Patent classifications
B62D5/08
HYDRAULIC ARRANGEMENT FOR HYBRID PRIORITY VALVE
A hydraulic arrangement for distributing a fluid in pressure coming from a source among multiple hydraulic units of a work vehicle. At least one of the hydraulic units provides an electronic load sensing signal and of the hydraulic units provides a hydraulic load sensing signal. The hydraulic arrangement includes a priority valve configured to divide the flow of fluid between the hydraulic units. The priority valve and source are hydraulically controlled by a first hydraulic load sensing signal resulting as the greatest of a plurality of hydraulic load pressure signals taken from the hydraulic unit. The hydraulic arrangement also includes a conversion unit configured to transform an electronic load sensing signal of at least one of the hydraulic units in an equivalent hydraulic load sensing signal so as to define the first hydraulic load sensing signal.
PRIORITY FLOW CONTROL VALVE
A throttle check valve includes: a poppet valve body that has an orifice formed at one end and has a hole portion formed at a side portion; a plug that has a tubular shape to surround the poppet valve body, and functions as a valve seat to come into contact with the poppet valve body; and a spring that biases the poppet valve body and the plug functioning as the valve seat in directions to come into contact with each other. When the spool is at the second position, the plug forming the distal end portion of the spool and the plug arranged in the housing come into contact with each other. The plug is provided with a protruding portion that comes into contact with the poppet valve body.
PRIORITY FLOW CONTROL VALVE
A throttle check valve includes: a poppet valve body that has an orifice formed at one end and has a hole portion formed at a side portion; a plug that has a tubular shape to surround the poppet valve body, and functions as a valve seat to come into contact with the poppet valve body; and a spring that biases the poppet valve body and the plug functioning as the valve seat in directions to come into contact with each other. When the spool is at the second position, the plug forming the distal end portion of the spool and the plug arranged in the housing come into contact with each other. The plug is provided with a protruding portion that comes into contact with the poppet valve body.
Hydraulic steering unit
A hydraulic steering unit (1) is described, said hydraulic steering unit (1) comprising a supply port arrangement having a pressure port (P) connected to a main flow path (3) and a tank port (T) connected to a tank flow path (4), a working port arrangement having a left working port (L) connected to a left working flow path (5) and a right working port (R) connected to a right working flow path (6), a bridge arrangement (14) of variable orifices having a first left orifice (A2L) connected to the main flow path (3) and to the left working flow path (5), a first right orifice (A2R) connected to the main flow path (3) and to the right working flow path (6), a second left orifice (A3L) connected to the left working flow path (5) and to the tank flow path (4), and a second right orifice (A3R) connected to the right working flow path (6) and to the tank flow path (4). Such a hydraulic steering unit should be operated together with a pressure source of fixed displacements. To this end an idle flow path (15) branches off the main flow path (3), wherein a variable idle orifice (An) is arranged in the idle flow path (15), the idle orifice (An) being open in neutral position and closing out of neutral position.
HYDRAULIC STEERING UNIT
A hydraulic steering unit (1) is described comprising a supply port arrangement having a pressure port (P) connected to a main flow path (2) and a tank port (T) connected to a tank flow path (3), a working port arrangement having a left working port (L) connected to a left working flow path (9) and a right working port (R) connected to a right working flow path (10), a first bridge arrangement (15a, 15b) of variable orifices having a first left orifice (A2L) connected to the main flow path (2) and to a first left connecting point (16) at the left working flow path (9), a first right orifice (A2R) connected to the main flow path (2) and to a first right connecting point (17) at the right working flow path (10), a second left orifice (A3L) connected to the first left connecting point (16) at the left working flow path (9) and to the tank flow path (3), and a second right orifice (A3R) connected to the first right connecting point (17) at the right working flow path (10) and to the tank flow path (3). It should be possible to change the steering characteristics of such a steering unit. This is achieved by at least a second bridge arrangement (20a, 20b) of variable orifices having a third left orifice (A2L) connected to the main flow path (2) and to a second left connecting point (21) at the left working flow path (9), a third right orifice (A2R) connected to the main flow path (2) and to a second right connecting point (22) at the right working flow path (10), a fourth left orifice (A3L) connected to the second left connecting point (21) at the left working flow path (9) and to the tank flow path (3), and a fourth right orifice (A3R) connected to the second right connecting point (22) at the right working flow path (10) and to the tank flow path (3), wherein the first bridge arrangement (15a, 15b) and the second bridge arrangement (20a, 20b) have different steering characteristics, and by selection means (23) connecting at least one of the bridge arrangements (15a, 15b; 20a, 20b) between the pressure port (P) and the working port arrangement.
END-OF-TRAVEL RELIEF IN A POWER STEERING SYSTEM
An improved power steering assembly is provided. The power steering assembly includes an end-of-travel mechanism and a valve cartridge that is actuated by left and right actuator rings of the end-of-travel mechanism, the actuator rings extending partially around an output shaft. The actuator rings can be individually set for the desired end-of-travel relief to limit the maximum system pressure when the steering assembly approaches the desired axle stop setting. The valve cartridge provides an end-of-travel function and a pressure relief function and is in fluid communication with the left and right pressure chambers to recirculate hydraulic fluid in the event of a power off condition.
Hydraulic steering unit
A hydraulic steering unit (1) is described comprising a supply port arrangement having a pressure port (P) connected to a main flow path (2) and a tank port (T) connected to a tank flow path (3), a first working port arrangement having a first left working port (L1) connected to a first left working flow path (4) and a first right working port (R1) connected to a first right working flow path (5), a variable first left orifice (A2L) connected to the main flow path (2) and to the first left working flow path (4), a variable first right orifice (A2R) connected to the main flow path (2) and to the first right working flow path (5), a variable second left orifice (A3L) connected to the first left working flow path (4) and to the tank flow path (3), a variable second right orifice (A3R) connected to the first right working flow path (5) and to the tank flow path (3), and a second working port arrangement having a second left working port (12) connected to a second left working flow path (9) and a second right working port (R2) connected to a second right working flow path (10), wherein the variable first left orifice (A2L) is connected to the second left working flow path (9) and the variable first right orifice (A2R) is connected to the second right working flow path (10).
Hydraulic steering unit
A hydraulic steering unit (1) is described comprising a supply port arrangement having a pressure port (P) connected to a main flow path (2) and a tank port (T) connected to a tank flow path (3), a first working port arrangement having a first left working port (L1) connected to a first left working flow path (4) and a first right working port (R1) connected to a first right working flow path (5), a variable first left orifice (A2L) connected to the main flow path (2) and to the first left working flow path (4), a variable first right orifice (A2R) connected to the main flow path (2) and to the first right working flow path (5), a variable second left orifice (A3L) connected to the first left working flow path (4) and to the tank flow path (3), a variable second right orifice (A3R) connected to the first right working flow path (5) and to the tank flow path (3), and a second working port arrangement having a second left working port (12) connected to a second left working flow path (9) and a second right working port (R2) connected to a second right working flow path (10), wherein the variable first left orifice (A2L) is connected to the second left working flow path (9) and the variable first right orifice (A2R) is connected to the second right working flow path (10).
HYDRAULIC CIRCUIT
A hydraulic circuit, in particular to a hydraulic steering circuit for steering at least one vehicle axle, the hydraulic circuit including a first fluid path having a first end and a second end and providing fluid communication or selective fluid communication between the first end and the second end of the first fluid path; and a second fluid path providing fluid communication or selective fluid communication between the first end of the first fluid path and the second end (2) of the first fluid path, in parallel to the first fluid path or to a section thereof. In some aspects, the first fluid path includes a first hydraulic displacement unit; and the second fluid path includes at least a first proportional bypass control valve for controlling a bypass fluid flow in the second fluid path. The hydraulic steering circuit may be part of a driveline for a vehicle.
HYDRAULIC CIRCUIT
A hydraulic circuit, in particular to a hydraulic steering circuit for steering at least one vehicle axle, the hydraulic circuit including a first fluid path having a first end and a second end and providing fluid communication or selective fluid communication between the first end and the second end of the first fluid path; and a second fluid path providing fluid communication or selective fluid communication between the first end of the first fluid path and the second end (2) of the first fluid path, in parallel to the first fluid path or to a section thereof. In some aspects, the first fluid path includes a first hydraulic displacement unit; and the second fluid path includes at least a first proportional bypass control valve for controlling a bypass fluid flow in the second fluid path. The hydraulic steering circuit may be part of a driveline for a vehicle.