Suction device for endoscope

Claim 1

A suction device for an endoscope, the endoscope having a forceps receiver which has a closable forceps insertion bore therein, comprising: means for forming a suction path extending from said forceps insetion bore; and a plug assembly detachably inserted in said suction path in close contact with said suction path forming means, said plug assembly comprising: a ring, a piston, at least one portion of which is made of a deformable material; and a cylinder member into which said piston is slidably fitted, said cylinder member having valve seats formed at first and second portions thereof, said piston having first and second abutting portions for alternatively engaging said first and second valve seats, wherein abutment with the first valve seat allows passage of ambient air into said bore and wherein abutment with the second valve seat allows for suction in said bore said piston further having an elastic extended member extending outwardly away from said forceps insertion bore from said portion made of said elastic material, said extended member having an end portion abutting against said ring, said extended member biasing said piston so that said piston tends to move outwardly away from said forceps insertion bore, said cylinder member being provided with a suction hole; and a suction pump coupled to said suction hole.