Adjustable seat for bicycle, exercise machine or the like

An adjustable seat, comprising:

• a seat frame comprising a first seat body and a second seat body spaced apart each other to define an adjustment channel between said first and second seat bodies;
• and
• an adjustable assembly supported underneath said seat frame and configured to selectively adjust a distance between said first and second seat bodies, wherein said adjustable assembly comprises:
• a retention frame configured to support said seat frame thereon for mounting said adjustable seat to the bicycle, exercise machine and the like;
• a first adjustable member and a second adjustable member coupled at said first seat body and said second seat body respectively and aligned with each other;
• an adjustor arranged underneath said seat frame and to be driven to rotate at a rotatable direction along a centerline of said adjustable channel to selectively adjust a width of said adjustment channel so as to adjust the distance between said first seat body and said second seat body;
• a transmission mechanism arranged between said retention frame and said seat frame, wherein said adjustor is incorporated with said first adjustable member and said second adjustable member to transmit a rotation movement of said adjustor to a linear movement to selectively drive said first adjustable member and said second adjustable member to move towards or apart each other between a compact mode and an extension mode of the seat frame, wherein in the compact mode, the distance between said first seat body and said second seat body is minimized, and in the extension mode, the distance between said first seat body and said second seat body is maximized;
• and
• a guiding device supported between said first and second adjustable members and said retention frame and incorporated with said transmission mechanism to guide movement of said first adjustable member and said second adjustable member along a predetermined path between the compact mode and the extension mode.