| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a suction operation valve for an ultrasonic endoscope which can switch a suction state from a channel suction aperture to a suction state from a balloon suction aperture by only a pushing operation of an operation button, does not often develop an operational fault, or the like, since the structure is simple, and does not develop a suction leak from the balloon suction aperture side when the operation to suck from the channel suction aperture is executed. <P>SOLUTION: When the operation button 16 is pushed to an intermediate position in a pushing operation range, the connection between a suction source duct 9 and a channel suction duct 7 is made while a situation is so maintained that the connection between the suction source duct 9 and a balloon suction duct 8 is blocked by an outer cylinder of a piston 14, and when the operation button 16 is pushed further, the connection between the suction source duct 9 and the balloon suction duct 8 is made through a space B which is formed between an inner peripheral surface of a cylinder body 11 and an outer peripheral surface of the outer cylinder of the piston 14. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
