Abstract:
An adjustable cycle seat includes a seat post configured as an I-beam with front and rear flanges and a web therebetween defining side channels. A sleeve about the post is attached to the cycle. At least one spring is interconnected between the post and the sleeve biasing the post upward. An actuatable locking mechanism releasable secures the post to the sleeve.

Description:
FIELD OF THE INVENTION 
       [0001]    The subject invention relates to adjustable cycle (e.g., bicycle) seats. 
       BACKGROUND OF THE INVENTION 
       [0002]    Conventional bicycle seats are raised and lowered via a clamp assembly releasably positioning the seat post with respect to a sleeve fixed to the bicycle frame. 
         [0003]    For some applications, on-the-fly seat adjustment is desirable. For example, a mountain bike rider may want the seat higher while on gentle terrain but lower while traversing more challenging terrain. Accordingly, on-the-fly designs typically include a lever on the handle bar actuating a cable leading to a mechanism on the seat sleeve which allows the seat post to be adjusted relative to the sleeve. See, for example, U.S. Pat. Nos. 8,136,877 and 6,354,557 as well as U.S. published application no. 2012/0104810 all incorporated herein by this reference. 
         [0004]    Some of these designs are not strong enough to meet the specifications of bicycle manufacturers. Mountain bikes, in particular, experience severe loads on the seat post. Also, some designs have cables which extend perpendicular to the seat sleeve resulting in possible irritation to the rider. 
         [0005]    Gas spring designs, in turn, may result in limited seat post travel, add weight, and may pose reliability and/or maintainability concerns. 
       SUMMARY OF THE INVENTION 
       [0006]    In one aspect, a new adjustable seat is provided which is strong, light weight, and reliable. 
         [0007]    Featured is an adjustable cycle seat comprising a post supporting a seat clamp and configured as an I-beam with front and rear flanges and a web therebetween defining side channels. A sleeve about the post is attached to the cycle. At least one spring is interconnected between the post and the sleeve biasing the post upward. An actuatable locking mechanism releasable secures the post to the sleeve. 
         [0008]    The spring may reside in at least one or both side channels. Preferably, the locking mechanism interacts with the front flange to releasable lock the post to the sleeve. In one design, the locking mechanism includes a fork member engaging a spaced series of notches in the front flange. The fork member is moveably disposed in the sleeve. The fork member may be biased into engagement with the post. The locking mechanism may further include a cable mechanism for retracting the fork member. One cable mechanism includes a cable stop aligned with the sleeve and a wedge member for retracting the fork member disposed in a well in the fork member. In one design, at least one boss is attached to the sleeve and extends into a said side channel to prevent rotation of the post in the sleeve. There may be orifices in the web for stop members. 
         [0009]    In another design, the locking mechanism includes a retractable pin engaging the web of the post. 
         [0010]    The subject invention, however, in other embodiments, need not achieve all these objectives and the claims hereof should not be limited to structures or methods capable of achieving these objectives. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0011]    Other objects, features and advantages will occur to those skilled in the art from the following description of a preferred embodiment and the accompanying drawings, in which: 
           [0012]      FIG. 1  is a schematic three dimensional front view of a prior art adjustable seat post and sleeve; 
           [0013]      FIG. 2  is schematic three dimensional front view of an example of an adjustable seat mechanism in accordance with the subject invention; 
           [0014]      FIG. 3  is an exploded view showing the primary components of the example of  FIG. 2 ; 
           [0015]      FIG. 4  is a schematic front view of the novel seat post of  FIGS. 2 and 3 ; 
           [0016]      FIG. 5  is a schematic three dimensional top view showing a portion of the seat post and sleeve assemblies; 
           [0017]      FIG. 6  is a schematic three dimensional view showing the seat post and the fork member of the locking mechanism; 
           [0018]      FIG. 7  is a view showing the primary components associated with the locking mechanism; 
           [0019]      FIG. 8  is a schematic three dimensional view of the seat post now disposed in the bicycle frame and including a constant force spring for biasing this seat post upwards; 
           [0020]      FIG. 9  is a schematic three dimensional side view of a prototype example of the invention showing the use of a different kind of spring; 
           [0021]      FIG. 10  is a schematic three dimensional view showing an example of a seat post with an integral pumping subsystem piston mounted in a portion of the bicycle seat frame configured as a cylinder for the post piston; 
           [0022]      FIG. 11  is a schematic view of another version where the pump cylinder is a liner set in the bicycle frame member; 
           [0023]      FIG. 12  is a partial cross-section view showing the air path; and 
           [0024]      FIGS. 13A-13B  are schematic views showing a side locking pin design in accordance with examples of the invention. 
       
    
    
       [0025]    The subject invention, however, in other embodiments, need not achieve all these objectives and the claims hereof should not be limited to structures or methods capable of achieving these objectives. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0026]    Aside from the preferred embodiment or embodiments disclosed below, this invention is capable of other embodiments and of being practiced or being carried out in various ways. Thus, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. If only one embodiment is described herein, the claims hereof are not to be limited to that embodiment. Moreover, the claims hereof are not to be read restrictively unless there is clear and convincing evidence manifesting a certain exclusion, restriction, or disclaimer. 
         [0027]      FIG. 1  shows prior art adjustable seat mechanism  12  with post  14  supporting seat clamp  16 . Post  14  is adjustable with respect to sleeve  18 . Post  14  has front channel  20  (and a rear lengthwise hole (not shown)). Inner wall  22  has a number of detents  24 . 
         [0028]    Cable  26  is activated by a handle bar mounted lever to drive a pin extending through sleeve  18  into and to retract it from one of the detents  24 . A spring, not shown, extends from the top of the rear hole, around pulley  27 , and into front channel  20  and biases the post upwards. 
         [0029]    Because front channel  20  and/or the lengthwise hole weakens post  14  in the direction of the main load experienced by the post (the seat is shown in relief at  30 ), this design may not pass the specifications of bicycle manufacturers. 
         [0030]    In the new design, shown by way of example in  FIG. 2 , the seat post  32  is configured as or like an I-beam with curved front  34   a  and curved rear  34   b  flanges connected via web  36  defining opposing side channels (side channel  38   a  is shown). Post  32  supports seat clamp  38  for seat  30 . This configuration for post  32  results in a higher cross sectional moment of inertia and thus higher strength for repeated loads experienced by post  32  which is angled rearwardly with respect to the bike frame. 
         [0031]    Sleeve  40  is attached to the bike frame and post  32  is moveable within sleeve  40 . Locking mechanism  42 ,  FIGS. 2-3  and  FIGS. 5-7  is associated with sleeve housing portion  50  and releasably secures the post in one of a number of positions relative to sleeve  40 . A spring mechanism  308  biases post  32  upwards. The spring or springs preferably reside in the side channels (e.g., side channel  38   a ) as discussed below and extends around pulley  309  at the bottom of post  32  up to sleeve  40  where it is fixed to the sleeve via pin  311 . 
         [0032]    As shown in  FIG. 3  where sleeve housing portion  50  is shown separately from sleeve  40 , locking mechanism fork member  52  interacts with front flange  34   a  and the spaced series of notches  54  therein (e.g., a series of pairs of notches, each pair at a different elevation on post  32 ,  FIG. 4 ). The spaced prongs  60   a  and  60   b  of fork  52  releasably engage these notches. Fork  52  is preferably movably disposed in housing  50  of sleeve  40  and biased into engagement with post  32  by one or more springs  90 . A cable  92 ,  FIG. 2  extending from cable stop  62  is connected to a lever  302  mounted to the bike handle bars and retracts fork  52 ,  FIG. 3  to adjust seat post  32  up and down relative to sleeve  40 . As shown, it is preferred that cable stop  62 ,  FIG. 2  be angled substantially downward to minimize interference with the cable. Other means for activating the locking mechanism to adjust the seat are possible. 
         [0033]    In this particular design, boss  70 ,  FIGS. 3 and 5  are attached to sleeve  40  housing  50  and extends into side channel  38   a  to prevent rotation of the post with respect to the sleeve. Orifices  74  in web  36  allow for the inclusion of stop members to limit the travel of seat post  32  to suit the rider&#39;s preference. 
         [0034]    Other release mechanisms are possible but it is preferred that they interact with the front (and/or rear) flange of the seat post. By not associating the release mechanism with the side channels (or the web member), there is no interference with the post spring or springs which can now be made longer to increase the travel of the seat post. But, these are preferred designs only. 
         [0035]      FIGS. 5-7  show housing  50  supporting locking mechanism  42 . The rear  88  of fork member  52  is biased forward so the fork members engage post  32 . Springs  90  push on the rear of fork member  52 . The cable  92 ,  FIG. 2  pulls fork member  52  rearward out of engagement of post  32  allowing it to move up and down for seat adjustment. Guide blocks  310   a  and  310   b  define the cable path in the preferred, downward direction. Releasing the cable forces fork member  52  into engagement with the post. 
         [0036]      FIG. 8  shows one embodiment in which a constant force spring  100  on a drum or in a pocket in the bottom of post  32  and anchored on one end  102  to the sleeve. This biases post  32  upward in sleeve  40  of bike frame  41 . 
         [0037]    In  FIG. 9 , spring  120  is attached at the bottom of post  32 , resides in channel  38   b , and is anchored to sleeve  40 . When the post is pushed down, the spring extends. Another spring could reside in the opposing I-beam member channel. Or, a spring or elastic cord (shock cord or bungee) could wrap around a pulley at the bottom of post  32  and anchor to opposite sides of the sleeve. This allows extra length for the spring to accommodate long travel wells into the post length. 
         [0038]      FIG. 10  shows a version with a piston  200  on the bottom of post  32 . Then, the bike frame member  202 , acts as a cylinder with an air outlet connected to hose  206  with tire filling nozzle  208  for pumping air into a bike tire by raising seat  30  up and down in a pumping action. Plug  312  seals the bottom of member  202 . 
         [0039]    Alternatively, a liner  209  can be placed in frame member  202 ,  FIGS. 11-12 . The air exit is now through a space between the liner and the frame member. 
         [0040]    In  FIG. 13A , the post  32  has front flange  34   a  and rear flange  34   b  and side channels  38   a  and  38   b.  Here pin  424  extends through sleeve  40  and into one of a number of orifices  74  in the web  36  between the side channels to releasably lock sleeve  40  with respect to post  32 . Cable  92  can be used to pull pin  424  out of an orifice  74  in web  36  for adjustment of post  32 . Spring  90  biases pin  424  into a locked position shown in  FIG. 13A . 
         [0041]    In  FIG. 13B , cable  92  now exits the front of the bike seat post assembly. Pulling on cable  92  rotates arm  425  about pin  426  compressing spring  90  and retracts pin  424  allowing the height of the seat to be adjusted. Again, pin  424  interacts with orifices in web  36 . 
         [0042]    Thus, although specific features of the invention are shown in some drawings and not in others, this is for convenience only as each feature may be combined with any or all of the other features in accordance with the invention. The words “including”, “comprising”, “having”, and “with” as used herein are to be interpreted broadly and comprehensively and are not limited to any physical interconnection. Moreover, any embodiments disclosed in the subject application are not to be taken as the only possible embodiments. 
         [0043]    In addition, any amendment presented during the prosecution of the patent application for this patent is not a disclaimer of any claim element presented in the application as filed: those skilled in the art cannot reasonably be expected to draft a claim that would literally encompass all possible equivalents, many equivalents will be unforeseeable at the time of the amendment and are beyond a fair interpretation of what is to be surrendered (if anything), the rationale underlying the amendment may bear no more than a tangential relation to many equivalents, and/or there are many other reasons the applicant can not be expected to describe certain insubstantial substitutes for any claim element amended. 
         [0044]    Other embodiments will occur to those skilled in the art and are within the following claims.