US 5,397,144 A · Bicycle operated air pump

Abstract

An air pump for use with a chain-driven bicycle having a free wheel. The pump assembly comprises a pair of opposed cylinders and a double-ended piston rod mounted in a housing. The piston rod has a bearing slot, which engages a crank pin on a crankshaft driven by a sprocket. Rotation of the sprocket reciprocates the double-ended piston rod in the cylinders. The cylinders are each integrally formed with a manifold that uses an elastomeric band covering a passage from the cylinder interior to inside the manifold as a one-way valve. An enlarged diameter skirt on each cylinder allows air to enter the cylinder on each intake stroke. A cap defining the piston head is locked onto each piston and holds a seal in place on the piston. An integral clamp assembly allows the pump to be removably mounted on a bicycle chain stay. The lower run of the bicycle drive chain engages the drive sprocket of the pump assembly, and a chain retainer is used to maintain the engagement of the drive chain with the drive sprocket. Reverse rotation of the bicycle's crank assembly causes the conventional free wheel to also rotate in a reverse direction without rotating the wheel of the bicycle. The resulting movement of the chain over the drive sprocket of the pump rotates the drive sprocket, which reciprocates the double-ended piston rod in the cylinders, and pumps air to an article to be inflated, such as the bicycle tire(s).

Claims32

Dependent claims

A method for pumping air using a bicycle having a frame, a crank assembly rotatably mounted to said frame, a wheel rotatably mounted to said frame, a free wheel gear cluster attached to said wheel for rotating said wheel when said gear cluster is caused to rotate in a forward direction and for rotating independently of said wheel when said gear cluster is rotated in a reverse direction, and a drive chain having upper and lower chain runs interconnecting said crank assembly and said free wheel gear cluster and extending along upper and lower paths, respectively, said method comprising the steps of:

(a) providing an air pump having a housing that includes a drive sprocket and pumping means for pumping air in response to rotation of said drive sprocket;
(b) positioning said air pump proximate said drive chain so that said air pump is stationary relative to said bicycle;
(c) moving a selected one of said upper and lower runs of said drive chain substantially away from its respective path and engaging said selected one of said runs with said drive sprocket;
(d) maintaining the engagement of said drive chain with said drive sprocket with a chain retainer mounted to said drive sprocket;
and
(e) rotating said crank assembly and said free wheel gear cluster in a reverse direction so that said selected one of said runs moves past said drive sprocket so as to rotate said drive sprocket, whereby said pumping means of said stationary air pump is operated while said wheel of said bicycle remains stationary.

3 more elements

An air pump designed for use with a bicycle having a frame, a first elongate tube, a wheel rotatably mounted to the frame, a crank assembly rotatably mounted to the frame, at least one gear attached to the wheel, the at least one gear being designed to cause the wheel to rotate in a first direction when the gear is driven in the first direction, a drive chain having a length and tension selected so that the chain engages and couples the crank assembly with the at least one gear so as to transmit rotational drive from the crank assembly to the at least one gear when the crank assembly is caused to rotate, the drive chain including first and second runs extending along upper and lower paths, respectively, disposed adjacent the first elongate tube, the air pump comprising:

(a) a housing having a hollow interior;
(b) clamp means mounted to said housing, for releasably securing said housing to a selected portion of the first tube so as to permit said housing to be quickly secured to and quickly detached from the first tube;
(c) a sprocket rotatably mounted to said housing in a fixed, predetermined spaced-apart relation to said clamp means, said sprocket being adapted to engage and be rotatably driven by the drive chain, wherein said sprocket is sized and said predetermined spaced-apart relation is selected so that when said housing is secured to the first tube and one of the first and second runs of the chain is engaged with said sprocket, said one run of chain will be deflected from its respective path to an extent sufficient to increase the tension in the chain such that said one run is maintained in driving engagement with said sprocket when the chain is driven by the crank assembly;
(d) a chain retainer centrally mounted to the sprocket, sized to maintain the chain in driving engagement with said sprocket;
and
(e) pump means, positioned in said interior of said housing and coupled with said sprocket, for providing compressed air in response to rotation of said sprocket.

3 more elements

Dependencies are inferred from the claim text.

Bicycle operated air pump

Life of this patent

Bicycle operated air pump

Life of this patent

Abstract

Claims32