Bicycle frame with reinforced motor mount

The present invention provides a bicycle comprising a motor mounted to a motor mount of the bicycle frame. The motor mount includes a down tube mount coupled to a down tube, a chainstay mount coupled to a chainstay, and a side brace secured to the down tube mount and wrapping around one side of the motor to the chainstay mount. Preferably, when viewed from the side, the side brace extends directly from the down tube mount to the chainstay mount. Preferably, the motor mount further comprises a lower support secured to the down tube mount and wrapped around a bottom of the motor to the chainstay mount. The motor mount can further include an upper support connecting the seat tube mount to the down tube mount. This upper support can include an upper flange secured to the motor.

BACKGROUND

The present invention relates to bicycle frames and specifically to a bicycle frame that is adapted to support an electric motor.

It is known to provide a bicycle with an electric motor and battery in order to supplement the pedaling power provided by the user. Such electric motors can be secured to or incorporated into the bicycle frame or wheel hubs.

SUMMARY

The present invention provides a bicycle comprising a front wheel and a rear wheel cooperatively defining a central plane and forward and rearward directions, a front fork supported by the front wheel, and a frame supported by the front fork and the rear wheel. The frame includes a head tube rotationally coupled to the front fork, a down tube extending downward and rearward from the head tube, a motor mount coupled to and extending from the down tube, and a chainstay coupled between the motor mount and the rear wheel. A motor is mounted to the motor mount. The motor mount includes a down tube mount coupled to the down tube, a chainstay mount (e.g., a pivot mount) coupled to the chainstay, and a side brace secured to the down tube mount and wrapping around one side of the motor to the chainstay mount. A side of the motor mount opposite the side brace includes an opening large enough to facilitate insertion and removal of the motor. Preferably, when viewed from the side, the side brace extends directly from the down tube mount to the pivot mount.

Preferably, the motor mount further comprises a lower support secured to the down tube mount and wrapped around a bottom of the motor to the chainstay mount. For example, the lower support can be substantially aligned with the central plane. In one embodiment, the lower support comprises a lower flange secured to the motor.

The frame can further include a seat tube, and the motor mount can further include a seat tube mount coupled to the seat tube. Preferably, the motor mount further includes an upper support connecting the seat tube mount to the down tube mount. This upper support can include an upper flange secured to the motor. The motor mount can further include a rear support connecting the seat tube mount to the chainstay mount.

DETAILED DESCRIPTION

FIGS. 1-3illustrate a bicycle20embodying the present invention. The illustrated bicycle20includes a front wheel22and a rear wheel24that cooperatively define a central plane26and forward and rearward directions. A front fork28is supported by the front wheel22, and a frame30is supported by the front fork28and the rear wheel24. The illustrated frame30includes a head tube32rotationally coupled to the front fork28, a down tube34extending downward and rearward from the head tube32, a top tube36extending rearward from the head tube32, a seat tube38extending downward from the top tube36, and a motor mount40connecting the down tube34and the seat tube38. The frame30further comprises a rear suspension assembly42including chainstays44, rear wheel mounts46, seat stays48, and a rear shock50, the functions of which are well known in the art.

The illustrated bicycle20further includes an electric motor52adapted to provide power to the bicycle20. The illustrated electric motor52includes three mounting studs54for securing the electric motor52to the frame30via mounting nuts55. The electric motor52further includes a drive shaft56connected to left and right cranks58that are adapted to receive corresponding pedals59that facilitate pedaling of the bicycle20by a user. Power is provided to the electric motor52via a battery60mounted within a tube recess62in the down tube34, as explained below in more detail.

As best seen inFIG. 4, the motor mount40includes a down tube mount64coupled to the down tube34, a seat tube mount66coupled to the seat tube38, and a chainstay mount68coupled to the chainstays44. The illustrated down tube mount64and seat tube mount66are welded to the down tube34and seat tube38, respectively, but any suitable connection (e.g., bonding, fastening, or unitary construction) will suffice. The illustrated chainstay mount68comprises a pivot mount70for pivotally connecting the motor mount40to the chainstays44using a pivot shaft72.

The motor mount40further includes a side brace74connecting the down tube mount64to the chainstay mount68along the left side of the electric motor52. As best shown inFIGS. 3-4, the side brace74is positioned to structurally and visually extend from the down tube34directly toward the chainstay mount68. As shown inFIG. 5, the right side of the motor mount40does not include a side brace74and is completely open to facilitate insertion and removal of the electric motor52from the motor mount40.

Referring toFIGS. 3 and 4, the motor mount40further includes an upper support76connecting the down tube mount64with the seat tube mount66, a rear support78connecting the seat tube mount66with the chainstay mount68, and a lower support80connecting the down tube mount64with the chainstay mount68. As illustrated inFIGS. 3, 4, and 6, the upper support76includes an upper flange82aligned with the central plane26and including a flange opening84adapted to receive one of the mounting studs54in order to facilitate attachment of the electric motor52to the motor mount40by the mounting nuts55. Similarly, the lower support80includes a lower flange85aligned with the central plane26and including two flange openings84adapted to receive two of the mounting studs54in order to facilitate attachment of the electric motor52to the motor mount40. As explained above and illustrated in the drawings, the combination of the down tube mount64, the upper support76the seat tube mount66, the rear support78, the chainstay mount68, and the lower support80provides complete enclosure of the electric motor52along the central plane26of the bicycle20. This arrangement provides structural integrity to the bicycle frame30and also helps to protect the electric motor52from damage that could be caused by impact of the bicycle20with other objects (e.g., rocks or logs). This arrangement also utilizes the electric motor52as a stressed member to further improve the strength and rigidity of the bicycle frame30.

As illustrated inFIGS. 3-5and further explained above, the structural arrangement of the motor mount40results in an upper left opening86, a lower left opening88, and a right opening90. These openings are fitted with an upper left cover92, a lower left cover94and a right cover96, respectively. Each of the upper support76, lower support80, and rear support78includes threaded openings98for receiving threaded fasteners100that attach the covers to the motor mount40. The covers protect the electric motor52from damage and debris infiltrating the electric motor52.

Referring toFIG. 3, the illustrated battery60includes an upper battery mount102and a lower battery mount104that facilitates securing the battery60to the bicycle frame30at an upper frame mount106and a lower frame mount108, respectively. When attaching the battery60to the frame30, the lower battery mount104is first engaged with the lower frame mount108with the battery60in a partially attached position, as shown inFIG. 7. The battery60is then pivoted upwardly toward the frame30to a fully attached position, as shown inFIG. 8and described below in more detail.

The lower battery mount104and lower frame mount108define a pivot interface between the battery60and the frame30. In the illustrated embodiment, the lower battery mount104comprises an eccentric boss110adapted to engage the lower frame mount108. In the embodiment shown inFIGS. 9 and 10, the eccentric boss110comprises an elongated shaft having a cam profile with a low point112defining a first boss width W1and a high point114defining a second boss width W2larger than the first boss width. As the battery60is pivoted from the partially attached position ofFIG. 7to the fully attached position ofFIG. 8, the cam profile of the eccentric boss110will be rotated with the battery60to present different profiles of the eccentric boss110to the lower frame mount108, as described below in more detail.

The illustrated lower frame mount108defines a depression in the form of a slot116that is dimensioned to receive the eccentric boss110. With specific reference toFIGS. 9 and 10, the slot116has a width that is dimensioned to easily receive the first boss width W1of the eccentric boss110. This is the orientation of the eccentric boss110that will be presented to the lower frame mount108when the battery60is in the partially attached position ofFIGS. 7 and 9. As the battery60is rotated to the fully attached position, the cam profile of the eccentric boss110is rotated such that the second boss width W2of the eccentric boss110is presented to the slot116of the lower frame mount108, thereby wedging the eccentric boss110in the lower frame mount108, as shown inFIGS. 8 and 10. In order to facilitate this interference fit, the lower frame mount108is resilient (e.g., made from a resilient material such as polyurethane or resiliently mounted, such as spring-biased). By virtue of this arrangement, the lower battery mount104will be held securely to the lower frame mount108with reduced likelihood of any rattling occurring due to shocks or vibrations. In addition, the resilient slot116configuration of the lower frame mount108will inherently accommodate slight differences in battery60lengths. It should be understood that the positions of the eccentric boss110and depression could be reversed (i.e., the depression could be positioned on the battery60and the eccentric boss110could be positioned on the frame30). In addition, the eccentric boss110could be made of a resilient material instead of or in addition to the lower frame mount108.

As best seen inFIGS. 7-8 and 11-12, the upper battery mount102comprises a battery hole118extending all the way through the battery60, and the upper frame mount106includes tube holes120through the left and right walls of the down tube34adjacent an upper end of the tube recess62. With the battery60in the fully attached position ofFIG. 8, the battery hole118of the upper battery mount102will be aligned with the tube holes120of the upper frame mount106, and a battery mounting pin122can be inserted through the aligned tube holes120and battery hole118to secure the battery60in the fully attached position. In the illustrated embodiment, one of the tube holes120is threaded and an end of the battery mounting pin122is similarly threaded to secure the mounting pin in place.

With specific reference toFIGS. 3, 7 and 8, the illustrated bicycle20further includes a rock guard124secured to and removable from a lower end of the battery60. The rock guard124includes a forked end126adapted to fit on opposing sides of the lower battery mount104. In the illustrated embodiment, the forked end126of the rock guard124is secured to the battery60by the same battery fastener128that secures the eccentric boss110to the battery60, as best shown inFIG. 3. The rock guard124further includes two threaded openings (not shown) facing the battery60and adapted to receive fasteners (not shown) that can be inserted through holes in the battery60and threaded into the threaded openings98in the rock guard124to further secure the rock guard124to the battery30. By virtue of this arrangement, the rock guard124provides protection to the lower end of the battery60and can be easily replaced if damaged.

The battery60further includes a battery control panel130that facilitates control of the operation of the battery60, best seen inFIG. 13. Specifically, the battery control panel130includes a power button132, a plus button134and a minus button136. These buttons can be used to power the battery60on and off and also to select different modes of the battery60. The battery control panel130further includes a series of perimeter lights138that indicate the battery charge.

Referring toFIG. 14, the battery60further includes a battery connector140on the left side of the battery60near the lower battery mount104. The illustrated battery connector140can be used both to charge the battery60(e.g., with an appropriate charger, not shown) and also to provide connection to the electric motor52via a motor connector142wired to the electric motor52. The illustrated motor connector142includes an overmolded housing144that fits into and is flush with the surrounding surfaces.

The illustrated bicycle20further includes a speed sensor146secured to an inner face148of the left rear wheel24support, as illustrated inFIG. 15. The speed sensor senses the rotation of the rear wheel24, and this information can be used to calculate the speed of the bicycle20. By virtue of this positioning, the speed sensor146is protected from damage and is further not visible from the left side of the bicycle20, thus improving aesthetics of the bicycle20.

Referring toFIG. 16, the inside surface of the right cover96includes an integral cable channel150that facilities routing of a cable through the motor mount40. More specifically, with the right cover96secured to the motor mount40, the cable channel150will be positioned against the electric motor52, thereby creating a substantially enclosed passageway. With this substantially enclosed passage way, a cable or housing can be inserted into the passage way from the down tube34(see arrows inFIG. 16) and pushed until it exits adjacent the chainstay mount. This arrangement avoids the need to remove the right cover96when threading a new cable or housing through the motor mount40.