초록 ▼

An ejector pump is provided which works to use dynamic energy of a jet of a main fluid emitted from a nozzle to suck a sub-fluid therein. When it is required to stop the ejector pump, the needle is moved to bring a sealing surface formed on a head thereof into abutment with a sealing surface formed

An ejector pump is provided which works to use dynamic energy of a jet of a main fluid emitted from a nozzle to suck a sub-fluid therein. When it is required to stop the ejector pump, the needle is moved to bring a sealing surface formed on a head thereof into abutment with a sealing surface formed around a main fluid flow path extending inside the ejector pump to close the main fluid flow path, thereby inhibiting the fluid pressure from acting on any downstream device. Upon the abutment, the needle is kept away from a nozzle, thereby avoiding undesirable wear or deformation of the needle and nozzle.

대표청구항 ▼

What is claimed is: 1. An ejector pump comprising: a flow path unit having formed therein a fluid discharge path leading to a fluid outlet; a nozzle body including a main fluid inlet port to which a main fluid is inputted, a nozzle which has a nozzle outlet from which a jet of the main fluid is emi

What is claimed is: 1. An ejector pump comprising: a flow path unit having formed therein a fluid discharge path leading to a fluid outlet; a nozzle body including a main fluid inlet port to which a main fluid is inputted, a nozzle which has a nozzle outlet from which a jet of the main fluid is emitted to the discharge path of said flow path unit and then discharged from the fluid outlet, and a main fluid flow path which has a length and communicates between the main fluid inlet port and the nozzle outlet of the nozzle, physical energy of the jet of the main fluid emitted from the nozzle serving to suck and direct a sub-fluid to the discharge path of said flow path unit, said nozzle body having a first sealing surface exposed to a portion of the main fluid flow path; a needle disposed coaxially within the main fluid flow path, said needle being slidable in a lengthwise direction of the main fluid flow path to change an open area of the nozzle outlet, said needle having a second sealing surface, when said needle is moved within the main fluid flow path and brings the second sealing surface thereof into abutment to the first sealing surface of said nozzle body, the main fluid flow path being closed; and a heater working to add thermal energy to the main fluid, said heater being disposed in a portion of said nozzle body which surrounds a location where the first sealing surface abuts the second sealing surface. 2. The ejector pump as set forth in claim 1, wherein said needle is kept away from the nozzle upon the abutment of the second sealing surface to the first sealing surface. 3. The ejector pump as set forth in claim 1, wherein said nozzle body has an inner wall forming the main fluid flow path, the inner wall having a shoulder defining the first sealing surface, and wherein said needle has a shoulder defining the second sealing surface. 4. An ejector pump comprising: a flow path unit having formed therein a fluid discharge path leading to a fluid outlet; a nozzle body including a main fluid inlet port to which a fluid is inputted, a nozzle which has a nozzle outlet from which a jet of the main fluid is emitted to the discharge path of said flow path unit and then discharged from the outlet, and a main fluid flow path which has a length and communicates between the main fluid inlet port and the nozzle outlet of the nozzle, physical energy of the jet of the main fluid emitted from the nozzle serving to suck and direct a sub-fluid to the discharge path of said flow path unit; a heater being disposed in said nozzle body and working to add thermal energy to the main fluid; and a heat transfer blocking interface formed between the nozzle body and the flow path unit. 5. The ejector pump as set forth in claim 4, wherein said heater is disposed in a portion of a circumference of said nozzle body in which the main fluid inlet port is formed. 6. The ejector pump as set forth in claim 4, wherein said heater is implemented by a constant temperature heater designed to perform a temperature self-control function. 7. The ejector pump as set forth in claim 4, wherein said nozzle body and said flow path unit are made of separate members, respectively. 8. The ejector pump as set forth in claim 4, further comprising a needle movable in a lengthwise direction of the main fluid flow path to change an open area of the nozzle outlet and a drive unit working to move the needle, and wherein said drive unit, said nozzle body, and the flow path unit are made of separate members, respectively. 9. A fuel cell system comprising: a fuel cell working to produce an electrical energy arising from chemical reaction of hydrogen with oxygen; a hydrogen supply line through which a hydrogen gas is supplied from a hydrogen supply device to said fuel cell; an off-gas circulation line working to circulate an off-gas, which is emitted from said fuel cell and contains an unreacted portion of the hydrogen gas not subjected to the chemical reaction, to said fuel cell through said hydrogen supply line; and an ejector pump installed in a junction of said hydrogen supply line and said off-gas circulation line, said ejector pump including (a) a flow path unit having formed therein a fluid discharge path leading to a fluid outlet, (b) a nozzle body including a main fluid inlet port to which the hydrogen gas supplied from the hydrogen supply device is inputted, a nozzle which has a nozzle outlet from which a jet of the hydrogen gas is emitted to the discharge path of said flow path unit and then discharged from the fluid outlet to said fuel cell through said hydrogen supply line, and a main fluid flow path which has a length and communicates between the main fluid inlet port and the nozzle outlet of the nozzle, physical energy of the jet of the hydrogen gas emitted from the nozzle serving to suck and mix the off-gas with the hydrogen gas emerging from the nozzle, said nozzle body having a first sealing surface exposed to a portion of the main fluid flow path, (c) a needle disposed coaxially within the main fluid flow path, said needle being slidable in a lengthwise direction of the main fluid flow path to change an open area of the nozzle outlet, said needle having a second sealing surface, when said needle is moved within the main flow path and brings the second sealing surface thereof into abutment to the first sealing surface of said nozzle body, the main fluid flow path being closed, and (d) a heater being disposed in said nozzle body and working to add thermal energy to the hydrogen gas; and a heat transfer blocking interface formed between the nozzle body and the flow path unit. 10. A fuel cell system comprising: a fuel cell working to produce an electrical energy arising from chemical reaction of hydrogen with oxygen; a hydrogen supply line through which a hydrogen gas is supplied from a hydrogen supply device to said fuel cell; an off-gas circulation line working to circulate an off-gas, which is emitted from said fuel cell and contains an unreacted portion of the hydrogen gas not subjected to the chemical reaction, to said fuel cell through said hydrogen supply line; and an ejector pump installed in a junction of said hydrogen supply line and said off-gas circulation line, said ejector pump including (a) a flow path unit having formed therein a fluid discharge path leading to a fluid outlet, (b) a nozzle body including a main fluid inlet port to which the hydrogen gas is inputted, a nozzle which has a nozzle outlet from which a jet of the hydrogen gas is emitted to the discharge path of said flow path unit and then discharged from the fluid outlet to said fuel cell through said hydrogen supply line, and a main fluid flow path which communicates between the main fluid inlet port and the nozzle outlet of the nozzle, physical energy of the jet of the hydrogen gas emitted from the nozzle serving to suck and mix the off-gas with the hydrogen gas emerging from the nozzle, and (c) a heater being disposed in said nozzle body and working to add thermal energy to the hydrogen gas; and a heat transfer blocking interface formed between the nozzle body and the flow path unit.