Air and water supply valve structure in endoscope

• US 6,346,075 B1
• Filed: 01/27/2000
• Issued: 02/12/2002
• Est. Priority Date: 02/01/1999
• Status: Expired due to Term

• Current Assignee: Fujinon Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Optical Co. Ltd (Fujifilm Holdings Corporation)
• Inventors: Kondo, Mitsuo, Arai, Kaoru, Kuboya, Hiroshi
• Primary Examiner(s): Dvorak, Linda C. M.
• Assistant Examiner(s): RAM, JOCELYN D
• Application Number:
  US09/492,836
• Time in Patent Office: 747 Days
• Field of Search: 600/159, 251/186, 251/190, 137/538, 137/625.67, 137/625.68
• US Class Current: 600/159
• CPC Class Codes: A61B 1/00068 Valve switch arrangements
• CPC Class Codes: A61B 1/015 Control of fluid supply or evacuation

Abstract

A piston of an air and water supply valve in an endoscope comprises: a base cylinder; a water supply switching piston; and an air supply switching piston, which is inserted in the water supply switching piston. An air supply button functioning as a check valve is attached to the top end of the air supply switching piston, and air is supplied by slightly pressing the air supply button and water is supplied by deeply pressing the air supply button. If liquid flows back, the air supply button functions as the check valve to prevent the backflow from flowing into the base cylinder from the air supply switching piston.

Claims

1. An air and water supply valve structure provided at a manual operation part of an endoscope, comprising:

a base cylinder that is a hollow cylinder connecting;

to an air feed tube feeding air into the base cylinder, to a water feed tube feeding water into the base cylinder, to an air supply tube to supply the air from the base cylinder to an air and water supply opening formed at an end of an insertion part of the endoscope, and to a water supply tube to supply the water from the base cylinder to the air and water supply opening;

a first piston that is a hollow cylinder slidably inserted into the base cylinder, the first piston having a connection opening to connect the air feed tube and an inner space of the first piston, the first piston having a connection passage to connect the water feed tube and the water supply tube;

a second piston that is a hollow cylinder arranged inside the first piston, an inner space of the second piston being connected to the air supply tube;

a first operation member provided to the second piston, the first operation member being pressed by first and second steps, the first operation member connecting, when pressed by the first step, the inner space of the first piston and the inner space of the second piston, and the first operation member disconnecting, when not pressed, the inner space of the first piston and the inner space of the second piston; and

a second operation member provided to the first piston, wherein when the first operation member is pressed by the second step, the second operation member is pressed and positions the first piston such that the connection opening of the first piston is disconnected from the air feed tube and that the connection passage of the first piston connects the water feed tube and the water supply tube.

2. The air and water supply valve structure as defined in claim 1, wherein the first operation member comprises a button with a connection opening to connect the inner space of the first piston and the inner space of the second piston.

3. The air and water supply valve structure as defined in claim 1, wherein:

the first operation member comprises a bag-shaped elastic member around which a cut groove is formed;

when the bag-shaped elastic member is not pressed, the cut groove is closed to disconnect the inner space of the first piston and the inner space of the second piston; and

when the bag-shaped elastic member is pressed by the first step, the bag-shaped elastic member is deformed and the cut groove is opened to connect the inner space of the first piston and the inner space of the second piston.

4. The air and water supply valve structure as defined in claim 1, wherein:

the first operation member comprises a spiral spring having adjacent spirals;

when the spiral spring is not pressed, the adjacent spirals are in close contact with one another to disconnect the inner space of the first piston and the inner space of the second piston; and

when the spiral spring is pressed by the first step, the spiral spring is buckled and gaps are formed between the adjacent spirals to connect the inner space of the first piston and the inner space of the second piston.

5. The air and water supply valve structure as defined in claim 1, wherein the first operation member comprises:

a shutter plate provided at an opening to connect the inner space of the first piston and the inner space of the second piston, the shutter plate opening and closing the opening when operated;

a forcing member that forces the shutter plate in such a direction as to close the opening; and

a pressing member that presses the shutter plate against the force of the forcing member in such a direction as to open the opening.

6. The air and water supply valve structure as defined in claim 1, wherein the air supply tube and the water supply tube are straight over predetermined lengths, respectively.

7. The air and water supply valve structure as defined in claim 1, wherein the air supply tube is straight and arranged parallel to an axial direction of the base cylinder over a predetermined length, the air supply tube having a mouth thereof within an inner diameter of the base cylinder.

8. A valve structure in an endoscope, comprising:

a first member having a first passage for a fluid, the first passage having a first opening; and

a second member having a second passage for the fluid, the second passage having a second opening;

wherein the first and second members are slidable with respect to one another in a sliding direction, the first and second passages are connected through the first and second openings when the first and second openings are faced to one another, the first and second passages are disconnected when the first and second openings are not faced to one another, and at least one of the first and second openings has a length thereof in the sliding direction being shorter than a length thereof in a direction perpendicular to the sliding direction.