Foldable bicycle and kit for making same

Claim 2

For use in a bicycle having a frame which includes a fork to which the bicycle front wheel is attached, a seat post extending from the sprocket hub to the point of attachment of the seat, and top and bottom crossbars extending between the seat post and the fork, the top and bottom crossbars being tubular in construction, a kit for altering the frame of the bicycle so the frame can be folded once the two crossbars are severed along an axis through the two crossbars, the kit including first and second upper insert pieces to be fitted into the two open ends of the top crossbar provided at the point of severance thereof, first and second lower insert pieces to be fitted into the two open ends of the bottom crossbar provided at the point of severance thereof, a first upper hinge member to be engaged with the first upper insert piece, a second upper hinge member to be engaged with the second upper insert piece, a first lower hinge member to be engaged with the first lower insert piece, a second lower hinge member to be engaged with the second lower insert piece, means for fastening the first upper hinge member to the first upper insert piece, means for fastening the second upper hinge member to the second upper insert piece, means for fastening the first lower hinge member to the first lower insert piece, means for fastening the second lower hinge member to the second lower insert piece, a rigid elongated upper crossbar piece to be extended between the first and second upper hinge members, a rigid elongated lower crossbar piece to be extended between the first and second lower hinge members, first upper fastening means for releasably securing the upper crossbar piece to the first upper hinge member, second upper fastening means for releasably securing the upper crossbar piece to the second upper hinge member, first lower fastening means for releasably securing the lower crossbar piece to the first lower hinge member, second lower fastening means for releasably securing the lower crossbar piece to the second lower hinge member, the point of connection between each crossbar piece and its cooperating hinge member providing a hinged joint which allows the bicycle frame to be releasably held in a planar position providing a standard bicycle frame, or in a folded position in which the length of the bicycle is shortened relative to its standard length.

Claim 3

Apparatus according to claim 1 including guide means to be engaged with each crossbar to mark the coaxial point of severance of the two crossbars.

Claim 4

Apparatus according to claim 2 in which the guide means includes an elongated guide frame to be engaged with each crossbar to mark the point of severance thereoF, and fastening means to be engaged with the guide frame for releasably securing the guide frame to the crossbars.

Claim 5

Apparatus according to claim 1 including cooperating detent means and receptacle means formed in the interface between each crossbar piece and its corresponding hinge members for forming said hinged joints.

Claim 6

Apparatus according to claim 4 in which the detent means are arranged so the upper crossbar section may be engaged with its cooperating hinge members to hold the hinge members at 90* angles relative to the axis of the upper crossbar section, and so the lower crossbar section may be engaged with its corresponding hinge members to hold the lower hinge members at 90* angles relative to the axis of the lower crossbar section.

Claim 7

Apparatus according to claim 1 in which the interface between each insert section and its corresponding hinge member is on an angle which is inclined relative to the axis of its respective crossbar, in which the hinge member has a smooth bore aligned with a threaded bore of its corresponding insert section, and in which the means for releasably fastening each hinge member to its corresponding insert section comprises a separate threaded fastener adapted to fit through the smooth bore and be engaged with the threaded bore so that tightening of the fastener wedges the hinge member and insert piece combination into engagement with the interior of the crossbar.

Claim 8

In a bicycle having a frame which includes a fork to which the bicycle front wheels are attached, a seat post extending from the sprocket hub to a point of attachment for the bicycle seat, and top and bottom crossbars extending between the seat post and the fork and normally being in a common plane, the top and bottom crossbars being severed to define respective front and rear sections thereof, means for folding the bicycle into a compact form comprising: first and second upper hinge members attached to the front and rear sections of the top crossbar, respectively, first and second lower hinge members attached to the front and rear sections of the lower crossbar, respectively, a rigid, elongated upper crossbar piece extending between the first and second upper hinge members, a rigid, elongated lower crossbar piece extending between the first and second lower hinge members, first upper fastening means providing a hinged joint located in the normal plane of the top crossbar for connecting one end of the first crossbar piece to the first upper hinge member, second upper fastening means providing a hinged joint located in the normal plane of the top crossbar for connecting the other end of the upper crossbar piece to the second upper hinge member, first lower fastening means providing a hinged joint located in the normal plane of the bottom crossbar for connecting one end of the lower crossbar piece to the first lower hinge member, and second lower fastening means providing a hinged joint located in the normal plane of the bottom crossbar for connecting the other end of the lower crossbar piece to the second lower hinge member, the first upper and lower fastening means being adjustable between (1) tightened positions in which they normally hold the first upper and lower hinge members in the same plane as the upper and lower crossbar pieces, respectively, and (2) loosened positions in which they allow the first upper and lower hinge members to pivot relative to the upper and lower crossbar pieces, respectively, about a first axis through the hinged joints provided by said first upper and lower fastening means, the second upper and lower fastening means being adjustable between (1) tightened positions in which they normally hold the second upper and lower hinge members in the same plane as the upper and lower crossbar pieces, respectively, and (2) loosened positions in which they allow the second upper and lower hinge members to pivot relative to the upper and lower crOssbar pieces, respectively, about a second axis through the hinged joints provided by said second upper and lower fastening means.

Claim 9

In a bicycle having a frame which includes a fork to which the bicycle front wheels are attached, a seat post extending from the sprocket hub to a point of attachment for the bicycle seat, and top and bottom crossbars extending between the seat post and the fork and normally being in a common plane, the top and bottom crossbars being severed to define respective front and rear sections thereof, means for folding the bicycle into a compact form comprising: first and second upper hinge members attached to the front and rear sections of the top crossbar, respectively, first and second lower hinge members attached to the front and rear sections of the lower crossbar, respectively, a rigid, elongated upper crossbar piece extending between the first and second upper hinge members, a rigid, elongated lower crossbar piece extending between the first and second lower hinge members, first upper fastening means providing a hinged joint located in the normal plane of the top crossbar for connecting one end of the first crossbar piece to the first upper hinge member, second upper fastening means providing a hinged joint located in the normal plane of the top crossbar for connecting the other end of the upper crossbar piece to the second upper hinge member, first lower fastening means providing a hinged joint located in the normal plane of the bottom crossbar for connecting one end of the lower crossbar piece to the first lower hinge member, and second lower fastening means providing a hinged joint located in the normal plane of the bottom crossbar for connecting the other end of the lower crossbar piece to the second lower hinge member, the first upper and lower fastening means being adjustable between (1) tightened positions in which they normally hold the first upper and lower hinge members in the same plane as the upper and lower crossbar pieces, respectively, and (2) loosened positions in which they allow the first upper and lower hinge members to pivot relative to the upper and lower crossbar pieces, respectively, about a first axis through the hinged joints provided by said first upper and lower fastening means, the second upper and lower fastening means being adjustable between (1) tightened positions in which they normally hold the second upper and lower hinge members in the same plane as the upper and lower crossbar pieces, respectively, and (2) loosened positions in which they allow the second upper and lower hinge members to pivot relative to the upper and lower crOssbar pieces, respectively, about a second axis through the hinged joints provided by said second upper and lower fastening means.

Claim 10

Apparatus according to claim 7 in which each fastening means includes cooperating detent and receptacle means formed at the interface between the end of each crossbar piece and its corresponding hinge member, the cooperating detent and receptacle means being engageable when the upper and lower crossbar pieces are aligned in a common plane with their respective hinge members.

Claim 11

Apparatus according to claim 8 in which the detent and receptacle means corresponding to the first upper and lower hinge members also are releasably engageable when the first upper and lower hinge members are folded to an angle of about 90* relative to the plane of the upper and lower crossbar pieces, and in which the detent and receptacle means corresponding to the second upper and lower hinge members also are releasably engageable when the second upper and lower hinge members are folded to an angle of about 90* relative to the plane of the upper and lower crossbar pieces, and in which each fastening means also includes a separate fastener to be tightened for rigidly holding the respective upper and lower hinge members in their folded positions at 90* angles relative to the plane of the upper and lower crossbar pieces.

Claim 12

Apparatus according to claim 7 in which each fastening means includes at least four radially spaced apart, releasably engageable detent and receptacle means formed at the interface between the end of each crossbar piece and its corresponding hinge member, and a separate fastener at each interface extending centrally through its corresponding detent and receptacle means for being tightened to hold the detent and receptacle means rigidly in engagement or to be loosened to allow the detent and receptacle means to be released from engagement and folded with respect to each other through an angle of about 90* for further rigid engagement by tightening of the fasteners.

Claim 13

Apparatus according to claim 10 in which the hinge members and the crossbar pieces are generally rounded to match the outer contour of the front and rear crossbar sections.

Claim 14

Apparatus according to claim 11 in which the fasteners are countersunk to avoid protruding parts.

Claim 15

Apparatus according to claim 7 in which the front and rear sections of the top and bottom crossbars are tubular, and further including first and second upper insert pieces fitted into the two open ends of the front and rear sections of the top crossbar, respectively, first and second lower insert pieces fitted into the two open ends of the front and rear sections of the bottom crossbars, respectively, means for fastening the first and second upper hinge members to the first and second upper insert pieces, respectively, and means for fastening the first and second lower hinge members to the first and second lower insert pieces, respectively, such that the upper hinge members extend from the ends of the front and rear sections of the top crossbar and the lower hinge members extend from the ends of the front and rear sections of the lower crossbar for attachment to their respective crossbar pieces.