Abstract:
A bicycle trainer includes a base frame, a damper unit pivotally connected to the base frame and including a rotating wheel set, a swivel frame pivoted to the base frame and biasable between an inclined position where the swivel frame and the damper unit are capable of supporting a bicycle wheel and a collapsed position where the swivel frame is received in the base frame and the rotating wheel set of the damper unit is disposed adjacent to the swivel frame, and a locking device for locking the damper unit to the base frame or allowing the damper unit to be biased relative to the base frame. Thus, the composition of the invention allows the bicycle trainer to be folded up and received in a compact condition to minimize the dimension convenient for carrying with less effort.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to bicycle training technology and more particularly, to a bicycle trainer, which allows change of the position of the damper unit. 
     2. Description of the Related Art 
     In order for bicycle riders to exercise cycling without being affected by weather or the environment, the most common way is to set up the bike on a bicycle trainer, enabling the bike to be pedaled indoors to achieve a training effect similar to riding a bike outdoors. 
     A conventional bicycle trainer, as illustrated in U.S. Pat. No. 6,945,916 (hereinafter called as Patent 916), mainly comprises a U-shaped frame 2 and two legs 3. The legs 3 can be extended out of the bottom side of the U-shaped frame 2 to allow the bicycle trainer to be positioned on the floor. A rear wheel 9 of a bicycle 8 is held in place between two side bars of the U-shaped frame 2, and kept in contact with an impeller unit 100 that provides a damping resistance to achieve training effects. Further, the U-shaped frame 2 and the legs 3 can be folded up to allow the bicycle trainer to be easily stored. 
     Further, U.S. Pat. No. 6,780,143 (hereinafter called as Patent 143) discloses another design of bicycle trainer, wherein first and second frame members 18, 20 are pivotally connected to each other so that when the second frame member 20 is positioned on the floor, the first frame member 18 can be moved to an operative extended “up” position with respect to the second frame member 20, allowing a rear wheel 38 of a bicycle to be placed between two arcuate end portions 36 of the first frame member 18. When a user rides the bicycle, the body weight of the user and the weight of the bicycle itself can force the wheel-rotating unit 44 and the rear wheel 38 into engagement with each other for cycling exercises. 
     The impeller unit 100 or wheel-rotating unit 44 used in the aforesaid Patent 916, 143 or other similar trainer for imparting a damping resistance is fixedly mounted in one lateral side of the trainer. When the U-shaped frame or the first and second frame members are collapsed, the impeller unit 100 or wheel-rotating unit 44 is still kept projecting out of the framework, and thus the trainer storage space must be relatively increased or adjusted for smooth accommodation of the collapsed bicycle trainer. 
     Further, the impeller unit 100 or wheel-rotating unit 44 uses a heavy wheel or magnetoresistive component to impart a damping resistance. The arrangement of this heavy wheel or magnetoresistive component will shift the center of gravity away from the structural center of the framework of the trainer. When moving the trainer, the applied force cannot be evenly distributed through the framework of the trainer, causing the user unable to carry the trainer stably and safely. 
     SUMMARY OF THE INVENTION 
     The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a bicycle trainer, which has a compact structure after folded up, enhancing carrying convenience and safety. 
     To achieve this and other objects of the present invention, a bicycle trainer of the invention comprises a base frame, a damper unit, a swivel frame, and a locking device. The damper unit comprises a rotating wheel set. Further, the damper unit is pivotally mounted at the base frame, and biasable to change the position of the rotating wheel set relative to the base frame. The swivel frame is pivotally mounted at the base frame, and biasable relative to the base frame between an inclined position where the swivel frame and the damper unit are capable of supporting a bicycle wheel, and a collapsed position where the swivel frame is received in the base frame and the rotating wheel set of the damper unit is disposed adjacent to the swivel frame. The locking device is adapted for locking the damper unit to the base frame, or allowing the damper unit to be biased relative to the base frame. Thus, the bicycle trainer is kept compact when collapsed, minimizing the overall dimension and changing the position or angle of the heavy damper unit. Therefore, the invention allows the rotating wheel set to be shifted into alignment with the center of gravity of the base frame, enabling the user to carry and deliver the collapsed bicycle trainer more conveniently with less effort. 
     In one embodiment of the present invention, the damper unit comprises a body and a carrier, wherein the body comprises a first positioning portion. The carrier comprises a shaft. The body is mounted at the base frame. The shaft is pivotally connected to the first positioning portion. The carrier is rotatable on the shaft relative to the base frame. 
     In another embodiment of the present invention, the damper unit comprises a body and a carrier. The carrier is pivotally connected to the body. The locking device comprises a mounting member and a lock pin. The mounting member is mounted at the body. The lock pin is movably mounted in the mounting member. The mounting member has mounted therein a spring member that imparts a pressure to the lock pin to move the lock pin in direction toward the carrier. Thus, the lock pin can be locked to the carrier, or moved away from the carrier. 
     Other advantages and features of the present invention will be fully understood by reference to the following specification in conjunction with the accompanying drawings, in which like reference signs denote like components of structure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an oblique top elevational view of a bicycle trainer in accordance with a first embodiment of the present invention, illustrating a swivel frame in an inclined position relative to a base frame. 
         FIG. 2  is an exploded view of the bicycle trainer in accordance with the first embodiment of the present invention. 
         FIGS. 3 and 4  are sectional views taken along line  3 - 3  of  FIG. 1 , illustrating a locking position and unlocking position, respectively. 
         FIG. 5  is a side view of the first embodiment of the present invention, illustrating the carrier biased to the collapsed condition. 
         FIG. 6  is an oblique top elevational view of a bicycle trainer in accordance with a second embodiment of the present invention. 
         FIG. 7  is an exploded view of the bicycle trainer in accordance with the second embodiment of the present invention. 
         FIG. 8  is a sectional view taken along line  8 - 8  of  FIG. 6 . 
         FIG. 9  is another oblique top elevational view of the second embodiment of the present invention, illustrating the bicycle trainer collapsed. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Prior to viewing the following specification in conjunction with the accompanying drawings, it is to be understood that the bicycle trainer of the present invention can be used for bike pedaling training exercises, or simply for supporting a bicycle. Further, the directional terms or similar terms to describe the shape, or the direction such as “front”, “rear”, “top”, “bottom”, etc. throughout the specification are simply exemplary directional description languages, not intended for use to limit the scope of the claims. 
     Referring to  FIG. 1 , a bicycle trainer  10  in accordance with a first embodiment of the present invention is shown. The bicycle trainer  10  comprises a base frame  20 , a swivel frame  30 , a damper unit  40 , and a locking device  50 . The base frame  20  comprises two parallel extension bars  21 . Each extension bar  21  has opposing first end  22  and second end  23 . The swivel frame  30  is pivotally connected between the first ends  22  of the two extension bars  21 . The damper unit  40  is mounted between the second ends  23  of the two extension bars  21 . The swivel frame  30  and the damper unit  40  are respectively located at the base frame  20  at two opposite sides. The swivel frame  30  comprises two support bars  32 . The swivel frame  30  can be biased relative to the base frame  20  between an inclined position where the support bars  32  are obliquely lifted from the base frame  20  (see  FIG. 1 ), and a collapsed position where the support bars  32  are received in the base frame  20  between the two extension bars  21  (see  FIG. 9 ). 
     Referring to  FIGS. 2 and 3 , the damper unit  40  comprises a body  41  and a carrier  42 . The body  41  comprises a first positioning portion  43  for holding the carrier  42 . In this embodiment, the first positioning portion  43  is a recessed hole inwardly curved from the top wall of the body  41 . However, this design recessed hole is simply an exemplar. The carrier  42  comprises a shaft  44  located at the center. Further, the carrier  42  has mounted therein a rotating wheel set  45  and a contact wheel  46 . The rotating wheel set  45  is disposed in one lateral side of the carrier  42  and kept away from shaft  44 . The contact wheel  46  is disposed to face toward the shaft  44  for rotating the rotating wheel set  45  in the carrier  42 . The shaft  44  of the carrier  42  is coupled to the first positioning portion  43  of the body  41  by a socket  47 , and can be rotated on the shaft  44  of the carrier  42  relative to the base frame  20 . The shaft  44  comprises a plurality of locating portions  48  equally spaced around the shaft  44  at a predetermined distance or angle. 
     The second ends  23  of the two extension bars  21  of the base frame  20  are respectively connected to two opposite ends of the first positioning portion  43  of the body  41 , holding the first positioning portion  43  at the midpoint between the two extension bars  21  in an inclined position toward the swivel frame  30 . The body  41  further comprises a second positioning portion  49  adapted for holding the locking device  50 . In this embodiment, the second positioning portion  49  is a through hole extending from the periphery of the body  41  to the first positioning portion  43 . 
     The locking device  50  in this first embodiment is mounted in the damper unit  40 . However, this mounting arrangement is not a limitation. Any mounting arrangement of the locking device for enabling the carrier  42  of the damper unit  40  to be selectively locked to or rotatable relative to the base frame  20  should be included in the scope of the present invention. The locking device  50  comprises amounting member  51  and a lock pin  52 . The mounting member  51  defines therein a passage hole  53 . The lock pin  52  is mounted in the passage hole  53  of the mounting member  51 , and movable relative to the mounting member  51  between a locking position (see  FIG. 3 ) and an unlocking position (see  FIG. 4 ). A spring member  54  is mounted in the mounting member  51  around the lock pin  52 , and adapted to impart an elastic restoring force to the lock pin  52  to move the lock pin  52  in direction toward the locking position. The mounting member  51  is threaded into the second positioning portion  49  of the body  41 . The lock pin  52  has a bottom end thereof face toward the first positioning portion  43  of the body  41  so that the lock pin  52  can be inserted through the socket  47  into one locating portion  48  of the shaft  44  of the carrier  42 . Further, the lock pin  52  has a head  55  located at an opposing top end thereof for the holding of the user&#39;s hand. 
     When mounting a bicycle on the bicycle trainer of the above-described first embodiment of the present invention, the user can pull out the lock pin  52  of the locking device  50  to unlock the carrier  42  of the damper unit  40 , and then rotate the carrier  42  to the angular position shown in  FIG. 1 , i.e., to move the rotating wheel set  45  to one lateral side relative to the base frame  20  and to keep the contact wheel  46  facing toward the swivel frame  30 . At this time, the user can release the hand from the lock pin  52 , enabling the lock pin  52  to be forced by the spring member  54  into the locating portion  48  of the shaft  44  to stop the shaft  44  from rotation relative to the body  41 , and thus, the carrier  42  is locked. At this time, the bicycle wheel can be supported between the two support bars  32 , enabling the tread of the bicycle wheel to be rotatably abutted at the contact wheel  46  of the damper unit  40 . 
     When going to collapse the bicycled trainer after removal of the bicycle wheel from the swivel frame  30 , the user can pull out the lock pin  52  of the locking device  50  again to disengage the bottom end of the lock pin  52  from the shaft  44 , and then rotate the carrier  42  of the damper unit  40  to the angular position shown in  FIG. 5 , moving the rotating wheel set  45  to the midpoint of the base frame  20  beneath the damper unit  40 . Thereafter, the user can release the hand from the lock pin  52 , enabling the lock pin  52  to be forced back b y the spring member  54  to lock the carrier  42  again, prohibiting the carrier  42  from rotation relative to the base frame  20 . When the swivel frame  30  is biased to the collapsed position and received in the base frame  20 , the two support bars  32  are kept at two opposite lateral sides of the damper unit  40  near the rotating wheel set  45 . 
     When the trainer is collapsed as stated above, the swivel frame is received in the base frame, and the rotating wheel set of the damper unit is shifted to the position between the two support bars, keeping the bicycle trainer in a flat condition. Thus, the bicycle trainer is kept compact when collapsed, minimizing the overall dimension and changing the position or angle of the heavy damper unit, and thus, the rotating wheel set can be shifted into alignment with the center of gravity of the base frame, allowing the user to carry and deliver the collapsed bicycle trainer more conveniently with less effort. 
     Referring to  FIGS. 7-9 , a bicycle trainer  60  in accordance with a second embodiment of the present invention is shown. This second embodiment is substantially similar to the aforesaid first embodiment with the exception that the body  62  comprises a holding-down portion  63  extending around the first positioning portion  67 . The holding-down portion  63  has a plurality of slits  64  that enhances the elastic deformability of the holding-down portion  63 . After the shaft  66  of the carrier  65  is mounted in the first positioning portion  67 , the holding-down portion  63  surrounds the shaft  66 , a ring member  68  is threaded onto the body  62  in a coaxial manner relative to the first positioning portion  67  to press the inner perimeter thereof onto the holding-down portion  63  and the shaft  66 , holding the holding-down portion  63  in between the shaft  66  and the ring member  68 . At this time, the user can rotate the ring member  68  along the body  62  to control the contact tightness between the holding-down portion  63  and the shaft  66 . If the ring member  68  is rotated to the position where the holding-down portion  63  is elastically deformed and compressed, the shaft  66  is constrained by the ring member  68  and the holding-down portion  63  and prohibited from rotation to lock the damper unit. If the ring member  68  is rotated to the position where the ring member  68  is kept away from the holding-down portion  63 , the shaft  66  is released from the constraint of the holding-down portion  63  for free rotation, and the damper unit can be biased to the desired position or angle, and thus, this second embodiment achieves the same effects and object of the aforesaid first embodiment. 
     Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.