Patents by Inventor Gerald Hofer

Gerald Hofer has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4649883
    Abstract: A fuel injection pump which has a shutoff device for the fuel supply to the pump work chamber, comprising a magnetic valve, which controls an intake bore to the work chamber of the fuel injection pump. The fuel injection pump further has a relief conduit, which is connected by an annular slide on the pump piston with the suction chamber in order to terminate the effective supply stroke of the pump piston. In order to assure reliable shutoff of the fuel supply to the pump work chamber, a check valve is further disposed in the connection between the pump work chamber and the suction chamber, which check valve is closed, during the intake stroke of the pump piston, with the collaboration of the pressure drop from the suction chamber to the pump work chamber.
    Type: Grant
    Filed: May 16, 1984
    Date of Patent: March 17, 1987
    Assignee: Robert Bosch GmbH
    Inventors: Wilfried Bohringer, Franz Eheim, Gerald Hofer, Karl Konrath, Helmut Laufer
  • Patent number: 4649879
    Abstract: An rpm governor for fuel injection pumps of internal combustion engines having two governor levers, namely a first lever engaged by a governor spring and a second lever which actuates the injection quantity control member and is engaged in the opposite direction from the governor spring by an rpm signal transducer, and having an intermediate spring between the two levers, is proposed, in which the intermediate spring is embodied as a spring package of relatively stiffer and softer springs in line with one another, of which the stiffer spring is effective for brief variations in force while the softer spring is contrarily effective for longer-lasting force effects. Structurally, this is attained by means of a hydraulic or pneumatic damping member (dashpot) which receives the softer spring.
    Type: Grant
    Filed: May 20, 1985
    Date of Patent: March 17, 1987
    Assignee: Robert Bosch GmbH
    Inventors: Gerald Hofer, Manfred Schwarz
  • Patent number: 4630587
    Abstract: The injection pump includes a pump cylinder, a pump piston moving into it and a hydraulic device for adjusting the instant of injection. The adjusting device has an adjusting cylinder, which is directed parallel to the pump cylinder and is accommodated in the housing of the injection pump, and adjusting piston and a restoring spring and adjusts a control sleeve, which opens the pump piston provided with at least one control recess in the longitudinal direction of the pump piston. This orientation and disposition of the adjusting cylinder effects a space-saving and inexpensive design of the injection pump and improves the precision of adjustment. The adjusting piston and the control sleeve may be directed coaxially and embodied as a single component, as a result of which a further space saving and increase in adjustment precision are attained.
    Type: Grant
    Filed: October 4, 1982
    Date of Patent: December 23, 1986
    Assignee: Robert Bosch GmbH
    Inventors: Gerald Hofer, Eberhard Hofmann, Helmut Laufer, Francois Rossignol, Reinhard Schwartz, Max Straubel, Raymond Tissot
  • Patent number: 4628957
    Abstract: Disclosed is a pressure valve connectable between a fuel injection pump and the fuel injection valve of an internal combustion engine. The valve includes a cylindrical valve closing member which moves due to the pressure of fuel from the pump and expells a quantity of fuel to the injection valve. A throttling passage is provided as a bypass to the closing member and guarantees a stable pressure in the fuel supply conduit when the closing member is in open position. To neutralize reflected pressure waves in the supply conduit after injection the valve closing body is delayed by the throttling passage during its return movement into closing position. In addition, a check valve is arranged in the closing member which controls the stable pressure to a desired value.
    Type: Grant
    Filed: November 27, 1984
    Date of Patent: December 16, 1986
    Assignee: Robert Bosch GmbH
    Inventors: Gerald Hofer, Helmut Laufer
  • Patent number: 4590913
    Abstract: A fuel injection pump having a hydraulic injection onset adjuster, an rpm governor with at least one member operating in accordance with load, and a full-load stop of the governor which limits the maximum injection quantity is proposed, in which between the full-load stop and the governor member adjustable in accordance with load a switch is provided, which switch upon a change from full load to partial load triggers a magnetic valve, to thereby effect a shift of the injection onset toward "late". The magnetic valve, to this end, engages the hydraulic control of the injection adjuster.
    Type: Grant
    Filed: June 3, 1985
    Date of Patent: May 27, 1986
    Assignee: Robert Bosch GmbH
    Inventors: Werner Faupel, Gerald Hofer
  • Patent number: 4541385
    Abstract: A fuel injection system (FIG. 1) provided with pump/nozzles is proposed, which has a central fuel metering device which functions with a deviation or metering piston and a distributor or multi-way valve as a metering control member.
    Type: Grant
    Filed: October 20, 1983
    Date of Patent: September 17, 1985
    Assignee: Robert Bosch GmbH
    Inventors: Franz Eheim, Gerald Hofer, Konrad Eckert, Heinz Links
  • Patent number: 4519352
    Abstract: A fuel injection pump including a control device is proposed in which a control lever which determines the fuel injection quantity is placed at an adjustable spring which is not supported by the main power source of a governor lever. The control lever is subjected to lesser forces provided by the intended auxiliary springs, starting springs or idling springs.
    Type: Grant
    Filed: September 28, 1982
    Date of Patent: May 28, 1985
    Assignee: Robert Bosch GmbH
    Inventors: Franz Eheim, Gerald Hofer, Karl Konrath, Max Straubel
  • Patent number: 4512308
    Abstract: A fuel injection pump in which the quantity adjustment member has a travel limitation in the form of an adjustable stop, which is adjusted in accordance with the displacement of an adjusting piston in accordance with a contour defined on the adjusting piston. The displacement of the adjusting piston is effected with the rpm-dependent pressure of the suction chamber of the fuel injection pump, and the work chamber preceding the adjusting piston can be uncoupled from the suction chamber via a throttle. The maximum displacement of the adjusting piston is limited by a stop which is adjustable in accordance with charge pressure or by a pressure control device by means of which the pressure in the work chamber can be adjusted or limited.
    Type: Grant
    Filed: September 28, 1982
    Date of Patent: April 23, 1985
    Assignee: Robert Bosch GmbH
    Inventors: Gerald Hofer, Max Straubel, Franz Eheim
  • Patent number: 4501252
    Abstract: A fuel injection pump in which the beginning of fuel injection can be adjusted to begin earlier than normal, particularly during warm-up by means of an adjusting piston. The adjustment takes place by changing the tension of the return spring which cooperates with the fuel injection adjustment piston.
    Type: Grant
    Filed: September 19, 1977
    Date of Patent: February 26, 1985
    Assignee: Robert Bosch GmbH
    Inventors: Gerhard Stumpp, Hans-Jorg Vogtmann, Paul Fussner, Manfred Schwarz, Gerald Hofer, Karl Konrath, Max Straubel, Werner Faupel
  • Patent number: 4496192
    Abstract: A pressure medium brake system for motor vehicles is proposed in which a high-pressure-producing apparatus and a normal-pressure brake apparatus are provided. The brake pressure is reduced with the aid of pressure limiters from high pressure to normal pressure. In order to attain rapid filling of the brake cylinders, one relay valve is disposed before each group of brake cylinders, the relay valves being triggered with normal pressure and very rapidly directing the high pressure into the brake cylinders with a large pressure drop. Upon attaining the maximum pressure level of the normal pressure, the supply of high pressure in the relay valve is cut off. The pressure medium brake system is preferably used as a compressed-air brake system for trucks and trailer-trucks.
    Type: Grant
    Filed: July 7, 1982
    Date of Patent: January 29, 1985
    Assignee: Robert Bosch GmbH
    Inventors: Ingolf Grauel, Gerald Hofer, Gunter Kulke, Werner Stumpe
  • Patent number: 4489698
    Abstract: A fuel injection pump for Diesel engines in which a rotating and reciprocating piston pressurizes and distributes fuel to individual pressure lines leading to the injection valves of the engine. In order to change the timing of injection with respect to the engine cycle, there is provided a mechanism to change the relative angle between the pressurizing piston and its drive means, which runs in synchronism with the engine. The mechanism operates hydraulically and is affected by the fuel pressure in the sump of the injection pump. There is also provided a hydraulic control valve mechanism which permits varying amounts of fuel to flow back from the sump to the low pressure side of the fuel delivery pump, thereby changing the injection timing. A primary control valve adjusts the sump pressure on the basis of engine speed while a secondary control valve adjusts the sump pressure on the basis of engine temperature in order to adapt the timing of fuel injection to engine starting and engine warm-up.
    Type: Grant
    Filed: March 24, 1983
    Date of Patent: December 25, 1984
    Assignee: Robert Bosch GmbH
    Inventors: Gerald Hofer, Karl Konrath, Franz Eheim, Otmar Weiss, Edgar Schmitt, Werner Faupel, Edgar Gotz
  • Patent number: 4483297
    Abstract: A fuel injection pump is proposed, which has a centrifugal governor disposed in the suction chamber of the fuel injection pump, the governor having a sleeve displaceable on a piston, and a pressure chamber enclosed in the interior of the governor sleeve, the latter being defined by the end face of the piston. By means of a relief line of the pressure chamber which is opened in the offset position of the governor sleeve, the restoring force on the centrifugal governor is increased during starting by the amount of the pressure difference appearing at the governor sleeve. Beyond a predetermined adjustment of the governor sleeve, the relief line is blocked, so that the governor can function unhindered within the normal operational range. The hysteresis thus resulting upon the shut-off of the increased starting quantity improves the behavior of the engine as it runs up to operational speed.
    Type: Grant
    Filed: August 23, 1982
    Date of Patent: November 20, 1984
    Assignee: Robert Bosch
    Inventors: Franz Eheim, Gerald Hofer, Claus Koster, Karl Konrath, Manfred Schwarz
  • Patent number: 4461255
    Abstract: An rpm governor is proposed, in which intervention into the regulation process can be made directly via a magnet, so that the degree of proportionality, particularly with isostatic governors, can be lowered to a minimum.
    Type: Grant
    Filed: November 2, 1982
    Date of Patent: July 24, 1984
    Assignee: Robert Bosch GmbH
    Inventors: Franz Eheim, Gerald Hofer
  • Patent number: 4450805
    Abstract: A fuel injection pump is proposed in which the quantity adjustment member has a travel limitation device in the form of an adjustable stop, which is adjusted in accordance with the displacement of an adjusting piston in accordance with a contour formed in the jacket face thereon. The displacement of the adjusting piston is effected via rpm-dependent pressure of the suction chamber counter to the force of a restoring spring and counter to a pressure which can be established with the aid of a pressure control valve in accordance with engine operating parameters. The adjustment of the stop is thus effected with the high work capacity of the suction chamber pressure, and the limitation of the adjustment is attained with the aid of the modulated pressure diverted from the suction chamber pressure.
    Type: Grant
    Filed: September 8, 1982
    Date of Patent: May 29, 1984
    Assignee: Robert Bosch GmbH
    Inventors: Franz Eheim, Gerald Hofer
  • Patent number: 4444170
    Abstract: A fuel injection pump, the volume adjustment member of which has a limiter of its play in the form of an adjustable device, which is movable in accordance with the displacement of a control piston in response to a contour provided in the control piston. The displacement of the first control piston occurs in accordance with the pressure of the air supplied to the combustion chambers of the internal combustion engine, and this in turn is controlled with the aid of a pressure element. The pressure element actuates a control piston, with the aid of which a control pressure is created which actuates the first control piston. The control pressure, at the same time, acts on the pressure element by way of the second control piston in the form of return pressure. In a state of equilibrium the control pressure circuit is separated from the pressure source.
    Type: Grant
    Filed: August 19, 1982
    Date of Patent: April 24, 1984
    Assignee: Robert Bosch GmbH
    Inventor: Gerald Hofer
  • Patent number: 4409939
    Abstract: A fuel injection system is proposed which has a high-pressure pump, a fuel reservoir determining the injection pressure, and an intermediate piston, during whose first half-stroke meters fuel under low pressure and during a second half-stroke, driven by the reservoir, injects the metered fuel. In order to vary the duration of injection, the pressure in the reservoir is determined either by means of the supply quantity of the high-pressure pump or by means of an appropriate pressure control valve in an outflow conduit.
    Type: Grant
    Filed: February 6, 1981
    Date of Patent: October 18, 1983
    Assignee: Robert Bosch GmbH
    Inventors: Franz Eheim, Gerald Hofer, Helmut Laufer
  • Patent number: 4407250
    Abstract: The invention relates to a fuel injection system having a pump/nozzle for which the fuel is metered by one apparatus and the injection onset is determined by a second apparatus. In accordance with the invention, these apparatuses each operate with a distributor, both distributors being combined into a single structural unit. Because of this combination, structural possibilities are created which, both functionally and in terms of manufacturing cost, represent substantial improvements in the field of injection systems.
    Type: Grant
    Filed: January 15, 1981
    Date of Patent: October 4, 1983
    Assignee: Robert Bosch GmbH
    Inventors: Franz Eheim, Gerald Hofer, Heins Links
  • Patent number: 4402290
    Abstract: A fuel injection pump is proposed which can be shut off by a magnetic valve if there is a danger of engine "cranking". The magnetic valve is triggered via a switch system in which one switch is actuatable with the adjusting lever of the injection pump, wherein the magnetic valve is furthermore controllable by the supply pump pressure.
    Type: Grant
    Filed: November 10, 1980
    Date of Patent: September 6, 1983
    Assignee: Robert Bosch GmbH
    Inventor: Gerald Hofer
  • Patent number: 4395990
    Abstract: A fuel injection pump for Diesel engines in which a rotating and reciprocating piston pressurizes and distributes fuel to individual pressure lines leading to the injection valves of the engine. In order to change the timing of injection with respect to the engine cycle, there is provided a mechanism to change the relative angle between the pressurizing piston and its drive means, which runs in synchronism with the engine. The mechanism operates hydraulically and is affected by the fuel pressure in the sump of the injection pump. There is also provided a hydraulic control valve mechanism which permits varying amounts of fuel to flow back from the sump to the low pressure side of the fuel delivery pump, thereby changing the injection timing. A primary control valve adjusts the sump pressure on the basis of engine speed while a secondary control valve adjusts the sump pressure on the basis of engine temperature in order to adapt the timing of fuel injection to engine starting and engine warm-up.
    Type: Grant
    Filed: May 4, 1981
    Date of Patent: August 2, 1983
    Assignee: Robert Bosch GmbH
    Inventors: Gerald Hofer, Karl Konrath, Franz Eheim, Otmar Weiss, Edgar Schmitt, Werner Faupel, Edgar Gotz
  • Patent number: 4393835
    Abstract: An rpm governor is proposed, in which intervention into the regulation process can be made directly via a magnet, so that the degree of proportionality, particularly with isostatic governors, can be lowered to a minimum.
    Type: Grant
    Filed: December 28, 1981
    Date of Patent: July 19, 1983
    Assignee: Robert Bosch GmbH
    Inventors: Franz Eheim, Gerald Hofer