Abstract:
A tree climbing apparatus which includes a climbing platform for supporting a hunter on a tree and a cooperating foot platform for engaging the tree beneath the climbing platform and intermittently supporting the hunter while the climbing platform is caused to ascend the tree. The front ends of a pivoting cable adjusting guide bar and a pivoting cable retention guide bar, respectively, are slidably mounted for lateral and medial displacement on opposite sides of each platform at the front end thereof. One end of a support cable or chain is attached to an adjusting handle slidably and adjustably mounted on the cable adjusting guide bar and the opposite end of the support cable is extended around the tree and removably secured to the cable retention guide bar. Sliding the adjusting handle rearwardly on the platform tightens the cable around the tree to secure the corresponding platform on the tree at a selected height and the tightening cable pivots the front ends of the cable adjusting and cable retention guide bars inwardly on the platform to tighten the cable around the sides of the tree. Sliding the handle or handles forwardly loosens the cable to facilitate descension of each platform on the tree. By alternately standing on the secured foot platform while raising and securing the climbing platform and sitting on the climbing platform while raising and securing the foot platform, the hunter gradually works his or her way up the tree.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of copending U.S. Provisional Application Serial No. 60/118,536, filed Feb. 4, 1999. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to an apparatus for ascending and descending trees for deer hunting and the like, and more particularly, to a tree climbing apparatus characterized by a portable tree climbing platform and a cooperating foot platform, both of which engage a tree for supporting a hunter on the tree, with the climbing platform located above the foot platform. The hunter alternately stands on the foot platform and lifts and secures the climbing platform on the tree and then sits on the climbing platform to lift and secure the foot platform, in order to gradually work his or her way up the tree. Both the climbing platform and foot platform are fitted on the front end of each with tree-engaging members, or blades, for engagement and disengagement with the tree. In a preferred embodiment of the invention the rear ends of a cable adjusting guide bar and a cable retention guide bar, respectively, are pivotally attached to the rear end of each platform, on opposite sides thereof. The front ends of the pivoting cable adjusting guide bar and cable retention guide bar are slidably mounted for lateral and medial displacement on opposite sides of the corresponding platform, at the front end thereof. In a preferred embodiment, one end of a support cable is connected to a sliding adjusting handle on the cable adjusting guide bar and the opposite end of the cable is extended around the tree above the tree-engaging members, respectively, and is removably secured on the cable retention guide bar of the corresponding platform. In another embodiment, a bicycle-type support chain is connected to the adjusting handle on the cable adjusting guide bar and the opposite end of the chain is extended around the tree and removably secured to the cable retention guide bar. The adjusting handle is moved rearwardly on each platform and locked in place to tighten the cable or chain around the tree and support the corresponding platform on the tree at a selected height. As the cable or chain is tightened around the tree by operation of the handle, the front ends of the pivoting cable adjusting and cable retention guide bars, respectively, slide inwardly on the frame according to the tree diameter to automatically adjust for the size of the tree and tighten the cable or chain around the tree. Each platform is caused to ascend or descend the tree, as desired, by tilting the rear end of the secured platform upwardly, thereby disengaging the tree-engaging blades and support cable or chain from the tree; raising or lowering the platform on the tree; and then lowering the rear end of the platform to again engage the tree-engaging blades and support cable or chain with the tree at the selected height. As each platform is caused to ascend the tree, the corresponding adjusting handle is moved rearwardly on the platform to tighten the cable or chain around the tree according to the decreasing tree diameter. Conversely, as each platform is caused to descend the tree, the adjusting handle is periodically moved forwardly on the platform to loosen the cable or chain around the tree according to the increasing tree diameter. The climbing platform and foot platform of this invention are light in weight and easy to manipulate. 
     2. Description of the Prior Art 
     Various tree and pole climbing apparatuses and climbing deer stands and gun platforms, in particular, are known in the prior art. Typical of these platforms is the apparatus disclosed in U.S. Pat. No. 4,168,765 to Clarence E. Ferguson, et al. This climbing apparatus includes a hand climber which is attached to a tree or pole at a point above the user and is used in cooperation with a support platform carried by the user&#39;s feet, with the user pulling himself and the support platform up the tree or pole while grasping the hand climber and subsequently supporting himself on the support platform while manipulating the hand climber higher on the tree or pole. A similar pole climbing apparatus is illustrated in U.S. Pat. No. 4,137,995 to Frank Fonte, which apparatus includes a pair of platforms, one of which supports the feet of a user and the other positioned essentially about the waist of the user, both of which platforms engage the tree or pole to be climbed. The upper platform is initially used to support the weight of the user and the lower platform is pulled upwardly while the user&#39;s weight is supported by the upper platform, to facilitate moving up and down the pole or tree. Yet another climbing apparatus is illustrated in U.S. Pat. No. 3,944,022 to Joseph W. Ming. The Ming tree climbing stand is built of rigid sheet material and includes a pair of tubular runners secured to either side of the stand and having a treecontacting end fitted with a V-notch in the center. As in the case of the Ferguson stand, this climbing platform is fitted with a mechanism for inserting the feet, and climbing is accomplished by grasping the tree, pulling the platform upwardly with the legs and subsequently using the platform to support the legs while the user facilitates another grip higher on the tree. Descent is accomplished by reversing this climbing procedure. Yet another climbing platform is illustrated in U.S. Pat. No. 3,338,332 to H. W. Brantly. The deer stand of this patent includes a U-shaped bracing element constructed in such a manner as to have a concave inner surface rest against the front of a tree; a clamping bar which can be connected to the legs of the U-shaped bracing element at the rear of the tree; a platform supported by the U-shaped bracing element and clamping bar; and braces extending downwardly at an angle from the platform, which braces engage the trunk of the tree at a point below the U-shaped bracing element. Other climbing tree stands are detailed in U.S. Pat. No. 2,775,489, dated Dec. 25, 1956, to Hagadorn; U.S. Pat. No. 4,428,459, dated Jan. 31, 1984, to Peck; U.S. Pat. No. 4,549,633, dated Oct. 29, 1985, to Merritt; U.S. Pat. No. 4,597,473, dated Jul. 1, 1986, to Peck; U.S. Pat. No. 4,726,447, dated Feb. 23, 1988, to Gibson, et al; U.S. Pat. No. 5,090,504, dated Feb. 25, 1992, to Amacker; U.S. Pat. No. 5,097,925 dated Mar. 24, 1992, to Walker; U.S. Pat. No. 5,279,390, dated Jan. 18, 1994, to Phillips; U.S. Pat. No. 5,311,967, dated May 17, 1994 to Kennedy; U.S. Pat. No. 5,332,063, dated Jul. 26, 1994, to Amacker; U.S. Pat. No. 5,590,738, dated Jan. 7, 1997, to Hunt, et al; U.S. Pat. No. 5,641,036, dated Jan. 24, 1997, to Maxwell; U.S. Pat. No. 5,642,789, dated Jul. 1, 1997, to Maxwell; and U.S. Pat. No. 5,775,464, dated Jul. 7, 1998, to Gardner. None of the devices disclosed in those patents includes a mechanism for automatically tightening a platform support cable around a tree having a given diameter. U.S. Pat. No. 5,226,505, dated Jul. 13, 1993, to Donald R. Woller, et al, details a “Portable Climbing Platform” characterized by a pair of pivoting arms provided on opposite sides of a frame, the front ends of which arms are spanned by a pair of tree-engaging blades adjustably joined to each other. The front ends of the arms can be displaced laterally or medially, and the blades adjusted with respect to each other, to accommodate a tree having a given diameter. U.S. Pat. No. 5,234,076, dated Aug. 10, 1993, to Robert L. Louk, details a “Tree Stand”, including a climbing platform for supporting a hunter on a tree and a foot platform for engaging the tree beneath the climbing platform. A folding support on each side of each frame can be pivoted between horizontal and vertical positions, and a flexible steel cable extends from one support around the tree and is removably fastened to the other support to secure the corresponding platform on the tree. The supports pivot on the platform to conform the loop width of the cable with a tree having a given diameter. 
     Many of the prior art climbing platforms, and portable climbing stands in particular, suffer from the disadvantages of being relatively complicated and sometimes heavy, which are severe disadvantages to a hunter, who must depend upon mobility in order to assure access to the areas frequented by wild game such as deer. Furthermore, some of the prior art devices, while light in weight, are not structurally sound and are insufficiently large for relative positioning of the hunter and many do not include sufficient safety features which are necessary for the average hunter. 
     Accordingly, it is an object of this invention to provide a new and improved tree climbing apparatus which is characterized by a high degree of safety, ease of manipulation and transportation and facilitates great comfort and multiple position capability for the user when in position on a tree or pole. 
     Another object of this invention is to provide a new and improved portable climbing platform which can be quickly and easily transported to a desired hunting area and removably attached and automatically adjusted to a tree or pole and a cooperating foot platform removably attached to the tree or pole beneath the climbing platform, wherein the user alternately stands on the foot platform and lifts and secures the climbing platform and then sits on the climbing platform to lift and secure the foot platform in order to work his or her way up and down the tree or pole. 
     Yet another object of this invention is to provide an efficient tree climbing apparatus having a climbing platform and cooperating foot platform, which climbing platform and foot platform are each characterized by a generally rectangular-shaped frame for supporting a hunter while the hunter ascends a tree or pole, a V-shaped blade or engaging bar provided on the frame for cooperative engagement with the tree, and a cable extending around the tree above the blade and through self-adjusting guide members to provide self-adjusting, safe and firm support of the climbing platform and foot platform on the tree. 
     Still another object of this invention is to provide a tree climbing platform having a pair of pivotally-mounted cable guide bars and a cooperating foot platform, which are each amenable to easy and efficient manipulation in order to facilitate repetitive adjustment in the attitude and height of the two platforms on a tree. 
     A further object of this invention is to provide a new and improved tree climbing platform and cooperating foot platform which are each characterized by a frame having a tree-engaging blade or bar provided on the front end of the frame for engaging a tree; a pivoting cable adjusting guide bar, the front end of which is slidably mounted for lateral and medial displacement on one side of the corresponding platform at the front end thereof; a pivoting cable retention guide bar, the front end of which is slidably mounted for lateral and medial displacement on the other side of the corresponding platform at the front end thereof; and a support cable or bicycle-type support chain having one end attached to a cable adjusting handle slidably and adjustably mounted on the cable adjusting guide bar. The other end of the cable or chain is extended around the tree and removably attached to the cable retention guide bar and the cable or chain is tightened by means of the cable-adjusting handle to support the user at a selected height on the tree as the tightening cable or chain slides the front ends of the pivoting cable adjusting and cable retention guide bars inwardly on the corresponding frame, to tighten the cable or chain around a tree having a given diameter. 
     Another object of this invention is to provide an adjustable tree climbing apparatus including a climbing platform and foot platform which cooperate to facilitate multiple selected sitting and standing positions for a user, both facing a tree or pole and facing away from the tree or pole, which foot support platform supports the user in the standing positions and which climbing platform supports the user in one of several sitting positions. 
     SUMMARY OF THE INVENTION 
     These and other objects of the invention are provided in a tree climbing apparatus including a climbing platform and cooperating foot platform, each of which includes a platform frame provided with a generally V-shaped tree-engaging bar or blade on the front end of the frame for engaging a tree. A cable adjusting guide bar is pivotally attached to the rear end of the corresponding frame on one side of each platform and a cable retention guide bar is pivotally attached to the rear end of the corresponding frame on the opposite side of each platform. The front ends of the cable adjusting and cable retention guide bars, respectively, are slidably mounted on the respective frames for lateral and medial displacement on opposite sides of the corresponding platform frame, at the front end thereof. One end of a support cable or bicycle type support chain is attached to a cable adjusting handle slidably and adjustably mounted on the cable adjusting guide bar on each platform and the other end of the cable or chain is extended around the tree and removably attached to the cable retention guide bar on the corresponding platform. The support cable or chain engages the opposite side of the tree above the blade or bar for supporting the climbing platform or foot platform at a selected height on the tree. As the cable or chain is tightened around the tree by operation of the handle, the front ends of the pivoting cable adjusting and cable retention guide bars slide inwardly on the platform according to the tree diameter to tighten the cable or chain around the sides of the tree. The climbing platform and foot platform are alternatively moved higher on the tree in “inchworm” fashion, until both are positioned at a selected height on the tree for hunting. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be better understood by reference to the accompanying drawings, wherein: 
     FIG. 1 is an exploded, perspective view of the climbing platform of a preferred embodiment of the tree climbing apparatus of this invention; 
     FIG. 2 is a top view of the climbing platform of another embodiment of the tree climbing apparatus, with the pivoting cable adjusting and cable retention guide bars positioned on the platform as if to tighten the support cable around a tree having a large diameter; 
     FIG. 3 is a top view of the climbing platform of the tree climbing apparatus illustrated in FIG. 2, with the pivoting cable adjusting and cable retention guide bars positioned on the platform as if to tighten the support cable around a tree having a small diameter; 
     FIG. 4 is an enlarged, sectional view of the cable retention guide bar on the climbing platform of the tree climbing apparatus, more particularly detailing attachment of the support cable component after extension around a tree, to a cable retention bolt prior to securing the cable retention bolt on the cable retention guide bar, in a preferred technique for securing the support cable to the cable retention guide bar; 
     FIG. 5 is an enlarged, sectional view of the cable retention guide bar illustrated in FIG. 4, more particularly detailing attachment of the cable retention bolt and attached support cable to the cable retention guide bar; 
     FIG. 6 is a perspective view, partially in section, of a cable adjusting handle element of a preferred embodiment of the tree climbing apparatus of this invention; 
     FIG. 7 is a top view of a typical foot platform of the tree climbing apparatus, with the pivoting cable adjusting and cable retention guide bars positioned on the platform as if to tighten the support cable around a tree having a large diameter; 
     FIG. 8 is a top view of the foot platform of the tree climbing apparatus illustrated in FIG. 7, with the pivoting cable adjusting and cable retention guide bars positioned on the platform as if to tighten the support cable around a tree having a small diameter; 
     FIG. 9 is a perspective view of a preferred embodiment of the tree climbing apparatus, illustrating the climbing platform and foot platform in initial climbing position on a tree at a selected height above the ground; 
     FIG. 10 is a perspective view of the tree climbing apparatus illustrated in FIG. 9, more particularly detailing raising the climbing platform to a selected, higher location on the tree; 
     FIG. 11 is a perspective view of the tree climbing apparatus illustrated in FIG. 9, more particularly detailing lifting the foot platform to a selected, higher location on the tree; 
     FIG. 12 is a perspective view of the tree climbing apparatus positioned at a selected height on the tree; 
     FIG. 13 is a side view detail, partially in section, of a cable retention handle element of a preferred embodiment of the tree climbing apparatus of this invention; and 
     FIG. 14 is a top view of the climbing platform of another embodiment of the tree-climbing apparatus of this invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring initially to FIGS. 1-9 of the drawings, in a preferred embodiment, the tree climbing apparatus of this invention is generally illustrated by reference numeral  1 . As illustrated in FIG. 9, the tree climbing apparatus  1  includes a climbing platform  23 , shown situated in engagement with a tree  46 , and a foot platform  2 , shown likewise situated in engagement with the tree  46 , below the climbing platform  23 . The climbing platform  23  is characterized by a generally rectangular climbing platform frame  24 , typically constructed of steel or, preferably, aluminum, square tubing. The climbing platform frame  24  includes a pair of spaced-apart, parallel seat support bars  27 , typically spanned by a rear brace bar  30  and a front brace bar  29 , as illustrated in FIG.  1 . Blade mount bars  31 , each having one end welded or otherwise fixedly or removably attached to the extending end of the corresponding seat support bar  27 , angle rearwardly and terminate adjacently on the front brace bar  29 , forming a generally V-shaped configuration. A tree-engaging blade  31   a  is mounted on each blade mount bar  31  and the front brace bar  29 , typically by means of a blade mount clamp  31   b , for receiving and engaging the tree  46 , as hereinafter further described. In a preferred embodiment of the tree climbing apparatus  1  illustrated in FIG. 1, a backrest  16 , characterized by a pair of spaced-apart backrest arms  18 , spanned by a typically fabric or flexible net backing  17 , is typically removably attached to the rear end of the climbing platform frame  24 . The bottom end of each backrest arm  18  is inserted between a corresponding pair of spaced-apart backrest attachment flanges  19 , provided on the rear brace bar  30 , adjacent to each end thereof. A bolt  20  is extended through a pair of aligned flange openings (not illustrated) provided in each pair of backrest attachment flanges  19  and a registering seat arm bolt opening  18   a , provided in the lower end of the corresponding, vertical backrest arm  18 , and a nut  14  is threaded on each bolt  20 , to removably secure the backrest  16  to the climbing platform frame  24 . 
     A cable retention guide bar  25  and a cable adjusting guide bar  26  are pivotally mounted at the rear end of each, to the rear brace bar  30  on each side of the climbing platform frame  24 , as hereinafter further described. A guide bar clevis  35  provided with a pair of spaced-apart clevis flanges  35   a , is extended through a corresponding guide bar clevis opening  35   b  located at each end of the rear brace bar  30 , as illustrated in FIG. 1, and secured therein by means of a flat washer  15  and a nut  14 , threaded on the guide bar clevis  35 . The rear ends of the cable retention guide bar  25  and the cable adjusting guide bar  26  are placed between the clevis flanges  35   a  of the corresponding, fastened guide bar clevis  35 . A bolt  20  is extended through aligned flange openings  35   c  provided in the respective clevis flanges  35   a  and through a registering guide bar bolt opening  21  provided in the rear end of the corresponding cable retention guide bar  25  and cable adjusting guide bar  26 . A nut  14  is threaded on the extended bolt  20  to secure the cable retention guide bar  25  and cable adjusting guide bar  26  between the clevis flanges  35   a  of the corresponding guide bar clevis  35 . The front end of each cable retention guide bar  25  and cable adjusting guide bar  26  bends perpendicularly inwardly at a bend  37  and the forward end of each cable retention guide bar  25  and cable adjusting guide bar  26  terminates on a corresponding, typically rectangular, guide bar connecting frame  33 . A frame connecting flange  36 , provided on the underside of the bottom frame member  33   a  of each guide bar connecting frame  33 , receives the blade mount bar  31  of the climbing platform frame  24 , on the corresponding side of the blade mount clamp  31   b . A bolt  20  is extended downwardly through a bolt opening  33   b  provided in the bottom frame member  33   a  of the guide bar connecting frame  33  and through a flange bolt opening  36   a  provided in the frame connecting flange  36 , which bolt  20  extends adjacent to the blade mount bar  31  and receives a nut  14  to secure each guide bar connecting frame  33  on the corresponding blade mount bar  31 . Accordingly, each guide bar connecting frame  33  is slidably mounted for lateral and medial displacement on the corresponding blade mount bar  31  and the cable retention guide bar  25  and cable adjusting guide bar  26  can be pivoted with the corresponding guide bar clevis  35 , between the laterally-disposed position illustrated in FIG.  2  and the medially-disposed position illustrated in FIG. 3, for purposes which will be hereinafter further described. As illustrated in FIGS. 1 and 6, a cable adjusting handle  38  is slidably and adjustably mounted on the cable adjusting guide bar  26  and includes an adjusting lever  39  (FIG.  6 ), which is pivotally mounted on a fulcrum  42 , provided on the underside of the cable adjusting handle  38 , as illustrated in FIG. 1, or alternatively, on the side of the cable adjusting handle  38 , as illustrated in FIGS. 2 and 3. One end of the adjusting lever  39  is biased away from the cable adjusting guide bar  26  by means of a spring  40 . A handle retention pin  41 , extending from the other end of the lever  39 , is normally inserted in one of a selected number of pin openings  26   a , provided at spaced intervals in the bottom surface (FIG. 1) or side surface (FIGS. 2 and 3) of the cable adjusting guide bar  26 , to secure the cable adjusting handle  38  at a selected location along the cable adjusting guide bar  26 , as hereinafter further described. As further illustrated in FIG. 1, a support cable  32  extends from typically bolted attachment at one end to a retention flange  49  provided on the underside of the cable adjusting handle  38 , beneath the cable adjusting guide bar  26  and the other end of the support cable  32  extends through a cable guide loop  44  provided on a threaded cable guide bolt  44   a , secured in a guide bolt opening  44   b  provided in the cable adjusting guide bar  26 , near the front end thereof, by means of a threaded nut  14 . As illustrated in FIG. 1, the support cable  32  is extended through a cable guide  34  provided on each guide bar connecting frame  33  and is removably attached to the cable retention guide bar  25 , as hereinafter described. 
     In another embodiment of the tree-climbing apparatus  1  illustrated in FIG. 14, the support cable  32  of the climbing platform  23  is replaced by a bicycle-type support chain  43 , which extends from fixed attachment at one end to the cable adjusting handle  38  and through the cable guide loop  44 , provided on the cable adjusting guide bar  26 . The support chain  43 , like the support cable  32  of the climbing platform  23  described above and illustrated in FIGS. 1 and 2, is extended through the cable guide  34  provided on each guide bar connecting frame  33 , and removably attached to the cable retention guide bar  25 , as hereinafter described. As illustrated in FIGS. 1-3, a safety clip  45  is optionally attached by means of a safety clip cable  45   a , to the climbing platform frame  24  to facilitate tethering the foot platform  2  to the tree-mounted climbing platform frame  24  and prevent the foot platform  2  from inadvertently dropping from the climbing platform  23 , to the ground. 
     In application, as hereinafter further described, the tree-engaging blades  31   a  are initially caused to engage the tree  46 , the support cable  32  or support chain  43  (FIG. 14) is extended through the cable guide  34  provided on the guide bar connecting frame  33  of the cable adjusting guide bar  26 , around the tree  46  and through the cable guide  34  provided on the guide bar connecting frame  33  of the cable retention guide bar  25 . A retention tab  50 , provided on the extending end of the support cable  32  or support chain  43 , is inserted on a cable retention bolt  13  fitted with a bolt keeper  13   a , as illustrated in FIG.  4 . The cable retention bolt  13  is then extended through a selected one of multiple, spaced retention openings  25   a  provided in the cable retention guide bar  25 , which retention openings  25   a  are selected according to the desired tension of the support cable  32  around the thickness or girth of the tree  46 . The bolt keeper  13   a  is then re-positioned on the cable retention bolt  13 , to prevent the retention tab  50  from slipping off the cable retention bolt  13  and secure the support cable  32  or support chain  43  to the cable retention guide bar  25 , as illustrated in FIG.  5 . It is understood that because the support cable  32  extends through the respective cable guide loops  44 , connected to the cable retention guide bar  25  and cable adjusting guide bar  26 , pressure on the support cable  32  forces the cable retention guide bar  25  and the cable adjusting guide bar  26  inwardly against the tree to create a naturally-occurring pinching effect. This pinching effect is generated by the cable configuration, which creates the clamping effect and stabilizes the tree climbing apparatus on the tree  46 . Furthermore, the bends  37  in the respective cable retention guide bar  25  and the cable adjusting guide bar  26  create additional space for the hunter when the hunter is sitting in the seats  28  with his back to the tree  46 . 
     Referring now to FIGS. 1-3 of the drawings, one or a pair of seats  28 , typically constructed from a durable fabric or flexible net, spans the seat support bars  27  of the climbing platform frame  24 . As illustrated in FIGS. 2 and 3, when two seats  28  span the seat support bars  27 , one of the seats  28  is typically located adjacent to the front brace bar  29  and the other adjacent to the rear brace bar  30 , of the climbing platform frame  24 , upon which seats  28  the hunter sits when the climbing platform  23  is supported on the tree  46 . It will be appreciated that the hunter may sit on the climbing platform  23  facing either of two directions. By sitting on the rear seat  28 , the hunter faces the tree  46  and by sitting on the front seat  28 , the hunter faces away from the tree  46 . 
     Referring again to FIGS. 4-9 of the drawings, the foot platform  2  of the tree climbing apparatus  1  is characterized by a foot platform frame  3 , generally constructed in the same manner as the climbing platform frame  24 , typically from steel or aluminum tubing. The foot platform frame  3  includes a rectangular mesh frame  5 , characterized by a pair of spaced-apart, parallel mesh frame side members  12  spanned by a front frame member  12   a  and a rear frame member  12   b . The front frame member  12   a  and rear frame member  12   b  are spanned by a pair of parallel mesh frame braces  5   a  and a rigid, expanded metal foot support mesh  4  is typically welded on the mesh frame  5  and supported by the mesh frame braces  5   a . Blade mount bars  9  angle rearwardly from the extending front ends of the respective mesh frame side members  12  of the mesh frame  5 , terminating adjacently on the front end of the front mesh frame member  12   a  and forming a substantially V-shaped configuration. A pair of tree-engaging blades  9   a  is mounted on the respective blade mount bars  9 , typically by means of a blade mount clamp  9   c , for receiving and engaging the tree  46  beneath the climbing platform  23 , as illustrated in FIG.  9 . The rear ends of a cable retention guide bar  6  and a cable adjusting guide bar  7 , respectively, are pivotally attached typically by means of bolts  20 , as illustrated in FIGS. 7 and 8, to the respective mesh frame side members  12  of the mesh frame  5 , adjacent to the rear frame member  12   b . The front ends of the cable retention guide bar  6  and cable adjusting guide bar  7  extend downwardly as a vertical front retention guide support  6   a  and front adjusting guide support  7   a , respectively, as illustrated in FIG. 9. A support extension  9   b  extends rearwardly from the bottom end of the front retention guide support  6   a  and front adjusting guide support  7   a , respectively, and each terminates in a connecting bar  8 , each of the latter provided with a bottom connecting flange (not illustrated) and a top connecting flange  8   a , as illustrated in FIGS. 7 and 8. As further illustrated in FIG. 7, a bolt  20  is extended downwardly through aligned bolt openings (not illustrated) provided in the top connecting flange  8   a  and bottom connecting flange (not illustrated) of each pair, adjacent to the blade mount bar  9 , and receives a nut (not illustrated) to slidably secure each connecting bar  8  on the blade mount bar  9  on the corresponding side of the blade mount clamp  9   c . Accordingly, the cable retention guide bar  6  and cable adjusting guide bar  7  are slidably mounted for lateral and medial displacement on the respective blade mount bars  9  and can be pivoted between the laterally-disposed position illustrated in FIG.  7  and the medially-disposed position illustrated in FIG. 8, for purposes which will be hereinafter further described. A pair of foot straps  51  is typically provided on the foot support mesh  4  for receiving the feet of the hunter to facilitate lifting the foot platform  2  on the tree  46 , as illustrated in FIG.  11  and hereinafter further described. 
     A cable adjusting handle  38  is slidably and adjustably mounted on the cable adjusting guide bar  7  and, like the cable adjusting handle  38  on the cable adjusting guide bar  26  of the climbing platform  23 , includes an adjusting lever  39  (illustrated in FIG.  6 ), pivotally mounted on a fulcrum  42 , provided on the side or bottom surface of the cable adjusting handle  38 , as illustrated in FIG. 6 with respect to the cable adjusting handle  38  described above with respect to the climbing platform  23 . Accordingly, one end of the adjusting lever  39  is biased away from the cable adjusting guide bar  7  by means of a spring  40  (FIG. 6) and the opposite end of the adjusting lever  39  includes a handle retention pin  41 , normally inserted in a selected one of multiple pin openings  26   a , provided at spaced intervals on the side or bottom surface of the cable adjusting guide bar  7 , as described above with respect to the cable adjusting guide bar  26  of the climbing platform  23  illustrated in FIG.  6 . One end of a support cable  11  is typically bolted to the bottom surface of the cable adjusting handle  38 . As illustrated in FIGS. 7 and 8, the other end of the support cable  11  extends forwardly through a cable guide loop  44  provided near the front end of the cable adjusting guide bar  7 , as described above and illustrated in FIG. 1 with respect to the climbing platform  23  and through a second cable guide loop  44  provided near the front end of the cable retention guide bar  6 . The extending end of the support cable  11  terminates in a retention tab  50 , which is inserted on a cable retention bolt  13  (as illustrated in FIG.  4  and described above with respect to the climbing platform  23 ), removably inserted and secured in a selected retention opening  25   a  provided in the cable retention guide bar  6 . 
     As described above with respect to the climbing platform  23  illustrated in FIG. 14, in another embodiment of the tree climbing apparatus  1 , the support cable  11  of the foot platform  2  is replaced by a bicycle-type support chain (not illustrated) having one end typically bolted to the cable adjusting handle  38 . The other end of the support chain (not illustrated) extends forwardly through the cable guide loop  44  provided on the cable adjusting guide bar  7  and through the second cable guide loop  44  provided on the cable retention guide bar  6 , in the same manner as the support cable  32  of the climbing platform  23  described above and illustrated in FIGS. 7 and 8. The extending end of the support chain (not illustrated) terminates in a retention tab  50 , which is inserted on a cable retention bolt  13 , removably inserted and secured in a selected retention opening  25   a  provided in the cable retention guide bar  6 , as described above and illustrated in FIGS. 4 and 5. 
     In the course of mounting the foot platform  2  on the tree  46 , the tree-engaging blades  9   a  of the foot platform  2  are initially positioned to engage the tree  46 . The free end of the support cable  11  or support chain (not illustrated) is then extended around the tree  46  and through the cable guide loop  44  provided on the cable retention guide bar  6  and the retention tab  50  is inserted on the cable retention bolt  13 , as illustrated in FIG.  4 . The cable retention bolt  13  is then extended through a selected pair of retention openings  25   a  provided in the cable adjusting guide bar  7 , which pair of retention openings  25   a  is selected according to the thickness or girth of the tree  46 . The bolt keeper  13   a  is then replaced on the cable retention bolt  13 , as illustrated in FIG. 5, to retain the support cable  11  or support chain on the cable retention guide bar  6  as the foot support platform  2  is supported on the tree  46 . The climbing platform  23  is then secured to the tree  46  above the foot platform  2  in like manner, as hereinafter further described. 
     Referring again to FIGS. 4-6 and to FIGS. 10-12 of the drawings, in typical detailed mounting and climbing application, the foot support platform  2  is positioned on the tree  46  as described above. Accordingly, the tree-engaging blades  31   a  of the foot platform frame  3  are initially caused to engage the tree  46 . The support cable  11  or support chain (not illustrated) is then extended around the tree  46  and through the cable guide loop  44  provided on the cable retention guide bar  6 , and the retention tab  50  is inserted on the cable retention bolt  13  and secured as illustrated in FIGS. 4 and 5 and heretofore described. The support cable  11  or support chain is next tightened around the tree  46  by first pivoting the projecting end of the adjusting lever  39  of the cable adjusting handle  38  toward the cable adjusting guide bar  7 , thereby removing the handle retention pin  41  from the pin opening  26   a , and sliding the cable adjusting handle  38  rearwardly on the cable adjusting guide bar  7 , and then inserting the handle retention pin  41  in another pin opening  26   a , by releasing the spring-biased adjusting lever  39 . The tightening support cable  11  or support chain causes the cable retention guide bar  6  and cable adjusting guide bar  7  to pivot between the outwardly-disposed position illustrated in FIG.  7  and the inwardly-disposed position illustrated in FIG. 8, according to the girth of the tree  46 , such that the support cable  11  or support chain firmly engages the rear and side portions of the tree  46 . 
     Next, the climbing platform  23  is positioned on the tree above the foot platform  2 . Accordingly, after the free end of the support cable  32  or support chain  43  (FIG. 14) of the climbing platform  23  is extended through the cable guide  34  provided on the guide bar connecting frame  33  of the cable adjusting guide bar  26 , the tree-engaging blades  31   a  of the climbing platform frame  24  are caused to engage the tree  46  above the foot platform  2 . The support cable  32  or support chain  43  of the climbing platform  23  is extended around the tree  46  and through the cable guide  34  provided on the guide bar connecting frame  8  of the cable retention guide bar  25  and the retention tab  50  is inserted on the cable retention bolt  13  and secured as illustrated in FIGS. 4 and 5 and described above with respect to the foot platform  2 . The support cable  32  or support chain  43  is tightened around the tree  46  by adjusting the cable adjusting handle  38  rearwardly on the cable adjusting guide bar  26 , in the manner described above with respect to the foot platform  2 . The tightening support cable  32  or support chain  43  causes the cable retention guide bar  25  and cable adjusting guide bar  26  to pivot between the outwardly-disposed position illustrated in FIG.  2  and the inwardly-disposed position illustrated in FIG. 3, according to the girth of the tree  46 , such that the support cable  32  or support chain  43  always firmly engages the rear and side portions of the tree  46 . The climbing platform  23  is thusly supported in functional configuration on the tree  46  above the foot platform  2 , as illustrated in FIG.  9 . As illustrated in FIG. 10, the hunter then steps onto the mounted foot platform  2  and places his or her feet in the foot straps  51 , with his or her legs between the seat support bars  27  of the climbing platform frame  24  and he or she lifts the rear end of the mounted climbing platform  23  in the direction of the arrow. This tilting movement removes the support cable  32  or support chain  43  from tensioned engagement with the tree  46 , after which the tree-engaging bars  31  are removed from engagement with the tree  46  to facilitate positioning the climbing platform  23  and attached support cable  32  or support chain  43  at a higher position on the tree  46 , as illustrated in FIG.  11 . This is effected by lifting the climbing platform  23  and then lowering the rear end of the climbing platform  23  at the selected higher location on the tree  46 , thereby causing the tree-engaging bars  31  and support cable  32  on support chain  43  to again securely engage the tree  46 . The hunter then sits on the seat  28  of the secured climbing platform  23 , places his or her feet beneath the foot strap  51  on the foot platform frame  3  and raises his or her feet as he or she sits on the seat  28 , to tilt the foot platform  2  forwardly and remove the support cable  11  or support chain (not illustrated) from engagement with the tree  46 . The tree-engaging blades  9   a  are also removed from engagement with the tree  46  to facilitate lifting the foot platform  2  in the direction of the arrow to a higher position on the tree  46 . The rear end of the foot platform  2  is lowered as weight is re-applied to the foot platform  2  to secure the foot platform  2  on the tree  46  at the higher level. By repeating the climbing technique described above, the hunter alternately raises the climbing platform  23  and foot support platform  2  in “inchworm” fashion to a selected height on the tree  46  for hunting deer or other game. As the diameter of the tree  46  becomes smaller upon ascending the tree  46 , the cable adjusting guide bars  26  and  7  and cable retention guide bars  25  and  6  pivot inwardly on the respective climbing platform  23  and foot platform  2 , as illustrated in FIGS. 3 and 8, respectively, such that the support cables  32  and  11 , respectively, or support chain  43  on the climbing platform  23  and support chain (not illustrated) provided on the foot platform  2 , respectively, tighten against the rear and sides of the tree  46 . This causes the climbing platform  23  and foot platform  2  to assume an upwardly-sloped position on the tree  46 , with the rear end of the corresponding platform located at a lower level than the front, tree-engaging end of the platform. Accordingly, the cable adjusting handles  38  on both the climbing platform  23  and the foot platform  2  are manipulated to slide rearwardly on the respective cable adjusting guide bars  26  and  7 , and maintain the climbing platform  23  and foot platform  2  at a level position on the tree  46  and yet insure a tight fit of the support cables  32  and  11 , respectively, or support chain  43 , on the climbing platform  23  and support chain on the foot platform  2 , around the rear and sides of the tree  46 . The hunter descends the tree  46  by reversing the climbing process described above, alternately lowering the climbing platform  23  and foot support platform  2  until he or she reaches the ground. As the diameter of the tree  46  becomes larger upon descending the tree  46 , the cable adjusting guide bars  26  and  7  and cable retention guide bars  25  and  6  pivot outwardly on the respective climbing platform  23  and foot platform  2 , as illustrated in FIGS. 2 and 7, respectively, to conform the loop width of the support cables  32  and  11 , respectively, or support chain  43  on the climbing platform  23  and support chain on the foot platform  2 , respectively, to the increasing tree diameter. This causes the climbing platform  23  and foot platform  2  to assume a downwardly-sloped position on the tree  46 , with the rear end of the corresponding platform located at a higher level than the front, tree-engaging end of the platform. Accordingly, the cable adjusting handles  38  on both the climbing platform  23  and the foot platform  2  are manipulated to slide forwardly on the respective cable adjusting guide bars  26  and  7  to maintain the climbing platform  23  and foot platform  2  at a level position on the tree  46  and yet maintain a tight fit of the support cables  32  and  11 , respectively, or support chain  43  on the climbing platform  23  and support chain on the foot platform  2 , respectively, around the rear and sides of the tree  46 . 
     Referring next to FIGS. 13 and 14 of the drawings, in another preferred embodiment of the invention the extending end of the support cable  32  or support chain  43  of the climbing platform  23  is removably attached to a cable retention handle  48 , slidably mounted on the cable retention guide bar  25  of the climbing platform  23 , opposite the cable adjusting handle  38  on the cable adjusting guide bar  26 , for enhancing the adjusting capability of the support cable  32  or support chain  43  around the tree  46 . The cable retention handle  48  includes an adjusting lever  48   a , which is pivotally mounted on a fulcrum  48   b , provided on the bottom surface of the cable retention handle  48 , and one end of the adjusting lever  48   a  is biased downwardly by means of a spring  48   d . A locking peg  48   c  extends upwardly from the other end of the lever  48   a  and inserts in one of at least three pairs of retention openings  25   a  provided at spaced intervals in the bottom surface of the cable retention guide bar  25 . A pair of spaced-apart retention flanges  49  extends downwardly from the front end of the cable retention handle  48  on each side thereof and a pair of aligned flange openings  49   a  is included in the retention flanges  49 . The extending end of the support cable  32  or support chain  43  terminates by a weld in a retention tab  50 . After extension around the tree  46 , the retention tab  50  is inserted through a cable guide loop (not illustrated), provided on the end of the cable retention guide bar  25  and then positioned between the retention flanges  49 , where a tab opening  50   a , provided in the retention tab  50 , is aligned with the retention flange openings  49   a . A lock pin  47  is then extended through the flange openings  49   a  and aligned tab opening  50   a  to retain the retention tab  50  between the retention flanges  49 . Sliding the cable retention handle  48  forwardly or rearwardly on the cable retention guide bar  25  and inserting the locking peg  48   c  in one of the retention openings  25   a  enhances the user&#39;s ability to tighten and loosen the support cable  32  or support chain  43  around the tree  46  when the cable retention handle  48  is used in combination with the cable adjusting handle  38  provided on the cable adjusting guide bar  26  and enables the user to adjust the climbing platform  23  to a level position on any tree  46  and particularly, a tree having a large variation in diameter from the base to top. It will be appreciated that in this embodiment, a cable retention handle  48  may be likewise provided on the cable retention guide bar  6  of the foot platform frame  3 , for providing the same benefits in adjusting the support cable  11  or support chain (not illustrated) around the tree  46  during raising and lowering the foot platform  2  on the tree  46 . 
     While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications may be made in the invention and the appended claims are intended to cover all such modifications which may fall within the scope and spirit of the invention.