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.

Abstract: One embodiment relates to a valve device. The valve device includes: a valve case; a valve element slidably disposed within a valve chamber defined in the valve case; and a positive pressure spring configured to urge the valve element toward a valve seat in the valve case. The valve element includes an outer circumferential portion having a predetermined length extending along an inner circumference of the valve chamber. The outer circumferential portion includes plural opening portions. And, ribs project from the inner circumference of the valve chamber to enter into the opening portions, thereby limiting movement of the positive pressure spring in a radial direction.

Abstract: An embodiment provides a check valve including a valve case, a positive pressure valve having a resin ring sealing member, and a resin negative pressure valve. The positive pressure valve and the negative pressure valve are disposed in the valve case. The positive pressure valve includes a first mount surface and a second mount surface disposed on an inner diameter side of the first mount surface. In the valve case, a presser cap is mounted on the positive pressure valve so as to sandwich the ring sealing member and the negative pressure valve with the first mount surface and the second mount surface of the positive pressure valve.

Abstract: One embodiment relates to a valve device. The valve device includes: a valve case; a valve element slidably disposed within a valve chamber defined in the valve case; and a positive pressure spring configured to urge the valve element toward a valve seat in the valve case. The valve element includes an outer circumferential portion having a predetermined length extending along an inner circumference of the valve chamber. The outer circumferential portion includes plural opening portions. And, ribs project from the inner circumference of the valve chamber to enter into the opening portions, thereby limiting movement of the positive pressure spring in a radial direction.

Abstract: One embodiment provides a check valve including 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.

Abstract: An embodiment provides a check valve including a valve case, a positive pressure valve having a resin ring sealing member, and a resin negative pressure valve. The positive pressure valve and the negative pressure valve are disposed in the valve case. The positive pressure valve includes a first mount surface and a second mount surface disposed on an inner diameter side of the first mount surface. In the valve case, a presser cap is mounted on the positive pressure valve so as to sandwich the ring sealing member and the negative pressure valve with the first mount surface and the second mount surface of the positive pressure valve.

Abstract: A check valve includes a casing including a positive pressure valve seat, a positive pressure valve urged by a positive pressure valve spring and including a negative pressure valve seat, and a negative pressure valve assembled to the positive pressure valve and urged by a negative pressure valve spring, where the positive pressure valve includes an inner cylinder, an outer cylinder that is connected with an outer circumference of the inner cylinder via ribs, and passages formed between the inner cylinder and the outer cylinder, where the positive pressure valve spring is disposed the casing and the outer cylinder, and where the negative pressure valve spring is disposed in the inner cylinder.

Abstract: A check valve includes a casing including a positive pressure valve seat, a positive pressure valve urged by a positive pressure valve spring and including a negative pressure valve seat, and a negative pressure valve assembled to the positive pressure valve and urged by a negative pressure valve spring, where the positive pressure valve includes an inner cylinder, an outer cylinder that is connected with an outer circumference of the inner cylinder via ribs, and passages formed between the inner cylinder and the outer cylinder, where the positive pressure valve spring is disposed the casing and the outer cylinder, and where the negative pressure valve spring is disposed in the inner cylinder.

Abstract: A check valve includes a main-casing, a sub-casing, a positive-pressure valve and a negative-pressure valve. The positive-pressure valve has through holes and a negative-pressure valve seat. The negative-pressure valve has leg portions. A cap is disposed within the positive-pressure valve. A positive-pressure spring is disposed between the positive-pressure valve and the sub-casing, and a negative-pressure spring is disposed between the positive-pressure valve and the cap. A positive-pressure flow path for releasing fuel vapor is formed between an outer circumference of the positive-pressure valve and an inner circumference of the main-casing, at further outward position than the positive-pressure spring. A negative-pressure flow path for introducing outside air is formed between an inner circumference of the positive-pressure valve and the leg portions and an outer circumference of the cap and between the through holes and the leg portions, at further outward position than the negative-pressure spring.

Abstract: According to an aspect of the present invention, there is provided a fuel tank check valve including: a main tubular body attached on a fuel filler pipe; a valve element; a first tube that is disposed between the main tubular body and the fuel filler pipe and that has a first locking portion to engage with the fuel filler pipe; an annular seal member; and a second tube that is disposed to sandwich the annular seal member with the first tube and that has a second locking portion to engage with the main tubular body, wherein the fuel filler pipe is disposed on an inner circumferential surface of the first tube, wherein the first locking portion projects in an inside diameter direction, and wherein the first locking portion engages with an engagement hole in the fuel filler pipe from an outside.

Abstract: There is provided a check valve which can reduce the operation noise of a positive-pressure valve and a negative-pressure valve when they slide and which can facilitate the assemblage work of the positive-pressure valve and the negative-pressure valve. The check valve 1 includes a main-casing 10, a sub-casing 20, a positive-pressure valve 30 and a negative-pressure valve 50. The positive-pressure valve 30 has through holes 39 and a negative-pressure valve seat 36a. The negative-pressure valve 50 has leg portions 53. A cap 60 is disposed within the positive-pressure valve 30. A positive-pressure spring S1 is disposed between the positive-pressure valve 30 and the sub-casing 20, and a negative-pressure spring S2 is disposed between the positive-pressure valve 30 and the cap 60.

Abstract: According to an aspect of the present invention, there is provided a fuel tank check valve including: a main tubular body attached on a fuel filler pipe; a valve element; a first tube that is disposed between the main tubular body and the fuel filler pipe and that has a first locking portion to engage with the fuel filler pipe; an annular seal member; and a second tube that is disposed to sandwich the annular seal member with the first tube and that has a second locking portion to engage with the main tubular body, wherein the fuel filler pipe is disposed on an inner circumferential surface of the first tube, wherein the first locking portion projects in an inside diameter direction, and wherein the first locking portion engages with an engagement hole in the fuel filler pipe from an outside.