Abstract:
A self-adjusting bolt action skewer clamp for a bicycle trainer includes a hollow, outer support member and an inner engagement member located inside the support member. The support member has a helical slot with a pocket at one end. The inner engagement member is attached to a handle via a carrier contained within a passage defined by the inner engagement member, and the handle can slide within the helical slot such that the inner engagement member will extend past the support member as the handle is rotated around the helical slot. Once it reaches the pocket, the handle will remain locked in place. The clamp tightens onto a rear axle of the bicycle. The spring allows the bicycle trainer to accommodate bicycles of various sizes without adjustment.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority under 35 U.S.C. §119 based on U.S. Provisional Patent Application No. 61/708,321, which was filed on Oct. 1, 2012, the subject matter of which is incorporated by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates in general to the field of stationary bicycle trainers. More particularly, the present invention relates to the bolt mechanism that holds a bicycle in place on a bicycle trainer by clamping onto the bicycle axle or skewer. 
     2. Discussion of the Related Art 
     There are several types of bicycle trainers that hold a bicycle in a stationary position relative to a frame. These bicycle trainers employ a number of different mechanisms to secure the bicycle to the bicycle trainer, typically by clamping the ends of the bicycle skewer or axle. For instance, the bicycle skewer may be engaged by a mounting bolt that can be actuated to move toward and away from a stationary receiver. The position of the receiver must be adjusted in order to accommodate the specific distance between the ends of the skewer. Alternatively, a lead screw may be employed to move a clamping member toward and away from a stationary receiver. The lead screw actuator must be turned repeatedly in order to travel toward and away from the receiver to engage and disengage the skewer, respectively. Arrangements such as this are time-consuming and inconvenient when securing a bicycle wheel to a bicycle trainer or removing a bicycle from a bicycle trainer. 
     What is needed, therefore, is a securing mechanism that can easily be used to engage the axle or skewer of a variety of different types and styles of bicycles in a quick and convenient manner. 
     BRIEF DESCRIPTION OF THE INVENTION 
     By way of summary, the present invention is a self-adjusting bolt action skewer clamping mechanism capable of engaging the bicycle axle or skewer of a number of different types, sizes and styles of bicycle in a quick and easy manner. 
     In accordance with a first aspect of the invention, one side of the self adjusting bolt action skewer clamp mechanism in accordance with the present invention is configured to be fixed in a stationary position. The opposite side of the of the self-adjusting bolt action skewer clamp mechanism of the present invention is adjustable. The adjustable side features a spring positioned within a clamping member, which in turn is axially movable relative to a frame of the bicycle trainer, and which is movable back and forth in response to a bolt action type actuator movably mounted to the frame. One end of the spring is engaged with a pin located within a passage defined by the clamping member, and the other end of the spring is engaged with a carrier contained within the clamping member. The bolt action actuator is secured to and extends outward from the carrier, such that the carrier is movable along with the actuator during movement of the actuator. In use, the actuator is helically rotated to advance the clamping member. This moves the carrier and the clamping member outwardly due to engagement of the spring between the carrier and the pin. When the outer end of the clamping member engages the end of the skewer, continued advancement of the actuator advances the carrier, which compresses the spring. Once the lever is fully rotated, it locks the bicycle axle into place. The spring compression accommodates variations in bicycle skewer lengths, which allows different sizes and styles of bikes to be mounted to the trainer without wasting time previously required for adjusting a clamping mechanism. 
     These and other features and aspects of the present invention will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following description, while indicating a representative embodiments of the present invention, is given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A clear conception of the advantages and features constituting the present invention, and of the construction and operation of typical mechanisms provided with the present invention, will become more readily apparent by referring to the exemplary, and therefore non-limiting, embodiments illustrated in the drawings accompanying and forming a part of this specification, wherein like reference numerals designate the same elements in the several views, and in which: 
         FIG. 1  is a perspective view of one embodiment of a bicycle trainer that features the self-adjusting bolt action skewer clamp of the present invention; 
         FIG. 2  is a partial cross section taken along line  2 - 2  of  FIG. 1 ; 
         FIG. 3  is a partial elevation view of the self-adjusting bolt action skewer clamp  FIG. 1  in an unlocked position; 
         FIG. 4  is a a partial elevation view of the self-adjusting bolt action skewer clamp  FIG. 1  in initial engagement position in which the end of the skewer is initially engaged; 
         FIG. 5  is a partial elevation view of the self-adjusting bolt action skewer clamp  FIG. 1  in a fully extended and locked position; and 
         FIG. 6  is a partial cross-sectional view illustrating an alternative embodiment of the present invention. 
     
    
    
     In describing the embodiment of the invention which is illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific terms so selected and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. For example, the word connected, attached, or terms similar thereto are often used. They are not limited to direct connection but include connection through other elements where such connection is recognized as being equivalent by those skilled in the art. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Specific embodiments of the present invention will be described by the following non-limiting examples which will serve to illustrate various features of the invention. With reference to the drawing figures in which like reference numerals designate like parts throughout the disclosure, a representative embodiment of the present invention is a bicycle trainer  5  that allows for stationary training on a bicycle. The bicycle trainer  5  includes a frame  9  that supports the bicycle in a stationary position while a user exerts a pedaling effort to rotate a driven wheel  11  of the bicycle during a training session, in a manner as is known, in which the rotation of the driven wheel is resisted by a resistance unit  13  that is arranged on the frame  9 . The resistance unit  13  operates in a known way and can be one of an electronic, magnetic, fluid, or airflow-type resistance units such as those incorporated into various ones of the POWERBEAM PRO, SUPERMAGNETO PRO, JETFLUID PRO, FLUID2, MAGNETO, and WIND series trainers available from CycleOps POWER of Madison, Wis. 
     Still referring to  FIG. 1 , frame  9  is generally U-shaped and includes a lower segment  15  that is connected to a bar  17  that has a pair of rear feet  19  that engage the ground or other underlying support surface. A pair of side segments  21  extends from opposing ends of the lower segment  15  of the frame  9 . The side segments  21  extend angularly from the lower segment  15  and bar  17 . A space  23  is defined between the side segments  21  and in which the driven wheel  11  is arranged during use. Legs  25  extend downwardly from upper ends  27  of the frame side segments  21 . Forward feet  29  are arranged at the lower ends  31  of the legs  25  and engage the ground or other underlying support surface. It is understood, however, that frame  9  may have any other configuration as desired. 
     Still referring to  FIG. 1 , a wheel support system  33  is arranged toward an upper portion of the frame  9  for mounting the driven wheel to the bicycle trainer  5 . Wheel support system  33  includes a support  35  which is shown in this embodiment as a tube  37  that is connected to an upper end  27  of a side segment  21  of the frame  90  so that an inner end  39  is fixed in location relative to the frame  9 . The inner end  39  of tube  37  engages and fixedly supports an end  41  of a skewer  43  that extends through and supports a hub  45  of the driven wheel  11 . An opposite end  47  of the skewer  43  is supported by a clamp  49 . In accordance with the present invention, clamp  49  is self-adjusting and actuates in a bolt action manner to secure the skewer  43  in the wheel support system  33 . 
     Referring now to  FIG. 2 , clamp  49  includes an outer tube  51  that is coaxially aligned with the tube  37  of the support  35  and is arranged on the upper end  27  of the other side segment  21 . The outer tube  51  has a circumferential side wall  52  with opposing ends  53 ,  54 . A slot  55  extends through the circumferential side wall  52  along a generally helical path. A pocket  57  extends from an inward end of the slot  55  that is closest to the driven wheel  11  ( FIG. 1 ) and provides a recess in which a handle  59  that extends through the slot  55  can lock into to secure the handle  59  in a fixed position, in a bolt-action manner. The handle  59  is connected to a carrier  61  that is in the form of a cylindrical plug that includes opposing outer and inner ends  63 ,  65  and that is arranged concentrically inside and allowed to longitudinally translate within a space  67  inside of a clamping member, which may be in the form of an inner tube  69 . The inner tube  69  is arranged concentrically inside of the outer tube  51  and is supported for siding longitudinal movement within the outer tube  51  at the opposing ends  53 ,  54  by way of bushings  53 A,  54 A. A circumferential side wall  71  of the inner tube  69  extends about the space  67 . A pin  73  extends transversely through the tube  69  and engages and retains a first end  75  of a spring  77 , which is contained within the passage defined by the inner tube  69 . A second end  79  of the spring  77  is engaged with and supported by an end surface  81  at the inner end  65  of the carrier  61 . The handle  59  extends through the slot  83  so that the carrier  61  and inner tube  69  can move relative to each other between two maximum travel positions. In one of the maximum travel positions, the inner tube  69  is fully extended with respect to the handle  59  so that the handle  59  abuts an outer end  85  of the slot  83 . In the other of the maximum travel positions, the inner tube  69  is fully retracted with respect to the handle  59  so that the handle  59  abuts an inner end  87  of the slot  83 . 
     Referring again to  FIG. 1 , in this arrangement, the clamp  49  can self-adjust the amount to which the inner tube  69  extends beyond the outer tube  51  and the clamping pressure against the skewer  43  ( FIG. 1 ). That is because the spring  77  ( FIG. 2 ) biases the inner tube  69  toward the fully extended position by pushing an inner end  89  of the inner tube  69  away from the carrier  61  ( FIG. 2 ) and toward the end  47  of the skewer  43 . The extent to which the inner tube  69  can extend toward the skewer  43  is limited by the distance between the outer tube  51  and the end  47  of the skewer  43  when the drive wheel  11  operably engages the resistance unit  13  and the end  42  skewer  43  abuts the inner end  39  of the tube  37  of the support  35 . In this regard, the inner tube  69  can extend to different positions beyond the outer tube  51  when the handle  59  is in the locked position in the pocket  57  ( FIG. 2 ), depending on the length of the skewer  43 . Regardless of the length of the skewer  43 , when the handle  59  is rotated into the locked position within the pocket  57 , the inner end  89  of the inner tube  69  automatically obtains a proper position with respect to and engagement of the end  47  of skewer  43  by compressing the spring  77  relatively further for a relatively longer skewer  43  or by compressing the spring  77  relatively less far for a relatively shorter skewer  43 . 
     Referring now to  FIGS. 3-5 , the self-adjustment of the clamp  49  is shown in a schematic representation of a sequence of rotating the handle  59  into the locked position. In  FIG. 3 , the handle  59  is in an unlocked position and the inner tube  69  is spaced from the skewer  43 . In  FIG. 4 , the handle  59  has been rotated so as to advance through the slot  55 , helically along the outer tube  51 , until the inner tube  69  first contacts the skewer  43 . At this point, the inner tube  69  is in the fully extended position with respect to the carrier  61  so that the handle  59  is shown as being at the left-most position within and abutting the end  85  of the slot  83 . In  FIG. 5 , the handle  59  has been fully rotated into the locked position in which the handle  59  is seated in the pocket  57  of slot  55 . Even though the handle  59  shown in  FIG. 5  has longitudinally advanced along the outer tube  51  when compared to the position of initial contact of the inner tube  69  and skewer  43  as shown in  FIG. 4 , and the inner tube  69  of  FIG. 5  has rotated within the outer tube  51  relative to its position in  FIG. 4 , the inner tube  69  is in the same longitudinal position with respect to the outer tube  51 . Accordingly, the handle  59  and carrier  61  have advanced relative to the inner tube  69  while moving from the positions of  FIG. 4  to those of  FIG. 5  by compressing the spring  77  to accommodate such relative movement. In this way, the clamp  49  can self-adjust to accommodate different skewers  43  of different lengths that vary in length by amounts that correspond to the length of slot  83  of the inner tube  69  so as to accommodate different size hubs  45  and driven wheels  11  of different bicycles used with the bicycle trainer  5 . 
       FIG. 6  illustrates an alternative arrangement in accordance with the present invention, in which the self-adjusting skewer clamp feature is incorporated into the stationary side of the clamping arrangement, which is shown at  135 . In this arrangement, the frame upper end  27  includes an inwardly extending post  137 . A cylindrical receiver  138  is slidably mounted over post  137 . Cylindrical receiver  138  includes an open end  140  that is configured to receive one end of a bicycle wheel skewer or axle, in a manner as is known, as well as a side wall  142 . Post  137  defines a reduced diameter outer end portion  144  that terminates in a shoulder  146 . A cap  148  is fitted over the end of reduced diameter end portion  144 , and is configured to guide the outer portion of cylindrical receiver  138  during movement on post  137 . Cap  148  may be secured to the end of reduced diameter end portion  144  in any satisfactory manner, such as by means of a screw  150  or the like. A snap ring  152  is engaged within the passage defined by cylindrical receiver  138  so as to define a stop surface, and a spring  154  is positioned between snap ring  152  and shoulder  146 . With this arrangement, spring  154  biases cylindrical receiver  138  outwardly to a position in which snap ring  152  engages the inner end surface of  148 , which is shown at  156 . When the actuator of the clamping mechanism is operated to initiate a clamping action on the bicycle skewer or axle, the end of the skewer or axle that is received by the open end  140  of cylindrical receiver  138  exerts a force on cylindrical receiver  138  in an outward direction, i.e. toward the frame  27 . This force causes outward movement of snap ring  152 , which functions to compress spring  154 . Spring  154  continues to apply an outward bias on cylindrical receiver  138  in order to provide a secure clamping force on the bicycle axle or skewer during use. When the actuator of the clamping mechanism is moved so as to relieve the clamping force on the bicycle axle or skewer, spring  154  functions to return cylindrical receiver  138  to its outwardmost most position in which snap ring  152  is engaged with end surface  156  of cap  148 . 
     It can thus be appreciated that the self-adjusting feature of the skewer or axle clamp of the present invention can be incorporated in either the actuating portion of the clamping mechanism or in the receiving portion of the clamping mechanism, or both. In addition, it can be appreciated that the self-adjusting feature of the skewer or axle clamp of the present invention may be employed with an type of actuator mechanism, and is not limited to use in combination with a bolt action-type actuator mechanism as described above. 
     Various alternatives and embodiments are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter regarded as the invention.