1. A hydraulic two-way valve comprising:
a pump connection configured to be connected to a hydraulic pump;
a tank connection; and
a first working connection and a second working connection configured to be connected to a hydraulic cylinder of a lifting mechanism of an agricultural vehicle; wherein:
in a first switching position, the pump connection, the tank connection, the first working connection and the second working connection are shut off;
in a second switching position, the pump connection is connected to the first working connection and the tank connection is connected to the second working connection;
in a third switching position, the pump connection is connected to the second working connection and the tank connection is connected to the first working connection;
in a fourth switching position, the first working connection and the second working connection are connected to the tank connection, and the pump connection is shut off; and
in a fifth switching position the tank connection is connected to the second working connection, and the pump connection and the first working connection are shut off.
2. The hydraulic two-way valve according to claim 1, further comprising a valve slide configured to move linearly to pass through the switching positions in a sequence:
third switching position;
first switching position;
fifth switching position;
second switching position; and
fourth switching position.
3. The hydraulic two-way valve according to claim 2, further comprising:
a load pressure connection configured to be connected to a pressure regulator of the hydraulic pump, wherein the load pressure connection is connected to the pump connection in the second and the third switching positions and the load pressure connection is connected to the tank connection in the first, the fourth and the fifth switching positions.
4. The hydraulic two-way valve according to claim 3, wherein the two-way valve is configured as a proportional valve, in which all fluid connections continuously open and close.
5. The hydraulic two-way valve according to claim 4, wherein between the second and the fourth switching positions the valve slide passes through a first transition region, in which the pump connection is connected to the first working connection and a fluid connection between the first working connection and the tank connection is shut off.
6. The hydraulic two-way valve according to claim 5, wherein between the first transition region and the fourth switching position the valve slide passes through a second transition region, in which a fluid connection between the tank connection and the first working connection continuously opens.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for correcting the prediction of values of signals with time variation disturbed by various uncontrollable systematic effects, comprising the following steps for the correction of the predictions of a parameter included in a received signal and varying in time:
constructing a history of the prediction error based on a first batch of values (E1) estimated a posteriori during a determined time period, called restored values, by comparing these restored values to a batch of values previously predicted for the same determined time period,
analyzing predicted time-oriented series of prediction errors by a method for processing the signal and isolating contributions of the systematic effects, and
extrapolating a new prediction time period of the behavior of the contributions of the systematic effects identified during the time period concerned (E1) and correction of the predictions using duly extrapolated values.
2. The method as claimed in claim 1, wherein the signal processing method is a Fourier or wavelet transform.
3. The method as claimed in claim 1, wherein the prediction time periods are mutually overlapping.
4. The method as claimed in claim 1, wherein the signals are received from a radio navigation satellite for the correction of the orbit prediction information for these satellites and their reference clock.