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US4957418A Expired / Lapsed US ⏱️ 0.0 years remaining

Injection pump for internal combustion engines

Assignee: Robert Bosch GmbH
•
Filing: 1989-03-29
•
Granted: 1990-09-18
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Expires: 2009-03-29
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Abstract

Abstract An injection pump for internal combustion engines having a pump piston and a pump piston bushing, to which a suction chamber is connected, the connection of the suction chamber to the work chamber of the pump is overtaken by the pump piston upon supply onset, and in which a diversion of the pump pressure at the end of supply is effected by re-opening the communication with the suction chamber. At least one separate diversion chamber, defined by a pressure maintenance valve and a throttle is connected to the work chamber via a connection that is likewise openable and closable upon the compression stroke; this connection to the work chamber is opened earlier, at the end of pump supply, than a further connection to the suction chamber.

Inventors

  • 👤 Anton Pischinger
  • 👤 Theodor Stipek

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 16:12
CPC Classifications
F; F02; F02M; F02M59/00; F02M59/44; F02M55/00; F02M55/001

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 166 words
An injection pump for internal combustion engines, having a pump piston (2) in a pump bushing (1) a suction chamber (7) connected to said pump piston bushing, a connection (6) which connects said suction chamber to a work chamber (3) of the pump, said connection (6) is interrupted by the pump piston upon supply onset, and in which a diversion of the pump pressure at the end of supply is effected by re-opening a communication with the suction chamber, in which at least one separate diversion chamber (5), defined by a pressure maintenance means located in a wall portion separating said diversion chamber (5) from said work chamber (3) is connected to the work chamber (3) via a connection bore (4), said connection bore (4) is likewise openable and closable by the pump piston (2), and a connection of said connector bore (4) with the work chamber (3) is opened earlier, at the end of pump supply, than the connection (6) to the suction chamber (7).
Claim 2
Dependent Claim 166 words
An injection pump for internal combustion engines, having a pump piston (2) in a pump bushing (1) a suction chamber (7) connected to said pump piston bushing, a connection (6) which connects said suction chamber to a work chamber (3) of the pump, said connection (6) is interrupted by the pump piston upon supply onset, and in which a diversion of the pump pressure at the end of supply is effected by re-opening a communication with the suction chamber, in which at least one separate diversion chamber (5), defined by a pressure maintenance means located in a wall portion separating said diversion chamber (5) from said work chamber (3) is connected to the work chamber (3) via a connection bore (4), said connection bore (4) is likewise openable and closable by the pump piston (2), and a connection of said connector bore (4) with the work chamber (3) is opened earlier, at the end of pump supply, than the connection (6) to the suction chamber (7).
Claim 3
Dependent Claim 49 words
An injection pump as defined by claim 1, in which said connection bore (4) to the diversion chamber (5) is located with its upper edge in the direction of the compression stroke at a higher level than the upper edge of the connection (6) to the suction chamber (7).
Claim 4
Dependent Claim 34 words
An injection pump as defined by claim 1, in which a wall portion (10, 15) having a throttle (11, 17) and a pressure maintenance valve (16) is affixed onto the separate diversion chamber (5).
Claim 5
Dependent Claim 34 words
An injection pump as defined by claim 2, in which a wall portion (10, 15) having a throttle (11, 17) and a pressure maintenance valve (16) is affixed onto the separate diversion chamber (5).
Claim 6
Dependent Claim 36 words
An injection pump as defined by claim 3, in which said wall portion (15) having the throttle (17) and the pressure maintenance valve (16) additionally has a suction valve (18) opening into the diversion chamber (5).
Claim 7
Dependent Claim 36 words
An injection pump as defined by claim 4, in which said wall portion (15) having the throttle (17) and the pressure maintenance valve (16) additionally has a suction valve (18) opening into the diversion chamber (5).
Claim 8
Dependent Claim 25 words
An injection pump as defined by claim 1, in which a wall portion (10,15) having a throttle is affixed onto the separate diversion chamber (5).
Claim 9
Dependent Claim 26 words
An injection pump as defined by claim 2, in which a wall portion (10, 15) having a throttle is affixed onto the separate diversion chamber (5).
Claim 10
Dependent Claim 35 words
An injection pump as defined by claim 7, in which said wall portion (15) has a throttle (17) and a pressure maintenance valve (16) and a section valve (18) opening into the diversion chamber (5).
Claim 11
Dependent Claim 35 words
An injection pump as defined by claim 8, in which said wall portion (15) has the throttle (17) and a pressure maintenance valve (16) and a section valve (18) opening into the diversion chamber (5).

References Cited (Backward Citations)

GB530945A Cited
US3368491A Cited
DE2537344A1 Cited
US4172699A Cited
EP0269610A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-09-17 1994-03-19 1994-09-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-09-17 1998-03-19 1998-09-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-09-17 2002-03-19 2002-09-18 $7700.00 Window Closed / Lapsed

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