A delivery system for deploying a medical device, such as a stent, at increasing deployment speed is described. The system comprises a catheter comprising a catheter shaft, a retractable sheath slidably mounted on the catheter shaft, and the device in a compressed state sandwiched between the shaft and sheath. A control handle is included with a housing and knobs for a user to apply a rotary or other force to retract the sheath. The sheath is attached to a slider that is mounted on a slide rod and attached to a drive belt. A take up pulley is provided in the housing and connected to the belt input knob, so that the pulley turns when the knob is turned. The belt is attached to the pulley so that the drive is wound onto the rotating pulley. As the belt winds upon the pulley, the overall outside diameter of the pulley increases, thereby increasing the deployment speed.