← Back to Patent Explorer
US5664545A Expired / Lapsed US ⏱️ 0.0 years remaining

Fuel injection apparatus

Assignee: Denso Corp
•
Filing: 1995-11-30
•
Granted: 1997-09-09
•
Expires: 2015-11-30
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract According to the present invention, a fuel injection apparatus includes a casing having a control pressure chamber for storing fuel supplied from fuel passage, a needle valve to which fuel stored in the control pressure chamber applies pressure in the valve closing direction, a valve device for interrupting communication between the fuel passage and the control pressure chamber to seal fuel in said control pressure chamber, and volume changing device for expanding volume of the control pressure chamber after fuel is sealed in the control pressure chamber by the valve device. According to the above fuel injection device, pressure in the control pressure chamber is reduced while the fuel is stored therein by the volume changing device, the nozzle needle is lifted, and injection is started. For this reason, it is not necessary to supply surplus fuel in addition to the injection fuel during the fuel injection. In this way, the fuel supply pump is made smaller in size, and efficiency for use of supplied fuel can be improved. Further, since high-pressure fuel is not discharged from the fuel injection apparatus, pulsation within the common rail can be suppressed, and fuel injection can be stabilized.

Inventors

  • 👤 Masaaki Kato
  • 👤 Masahiro Okajima

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 21:18
CPC Classifications
F; F02; F02M; F02M47/00; F02M47/02; F02M47/027; F02M63/00; F02M63/0012; F02M63/0014; F02M63/0015; F02M63/0017; F02M63/0031; F02M63/0033; F02M63/0035; F02M63/0043; F02M2200/00; F02M2200/04

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 195 words
A fuel injection apparatus comprising: a casing having a sliding hole in an axial direction thereof, a fuel passage for introducing fuel into said casing, an injection opening provided at one end of said sliding hole to inject fuel supplied from said fuel passage, and a control pressure chamber provided at the other end of said sliding hole and for storing fuel supplied from said fuel passage; a needle valve slidably disposed in said sliding hole, said needle valve having a valve body at one end, said valve body opening said injection opening by fuel supplied to said injection opening through said fuel passage, and a piston at the other end, fuel stored in said control pressure chamber applying pressure to said piston to urge said needle valve in the valve closing direction; first urging means for urging said needle valve in the valve closing direction; a valve device for interrupting communication between said fuel passage and said control pressure chamber to seal fuel in said control pressure chamber; and a volume changing device for expanding volume of said control pressure chamber after fuel is sealed in said control pressure chamber by said valve device.
Claim 2
Dependent Claim 195 words
A fuel injection apparatus comprising: a casing having a sliding hole in an axial direction thereof, a fuel passage for introducing fuel into said casing, an injection opening provided at one end of said sliding hole to inject fuel supplied from said fuel passage, and a control pressure chamber provided at the other end of said sliding hole and for storing fuel supplied from said fuel passage; a needle valve slidably disposed in said sliding hole, said needle valve having a valve body at one end, said valve body opening said injection opening by fuel supplied to said injection opening through said fuel passage, and a piston at the other end, fuel stored in said control pressure chamber applying pressure to said piston to urge said needle valve in the valve closing direction; first urging means for urging said needle valve in the valve closing direction; a valve device for interrupting communication between said fuel passage and said control pressure chamber to seal fuel in said control pressure chamber; and a volume changing device for expanding volume of said control pressure chamber after fuel is sealed in said control pressure chamber by said valve device.
Claim 3
Dependent Claim 76 words
A fuel injection apparatus according to claim 1, wherein said valve device includes: a valve casing having a valve sliding hole therein; a valve member having a land portion which slides into said valve sliding hole to interrupt communication between said fuel passage and said control pressure chamber; second urging means for urging said valve member in one direction; and actuating means for actuating said valve member in the other direction resisting said second urging means.
Claim 4
Dependent Claim 42 words
A fuel injection apparatus according to claim 2, wherein said volume changing means for expanding volume of said control pressure chamber is configured by said land portion sliding in said valve sliding hole in a manner to expand said control pressure chamber.
Claim 5
Dependent Claim 43 words
A fuel injection apparatus according to claim 3, wherein said valve member further includes a fluid resistance portion which throttles a passage area between said second fuel passage and said control pressure chamber before said land .portion slides into said valve sliding hole.
Claim 6
Dependent Claim 15 words
A fuel-injection apparatus according to claim 2, wherein said valve member is a poppet valve.
Claim 7
Dependent Claim 15 words
A fuel-injection apparatus according to claim 2, wherein said valve member is a spool valve.
Claim 8
Dependent Claim 18 words
A fuel-injection apparatus according to claim 2, wherein said valve device is a two-position and two-port solenoid valve.
Claim 9
Dependent Claim 28 words
A fuel-injection apparatus according to claim 1, wherein said needle valve has a sliding portion which slides in said sliding hole, said sliding portion functions as said piston.
Claim 10
Dependent Claim 133 words
A fuel-injection apparatus according to claim 2, wherein said valve member further includes: a guide portion provided at one side of said land portion for guiding said valve member slidably within said valve casing; a first connecting portion for connecting said guide portion with said land portion and having a diameter smaller than said land portion; and a seat portion provided at the other side of said land portion and spreading out in said control pressure chamber, said seat portion seating on an opening of said valve sliding hole to said control pressure chamber; and second connecting portion for connecting said seat portion with said land portion; wherein said fuel passage is open to said valve sliding hole which is enclosed by said first connecting portion, said land portion and said guide portion.
Claim 11
Dependent Claim 179 words
A fuel injection apparatus comprising: a casing having a sliding hole in an axial direction thereof, a fuel passage for introducing fuel into said casing, an injection opening provided at one end of said sliding hole to inject fuel supplied from said fuel passage, and a control pressure chamber provided at the other end of said sliding hole and for storing fuel supplied from said fuel passage; a needle valve slidably disposed in said sliding hole, said needle valve having a valve body at one end, said valve body opening said injection opening by fuel supplied to said injection opening through said fuel passage, and a piston at the other end, fuel stored in said control pressure chamber applying pressure to said piston to urge said needle valve in the valve closing direction; first urging means for urging said needle valve in the valve closing direction; and a passage area varying single valve member for varying a passage area between said fuel passage and said control pressure chamber and for selectively closing said passage area to terminate flow therethrough.
Claim 12
Dependent Claim 179 words
A fuel injection apparatus comprising: a casing having a sliding hole in an axial direction thereof, a fuel passage for introducing fuel into said casing, an injection opening provided at one end of said sliding hole to inject fuel supplied from said fuel passage, and a control pressure chamber provided at the other end of said sliding hole and for storing fuel supplied from said fuel passage; a needle valve slidably disposed in said sliding hole, said needle valve having a valve body at one end, said valve body opening said injection opening by fuel supplied to said injection opening through said fuel passage, and a piston at the other end, fuel stored in said control pressure chamber applying pressure to said piston to urge said needle valve in the valve closing direction; first urging means for urging said needle valve in the valve closing direction; and a passage area varying single valve member for varying a passage area between said fuel passage and said control pressure chamber and for selectively closing said passage area to terminate flow therethrough.
Claim 13
Dependent Claim 29 words
A fuel injection apparatus according to claim 1, further comprising a passage area varying device for varying a passage area between said fuel passage and said control pressure chamber.

References Cited (Backward Citations)

US4603671A Cited
US4640252A Cited
US4946106A Cited
US4972997A Cited
US5156132A Cited
US5497950A Cited
US5438968A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-09-08 2001-03-10 2001-09-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-09-08 2005-03-10 2005-09-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-09-08 2009-03-10 2009-09-09 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag