Abstract:
A multi-position adjustable height seat post comprises an inner tube, an outer tube, a locking assembly, a triggering device, a first extending element, and a second extending element disposed between the tubes. The locking assembly comprises an actuating unit, a plurality of parallel grooves located in the outer tube, a plurality of spherical detent elements located, in the grooves, and a plurality of spherical elements located in the inner tube. The triggering device connects to the actuating unit. The first extending element constantly pushes the to actuating unit moving in a first direction. The second extending element disposes between the tubes. Once the triggering device is triggered, the actuating unit moves in a second direction contrary to the first direction and makes the spherical elements to move inward laterally to let the inner tube and outer tube move relative to each other freely.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The invention relates to a multi-position adjustable height seat post, specifically a tube within another tube that allows for the adjustment of seat height to multiple positions while riding a bicycle. 
         [0003]    2. Description of Related Art 
         [0004]    Cyclists, specifically those involved in mountain hiking, find that it is beneficial to have a variety of seat height options while riding a bicycle. Seat height options are desired because they afford the rider greater control of the bicycle over widely varying terrain. 
         [0005]    U.S. Pat. No. 8,079,772 patent had disclosed a multi-position bicycle seat post locking assembly. This invention provides for a multi-position adjustable height bicycle seat post locking assembly comprising an inner tube slidably supported within an outer tube. The outer tube has a smaller diameter so as to be received in the seat tube of a bicycle. The inner tube is adjustable, moving freely within the outer tube when not in a locked position. The direction of movement is based upon rider input. Either downward via rider weight or upward via spring force. The outer tube accommodates a locking assembly consisting of ball bearings, a lock ring, a compression lever, a spring, and an upper and lower retaining unit. The locking mechanism works by forcing ball bearings via the lock ring into corresponding spherical detent elements on the inner tube through holes in the outer tube. The inner tube can have multiple positions of height adjustability depending on the number of spherical detent elements provided in the inner tube. The lock, ring is cut with a steep angle at its top portion transitioning to a shallower angle below the steep angle. In the locked, position the lock ring is forced upwards onto its shallow angle via spring force which holds the ball bearings in the corresponding spherical detent elements within the inner tube. This shallow angle along with constant spring force on the lock ring allows the locking mechanism to self adjust to along the shallow angle of the lock ring as the seat post wears into its working position. Unlocking the mechanism consists of forcing the lock ring off its shallow angle position, past its steep angled position, and onto an upper zero angled position. This allows the ball hearings clearance to exit the spherical detent elements of the inner tube so that the inner tube moves freely within the outer tube. 
         [0006]    Secondarily, the ball bearings are used to keep the inner post from twisting side to side as it travels longitudinally from position to position. This is done by forcing the ball bearings to track within channels of the inner tube. The channels run vertically from pocket to pocket along the inner tube. The inner tube is under constant force from a spring contained within the outer tube acting to extend the inner tube to its most extended position. 
         [0007]    But this kind of seat post has some drawbacks below: First, after using certain period of time, the appearance of the inner tube will be wearing in virtue of the wear happened between the inner tube and the ball bearings when riders are adjusting the height of the seat post. This will result in quick ageing of the product appearance. Second, the progress of manufacture is difficult in virtue of the process of components. 
         [0008]    The present invention has arisen to mitigate and/or obviate the disadvantages of the conventional. 
       SUMMARY OF THE INVENTION 
       [0009]    The purpose of the present invention is to provide a multi-position adjustable height bicycle seat post locking assembly that can overcome the aforesaid drawbacks. 
         [0010]    According to the present invention, the above purpose is achieved by a multi-position adjustable height bicycle scat post locking assembly mounted on the frame of a bike and essentially comprising an inner tube, an outer tube, a locking assembly, a triggering device, a first extending element, and a second extending element disposed between the tubes. The inner tube is adjustable, moving freely within the outer tube when not in a locked position. The direction of movement is based upon rider input. Either downward via rider&#39;s weight or upward via air pressure. The locking assembly is for locking, unlocking and preventing rotation of the inner tube with respect to the outer tube. The locking assembly comprises an actuating unit, a plurality of parallel grooves located in the outer tube, a plurality of spherical detent elements located in the parallel grooves, and a plurality of spherical elements located in the inner tube between the actuating unit and the outer tube. Furthermore, the above purpose is also achieved by a multi-position adjustable height bicycle seat post locking assembly with basically the same features mentioned above, wherein the outer tube consists of two separate pieces, and the hardness of the inter piece is higher than 200 Vickers Pyramid Number. 
         [0011]    When the multi-position adjustable height seat post is at the locked position, the spherical elements engage with the spherical detent elements respectively, and the inner tube cannot move relative to the outer tube. When the seat post is at the locked position and the triggering device is triggered, the seat post will enter into a free position. When the multi-position adjustable height seat post is at the free position after the actuation, the spherical elements move inward out of the spherical detent elements and can now slide in the grooves. This allows the inner tube to move respect to the outer tube in the longitudinal direction. If the rider weights the saddle, the inner tube will lower decreasing the volume of the inner space of the tubes and increasing the inside air pressure. When the triggering device is released, the actuating unit moves downward, and the spherical. elements will engage with the lower spherical detent elements once the inner tube has lowered to the corresponding height. 
         [0012]    The multi-position adjustable height seat post has several obvious advantages below: First, the internal locking mechanism improves external appearance of the inner tube. It hides wear damage of the interface inside on the outer tube for a like new external appearance in comparison with the U.S. Pat. No. 8,079,772 patent. Second, the smooth circular inner tube provides a proper sealing surface for wiper seal preventing dirt, water, and other contaminants from entering inside mechanism. Third, it allows for weight reduction in virtue of the replacing of coil spring with air spring. Fourth, the wear resistance is better in virtue of the steel material of the inner sleeve of outer tube. Fifth, it&#39;s easier to fabricate in virtue of the outer tube consisting of two separate pieces. The manufacturer can machine the inner piece and the outer piece individually. 
         [0013]    Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  shows a perspective view of the first embodiment of the present invention; 
           [0015]      FIG. 2  shows a another perspective view of the first embodiment of the present invention; 
           [0016]      FIG. 3  shows a sectional view of the first embodiment of the present invention in  FIG. 1 ; 
           [0017]      FIG. 4  shows a closer sectional view of FIG  3 ; 
           [0018]      FIG. 5  shows a sectional view of  FIG. 2  in a different direction; 
           [0019]      FIG. 6  shows a closer sectional view of  FIG. 5 ; 
           [0020]      FIG. 7  shows a top view of the outer tube and spherical elements of the first embodiment; 
           [0021]      FIG. 8  shows a sectional view of an outer tube, wherein the detent elements are spherical; 
           [0022]      FIG. 9  shows a sectional view of a different kind of outer tube, wherein the detent elements are cylindrical; 
           [0023]      FIG. 10  shows a sectional view of a different kind of outer tube, wherein the detent elements are annular; 
           [0024]      FIG. 11  shows another sectional view of  FIG. 2 , wherein a triggering device is triggered, and the triggering device is a cable; 
           [0025]      FIG. 12  shows another state of  FIG. 11 , wherein the spherical elements are between the upper detent elements and the middle detent elements; 
           [0026]      FIG. 13  further shows another state of  FIG. 11 , wherein the spherical elements engage with the middle detent elements; 
           [0027]      FIG. 14  shows a sectional view of a second embodiment, wherein the triggering device is a push rod; and 
           [0028]      FIG. 15  shows a perspective view of the outer tube of a third embodiment, wherein the outer tube consists of lour inner pieces and an outer sleeve. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0029]    The present invention will be dearer from the following description when viewed together with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiment in accordance with the present invention. 
         [0030]    Referring to  FIGS. 1-4 , the first embodiment of a multi-position adjustable height seat post in accordance with the present invention is usually mounted on the frame of a bike (not shown) and essentially to comprises an inner tube  1 , an outer tube  2 , a locking assembly  3 , a triggering device  4 , a first extending element  5 , and a second extending element  6 . 
         [0031]    The inner tube  1  comprises an upper end  11  and a lower end  12 . The outer tube  2 , consisting of an inner sleeve  21  made of steel and an outer sleeve  22  made of aluminum, comprises an upper end  23  and a lower end  24 . Preferably the hardness of the inner sleeve  21  is higher than 200 Vickers Pyramid Number. The outer tube  2  has a diameter greater than that of the inner tube  1 , and the outer tube  2  is configured to allow at least a portion of the lower end  12  of the inner tube  1  to slide into the upper end  23  of the outer tube  2 . 
         [0032]    The outer tube  2  is configured at its lower end  24  to be received by a standard seat tube receptacle of a bicycle frame (not shown) in the same manner as a standard bicycle seat post. The upper end  23  of the outer tube  2  is configured to accept the lower end  12  of the inner tube  1 . The upper end  11  of the inner tube  1  is assembled with a mounting mechanism  100  suitable to accept a bicycle seat (not shown) and the weight of a bicycle rider. 
         [0033]    Referring to  FIGS. 4-7 , the locking assembly  3  is for locking, unlocking and preventing rotation of the inner tube  1  with respect to the outer tube  2 . The locking assembly  3  comprises an actuating unit  31 , a pressure tube  32 , a plurality of straight parallel grooves  33  located in vertical alignment along a portion of the outer tube  2 , a plurality of spherical detent elements  34  located in the straight parallel grooves  33  of the outer tube  2 , and a plurality of spherical elements  35 . 
         [0034]    The actuating unit  31  is defined by an actuating element  311  and a locking element  312  configured on the actuating element  311 . The parallel grooves  33  are spaced apart angularly by 45°, 90°, 135° and 90° . The shapes of the detent elements  34  are not limited to spherical. The spherical elements  35  located, in the inner tube  1  between the locking element  312  and the outer tube  2 . Referring to  FIGS. 8-10 , the shapes of the detent elements  34  are spherical, cylindrical and annular respectively. 
         [0035]    The triggering device  4  is a cable in this embodiment. The cable  4  passes through the pressure tube  32  to the upper end  11  of the inner tube  1  for actuation by rider. 
         [0036]    The actuating element  311  contains a cylinder  3111  with the pressure tube  32  disposed inside, a cable head seat  3112 , a first seal  3113  and a seal screw  3114 . The head of the cable  4  is fixed on the cable head seat  3112 . The seal screw  3114  is to fix the head of the cable  4  in the cable head seat  3112 . The first seal  3113  is disposed between the bottom of the actuating element  311  and the seal screw  3114 . 
         [0037]    The pressure tube  32  contains a through hole  321  for the cable  4 , a piston portion  322  thrilled on the lower end and disposed in the cylinder  3111  of the actuating element  311 , and a second seal  323  configured between the piston portion  322  and the cylinder  3111 . 
         [0038]    The locking element  312  contains a first ramp section  3121 , a second ramp section  3127  and an accommodated room  3123  which is formed below the second ramp section  3122 . The first ramp section  3121  is steeper than the second ramp section  3122 . 
         [0039]    The first extending element  5  acts with constant spring force upon top of the locking element  312  to move the actuating element  311  and locking element  312  longitudinally downward inside the inner tube  1 . The first extending element  5  is a compression spring in this embodiment. The downward direction defines a first direction. 
         [0040]    The second extending element  6  includes a valve  61  and a compression room  62 . The valve is configured to introduce air into the compression room  62  and disposed at the lower portion of the outer tube  2 . The compression roam  62  is defined by the area inside the inner tube  1  and outer tube  2 , extending from the valve  61  at the lower portion of the outer tube  2  to the upper portion of the inner tube  1 . The position of the valve  61  is not limited to this embodiment. The second seal  323  of the pressure tube  32  isolates the compression room  62  from the atmosphere. 
         [0041]    Referring to  FIG. 5 , the multi-position adjustable height seat post is at a locked position. The spherical elements  35  engage with the spherical detent elements  34  respectively, and the inner tube  1  cannot move with respect to the outer tube  2 . When the seat post is at the locked position and the triggering device  4  is triggered, referring to 
         [0042]      FIG. 11-13 , the triggering device  4  moves upward, pulling up the actuating unit  31 , disengaging the locking element  312  and the spherical elements  35 , allowing the spherical elements  35  to disengage with the spherical detent elements  34  and slide from the first ramp section  3121  through the second ramp section  3122  into the accommodated room  3123 . The upward direction defines a second direction. 
         [0043]    The multi-position adjustable height seat post is at a free position after the actuation because the spherical elements  35  have moved inward out of the spherical detent elements  34  and can now slide in the grooves  33 . This allows the inner tube  1  to move with respect to the outer tube  2  in the longitudinal direction. If the rider weights the saddle (not shown), the inner tube  1  will lower decreasing the volume of the compression room  62  and increasing the inside air pressure. 
         [0044]    When the triggering device  4  is released, referring to  FIG. 13 , the triggering device  4  moves downward and the first extending element  5  will force the actuating unit  31  to move downward, pushing the spherical elements  35  outward by means of the first ramp section  3121 . This allows the spherical elements  35  to engage with the lower spherical detent elements  34  when the inner tube  1  has lowered to corresponding height. 
         [0045]    The current preferable number of spherical elements  35  is four. However, any number of spherical elements  35  could be used. The spherical elements  35  protrude outward through four holes  13  in the inner tube  1  contacting the outer tube  2  in either a plurality of spherical detent elements  34  or a plurality of grooves  33 . 
         [0046]    The currently preferred number of spherical detent elements  34  is 12. However, there are various possibilities with regards to the number of spherical detent elements  34  within the outer tube  2 . 
         [0047]    The currently preferred numbers of sets of spherical detent element  34 , which positions along the vertical axis of the outer tube  2 , are three. However, there are various possibilities with regards to the number of spherical detent element  34  within the outer tube  2 . 
         [0048]    The currently preferred positions of spherical detent elements  34  are at zero, one and four inches along the vertical axis of the outer tube  2 . However, there are various possibilities with regards to the position of spherical detent elements  34  within the outer tube  2 . 
         [0049]    The currently preferable numbers of parallel grooves  33  within the outer tube  2  are four. However, there are various possibilities with regards to the number of parallel grooves  33  within the outer tube  2 . 
         [0050]    The spherical elements  35  are used both as guides, tracking along parallel grooves  33  within the outer tube  2 , and function for locking when forced into spherical detent elements  34  on the outer tube  2 . As guides, the spherical elements  35  track from detent element  34  to detent element  34  along the parallel grooves  33  of the outer tube  2  respectively, preventing rotational movement of the outer tube  2  with respect to the inner tube  1 . 
         [0051]    Referring to  FIG. 6 , the multi-position adjustable height seat post further comprises a collar  7 , a third seal  8 , a fourth seal  9  and a fifth seal  10 . The collar  7  is assembled on the top of the outer tube  2 . The third seal  8  is disposed between collar  7  and the inner tube  1 . The fourth seal  9  is disposed below the third seal  8  and between collar  7  and the inner tube  1 . The fifth seal  10  is disposed between the collar  7  and the outer tube  2 . 
         [0052]    Referring to  FIG. 14 , the second embodiment of a multi-position adjustable height seat post comprises a triggering device  4  which is a push rod connected to the actuating unit  31 . 
         [0053]    Referring to  FIG. 15 , the third embodiment of a multi-position adjustable height seat post comprises an outer tube  2 , consisting of an outer sleeve  22  and four inner pieces  21  made of steel. 
         [0054]    To sum up the above statements, the multi-position adjustable height seat post has several obvious advantages below: 
         [0055]    First, the internal locking mechanism improves external appearance of the inner tube  1 . It hides wear damage of the interface inside on the outer tube  2  for a like new external appearance in comparison with the U.S. Pat. No. 8,079,772 patent. 
         [0056]    Second, the smooth circular inner tube  1  provides a proper to sealing surface for wiper seal preventing dirt, water, and other contaminants from entering inside mechanism. 
         [0057]    Third, it allows for weight reduction in virtue of the replacing of coil spring with air spring (second extending element  6 ). 
         [0058]    Fourth, the wear resistance is better in virtue of the steel material of the inner sleeve  22  of outer tube  2 . 
         [0059]    Fifth, its easier to fabricate in virtue of the outer tube  2  consisting of two separate pieces. The manufacturer can machine the inner piece  21  and the outer piece  22  individually. 
         [0060]    While we have shown and described various embodiments in accordance with the present invention, it is clear to those skilled in the art further embodiments may be made without departing from the scope of the present invention.