At abnormal pressure pulsation generating time, a piston of a pulsation reducing apparatus is displaced in a valve chamber due to an increase in a fuel pressure in an upstream side fuel passage, so that fluid communication between a valve chamber and a downstream side fuel passage is disabled, and f
At abnormal pressure pulsation generating time, a piston of a pulsation reducing apparatus is displaced in a valve chamber due to an increase in a fuel pressure in an upstream side fuel passage, so that fluid communication between a valve chamber and a downstream side fuel passage is disabled, and fluid communication between a valve chamber side end part of a return passage and the valve chamber is enabled. Pressure pulsation is conducted into the return passage and is reduced by a damping effect of a pulsation reducing mechanism and a flow restricting effect of orifices. The fuel, which has passed through the orifices, is returned to the upstream side fuel passage through the return passage.
대표청구항▼
1. A pulsation reducing apparatus for a fuel supply system of an internal combustion engine that includes a fuel pump, which pumps fuel out of a fuel tank, and a fuel filter, which receives the fuel from the fuel tank through a fuel passage upon pumping of the fuel by the fuel pump and filters the f
1. A pulsation reducing apparatus for a fuel supply system of an internal combustion engine that includes a fuel pump, which pumps fuel out of a fuel tank, and a fuel filter, which receives the fuel from the fuel tank through a fuel passage upon pumping of the fuel by the fuel pump and filters the fuel, the pulsation reducing apparatus being adapted to reduce pressure pulsation of the fuel, which is generated in the fuel passage and is conducted to the fuel filter in the fuel passage due to operation of the fuel pump, and comprising: a passage cross-sectional area reducing device that reduces a passage cross-sectional area of a predetermined location of the fuel passage on an upstream side of the fuel filter in a flow direction of the fuel when a pressure of the fuel in the fuel passage becomes equal to or higher than a predetermined pressure, wherein the passage cross-sectional area reducing device is placed in the fuel passage on the upstream side of the fuel filter;a pulsation reducing device that reduces a pressure pulsation of the fuel on an upstream side of the predetermined location of the fuel passage in the flow direction of the fuel; anda connection passage that is connected to the fuel passage at one connection of the connection passage, which is located on the upstream side of the predetermined location of the fuel passage, wherein: the pulsation reducing device is placed in the connection passage;fluid communication between the fuel passage and the connection passage is enabled by reducing the passage cross-sectional area of the fuel passage with the passage cross-sectional area reducing device;the connection passage is further connected to the fuel passage at another connection of the connection passage, which is located on an upstream side of the one connection of the connection passage connected to the fuel passage; andthe connection passage is adapted to output the fuel, which is supplied into the connection passage from the one connection of the connection passage, toward an upstream side of the connection passage. 2. The pulsation reducing apparatus according to claim 1, wherein the pulsation reducing device includes: a valve member that is slidably placed in the connection passage; anda resilient member that is adapted to exert a resilient force against the valve member to displace the valve member. 3. The pulsation reducing apparatus according to claim 1, wherein: the fuel pump includes: a low pressure pump that pumps the fuel out of the fuel tank; anda high pressure pump that pressurizes and discharges the fuel, which is supplied from the low pressure pump through the fuel passage and the fuel filter. 4. The pulsation reducing apparatus according to claim 3, wherein: the fuel pump further includes a pressure regulator valve; andthe pressure regulator valve regulates the pressure of the fuel, which is drawn from the fuel tank by the low pressure pump, at a predetermined pressure or less and supplies the regulated fuel to the fuel filter in the fuel passage. 5. The pulsation reducing apparatus according to claim 1, wherein the fuel filter is placed in the fuel passage at a location between an inlet of the fuel pump, into which the fuel drawn from the fuel tank is supplied, and the fuel tank. 6. The pulsation reducing apparatus according to claim 1, wherein the passage cross-sectional area reducing device closes the fuel passage when the pressure of the fuel in the fuel passage becomes equal to or larger than the predetermined pressure. 7. A pulsation reducing apparatus for fuel supply system of an internal combustion engine that includes a fuel pump, which pumps out of a fuel tank, and a fuel filter, which receives the fuel from the fuel tank through a fuel passage upon pumping of the fuel by the fuel pump and filters the fuel, the pulsation reducing apparatus being adapted to reduce pressure pulsation of the fuel, which is generated in the fuel passage and is conducted to the fuel filter in the fuel passage due to operation of the fuel pump, and comprising: a passage cross-sectional area reducing device that reduces a passage cross-sectional area of a predetermined location of the fuel passage on an upstream side of the fuel filter in a flow direction of the fuel when a pressure of the fuel in the fuel passage becomes equal to or higher than a predetermined pressure, wherein the passage cross-sectional area reducing device is placed in the fuel passage on the upstream side of the fuel filter;a pulsation reducing device that reduces a pressure pulsation of the fuel on an upstream side of the predetermined location of the fuel passage in the flow direction of the fuel; anda connection passage that is connected to the fuel passage at one connection of the connection passage, which is located on the upstream side of the predetermined location of the fuel passage, wherein: the pulsation reducing device is placed in the connection passage;fluid communication between the fuel passage and the connection passage is enabled by reducing the passage cross-sectional area of the fuel passage with the passage cross-sectional area reducing device;the connection passage is further connected to the fuel passage at another connection of the connection passage, which is located on an upstream side of the one connection of the connection passage;the pulsation reducing apparatus further comprises an upstream side valve member, which is placed in the connection passage and is adapted to be opened by a predetermined valve opening pressure to conduct the fuel from the fuel passage into the connection passage through the another connection of the connection passage;the pulsation reducing device is placed on an upstream side of the upstream side valve member in the flow direction of the fuel along the connection passage and includes: a valve member that is slidably placed in the connection passage; anda resilient member that is adapted to exert a resilient force against the valve member to displace the valve member; andthe predetermined valve opening pressure of the upstream side valve member is set to be higher than the pressure of the fuel, which causes the reduction of the passage cross-sectional area of the fuel passage by the passage cross-sectional area reducing device. 8. The pulsation reducing apparatus according to claim 7, further comprising a downstream side valve member that reduces a passage cross-sectional area of the connection passage at a location where the one connection is located when a pressure of the fuel in the connection passage becomes equal to or higher than a predetermined pressure. 9. A pulsation reducing apparatus for a fuel supply system of an internal combustion engine that includes a fuel pump, which pumps fuel out of a fuel tank, and a fuel filter, which receives the fuel from the fuel tank through a fuel passage upon pumping of the fuel by the fuel pump and filters the fuel, the pulsation reducing apparatus being adapted to reduce pressure pulsation of the fuel, which is generated in the fuel passage and is conducted to the fuel filter in the fuel passage due to operation of the fuel pump, and comprising: a passage cross-sectional area reducing device that reduces a passage cross-sectional area of a predetermined location of the fuel passage on an upstream side of the fuel filter in a flow direction of the fuel when a pressure of the fuel in the fuel passage becomes equal to or higher than a predetermined pressure, wherein the passage cross-sectional area reducing device is placed in the fuel passage on the upstream side of the fuel filter;a pulsation reducing device that reduces a pressure pulsation of the fuel on an upstream side of the predetermined location of the fuel passage in the flow direction of the fuel; anda connection passage that is connected to the fuel passage at one connection of the connection passage, which is located on the upstream side of the predetermined location of the fuel passage, wherein: the pulsation reducing device is placed in the connection passage, the pulsation reducing device including: a valve member that is slidably placed in the connection passage; anda resilient member that is adapted to exert a resilient force against the valve member to displace the valve member;fluid communication between the fuel passage and the connection passage is enabled by reducing the passage cross-sectional area of the fuel passage with the passage cross-sectional area reducing device; andat least one valve hole is formed through the valve member to communicate the connection passage therethrough. 10. A pulsation reducing apparatus for a fuel supply system of an internal combustion engine that includes a fuel pump, which pumps fuel out of a fuel tank, and a fuel filter, which receives the fuel from the fuel tank through a fuel passage upon pumping of the fuel by the fuel pump and filters the fuel, the pulsation reducing apparatus being adapted to reduce pressure pulsation of the fuel, which is generated in the fuel passage and is conducted to the fuel filter in the fuel passage due to operation of the fuel pump, and comprising: a passage cross-sectional area reducing device that reduces a passage cross-sectional area of a predetermined location of the fuel passage on an upstream side of the fuel filter in a flow direction of the fuel when a pressure of the fuel in the fuel passage becomes equal to or higher than a predetermined pressure, wherein:the passage cross-sectional area reducing device is placed in the fuel passage on the upstream side of the fuel filterthe passage cross-sectional area reducing device includes a piston that is slidably received in the fuel passage;the piston has a passage, which extends through the piston in an inside of the piston to conduct the fuel; andan opening area of an outlet of the passage of the piston, which is communicated with the fuel filter, is reduced when the pressure of the fuel in the fuel passage becomes equal to or higher than the predetermined pressure.
연구과제 타임라인
LOADING...
LOADING...
LOADING...
LOADING...
LOADING...
이 특허에 인용된 특허 (24)
Inoue, Toshio; Harada, Osamu; Fushiki, Shunsuke; Ando, Daigo, Control device for internal combustion engine.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.