Abstract:
A treadbase supporting structure used in a treadmill and coupled between the framework and treadbase of the treadmill is constructed to include a first support member and a second support member, the first support member being retractable, the second support member being turnable relative to the first support member between a first position where the first support member and said second support member are axially aligned to support the treadbase in the non-operative position, and a second position where the first support member and said second support member are folded up and the treadbase is lowered to the operative position.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates generally to treadmills, and more particularly to a treadbase supporting structure for treadmill.  
           [0003]    2. Description of the Related Art  
           [0004]    A conventional treadmill, as shown in FIG. 1, is generally composed of a treadbase  1 , a base frame  2 , and a support  3  connected between the base frame  2  and the treadbase  1  for supporting the treadbase  1  to be mounted fixedly on the base frame  2  in a non-operative position. The support  3  includes an outer tube  3   a , an inner tube  3   b  fitted in the outer tube  3   a , a tensile spring (not shown) mounted inside the outer tube  3   a , and a tightening screw  4  mounted outside the outer tube  3   a . When the treadbase  1  is turned from an operative position to the non-operative position, the tightening screw  4  is screwed inwards and contacts against the periphery of the inner tube  3   b  to stop the inner tube  3   b  from further moving inside the outer tube  3   a . however, the tightening force of the tightening screw  4  is weak such that the inner tube  3   b  is subject to fall inside of the outer tube  3   a  and the treadmill is structurally defective. Furthermore, while changing the position of the treadbase  1 , a user must hold the treadbase  1  with one hand, and then screw up or loosen the tightening screw  4  with the other hand, i.e. the user fails to adjust the treadbase  1  between the operative position and the non-operative position with one single hand.  
           [0005]    [0005]FIGS. 2 and 3 show another treadmill folding structure according to the prior art. According to this design, a retractable support connecting between the base frame  8  and the treadbase  5  is composed of a stop member  6  and a retractable rod  7 . The retractable rod  7  is composed of a tubular outer rod member  7   a  and a piston  7   b . The tubular outer rod member  7   a  has a first end pivoted to the treadbase  5 , and a second end having a stop flange  7   c . The stop member  6  is a hollow cylindrical member having a notched stop edge  6   a  in a top end thereof. The piston  7   b  has an end connected to the inside of the stop member  6 , and the other end inserted in the tubular outer rod member  7   a . When the treadbase  5  is set in the non-operative position, the stop flange  7   c  is stopped at the notched stop edge  6   a  (see FIG. 3A), and therefore the treadbase  5  is supported in the non-operative position (see FIG. 2). When changing the treadbase  5  from the non-operative position to the operative position, disengage the stop flange  7   c  from the notched stop edge  6   a  to keep the tubular outer rod member  7   a  in alignment with the piston  7   b  coaxially (see FIG. 3B), and then the treadbase  5  is lowered. However, treadmill is structurally defective. When a child touched the stop member  6  accidentally, the notched stop edge  6   a  may be forced away from the stop flange  7   c , thereby causing the treadbase  5  to fall.  
         SUMMARY OF THE INVENTION  
         [0006]    It is the primary objective of the present invention to provide a treadbase supporting structure, which firmly and safely supports the treadbase of a treadmill in a non-operative position.  
           [0007]    It is the secondary objective of the present invention to provide a treadbase supporting structure for a treadmill, which can be easily changed between an operative position and the non-operative position.  
           [0008]    To achieve the foregoing objectives of the present invention, the treadmill is composed of a framework, a treadbase, and at lease one treadbase supporting structure. The treadbase is pivotally connected with the framework at a front end thereof so as to be turned relative to the framework between an operative position and a non-operative position and to be supported by the treadbase supporting structure in the non-operative position. The treadbase supporting structure includes a first locating plate fixedly located on the framework, a second locating plate fixedly located on the treadbase, and a support coupled between the first locating plate and the second locating plate. The support includes a first support member and a second support member. The first support member has a first end connected pivotally with the first locating plate, a second end, and a pivot at the second end. The second support member has a first end connected pivotally with the pivot of the first support member and a second end connected pivotally with the second locating plate. The second support member is turnable about the pivot between a first position where the first support member and the second support member are axially aligned to support the treadbase in the non-operative position, and a second position where the first support member and the second support member are folded up. One of the first and second support members is retractable. The retractable support member is received when the first support member and the second support member are folded up. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    [0009]FIG. 1 is a perspective view of a treadmill constructed according to the prior art;  
         [0010]    [0010]FIG. 2 is a perspective view of another treadmill according to the prior art;  
         [0011]    [0011]FIG. 3A is a sectional view in an enlarged scale of a retractable support of the conventional treadmill shown in FIG. 2;  
         [0012]    [0012]FIG. 3B is similar to FIG. 3A but showing a stop flange of a tubular outer rod member disengaged from a notched stop edge of a stop member;  
         [0013]    [0013]FIG. 4 is s a perspective view of a treadmill constructed according to a first preferred embodiment of the present invention;  
         [0014]    [0014]FIG. 5 is an exploded view of a treadbase supporting structure according to the first preferred embodiment of the present invention;  
         [0015]    FIGS.  6 (A) &amp;  6 (B) are partial schematic views of the treadbase supporting structure according to the first preferred embodiment of the present invention;  
         [0016]    [0016]FIG. 7 is similar to FIG. 4 but showing that the treadbase slightly is pushed forwards;  
         [0017]    FIGS.  8 (A) &amp;  8 (B) are similar to FIGS.  6 (A) &amp;  6 (B) but showing that the stop pin disengaged from the stop edges of the stop plates;  
         [0018]    [0018]FIG. 9 is similar to FIG. 4 but showing that a force is applied to an actuating member;  
         [0019]    [0019]FIG. 10 is similar to FIG. 9 but showing that a second support member is turned about a pivot bolt relative to a first support member;  
         [0020]    [0020]FIG. 11 is similar to FIG. 4 but showing that the treadbase is turned downwards;  
         [0021]    [0021]FIG. 12 is a perspective view of the treadmill constructed according to a second preferred embodiment of the present invention; and  
         [0022]    [0022]FIG. 13 is a partial exploded view of the support in accordance with the second preferred embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0023]    Referring to FIGS. 4 and 5, a treadmill  100  of a first preferred embodiment of the present invention is composed of a framework  10 , a treadbase  20 , a retractable support  30 , an actuating member  40 , and a return member  50 .  
         [0024]    The framework  10  includes a base frame  11  and a handrail  12 . The treadbase  20  is composed of treadbase frame  21 , and an endless belt  22 . The treadbase frame  21  is connected pivotally with the base frame  11  such that the treadbase  20  can be turned relatively to the base frame  11  between a horizontal operative position (not shown) and a tilted non-operative position (see FIG. 4). When set in the non-operative position, the contained angle between the treadbase  20  and the base frame  11  is less than 90°. Because the framework  10  and the treadbase  20  are similar to conventional designs, no further description in this regard is necessary.  
         [0025]    The base frame  11  has a rear transverse bar  111  and a first locating plate  112  fixedly mounted on the rear transverse bar  111  thereof. The treadbase frame  21  has a second locating plate  211  corresponding to the first locating plate  112 .  
         [0026]    The retractable support  30  includes a first support member  31 , a second support member  32 , and a pivot bolt  33 . Referring to FIGS.  6 (A) &amp;  6 (B). The first support member  31  has an end, namely, a bottom end connected pivotally with the first locating plate  112  at the base frame  11 , and the other end, namely, a top end fixedly provided with two parallel stop plates  311 . The stop plates  311  define a stop face  313 , and each stop plate  311  has a hook-like stop edge  312 . The first support member  31  can be turned about a pivoted point at the first locating plate  112  between a first position P 1  (see FIG. 4) and a second position P 2  (see FIG. 11). The second support member  32  is a retractable rod formed of an air cylinder  321  and a piston  322  moved in and out of the air cylinder  321 . A distal end of the piston  322  is pivotally connected to the second locating plate  211 . The air cylinder  321  has a mounting endpiece  323 , a longitudinal sliding slot  324  running through the mounting endpiece  323 , and a stop pin  325  positioned above the sliding slot  324  and protruding outwardly. The sliding slot  324  has a top end  324   a  and a bottom end  324   b . The pivot bolt  33  is inserted between the two stop plates  311  and is running through the sliding slot  324  of the mounting endpiece  323  of the air cylinder  321  such that the first support member  31  is pivotally connected with the second support member  32 .  
         [0027]    The actuating member  40  is a footplate fixedly mounted to a side of the first support member  31  and positioned above the first support member  31 .  
         [0028]    The return member  50  is a torsional spring mounted on the rear transverse bar  111  of the base frame  11  outside the first locating plate  112 , having an end extending to and stopped against a rear side of the first support member  31  for providing a rebounding force to drive the first support member  31  to turn toward the aforesaid first position P 1 .  
         [0029]    The operation of the present invention is described hereinafter. FIG. 4 shows that the treadbase  20  is supported by the retractable support  30  in the non-operative position. Meanwhile, the first support member  31  is in the first position P 1 , the first support member  31  and the second support member  32  are connected in alignment, and the compressed air inside the air cylinder  321  pushes the piston  322  in an extended position. As illustrated in FIGS.  6 (A) and  6 (B), the pivot bolt  33  is stopped at the top end  324   a  of the sliding slot  324 , the mounting endpiece  323  of the air cylinder  321  is supported on the stop face  313 , and the stop pin  325  is stopped at the stop edges  312  of the stop plates  311 . Therefore, the first support member  31  and the second support member  32  are connected in an axially aligned position to support the treadbase  20  in the non-operative position firmly.  
         [0030]    While lowering the treadbase  20  to the operative position, give a forward push force F 1  to a rear side of the treadbase  20  (see FIG. 7) to turn the treadbase  20  slightly forwards. At this time, the second support member  32  is moved outwards relative to the first support member  31 . As shown in FIGS.  8 (A) and  8 (B), the pivot bolt  33  is stopped at the bottom end  324   b  of the sliding slot  324 , and the stop pin  325  is disengaged from the stop edges  312  of the stop plates  311 .  
         [0031]    Next, tread the foot on the actuating member  40  to generate a force F 2  (See FIG. 9) on the actuating member  40 , and to further turn the second support member  32  about the pivot bolt  33  (see FIG. 10), thereby lowering the treadbase  20  slowly. When lowering the treadbase  20 , the first support member  31  is moved to the second position P 2  at first (see FIG. 11), and then the second support member  32  is turned about the pivot bolt  33 . Meanwhile the piston  322  is gradually pushed inside the air cylinder  321  until the treadbase  20  has been lowered to the operative position. When the treadbase  20  is lowered to the operative position, the first support member  31  and the second support member  32  are folded up (not shown).  
         [0032]    While retracting the treadbase  20 , lift the rear end of the treadbase  20  to pull the piston  322  out of the air cylinder  321 . At this time, the return member  50  drives the first support member  31  to move backwards toward the first position P 1 . When the treadbase  20  is turned to the non-operative position, the pivot bolt  33  is stopped at the top end  324   a  of the sliding slot  324 , the mounting endpiece  323  of the air cylinder  321  is supported on the stop face  313 , and the stop pin  325  is stopped at the stop edges  312  of the stop plates  311 . Thus, the first support member  31  and the second support member  32  are locked in the axially alignment to support the treadbase  20  in the non-operative position firmly.  
         [0033]    [0033]FIGS. 12 and 13 show a treadmill  200  constructed according to a second embodiment of the present invention. According to this embodiment, the treadmill  200  is composed of a base frame  201 , a treadbase  202 , two supports  60 , an actuating member  70 , and two return members  80 .  
         [0034]    The supports  60  are bilaterally coupled between the base frame  201  and the treadbase  202 , each composed of a first support member  61 , a second support member  62 , a tensile spring  63 , and a pivot bolt  64 . The first support member  61  is composed of an outer tube  611  and a retractable inner rod  612  coupled with the outer tube  611 . The outer tube  611  has an end connected pivotally with the base frame  201 . The retractable inner rod  612  is axially slidably mounted in the outer tube  611 , having two parallel stop plates  613  mounted and protruding at an end outside the outer tube  611 . The tensile spring  63  is connected between the outer tube  611  and one stop plate  613  of the retractable inner rod  612  to exert an inward force on the retractable inner rod  612  toward inside of the outer tube  611 . The second support member  62  has a longitudinal sliding slot  621  at an end, namely, the bottom end. The other end, namely, the top end of the second support member  62  is connected pivotally with the treadbase  202 . The pivot bolt  64  is inserted between the stop plates  613  and is running through the sliding slot  621  of the second support member  62  such that the second support member  62  is connected pivotally with the first support member  61 . Similar to the aforesaid first embodiment, the sliding slot  621  has a top end and a bottom end that work in the same manner as the sliding slot  324  of the aforesaid first embodiment.  
         [0035]    The actuating member  70  is composed of two links  71  and a footplate  72 . The links  71  are fixedly connected to the outer tubes  611  at two ends. The footplate  72  is fixedly mounted to the middle section of the links  71 .  
         [0036]    The two return members  80  are torsional springs mounted in the base frame  201  and respectively stopped against the outer tubes  611  of the first support members  61  of the two supports  60  to exert an upward force on the first support members  611 .