Patents by Inventor Harald Hellmann

Harald Hellmann 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: 5460438
    Abstract: A damping device for pressure pulsations having a first hollow chamber for receiving hydraulic pressure fluid and a second hollow chamber. An elastic metal diaphragm that divides the second hollow chamber hermetically from the first hollow chamber. The second hollow chamber is evacuated, so that in the event that the metal diaphragm should possibly leak, no air can get into the hydraulic pressure fluid. The damping device can be used in hydraulic brake systems having a master cylinder and in other hydraulic systems.
    Type: Grant
    Filed: April 6, 1994
    Date of Patent: October 24, 1995
    Assignee: Robert Bosch GmbH
    Inventors: Harald Hellmann, Wolfgang Maisch, Robert Mergenthaler
  • Patent number: 5255963
    Abstract: A known hydraulic vehicle brake system has an anti-skid valve assembly. By this assembly, the at least one wheel brake can be temporarily disconnected from the master brake cylinder and connected to one inlet of a return pump, which furnishes the quantities of pressure fluid flowing out of the wheel brakes both to a damper chamber and, via a damper throttle, to the master brake cylinder and/or the at least one wheel brake. The disadvantage is that all of the pressure fluid pumped by the return pump can sometimes reach the master brake cylinder, disagreeably moving the brake pedal in the direction of its outset position. This can annoy a driver and should be avoided. The improved vehicle brake system has a valve, which in anti-skid operation can be blocked, located between the damper throttle and the master brake cylinder and also has a bypass throttle bypassing the valve. As a result, during anti-skid operation, the brake pedal is not displaced to such an annoying extent.
    Type: Grant
    Filed: August 1, 1990
    Date of Patent: October 26, 1993
    Assignee: Robert Bosch GmbH
    Inventors: Rainer Altmann, Rainer Lauer, Guenther Schmidt, Kasimir Stromski, Anton V. Zanten, Alfred Sigl, Harald Hellmann, Karl Veil, Hans-Joerg Fees, Wolf-Dieter Jonner, Reinhard Gutzeit
  • Patent number: 5112117
    Abstract: A vehicle brake system comprising a hydraulically controllable 2/2-way valve, which has a first control inlet and a second control inlet. The first control inlet receives its control pressure from a first brake pressure source, while the second control inlet contrarily receives its control pressure from a second brake pressure source, such as a so-called return pump apparatus. The vehicle brake system can be used in passenger cars, vans, small buses, and small trucks as well as motor cycles.
    Type: Grant
    Filed: February 7, 1991
    Date of Patent: May 12, 1992
    Assignee: Robert Bosch GmbH
    Inventors: Rainer Altmann, Rainer Lauer, Guenther Schmidt, Kasimir Stromski, Anton van Zanten, Harald Hellmann, Karl Veil, Hans-Joerg Fees, Wolf-Dieter Jonner, Reinhard Gutzeit
  • Patent number: 5039176
    Abstract: The brake system has at least one valve assembly, disposed between a master brake cylinder and at least one wheel for controlling the brake pressure during anti-skid operation. A pump is also provided for pumping pressure fluid, withdrawn from the wheel brake during a pressure reduction phase, to the master brake cylinder. A valve assembly comprising two parallel-connected 2/2-way valves is provided between the master brake cylinder and the pressure control valve assembly. During anti-skid operation, the first 2/2-way valve can be switched into a position (b) that throttles the flow of pressure fluid both from the pump to the master brake cylinder and from the master brake cylinder to the wheel brake. As a result, pulsations at the brake pedal of the master brake cylinder are largely avoided.
    Type: Grant
    Filed: August 1, 1990
    Date of Patent: August 13, 1991
    Assignee: Robert Bosch GmbH
    Inventors: Harald Hellmann, Heinz Siegel