US 11,939,739 B2
Hydraulic arrangement
Erik Westergaard, Nordborg (DK); and Henrik Hauge, Nordborg (DK)
Assigned to DANFOSS POWER SOLUTIONS INC., Ames, IA (US)
Filed by Danfoss Power Solutions Inc., Ames, IA (US)
Filed on Apr. 9, 2021, as Appl. No. 17/226,303.
Claims priority of application No. 102020110187.2 (DE), filed on Apr. 14, 2020.
Prior Publication US 2021/0317638 A1, Oct. 14, 2021
Int. Cl. E02F 3/34 (2006.01); E02F 3/43 (2006.01); E02F 9/20 (2006.01); E02F 9/22 (2006.01)
CPC E02F 3/3411 (2013.01) [E02F 3/432 (2013.01); E02F 9/2029 (2013.01); E02F 9/2203 (2013.01); E02F 9/2228 (2013.01); E02F 9/2296 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of operating a hydraulic arrangement comprising a mounting base, a boom that is pivotably arranged on the mounting base, and a Z-kinematics that is arranged on the boom, the Z-kinematics being designed and arranged to tilt a tool attachment device, the tool attachment device being pivotably arranged on the boom,
wherein the boom is moved by at least a lifting hydraulic piston that is connected to the boom and to the mounting base,
and wherein the Z-kinematics is moved by at least a tilting hydraulic piston that is connected to a lever of the Z-kinematics and to the mounting base,
wherein on application of an input control command for changing the position of the lifting hydraulic piston, an initial compensation command is automatically generated and applied to the tilting hydraulic piston, to essentially maintain the attitude of the tool attachment device, where the initial compensation command is generated based on the input control command for the lifting hydraulic piston, using a mathematical model of the hydraulic arrangement and without using input from an angle sensor associated with the tool attachment device.
 
18. A method of operating a hydraulic arrangement comprising a mounting base, a boom that is pivotably arranged on the mounting base, and a Z-kinematics that is arranged on the boom, the Z-kinematics being designed and arranged to tilt a tool attachment device, the tool attachment device being pivotably arranged on the boom,
wherein the boom is moved by at least a lifting hydraulic piston that is connected to the boom and to the mounting base,
and wherein the Z-kinematics is moved by at least a tilting hydraulic piston that is connected to a lever of the Z-kinematics and to the mounting base,
wherein on application of an input control command for changing the position of the lifting hydraulic piston, a compensation command is automatically generated and applied to the tilting hydraulic piston, to essentially maintain the attitude of the tool attachment device, where the compensation command is generated based on the input control command for the lifting hydraulic piston, using a mathematical model of the hydraulic arrangement,
wherein the Z-kinematics comprises a rocking lever and a connecting lever, where the rocking lever is pivotably attached to the boom at a middle section, to the tilting hydraulic piston at a first end section, and to the connecting lever at a second end section thereof; and wherein the connecting lever is connected to the rocking lever at a first end section and to the tool attachment device at a second end section thereof,
wherein the method calculates an angle ϕ1 between a line OE, connecting points O and E, and a line Ej, connecting points E and J, using a formula

OG Complex Work Unit Math
where O is a hinging point of the boom and the mounting base, E is a hinging point of the boom and the tool attachment device, and J is a hinging point of the connecting lever of the Z-kinematics and the tool attachment device.
 
19. A method of operating a hydraulic arrangement comprising a mounting base, a boom that is pivotably arranged on the mounting base, and a Z-kinematics that is arranged on the boom, the Z-kinematics being designed and arranged to tilt a tool attachment device, the tool attachment device being pivotably arranged on the boom,
wherein the boom is moved by at least a lifting hydraulic piston that is connected to the boom and to the mounting base,
and wherein the Z-kinematics is moved by at least a tilting hydraulic piston that is connected to a lever of the Z-kinematics and to the mounting base,
wherein on application of an input control command for changing the position of the lifting hydraulic piston, a compensation command is automatically generated and applied to the tilting hydraulic piston, to essentially maintain the attitude of the tool attachment device, where the compensation command is generated based on the input control command for the lifting hydraulic piston, using a mathematical model of the hydraulic arrangement,
wherein the Z-kinematics comprises a rocking lever and a connecting lever, where the rocking lever is pivotably attached to the boom at a middle section, to the tilting hydraulic piston at a first end section, and to the connecting lever at a second end section thereof; and wherein the connecting lever is connected to the rocking lever at a first end section and to the tool attachment device at a second end section thereof,
wherein the method calculates an angle ϕ2 between a line OJ, connecting points O and J, and a line EJ, connecting points E and J, using a formula

OG Complex Work Unit Math
where O is a hinging point of the boom and the mounting base, E is a hinging point of the boom and the tool attachment device, and J is a hinging point of the connecting lever of the Z-kinematics and the tool attachment device.
 
20. A method of operating a hydraulic arrangement comprising a mounting base, a boom that is pivotably arranged on the mounting base, and a Z-kinematics that is arranged on the boom, the Z-kinematics being designed and arranged to tilt a tool attachment device, the tool attachment device being pivotably arranged on the boom,
wherein the boom is moved by at least a lifting hydraulic piston that is connected to the boom and to the mounting base,
and wherein the Z-kinematics is moved by at least a tilting hydraulic piston that is connected to a lever of the Z-kinematics and to the mounting base,
wherein on application of an input control command for changing the position of the lifting hydraulic piston, a compensation command is automatically generated and applied to the tilting hydraulic piston, to essentially maintain the attitude of the tool attachment device, where the compensation command is generated based on the input control command for the lifting hydraulic piston, using a mathematical model of the hydraulic arrangement,
wherein the Z-kinematics comprises a rocking lever and a connecting lever, where the rocking lever is pivotably attached to the boom at a middle section, to the tilting hydraulic piston at a first end section, and to the connecting lever at a second end section thereof; and wherein the connecting lever is connected to the rocking lever at a first end section and to the tool attachment device at a second end section thereof,
wherein the method calculates an angle ϕ3 between a line OJ, connecting points O and J, and a line OE, connecting points O and E, using a formula

OG Complex Work Unit Math
where O is a hinging point of the boom and the mounting base, E is a hinging point of the boom and the tool attachment device, and J is a hinging point of the connecting lever of the Z-kinematics and the tool attachment device.