendable legs126(as shown inFIG. 15) to serve as mechanical stops to prevent legs126from sliding all the way into sleeves127.

The enlarged insert inFIG. 13shows how ladder sections can be locked into position by sleeves146and T-bolts148.

FIG. 13also shows that lower stabilizing arm140, with telescopically sliding distal end, can be used in combination with level182built into ladder110. In this embodiment, a 12° divergence from plumb from the top of ladder110to its bottom end has been found desirable. Level182could be built along the ladder rail112in a position that would visually indicate a center position of the bubble in the bubble level when the ladder is at that 12° offset from plumb. This common combination with level180, would allow the installer to place the ladder in the approximate preferred position based on those two levels, adjust the lower legs, and extend and strap arm stabilizer140and cinch it by strap18around tree8. The user could climb up and also extend upper stabilizing arm140. The user could then climb further and cinch the top of ladder110with an upper strap134(FIG. 12).

FIG. 13then shows, in combination withFIG. 14, that one or more seats (herewith foot support80), can be hauled up the install ladder110and easily and quickly mounted. In this example, a backbone14would have upper and lower sets of openings that would match the distance between the pairs of openings in ear sets136and137at the ends of each cross bars135fixed along top of ladder110. T-bolts like T-bolt146could be extended through to lock upper and lower ends of tube50to the position shown inFIG. 14. Bracket40with cantilever arm20and eccentric seat12can then be mounted along that backbone, as can foot rest80. This would be the same as described earlier.

As further shown inFIGS. 13 and 14, by having three sets of spaced apart cross bars135at the top of ladder110, one seat assembly10could be attached between two such cross bars135. As shown in base lines, another seat assembly10′ could be attached between a set of cross bars135on the other side and a different set of cross bars135. This offsetting allows for balancing of two seat assemblies10on opposite sides of the ladder but also gives clearer directional line of sight for each user. It is to be appreciated, however, that the seat assemblies could be at the same level (e.g. attached to the same two cross bars135but on opposite sides). It is further to be appreciated there could be four cross bars135for additional mounting variations for the seat assemblies10. It can have stabilizer bars140along its length. It furthermore can have a cinching strap135at or near its top to hold it into position and optimally other straps in other positions. It is to be understood that the 12° angle that is preferred for the intent of ladder110relative to the vertical could vary according to need or desire. The number of sections, the length of ladder110, and other features could vary according to need or desire.

Another feature of ladder assembly110is that it can have a set of three spaced apart cross bars135, each having a set of ears136,137or other mounting receivers at opposite ends. This would allow multiple seat assemblies10to be concurrently mounted and used on the same ladder. For example, inFIG. 8, each cross bar135has a set of ears136,137at opposite ends. Those ears can be basically spaced apart vertically aligned ears having a set of apertures that correspond to apertures45in ears43and44of bracket40(seeFIG. 2). Then, with a bolt139(could be like T-bolt146ofFIG. 2), each seat assembly10can simply be brought to an end of a ladder cross bar135, the apertures between bracket40and ears136,137align, a bolt inserted and secured, and then a whole seat assembly10is mounted along ladder110. As can be appreciated fromFIGS. 13 and 14, one or more seat assemblies10can be placed on ladder110, each on a set of cross bars135. One seat could be mounted higher, and another lower bar. They can be on opposite sides to help balance. More than two could be added. As can be appreciated, ladder110for any of its features, could be utilized with other tree stands or portable seats than those of the exemplary embodiments. For example, variable tree stands or seats could be mounted along ladder110and take advantage of its self-leveling bubble levels which are built in, its bottom adjusting legs, its stabilizing arms140, or any combination of the above.

FIG. 12also shows that top of ladder110could have a V-shaped serrated jaw132to help center the top of a ladder on a tree. Strap134would work similarly to cinching strap16and cinch18ofFIG. 1.

The support arms140could simply be hinged U-shaped rigid arms that could extend from rails112at one or more locations, have a V-shaped cross member144at the ends of legs142, and cinch at that location around a tree with cinching strap134.

Ladder110can have multiple spaced apart rungs116. It can be disassembled into three sections but assembled into a unitary ladder at joints146by T-bolts148. This would allow it to be carried in three sections and then assembled and hinged up into an elongated position on site.

The adjustable feet127allow ladder to be supported as plumb as possible on uneven ground by sliding and locking legs126in place. Levels180and182can assist in finding as close to plumb and angled positions as possible. Level182can also be used to achieve the right angle of the extended ladder relative to a vertical support such as a tree. As can be appreciated just one level or both levels, could be utilized.

Spacer or stabilizer140could have arms142made of two telescoping sections that can be adjusted longitudinally (see stabilizing section140in the middle ofFIG. 8). This would allow some adjustability relative a tree or other vertical support.

Eccentric Seat Variations

FIGS. 16A-Iillustrate alternative embodiments according to aspects of the invention. They are similar to the other embodiments previously described in that they include a seat which is eccentrically mounted to the distal end of the single arm from a backbone attached to the tree or other elevating support. Thus, they each function similarly in that the eccentric rotation around the mounting vertical pivot axis provides high flexibility of positioning when a person is seated thereon.

With particular reference toFIGS. 16A-I, the basic eccentric seat on a single cantilever arm like disclosed in U.S. Ser. No. 14/020,055 is set forth with the following main differences.

The seat ofFIG. 16Ais a molded plastic or cast aluminum single piece. Other materials or combination of materials are possible. Bushing101would fit over a vertical pivot stub120extending out of the distal end of arm20. Short portion102would extend away from bushing101and underneath a seat portion103. A built-up section104structurally supports the broader seat103. By appropriate design, and selection of materials and manufacturing processes, such a combination is a single piece but could support the normal range of weights of users. Also, accessories discussed regarding prior embodiments can be used with it. Seat103has its perimeter at or near pivot axis Y2(the eccentric pivot axis like earlier embodiments), but can be one molded or formed piece that rotates about that axis eccentrically. As will be appreciated, variations are possible. Instead of stub120on arm20rotatably journaled in bushing101, the bushing could be in arm20and a stub or axle depend from seat portion102into it for similar eccentric rotation. The bushing could be interior of arm20or external, or on its end.

Likewise, the form factor of the seat portion103can vary according to need or desire. The specific form factor of the connecting portion102and built up portion103can vary, as can that of the seat itself. A cushion or other material, layer, or add-on can be added to the seat top surface.FIG. 16Ashows in dashed lines diagrammatically at reference number105such an option of attaching or mounting another layer above portion103. An example would be a cushion or similar that would have a cushioning ability or a higher coefficient of friction than plastic or metal. It could be fastened in any of a number of ways. Non-limiting examples are adhesive, rivets, bolts, ties, and any combination thereof.

This combination provides the equivalent of a bracket from the pivot point or axis Y2that has sufficient structural features to support in a cantilevered manner the seating surface.

Seat103ofFIG. 16Ais a single piece. It includes the seat portion and integrated pivot member at or near the periphery of the seat. That pivot member can fit into a bearing or other connection at or near the end of the cantilevered arm. Eccentric rotation of the seat around pivot axis at the end of the arm like that of U.S. Ser. No. 14/020,055 is possible.

As can be appreciated, the single piece seat and pivot member can be made in a variety of ways. One example is a single piece of cast or molded metal. Aluminum is one possibility. The designer would design the form factor of all of those portions to support a reasonable range of forces and weights that would sit on the seat. In this example, the mounting member is a downward extending member that would seat into the end of the arm but allow rotation around that axis.

Some advantages are that there would be no assembly of the integrated seat. The whole thing could be removed and mounted easily. There could be a bolt through the bottom into a female threaded bore in the pivot member to retain it in position on the arm. Other mounting techniques are possible.

The seat could be manufactured to have a flat top surface or some sort of formed features (raised and/or indented) according to need or desire. It could also have a seat cover that would be integral or added. One example of a seat of this type would be cast or molded aluminum of approximately one or several inches average thickness across the seat.

As can be seen, the downward extending member104can be at or near or offset from the center of the seat portion103. It could also be at or near the perimeter of the seat portion103. The seat portion103can also have some asymmetry but the pivot mount is eccentric from its general center.

FIG. 16Bis similar toFIG. 16Abut shows a different form factor for a one-piece seat and pivot. Instead of portion101and104ofFIG. 16A, seat portion103is directly laterally connected to the bushing101. There could be buttresses or built-up portions106between the bushing101and seat portion103for structural support of this unitary member. Again, it could be molded or otherwise formed of any of a variety of thermoplastics. It could be cast or extruded out of metal. It could even be formed of other materials such as wood. The material and manner of making is not limited to these examples.

Again, however, this combination is a one-piece unit mountable to the pivot at the end of the single arm20like the other embodiments and allows eccentric pivoting at that distal end around axis Y2.

FIG. 16Cshows an additional alternative embodiment to those ofFIGS. 16Aand B. The seat portion103can be connected to the bushing101through some buttress107or combination of several buttresses that extend across at least a portion of the bottom of the seating surface103. Again, this can all be made of one piece. Alternatively, however, it could be multiple pieces.

Another feature indicated onFIG. 16Cis a level, see dashed lines at reference number108. It could be placed anywhere along the structure including away from bushing101and be positioned to allow the user to quickly look to see if the plane of the seating portion103is indicated to be at or near horizontal when the whole assembly is installed in operable position (such as along a tree trunk, on a ladder, or on some other elevating support). This can help the eccentric rotation and functions of that seat to perform better, as discussed earlier. As will be appreciated by those skilled in the art, the level can be placed anywhere that is practical on the seat. It could be built-in to the seat or any part of it so that it is flush with the surfaces it is mounted in or recessed. It could alternatively be a surface mount. There could be one or more. As mentioned earlier, one or more levels could be alternatively placed on the single arm which would give a general indication of whether the seat also is horizontal. There could be multiple levels, at least one to indicate horizontal position and one for vertical alignment (or misalignment), and/or offset from other reference directions including non-vertical and non-horizontal. At least one level can be used with any of the embodiments herein.

FIG. 16Dshows an alternative embodiment. An L-shaped structural member110has its shorter end inserted in bushing101on arm20. Its longer end extends laterally. A seating portion can be mounted on, over, around, or under it. The long portion of the L-arm110is a structural support for the seating portion103. Number110can be metal or other strong rigid material to support the range of weights of typical users. Seat portion103can be molded around it, affixed to it, or otherwise mounted on it. As the other embodiments, this assembly rotated eccentrically around axis Y2.

FIG. 16Dshows the L arm has a downward extending member that would fit in the arm. A horizontal member could fit into an opening in the edge of the seat and extend potentially most of the way through the interior of the seat for robustness. The seat could be wood, metal, thermoplastic, or other materials robust enough for the intended use. The L-arm could be metal but possibly other materials, again if robust enough for the intended use.

The L arm could be installed in a different manner. It could have the horizontal extension that fits into a slot through the top of the seat and part of the sidewall and/or just along the top of the seat or otherwise. It could be recessed to present a smooth surface. Alternatively, a cover member could be placed over that horizontal part to present a smoother seating surface.

Another L arm version could have a clamping member at its distal end of its horizontal portion. That clamping member could clamp onto or at the perimeter of the seat member. It could be secured by clamping converging interference fit forces and/or bolts, screws, or other fasteners. Again, a cover could be placed over the whole top or part of it. Or the clamp could be recessed into slots on top and bottom of the seat portion.

FIG. 16Eshows an embodiment where single piece seat portion103has a receiver, bore, indent, or the like110eccentric to the general center of seat portion103to receive an end of axle112. The other end of axle112can rotatably journal in bushing101at the end of arm20along axis Y2. In this embodiment, receiver110has a square shape to receive a square, complimentarily shaped-end of axle112. This would prevent rotation of axle112relative to seat portion103. But the other end of axle112(here round in cross section) would complimentarily fit in bushing101and allow free pivoting of seat103and axle112relative to arm20. This embodiment allows a very simple form factor for seat portion103, including of one-piece.

FIG. 16Fshows single arm20with a through-path122at or near its distal end. Bearings or other structural components can be used to facilitate rotation of a stem120extending eccentrically from seat103. Stem120would mate into through-path122(and any bearings or bushings) and be rotatable therein. Stem120and seat103can be one piece (e.g. molded plastic, shaped metal, or otherwise).

FIG. 16Gshows another configuration for an L-arm134having the 90-degree bent end fit into through-path132in arm20, and its other end inserted into a partial or full bore130in seat103. The L-arm could alternatively have a polygonal cross section and mate into a complementary polygonal bore130to prevent rotation of seat103around the inserted end of L-arm134. Other ways to secure L-arm134to seat103(e.g. bolts, screws, adhesive, or other) are possible.

FIG. 16His similar toFIG. 16Gbut shows the variation that a slot136in seat103can receive a portion of the L-arm134. It can be secured by fasteners138or fastening techniques. Slot136could be in the top or bottom of seat103.

FIG. 16Iis similar to the other L-arm versions but is secured to a seat103by a U-shape (spaced apart and generally parallel sub-arms135top and bottom at the distal end of L-arm134). Seat103could slide between sub-arms135and be fastened. Alternatively, sub-arms135could be configured to clamp opposite sides of seat103, interference fit, or otherwise be secured.

For all these embodiments, the materials can be selected to meet the requirements of the application. And these embodiments are non-limiting to other variations and configurations.

As will be appreciated, one aspect of the invention is a tree stand type seat allowing rotation of the user on a single arm supported in an elevated position. And a fixed, mounted, or built-in level allows for easy checking if the seat or arm is generally horizontal for best operation. The mechanism to support the device on the elevating structure can be configured, adjusted, or mounted to obtain this horizontal position. This eliminates guessing or eyeballing, which can be inaccurate.

With particular reference toFIGS. 17A-D, an alternative way to level the single arm with eccentric-mounted seat is shown. It can be used with any of the above options for an eccentric seat on a single cantilevered arm, or those suggested and disclosed in U.S. Ser. No. 14/020,055.

A bracket40′ similar to bracket 40 of Ser. No. 14/020,055 (seeFIG. 2herein) is between arm20and backbone50′. It mounts arm20to the supporting member/backbone50′. That bracket40′ is basically two spaced-apart flanges41′ (top) and42′ (bottom) that receive the proximal end of the single arm20in a manner that allows that arm20to be swung over at least a substantial range relative to the backbone50′ in a horizontal plane or near thereto when installed in operable position. This allows the user not only to spin on the eccentric-mounted seat but also move the distal end of the arm over a substantial range in a horizontal plane. But additionally, top flange or plate41′ has a toothed concave edge to center the device on a tree trunk and bite into the wood, similar to flange52or54ofFIG. 2.

In U.S. Ser. No. 14/020,055 (andFIGS. 2 and 3herein), the arm20can be leveled relative to horizontal by adjusting the arm20and mounting bracket40combination relative to backbone50by adjustment screw or bolt59that changes the angle of bracket40to backbone50. That requires that bracket40be pivotable in the plane along the long axis of backbone50(along the axis of T-member46. Therefore, backbone50can be cinched or otherwise secured along a tree trunk (or to some other elevating structure). Because a tree trunk or other elevating structure may not be perfectly vertical or the mounting of backbone50not perfectly vertical, arm20would not be horizontal. Therefore, bolt59can be turned in or out to change the angle of bracket40to backbone50. Level22(or other techniques) allow arm20to be leveled horizontally if within the range of adjustment of bolt59. Level22can be a bubble level to visually show offset from backbone50′ for 360° around its center. Another level type or multiple levels there or in different locations on backbone50′ and/or arm20are possible. This is allowed because bracket40is pivotable relative to backbone50along the horizontal axis through aligned openings45in bracket40(which is pivotally fixed to backbone50by T-bolt46, seeFIGS. 2 and 3).

In this embodiment ofFIGS. 17A-D, that adjustment can be left out. There is not pivotability of bracket40′ (or plates41′ and42′) relative to backbone50′. They are fixed relative to one another. Instead, leveling of the arm20is accomplished by a manual setscrew or threaded member59′ on top cross beam51′ of backbone50′ itself, as shown in ofFIGS. 17A-D. Essentially setscrew59′ allows adjustment of the angular orientation of the backbone50′ relative to the tree trunk or other support on which the whole seat assembly is mounted. That adjustment59′ adjusts the angle of backbone50′ relative the tree or other support, which thus automatically adjusts with it the angle of the arm20in a vertical plane. This therefore allows leveling of the arm to horizontal (within the range of adjustment of member59′ for benefit of operation of the arm and seat.

As shown in ofFIGS. 17A-D, setscrew59′ basically is a threaded member with a T-handle. The opposite end57′ can be blunt, pointed as shown, and/or have a nut or other built-up or enlarged portion. With a tree trunk, a pointed end57′ helps dig into the tree for a fixed position. The nut or enlarged portion inward of end57′ can act as a mechanical stop so the point57′ does not dig deeper into the tree. The configuration of backbone50′ includes top or upper plate41′ with serrations to bite into the tree at its location. Then the pointed end57′, being spaced below plate41′, is a second abutment with the tree trunk. But since it can be extended or retracted relative to backbone50′, it adjusts the tilt of backbone50′ relative to the tree (or other elevating structure). Arm20pivots relative to backbone50′ around axis Y1(just like the embodiment ofFIGS. 2 and 3). And seat12(shown inFIG. 17B) is eccentrically rotatable around axis Y2like the embodiment ofFIGS. 2 and 3). But arm20does not pivot up and down relative to the long axis of backbone50′. Therefore, angular adjustment of backbone50′ relative the tree trunk or other elevating structure automatically changes the angle of arm20relative to horizontal. The user threads adjustment bolt59′ in one direction or another to adjust the angle of the backbone50′ to, in this case, the tree. It also could be adjusted in a similar fashion if mounted to a ladder or other elevating support. By that simple adjustment, and optionally using a small level22(bubble or otherwise) or a built-in level such as disclosed in U.S. Ser. No. 14/020,055 (seeFIGS. 3 and 16Cherein), the user simply levels out the arm20in a different way than shown in U.S. Ser. No. 14/020,055. The other features, including cinching backbone50′ to a tree with strap16and ratchet tightener18(with opposite ends of strap16secured to bolts54′L and54′R on bracket40′), and range of movement in a generally horizontal plane around axis Y1and eccentric rotation of the seat portion around axis Y2are the same or similar to other embodiments. As will be appreciated, once the overall device is preliminarily cinched to a tree trunk, and the serrated edge of top plate41′ is against the tree trunk, the masses of cantilevered arm20and seat12will rotate the bottom of backbone50′ into the tree trunk. This urges point57′ of T-bar screw59′ into the tree trunk. Thus, adjustment of screw59′ can adjust the verticality of backbone50′ which in turn adjusts arm20relative to horizontal.

It can be appreciated that variations obvious to those skilled in the art will be included within the invention. The invention can take many forms and embodiments. The materials, the exact dimensions and configurations can vary according to desire or need.