Patent ID: 7998058

Claim:
An endoscope system comprising: an endoscope comprising an elongated flexible insertion tube having a distal end accommodating therein at least an imaging optical system and having a flexibly bendable section juxtaposed to the distal end, the insertion tube being inserted into an object being examined; a medical instrument used in combination with the endoscope and inserted into the object through the insertion tube inserted into the object, the medical instrument having a therapeutic member; an operating unit manually operated by an operator to command both an inserting and pulling-out operation of the medical instrument and a therapeutic operation of the therapeutic member of the medical instrument; a first drive unit configured to drive the medical instrument to perform the inserting and pulling-out operation thereof in response to an operator's operation performed with the operating unit; a second drive unit configured to drive the medical instrument to perform the therapeutic operation of the therapeutic member in response to a further operator's operation performed with the operating unit; and a control unit configured to control drive characteristics of the first and second drive units based on a bent state of the bendable section, wherein the medical instrument has a tubular portion which is moved by a force applied by the first drive unit; the therapeutic member is connected to a distal end of the tubular portion; the insertion tube has a tubular channel through which the tubular portion of the medical instrument is inserted so as to make the therapeutic member protrude from a distal end of the insertion tube; and the control unit comprises: operated-state detecting means for detecting the operator's operating state at the operating unit, bent-state detecting means for detecting the bent state of the bendable section, control means for controlling the drive characteristics of the first and second drive units in accordance with the operator's operating state detected by the operated-state detecting means, and correction means for correcting a driven state of at least one of the first and second drive units depending on the bent state of the bendable section detected by the bent-state detecting means; wherein the correction means is configured to correct the force being applied to the tubular portion of the medical instrument by the first drive unit in accordance with the bent state of the bendable section detected by the bent-state detecting means such that the tubular portion is moved at a constant speed regardless of the bent state of the bendable section.