Adjustable cycle-type seat post assembly

An adjustable seat post assembly comprising:

• a tubular seat adapted to fit slidably within a tubular seat mast of a cycle-type apparatus, the seat post having a cylindrical bore with a closed upper end and an open lower end;
• a mounting shaft having piston means at the upper end telescopically fitted within the cylindrical bore and defining with the closed upper end of the cylindrical bore a variable volume air chamber;
• air sealing means acting between the piston means and the cylindrical bore;
• a plurality of axially spaced fastening means at the lower end of the mounting shaft for removably securing it in a selected axial position relative to a securing member carried within a tubular seat mast;
• and
• valve means at the upper end of the seat post for introducing pressurized air into the air chamber.

An adjustable seat post assembly comprising:

• a tubular seat post adapted to fit slidably within a tubular seat mast of a cycle-type apparatus, the seat post having a cylindrical bore with a closed upper end and an open lower end;
• a mounting shaft having an elongated body with an upper head portion, an intermediate portion, and a lower head portion;
• the upper head portion including piston means telescopically fitted within the cylindrical bore and defining with the closed upper end of the cylindrical bore a variable volume air chamber:
• air sealing means acting between the piston means and the cylindrical bore;
• the intermediate portion having an axially extending slot engaged with a pin carried by the seat post to limit relative axial movement between the seat post and mounting shaft, and to prevent relative torsional movement therebetween;
• the lower head portion including aperture means comprising a plurality of openings spaced apart along the length of the mounting shaft and being selectively engageable with a member carried by a seat mast to secure the mounting shaft at a selected axial position therein;
• and
• valve means at the upper end of the seat post for introducing pressurized air into the air chamber.

An adjustable seat post assembly comprising:

• a tubular seat post adapted to fit slidably within a tubular seat mast of a cycle-type apparatus, the seat post having a cylindrical bore with a closed upper end and an open lower end;
• a mounting shaft having an elongated body with an upper head portion, an intermediate portion, and a lower head portion;
• the upper head portion including piston means telescopically fitted within the cylindrical bore and defining with the closed upper end of the cylindrical bore a variable volume air chamber;
• air sealing means acting between the piston means and the cylindrical bore;
• the intermediate portion having an axially extending slot engaged with a pin carried by the seat post to limit relative axial movement between the seat post and mounting shaft, and to prevent relative torsional movement therebetween;
• the lower head portion including aperture means engageable with a member carried by a seat mast to secure the mounting shaft therein;
• said aperture means being formed in a recessed surface in the lower head portion to facilitate aligning said aperture means with a securing member in a tubular seat mast when assembling the mounting shaft therein;
• and
• valve means at the upper end of the seat post for introducing pressurized air into the air chamber.