Patent attributes
A suction valve for an endoscope use includes a valve casing which is set up in the control portion of an endoscope and is connected with a suction side path having an opening as a suction inlet at the tip distal end of the insertion portion of the endoscope and is also connected with a suction source side path connected with a negative pressure generation source, and a valve member which is fitted up in the valve casing to be allowed to make a slide motion inside thereof and is constituted such that it is able to switch the state in which the suction side path is cut off from the suction source side path to the state in which the suction side path is in communication with the suction source side path or vice versa in correspondence with the position of the valve member in the valve casing, wherein a groove is formed in the outer peripheral surface of the valve member in contact with the inside of the valve casing. With this, foreign substances for instance body fluids and others sticking to a gap between the valve casing and the valve member are driven into the groove formed in the outer peripheral surface of the valve member by the slide motion of the valve member, thus the slide friction being prevented from increasing and further, enabling the suction switching control to be carried out stably and smoothly.
