Check valve
AssigneePiolax, Inc.
InventorKosei Yamaguchi
Life of this patent
Estimating the term…
Abstract
A check valve includes a valve case, a positive pressure valve, a spring, and a negative pressure valve. The positive pressure valve is slidably disposed in a valve chamber of the valve case. The spring urges the positive pressure valve to abut on a positive pressure valve seat of the valve case. The negative pressure valve is on the positive pressure valve to abut on a negative pressure valve seat of the positive pressure valve. The negative pressure valve closes a communicating passage in the positive pressure valve in a normal state, and opens it when a pressure in the fuel tank falls to a predetermined value or less.
Claims11
A check valve mounted on a fuel tank of an automobile, the check valve comprising:
- a valve case comprising:
- a first connecting portion connected with a pipe which is to be communicated with the fuel tank;
- a second connecting portion connected with a pipe which is to be communicated with a canister disposed outside the fuel tank;
- a valve chamber formed inside the valve case;
- and
- a positive pressure valve seat provided in a portion ranging from the valve chamber to the first connecting portion;
- a positive pressure valve slidably disposed in the valve chamber to abut on and separate from the positive pressure valve seat;
- and
- a spring disposed in the valve case configured to urge to make the positive pressure valve abut on the positive pressure valve seat, and to be compressed to thereby open the positive pressure valve when a pressure in the fuel tank rises to a predetermined value or more,
- wherein the positive pressure valve comprises:
- a valve main body;
- an annular sealing member made from an elastic resin material, and mounted on the valve main body so as to abut on and separate from the positive pressure valve seat;
- and
- a retainer mounted on the valve main body so as to sandwich the annular sealing member with the valve main body,
- wherein the valve main body comprises:
- a placing face on which the annular sealing member is placed,
- wherein the retainer comprises:
- a communicating passage disposed on an inside diameter side of the annular sealing member;
- a sandwiching portion formed to sandwich the annular sealing member with the placing face of the valve main body;
- and
- a negative pressure valve seat which communicates with the communicating passage,
- wherein the check valve further comprises a negative pressure valve made from an elastic resin material, and mounted on the retainer so as to abut on and separate from the negative pressure valve seat, such that the negative pressure valve closes the communicating passage in a normal state by abutting on the negative pressure valve seat, and opens the communicating passage when the pressure in the fuel tank falls to a predetermined value or less,
- wherein the retainer includes a cylindrical portion,
- wherein the sandwiching portion includes a portion having a flange shape which extends radially outward from an outer circumference of the cylindrical portion, and
- wherein the negative pressure valve seat is formed in the portion of the sandwiching portion having the flange shape.
Dependencies are inferred from the claim text.