Patent Publication Number: US-2007110589-A1

Title: Integrated bicycle air pump

Description:
TECHNICAL FIELD  
      The present invention relates generally to accessories for bicycles, and more particularly, to an air pump integrated as part of a bicycle.  
     BACKGROUND  
      Many bicyclists carry portable air pumps with them while riding to have them conveniently available to maintain proper air pressure in their tires, such as to refresh a slowly leaking tire. This also avoids the hassle of having to transport their bicycle to a repair shop or gas station to inflate their tires. Most modern portable air pumps are mountable on the bicycle frame to avoid the bicyclist having to carry the pump on their person while riding, which can be awkward and inconvenient.  
      However, there are drawbacks associated with mounting air pumps on the bicycle frame. For instance, pumps mounted to the bicycle frame may become dislodged and fall off, if jarred when riding over rough terrain. Additionally, pumps mounted to the bicycle frame, may become tempting items for thieves. Accordingly, when leaving their bike unattended when out riding, it is common for a bicyclist to remove their air pump from the frame and carry it with them.  
      Other drawbacks associated with portable air pumps are their inherent physical shortcomings. For example, a sufficient quantity of energy is required to inflate a tire, and for a conventional portable air pump the bicyclist usually compresses the air by pushing directly on a piston using a hand pumping motion. The compressive force required on the piston often becomes excessive at higher air pressures requiring substantial strength to move the pumping mechanism to push air into the tire. For example, it may take approximately 65 pounds of pressure to fully inflate a bicycle tire. Furthermore, it may require many strokes and substantial time to inflate a tire to its proper pressure due to the compact size of conventional portable air pumps, and their inability to produce sufficient quantities of air per stroke.  
      Another drawback of many portable air pumps involve the bicyclist having to bend down to the tire&#39;s level in an uncomfortable kneeling or bent over position and remain in this position while pumping the tire.  
      Still another drawback of many portable bicycle air pumps is that they tend to be expensive, as they are often constructed of lighter and inherently costlier materials to reduce weight and bulkiness.  
     SUMMARY  
      Briefly, this invention is directed to an air pump integrated, in at least in part, in a seat tube of a frame of a bicycle. A flange is interposed between a seat post and the seat tube. The flange is secured to the seat post in a sliding abutment relationship with the seat tube. A seal located in a lower portion of the seat tube provides an air closure (i.e. an air seal). Hollow space between the flange and the seal in the seat tube form an air chamber for the air pump. A vent hole passes through the seat tube proximal to the air chamber. When the seat post is slid in a downward direction into the seat tube air is pressurized within the air chamber for expulsion through the vent hole.  
      In another embodiment, a kit may be sold to bicycle repair shops and bicyclists that enables a user to retrofit a bicycle to include an integrated bicycle pump. The kit may include: a flange, a connection member, and a hose. The flange is secured to the seat post. A vent hole is drilled into the seat tube, and the connection member is mounted therein. The hose may be removeably secured to the connection member. Instructions describing how to retrofit a bicycle may accompany the kit or may be available from a web site.  
      This invention introduces the broad concept of creating an integrated bicycle air pump substantially out of standard bicycle parts in combination with only a few additional components. In particular, the combination of the seat post and the flange secured thereto form a piston of the integrated air pump. The bicycle seat serves as a handle for moving the piston up and down, and the seat tube form a housing for the piston. A vent hole in the seat tube proximal to the air chamber serves as an outlet for the integrated air pump, which enables a flexible hose to be connected for inflating tires, balls, rafts and other inflatable items.  
      This invention eliminates the need to purchase separate portable hand pumps for bicycles. Accordingly, most bicycles may be manufactured or retrofitted to include an air pump, simply by adding minimal extra parts per bicycle, such as a flange and a connection member. The additional extra parts add less than a few ounces of weight to the bicycle, and weigh less than most conventional portable tire pumps. Additionally, the parts are inexpensive, and usually do not require modification to the overall structure or design of the bicycle other than a small vent hole in the seat tube. It is noted that the seal used to plug the lower portion of the seat tube may or may not be needed depending on the construction of the seat tube. The seal may be constructed of inexpensive and lightweight material, such as rubber, metal, foam, or other suitable materials able to make the bottom of the seat tube generally air tight when air is compressed within the seat tube.  
      Another advantage of the integrated pump is the ability to pump bicycles tires while standing in a comfortable erect position. Once the hose is connected to a tire, the user of the pump moves the bicycle seat up and down, which admits air from the air chamber into the tire. The user of the innovative pump may simply push down on the bicycle seat using body weight rather than having to use shoulder and arm strength as is often the case with conventional portable pumps. Thus, yet another advantage of the innovative integrated pump is the ability to manually pump bicycle tires without having to use as much strength as a conventional portable bicycle air pump.  
      Another advantage of the innovative air pump is its ability to fully pump a tire to its proper pressure in less time than most conventional portable hand pumps, due to the larger size of the seat tube&#39;s air chamber when compared to many air chambers associated with conventional portable hand pumps. That is, the innovative pump described herein is able to produce larger quantities of air per stroke to pump into a tire. It is also easier to handle of the innovative integrated pump as it uses a much larger piston, i.e., the combination of seat, seat post and flange, when compared to many conventional portable bicycle air pumps.  
      Still a further advantage of the invention, is the convenience of always having a built-in air pump available as part of a bicycle, for inflating the tires of the bicycle or possibly other inflatable items. This invention eliminates many of the inconveniences associated with mounting a separately purchased air pump on a bicycle frame or other inconveniences such as searching for a repair station.  
      Further features and advantages of the present invention may become apparent after reading the Detailed Description section in conjunction with the drawings.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The detailed description is presented with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. It is emphasized that the various features in the figures are not drawn to scale, and dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. Reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:  
       FIG. 1  is a partial view of a bicycle.  
       FIG. 2  shows a grommet or o-ring (collectively a flange) fitting around the outer circumference of a seat post.  
       FIG. 3  shows a cross section view taken along line  3 - 3  of  FIG. 2 .  
       FIG. 4  shows a bicycle post sliding upward within a bicycle tube.  
       FIG. 5  shows a bicycle post sliding downward within a bicycle tube.  
       FIG. 6  shows a cross sectional view of a connection member proximal to an air chamber of the innovative air pump.  
       FIG. 7  shows a side view of a bicycle with an integrated pump therein.  
       FIG. 8  illustrates an aftermarket kit that may be used for converting a seat tube and a seat post of a frame of a bicycle (such as shown in  FIGS. 1-7 ) into an integrated air pump.  
    
    
     DETAILED DESCRIPTION  
      Reference herein to “one embodiment”, “an embodiment”, or similar formulations, means that a particular feature, structure, operation, or characteristic described in connection with the embodiment, is included in at least one embodiment of the present invention. Thus, the appearances of such phrases or formulations herein are not necessarily all referring to the same embodiment. Furthermore, various particular features, structures, operations, or characteristics may be combined in any suitable manner in one or more embodiments.  
      Referring initially to  FIG. 1  is a partial view of a bicycle generally shown as reference number  100 . In particular,  FIG. 1  shows a center portion of a bicycle frame  102  partly in cross section. Frame  102  includes a seat tube  104  (tube  104 ) with an opening  107  for receiving a seat post  106  (post  106 ) therein. Tube  104  is usually hollow in construction with an inner portion (or inner wall)  109  and an outer portion (or exterior wall)  111 .  
      Typically, post  106 , which is of a smaller concentric shape than tube  104 , has an exterior surface  114  that fits within inner portion  109  of post  106 . Post  106  has a large enough length to slide securely up and down within seat tube  104 , in a concentric fashion. The ability to adjust the height of a bicycle seat  108  by sliding post  106  up or down is a fairly common feature of most bicycles, normally to accommodate different sized bicyclists. Typically, post  106  can slide up by lifting-upwards on seat  108 , and can slide down by pushing downward on seat  108 . Lubricants, such as oil or grease, allow post  106  to slide smoothly up and down (longitudinally), within tube  104 .  
      A seat release mechanism, such as a threaded bolt or quick release lever  110 , when loosened or placed in a release position, loosen a clamp (not shown) at opening  107 . While the clamp is loosened, post  106  is able to slide freely in a longitudinal direction within tube  104  by pushing downward or pulling upward on seat  108 . Conversely, when the clamp is tightened (e.g., seat release mechanism  110  placed locked into a non-release position) seat  108  is secured at a fixed height. For purposes of discussion herein, it assumed that release mechanism  110  is generally in a position to allow post  106  to slide freely up or down within tube  104 .  
      Having introduced conventional features of most bicycles, it is now possible to describe embodiments of an innovative air pump integrated within bicycle  100  and using many standard parts of a bicycle.  
      Briefly, innovative air pump, referred to generally as reference number  116 , includes one or more of the following components: a flange  118 , a seal  120 , a connection member  122 , and a hose  124 . As shall be explained these components in combination with the aforementioned parts of most conventional bicycles form innovative air pump  116 . Each component and its interrelationship with bicycle  100  shall now be explained in greater detail.  
      Flange  118  is generally a flexible or semi-rigid material (such as rubber, plastic, neoprene, foam, or other suitable materials including composite materials) that may be configured in a variety of shapes and sizes able to be disposed between an inner wall  109  of tube  104  and an exterior portion  114  of post  106 . For instance, in the illustrative embodiment of  FIG. 1 , flange  106  is a rubber grommet that fits between exterior portion  114  of post  106  and inner wall  109  of tube  104 . Accordingly, when post  106  is inserted into tube  104 , flange  118  remains coupled to post  106 , and is interposed between post  106  and tube  104 . That is, flange  118  is coupled to post  106  in a sliding abutment relationship with inner wall  109  of tube  104 . Flange  118  typically presses against inner wall  108  in a resilient manner. In one embodiment, flange  118  has an outer portion  128  that extends beyond exterior portion  114  of post  106 .  
      In alternative embodiments, flange  118  may be implemented as an o-ring, a disc, a flexible diaphragm, or any customized or off-the-shelf element suitable for use as a plunger of an air pump, i.e. a moveable seal for compressing air in the air chamber of an air hand pump.  
      Flange  118  may be secured to a bottom  125  of post  106  by any suitable manner. For instance, flange  118  may be mounted to bottom  125  by a bolt/washer (not shown), a backing plate (not shown), by glue, Velcro, adhesive, or other suitable fastening mechanisms. Flange  118  may also be an integral part of post  106 .  
      Alternatively, flange  118  may be secured around an exterior portion  114  of post  106  in a concentric fashion, such as shown in  FIG. 2 . In the illustrative embodiment of  FIG. 2 , flange  118  is a rubber o-ring that fits in a groove  202  within exterior portion  114  of post  106 . Flange  118  may also be glued or held in place by a pin (not shown), rod (not shown) or any other suitable fastening mechanism for securing flange  118  to exterior portion  114  of post  106 .  FIG. 3  shows a cross section view taken along line  3 - 3  of  FIG. 2 . In the illustrative embodiment of  FIG. 3 , flange  118  is disposed between inner wall  109  of tube  104  and exterior portion  114  of post  106 .  
      In one implementation, flange  118  may flex and compress in shape. For example, when seat  108  is pulled upward causing post  106  to slide upward within tube  104 , flange  118  flexes downward as its edges  402  slide against inner wall  109  of tube  104  (see  FIG. 4 ). As shall be explained, this flexing of flange  118  permits ambient air to flow past edges of flange  118  in a downward direction into an air chamber  132  (to be explained), filling a vacuum.  
      In contrast, when seat  108  is pushed downward causing post  106  to slide downward within tube  104 , flange  118  compresses in shape, causing edges  402  to thicken as edges  402  slide against inner wall  109  (see  FIG. 5 ). As shall be explained, compression of flange  118  creates an air dam preventing air from flowing past flange  118  as air is compressed within air chamber  132 . Therefore, flange  118  acts as a piston (or air dam) and pushes air out of an air chamber  132  (see  FIG. 1  to be explained) while seat  108  is pushed downward.  
      Referring back to  FIG. 1 , seal  120  is a plug located in a lower portion  130  of tube  104  and provides an air closure blocking air from flowing past seal  120 . In other words, seal  120  blocks air from entering or exiting gaps or openings (not shown) of lower portion  130  of tube  104 .  
      Seal  120  may be of any material suitable for serving as an air closure inside tube  104 . For example, seal  120  may be foam, plastic, rubber, epoxy, adhesive, metal, paper, sponge, cardboard, a composite material, or a combination of the aforementioned. Although seal  120  is illustrated as being single thin piece of material, it may be of various dimensions, and may not be even or uniform in shape, such as in the form of an a sealant such as epoxy or glue used for sealing gap(s) (not shown) in lower portion  130 . Seal  120  may also be an integral part of frame  102 . When implemented as a fixed structure, seal  120  may be secured in place by various means, depending on the type of material selected for seal  120 . For example, if in the form of a liquid applied drying sealant, such as glue, seal  120  will stick to inner portions of frame  102 . If of a different material such as plastic, rubber or material, seal  120  may be held in place by finishing to the surface of inner wall  109  or by other means, as those skilled in the art would readily appreciate.  
      Hollow space in the interior of tube  104 , between flange  118  and seal  120  forms an air chamber  132 . Accordingly, when post  106  is slid downward into tube  104 , flange  118  moves toward seal  120  and acts as a piston. Flange  118  compresses air within air chamber  132 . Pressure build-up in chamber  132  causes air therein to exit air chamber  132  via an air vent  121  located within connection member  122 . Air vent  121  provides an air pathway for air to pass from inside chamber  132  to the exterior of tube  104  via connection member  122 . That is, air pressure within air chamber  132  increases when post  106  is slid in a downward direction into tube  104  thereby causing flange  118  to slide with post  106  against inner wall  109  of tube  104  and push air out of vent hole (also referred to as air vent  121 ).  
      On the other hand, a reverse stroke of pump  116  occurs, when flange  118  is moved upward by pulling seat  108  in an upward direction. This action creates a vacuum in air chamber  132 , which causes ambient air to enter air chamber  132  by flowing past flexed edges  402  (see also  FIG. 4 ) of flange  118 . That is, ambient air enters air chamber  132  when post  106  is slid in an upward direction thereby causing flange  118  to slide with post  106  against inner wall  109  of tube  104 . A vacuum is simultaneously created by the action of flange  118  moving upward creating a greater volume void within tube  104 , which causes ambient air to rush-in chamber  132  to fill the lower pressurized chamber  132 . Thus, the ambient air flows past edges  402  ( FIG. 4 ) of flange  118  between flange  118  and inner wall  109 , and enters air chamber  132 . At this point, a down stroke pump  116  can occur as explained above by pushing down on seat  108 . The process of down strokes and up strokes may repeat several times until a desired pressure is reached in the vessel being inflated, such as a bicycle tire.  
      In one embodiment, connection member  122  is generally a closed body providing a pathway for air to exit air chamber  132  into hose  124 , such as when post  106  is slid downward pumping compressed air into chamber  132 .  FIG. 6  shows a cross sectional view of connection member  122  according to one exemplary embodiment.  
      Referring to  FIG. 6 , connection member  122  includes walls  602  that pass through inner and outer portions  109 ,  111  of tube  104 . Walls  602  are either integral to inner and outer portions  109 ,  111  of tube  104 , are connected thereto by an air tight sealant such as epoxy and/or solder, or are connected by other suitable means as will be appreciated by those skilled in this field and having the benefit of the present disclosure. Vent hole  121  may be drilled through tube  104 , or may be punch pressed item and integrated therein. In one embodiment, vent hole  121  has a diameter of 0.25 inches.  
      Connection member  122  includes a check valve  604 . In one implementation, check valve  604  includes a ball  606  configured to cover and seal a hole  608 . In turn, ball  606  prevents air from flowing from hose  124  into air chamber  132  when post  106  and flange  118  are moved upward. As mentioned earlier when flange  118  is moved upward it creates a vacuum in air chamber  132  (see also  FIG. 4 ), and forces ambient air to enter air chamber  132  around flexed edges  402  (see also  FIG. 4 ) of flange  118 . Again, ball  606  prevents air from entering air chamber  132  when this vacuum is created.  
      On the other hand, when post  106  is slid downward (see also  FIG. 5 ) into tube  104 , flange  118  slides toward seal  120  pressurizing air within chamber  132  for expulsion through the vent hole forcing air to compress in air chamber  132  and exit air vent  121 . Exiting air flows up through hole  608  past ball  606 , causing ball  606  to float. The air then flows around the levitating ball  606  and exits hole  612  and into hose  124 . A wire  610  prevents ball  606  from being pushed-up into hole  612  and block hole  612  when air exits connection member  122 . Alternatively, a bar (not shown) or other restraint structure may also be used to contain ball  606 . Ball  606  may be made of various materials such as rubber, Styrofoam, plastic, or other suitable materials. Additionally, it will be appreciated by those skilled in this field and having the benefit of the present disclosure, that check valve  604  may be implemented using a one-way diaphragm valve instead of a ball, or by other suitable means.  
      Connection member  122  also provides a means for attaching hose  124 . In one embodiment, hose  124  is releasably engaged/disengaged to connection member  122 . Hose  124  may be engaged/disengaged by a connection interface  150 , such as threaded screw interface, bayonet twist-on/twist-off mechanisms, snap-on/snap-off mechanisms, or by other suitable connection mechanisms. Alternatively, hose  124  may be an integrated part of connection member  122 .  
      Referring back to  FIG. 1 , hose  124  is generally made of flexible material(s) such as rubber or other materials commonly used with manual air pumps. Hose  124  is preferably long enough to reach the front and rear tires of a bicycle, but may be of different lengths depending on the size of a bicycle and its tires. At the distal end of hose  124  is an inflation valve  152  for engaging the valve (not shown) of a bicycle tire. Alternatively, inflation valve  152  may include interchangeable parts configured to mate with other inflation interface mechanisms, such as a pin for interfacing with an intake valve of a ball (e.g., beach ball, football, soccer ball, etc.). An air gauge (not shown) may be included as part of pump  116 .  
      It will be appreciated by those skilled in this field and having the benefit of the present disclosure, that flange  118  may be implemented using a non-flexible material. Accordingly, flange  118  may provide a permanent seal when post  106  is slid upward or downward. In such an exemplary implementation, a check valve (not shown) may be implemented in seal  120  (or other location within frame  102 ) that allows air to flow into chamber  132  when post  106  is slid upward, and seals itself when post  106  is slid downward. Accordingly, check valve  604  is optional and may be implemented in another portion of pump  116 .  
       FIG. 7  shows a side view of bicycle  100  with an integrated pump  116  therein. In particular,  FIG. 7  shows that hose  124  may be held onto frame  102  by attachment elements  702  (see  FIG. 7 ), such as clips, Velcro straps, or other suitable restraint pieces.  
       FIG. 8  illustrates an aftermarket kit  802  for converting a seat tube and a seat post of a frame of a bicycle (such as shown in  FIGS. 1-7 ) into an integrated air pump such as the foregoing pump  116 . Kit  802  may be sold as a package directly or indirectly to bicyclists and bicycle retail/repair shops.  
      In one implementation, kit  802  includes a grommet  804  securable to the seat post (such as  106 ) of a bicycle. Grommet  804  (also referred to as a flange) is adapted to be interposed between the seat post and an inner wall (e.g.,  109  of  FIG. 1 ) of a seat tube. Grommet  804  when installed on the bottom of seat post such as shown in  FIGS. 1, 2  and  3  is also configured to be in sliding engagement with the inner wall of the seat tube.  
      Kit  802  may also include a coupling mechanism (such as connection member  122  shown in  FIGS. 1 and 6 ) configured to provide an air conduit between a vent hole (e.g.,  121  of  FIGS. 1 and 6 ) and a hose  124  ( FIGS. 1 and 6 ), the vent hole  121  ( FIGS. 1 and 6 ) passing through a wall of the seat tube  104  into a hollow portion of the seat tube forming an air chamber  132  ( FIGS. 1 and 6 ) therein.  
      Kit  802  may also include a hose, such as hose  124  ( FIGS. 1 and 6 ), which also may include a coupling mechanism such as connection mechanism  150 . Kit  802  may also include a plug, such as seal  120  ( FIG. 1 ) for providing an air seal at a location within the seat tube below the vent hole.  
      It should also be appreciated that kit  802  may include instructions describing how to install the grommet, the coupling mechanism, and the hose to construct an integrated air pump  116  ( FIG. 1 ) partially within bicycle  100 . The instructions may be in paper form or available electronically, such as from a web site.  
      The embodiments described herein are to be considered in all respects only as exemplary and not restrictive. The scope of the invention is, therefore, indicated by the subjoined Claims rather by the foregoing description. All changes which come within the meaning and range of equivalency of the Claims are to be embraced within their scope.