Patents by Inventor Armin Lang

Armin Lang 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: 4068678
    Abstract: A valve device having a pressure operable valve piston, particularly for booster steering systems, to selectively control pressure flow to a consumer device such as a hydraulic servomotor in order to permit use of a reserve pump in event of failure of a main pump. The valve in a neutral position blocks the output of both pumps to a sump but is responsive to a first increase in flow rate beyond a predetermined limit to shunt flow from the reserve pump to a sump. Upon further increase in flow rate the valve piston moves to a position to also shunt part of the output from the main pump to a sump. Differential pressure acting on a valve piston effects shifting and means are provided to vary the differential pressure required to shift the valve piston so that a greater differential pressure is needed for the shifting of the valve piston for the partial shunting of the main pump output. Signal means is actuated by movement of the valve piston to apprise a vehicle driver that the valve device is operative.
    Type: Grant
    Filed: April 20, 1976
    Date of Patent: January 17, 1978
    Assignee: Zahnradfabrik Friedrichshafen AG
    Inventors: Armin Lang, Rolf Fassbender
  • Patent number: 4028997
    Abstract: A fluid power assist type of vehicle steering system having a controlled servo motor assembly operated through a control circuit, and interconnected with the steering linkage, is provided with an auxiliary servo motor assembly through which pressure regulation is effected to prevent vibration otherwise amplified by feedback pressure signals. Differential pressure actuated pilot valves control the supply and return of pressurized fluid to and from the auxiliary servo motor assembly in response to differences between opposing pressures of the servo motor assemblies to regulate only the pressure chambers of the auxiliary servo motor assembly.
    Type: Grant
    Filed: May 2, 1975
    Date of Patent: June 14, 1977
    Assignee: Zahnradfabrik Friedrichshafen AG
    Inventor: Armin Lang
  • Patent number: 4020748
    Abstract: A valve piston in an automotive power-steering system has a pair of inner peripheral grooves, defined by confronting lands of adjoining piston heads, normally communicating with the high-pressure side of an oil pump via symmetrical branch channels and with the low-pressure side of that pump via a common return channel. The piston also has a pair of outer peripheral grooves, normally cut off from the adjoining inner grooves, connected to opposite cylinder chambers of a hydraulic servomotor. The inner grooves communicate with a pair of axial piston bores receiving fixed or spring-loaded plungers for exerting a counteracting hydraulic pressure upon the piston upon a displacement thereof from its centered position, such displacement also opening the path from one branch channel via the corresponding inner groove and the adjoining outer groove to a corresponding servomotor chamber.
    Type: Grant
    Filed: September 3, 1974
    Date of Patent: May 3, 1977
    Assignee: Zahnradfabrik Friedrichshafen AG
    Inventor: Armin Lang
  • Patent number: 3989120
    Abstract: The invention provides a compact control valve for double acting steering system servomotors utilizing a housing and control valve therein with coacting lands and passage means effecting a transfer of fluid from one pressure chamber to the other of a single piston rod servomotor. Such transfer is in response to automatic straightening of the wheels of a vehicle by road contact after they have been turned to effect steering. In particular, since the servomotor pressure chambers are unequal in volume due to the bulk of the piston rod passing through only one chamber, some volume compensation for shunting of the fluid between chambers is required due to excess of fluid in going to the smaller volume chamber from the larger volume chamber, and deficit of fluid when transferring in the opposite direction.
    Type: Grant
    Filed: April 22, 1975
    Date of Patent: November 2, 1976
    Assignee: Zahnradfabrik Friedrichshafen AG
    Inventors: Armin Lang, Karl-Heinz Liebert
  • Patent number: 3968733
    Abstract: A steering shaft, linked with the dirigible wheels of an automotive vehicle and coupled with a hydraulic servomotor for rotation in either direction under the control of a main valve, has two abutments for alternately opening two normally closed ancillary valves in respective limiting positions of the shaft, these ancillary valves being inserted in branches of two feeder lines extending from the main valve to respective cylinder chambers of the servomotor. Either ancillary valve, when opened, connects one cylinder compartment of a differential valve to the feeder line then under low pressure, the other compartment of that differential valve being connected to a supply conduit whereby a pressure difference is created across a spring-loaded piston in that valve whose two compartments are interconnected by a bleeder line. The piston, upon being displaced by this pressure against its spring force, vents the supply conduit to the low-pressure side of the fluid source to arrest the servomotor.
    Type: Grant
    Filed: May 15, 1974
    Date of Patent: July 13, 1976
    Assignee: Zahnradfabrik Friedrichshafen AG
    Inventors: Armin Lang, Falk Kurz, Wolfgang Walter
  • Patent number: 3952771
    Abstract: Piston type hydraulically balanced relief valves are disclosed except for one modification, utilizing pilot valves carried completely within the bodies of the relief valves or relief valve cartridges and wherein a single spring serves for closure of the relief valve and the respective pilot valve. All pilot valves are thus biased by a single spring primarily due to differential upstream and downstream areas both exposed to inlet pressure but with the upstream area larger and dominating. Accordingly, a single light biasing spring can suffice because of the reduced net opening force required, upon a predetermined rise in inlet pressure. The constructions afforded by such an arrangement are more compact than conventional pilot controlled relief valves wherein the relief and pilot valves are closed by separate and relatively heavy springs. Further, the advantage of the sensitivity of pilot controlled relief valves is realized together with effective damping and minimum control flow dependency.
    Type: Grant
    Filed: May 29, 1975
    Date of Patent: April 27, 1976
    Assignee: Zahnradfabrik Friedrichshafen AG
    Inventor: Armin Lang