Pneumatic fender and mouth piece metal for pneumatic fender
View Patent ↗A pneumatic fender and a mouth piece metal with an open/close valve is biased by a resilient member toward a closing direction of a through hole formed on a dividing wall constituting a receiving chamber. A safety valve is isolated from a cavity of a fender bladder by a receiving chamber, thus allowing the safety valve to be able to be detached and attached while the pneumatic fender is in use. A confirmation test of a valve opening pressure of the safety valve is performed by opening a receiving chamber open/close valve and raising an internal pressure of a cavity of the receiving chamber to a pressure threshold (Pm) via a receiving chamber communication passage. Upon an internal pressure (P) of the cavity being less than the pressure threshold (Pm) and greater than a standard pressure (Pc), the open/close valve opens the through hole, thus allowing the safety valve to function.
1. A pneumatic fender comprising:
a fender bladder including a cylindrical portion and bowl-like hemispherical portions connected to each end of the cylindrical portion;
a mouth piece metal disposed on at least one of the hemispherical portions,
the mouth piece metal including:
a safety valve that, upon an internal pressure of a cavity of the fender bladder reaching a pressure threshold, opens to connect the cavity of the fender bladder to outside air and reduce the internal pressure, and
a communication passage that connects the cavity of the fender bladder and outside air; and
a bladder open/close valve that opens and closes the communication passage; wherein
the mouth piece metal further includes:
a receiving chamber that isolates the safety valve from the cavity of the fender bladder,
a through hole that connects a cavity of the receiving chamber and the cavity of the fender bladder, the through hole being formed on a dividing wall constituting the receiving chamber,
an open/close valve that opens and closes the through hole,
a resilient member that constantly biases the open/close valve toward a closing direction of the through hole,
a receiving chamber communication passage that connects the cavity of the receiving chamber and outside air, and
a receiving chamber open/close valve that opens and closes the receiving chamber communication passage; and
upon the internal pressure of the cavity of the fender bladder being less than the pressure threshold and greater than a standard pressure, which is a sum of a predetermined initial internal pressure and an allowable pressure, the open/close valve opens, opening the closed through hole.
2. The pneumatic fender according to claim 1 , wherein the allowable pressure is from 5 to 20%, both inclusive, of the predetermined initial internal pressure.
3. The pneumatic fender according to claim 2 , wherein the resilient member is a coil spring.
4. The pneumatic fender according to claim 3 , wherein the safety valve and the through hole are disposed coaxially to a cylinder axial direction of the fender bladder, and the open/close valve moves in the cylinder axial direction to open and close the through hole.
5. The pneumatic fender according to claim 1 , wherein the resilient member is a coil spring.
6. The pneumatic fender according to claim 1 , wherein the safety valve and the through hole are disposed coaxially to a cylinder axial direction of the fender bladder, and the open/close valve moves in the cylinder axial direction to open and close the through hole.
7. A mouth piece metal for a pneumatic fender comprising:
a safety valve that, upon an internal pressure of a cavity of a fender bladder reaching a pressure threshold, opens to connect the cavity of the fender bladder to outside air and reduce the internal pressure;
a communication passage that connects the cavity of the fender bladder and outside air; and
a bladder open/close valve that opens and closes the communication passage;
the mouth piece metal being attached to a bowl-like hemispherical portion constituting the fender bladder; wherein
the mouth piece metal further includes:
a receiving chamber that isolates the safety valve from the cavity of the fender bladder,
a through hole that connects a cavity of the receiving chamber and the cavity of the fender bladder, the through hole being formed on a dividing wall constituting the receiving chamber,
an open/close valve that opens and closes the through hole,
a resilient member that constantly biases the open/close valve toward a closing direction of the through hole,
a receiving chamber communication passage that connects the cavity of the receiving chamber and outside air, and
a receiving chamber open/close valve that opens and closes the receiving chamber communication passage; and
upon the internal pressure of the cavity of the fender bladder being less than the pressure threshold and greater than a standard pressure, which is a sum of a predetermined initial internal pressure and an allowable pressure, the open/close valve opens, opening the closed through hole.
8. The mouth piece metal for a pneumatic fender according to claim 7 , wherein the allowable pressure is from 5 to 20%, both inclusive, of the predetermined initial internal pressure.
9. The mouth piece metal for a pneumatic fender according to claim 8 , wherein the resilient member is a coil spring.
10. The mouth piece metal for a pneumatic fender according to claim 9 , wherein the safety valve and the through hole are disposed coaxially to a cylinder axial direction of the fender bladder, and the open/close valve moves in the cylinder axial direction to open and close the through hole.
11. The mouth piece metal for a pneumatic fender according to claim 7 , wherein the resilient member is a coil spring.
12. The mouth piece metal for a pneumatic fender according to claim 7 , wherein the safety valve and the through hole are disposed coaxially to a cylinder axial direction of the fender bladder, and the open/close valve moves in the cylinder axial direction to open and close the through hole.