Robert Boschgmbh

Werner Schumacher

Horst Hesse

Holger Lueues

Hubert Mohaupt

Heinrich Lodige

Roland Schempp

Manfred Hauser

Gunther Schwerin

Heinrich Kochendorfer

Hartmut Sandau

Winfried Arnold

Friedrich-Wilhelm Hofer

Hartmut Sandau, Deceased

Rainer Trucksess

Raimund Skambraks

Arnold Winfried

An electro-hydraulic control device (,) for a hydraulic servo motor for controlling a volume flow is proposed, which is embodied as a 4/2 valve module. A blocking valve in accordance with seat valve technology between a motor connection (B) and a return flow (R) form a lowering element (,), while the associated unblocking member (,) is designed as a longitudinal slide (,), which controls the connection between an inflow connection (P) and a motor connection (A) and is actuated by a proportional magnet (,). After unblocking the blocking valve, its seat valve body (,) is mechanically taken along by the longitudinal slide (,), and the two volume flows are proportionally controlled via the lowering element (,) and the lifting element (,), so that a large switching capacity is achieved along with a construction with few leaks.

Electrohydraulic control device

A hydraulic circuit in a monoblock structure for lifting and lowering a load has at least two electromagnetically actuatable proportional distributing valve elements, a check valve, a pressure balance for load-independent lifting of the load as an input element, a housing accommodating at least some of the elements and having at least one pump connection, at least one consumer connection, and at least one return connection, the proportional distributing valve elements being disposed parallel to one another, electromagnetic drives seated side-by-side on a same side and at a same height, the pressure balance having a piston which is disposed coaxially next to a longitudinal slide of a first one of the proportional distributing valve elements in a bore that guides and supports both the valve elements, the longitudinal slide of the first proportional distributing valve elements being spring-loaded, and at least one component for adjusting a prestressing and bracing of a spring on the housing of a control penetrating the piston of the pressure balance.

Hydraulic control in monoblock structure for lifting and lowering a load

In a device for controlling a slip and a traction force of an implement coupled to a tractor by a hoisting unit, a slip contol system is combined with a traction force control system. The control device includes a drive speed sensor connected to the tractor and an acceleration sensor positioned on the tractor. A measured acceleration value is compared in a comparator circuit with an adjusted output signal of the drive speed sensor, and an actual slip value is determined by integration from an acceleration difference signal. The actual slip value is used for adjusting a control value generated in the traction force control system to control a position of the hoisting unit.

Control device for position-control of implement coupled to an

An electro-hydraulic arrangement regulating the lifting mechanism actuatable by a hydraulic motor, on an agricultural working vehicle having a driven wheel, comprises a plurality of sensors including a position sensor forming an actual value position signal, a force sensor forming an actual value force sensor, and an additional sensor forming an actual value slippage signal dependent on slippage of the driven wheel, a nominal value transmitter, a first summation point connected with the additional sensor and with the force sensor so as to obtain the slippage-dependent signal and the actual value force signal therefrom and to produce an output signal, a mixing device having a first input connected with the first summation point and for receiving the output signal and a second input connected with the position sensor for receiving the actual value position signal and producing an output signal, and a second summation point connected with the mixing device for receiving the output signal of the mixing device and also connected with the nominal value transmitter for receiving a signal from the latter so as to form a regulating deviation for the lifting mechanism.

Agricultural working vehicle with electro-hydraulic for regulating

A control arrangement for a hydraulic motor has an adjustable pressure medium supply device with a container, an unblockable check valve with a control connection, a plurality of chambers including a supply chamber, a motor chamber, first and second return chambers, and a control chamber, a control slider displaceable relative to the chambers, wherein a control conduit extends from the supply device and leads to the control chamber, a first pressure control member is arranged on the control slider so that in a lowered position of the latter the first pressure controlling member is located between the control chamber and the second return chamber and the control slider in its raised position blocks the control chamber, and a second pressure controlling member located between the control chamber and the motor chamber and opening into the latter.

Control arrangement for hydraulic motor

A control arrangement for a hydraulically operated load lifting and lowering device includes precontrolled first valve means controlling flow of fluid from a source under pressure to a return conduit leading to a tank or to a working conduit leading to the device and a closer block in the working conduit, including a piston controlling flow of pressure fluid from the working conduit into the device, respectively flow of pressure fluid out of the device into the return conduit downstream of the piston. A throttle is arranged in the return conduit to produce upstream of the throttle a pressure acting on the piston but not on the slide of the first valve means, whereby without increasing the neutral fluid circulation pressure a uniform lowering of the load independent of the magnitude thereof may be obtained.

Control arrangement for a hydraulically operated device

A spool valve arrangement includes a housing having a flow-through passage formed with a fluid-admitting inlet and a pair of fluid-discharging outlets, and a pair of pressure-relief chambers each associated with a respective outlet for relieving pressure thereat. The arrangement further comprises a spool slide having respective ends each facing into one of the pressure-relief chambers and also has a pair of lands. The spool slide is mounted in the passage for movement from a neutral position in which the lands prevent communication between the inlet and the outlets and in which communication is also prevented between the latter and their associated chambers, towards operative positions in which pressure relief is permitted at a respective one of the outlets so that pressurized fluid escaping from one outlet into its associated chamber acts on the respective end of the slide which faces the latter and tends to accelerate the movement of the spool slide towards one of its operative positions. Attenuation elements, each formed with a deflecting surface positioned to be impinged by the pressurized fluid escaping into the respective pressure-relief chamber, dampens the acceleration of the spool slide and slows the movement of the latter towards the respective operative positions.

Growing community of inventors

Asperg, Germany

Werner Schumacher