A drive arrangement for a motor vehicle flap including a gas pressure element, the gas pressure element has an outwardly sealed cylinder and a piston moveable in the cylinder interior along the cylinder axis and subdivides the cylinder interior into two sub-chambers, the gas pressure element has a first drive connection connected to the cylinder, and a second drive connection connected to the piston, the cylinder filled with a fluid and the piston has an overflow channel arrangement to create a balancing flow between the two sub-chambers to balance a pressure drop between the two sub-chambers. The piston is assigned a switchable valve arrangement which, depending on the pressure drop between the two sub-chambers, to create different through-flow states differing the cross section of the overflow channel arrangement. Upon exceeding a predetermined threshold for the pressure drop, the valve arrangement switches to change the cross section of the overflow channel arrangement.

A drive arrangement for a motor vehicle flap including a gas pressure element, the gas pressure element has an outwardly sealed cylinder and a piston moveable in the cylinder interior along the cylinder axis and subdivides the cylinder interior into two sub-chambers, the gas pressure element has a first drive connection connected to the cylinder, and a second drive connection connected to the piston, the cylinder filled with a fluid and the piston has an overflow channel arrangement to create a balancing flow between the two sub-chambers to balance a pressure drop between the two sub-chambers. The piston is assigned a switchable valve arrangement which, depending on the pressure drop between the two sub-chambers, to create different through-flow states differing the cross section of the overflow channel arrangement. Upon exceeding a predetermined threshold for the pressure drop, the valve arrangement switches to change the cross section of the overflow channel arrangement.

A flow controller that changes the flow rate of air exhausted from an air cylinder in mid-stroke includes a first switching valve displaced from a first position to a second position under the effect of pilot air, and causing one port of the air cylinder to communicate with a first channel at the first position, exhausting air exhausted from the one port of the air cylinder while reducing the flow rate of the air using a first regulating valve at the second position. Since the pilot air is taken into the first switching valve from a second channel in a system different from the system of the first channel, a second regulating valve can be adjusted without being affected by the degree of opening of the first regulating valve.

A flow controller that changes the flow rate of air exhausted from an air cylinder in mid-stroke includes a first switching valve displaced from a first position to a second position under the effect of pilot air, and causing one port of the air cylinder to communicate with a first channel at the first position, exhausting air exhausted from the one port of the air cylinder while reducing the flow rate of the air using a first regulating valve at the second position. Since the pilot air is taken into the first switching valve from a second channel in a system different from the system of the first channel, a second regulating valve can be adjusted without being affected by the degree of opening of the first regulating valve.

A hydraulic system in a work machine includes a travel operation device provided in a pilot oil path between a hydraulic pump a travel pump and including an operation member and configured to generate a pilot pressure supplied via the pilot oil path and an additional pilot pressure in accordance with an operation amount of the operation member. The travel pump is to control a flow direction of hydraulic oil supplied to a travel motor based on the pilot pressure and the additional pilot pressure. A pressure selection valve is provided in a first coupling oil path to select a selected pressure from the pilot pressure and the additional pilot pressure to apply the selected pressure to the pilot hydraulic oil in the second coupling oil path. A pressure adjustment valve is provided in a second coupling oil path to control the selected pressure to be an adjusted pilot pressure.

In the case of an incorrect polarity of connectors in hydraulic networks, a switching device is provided, and formed with a connector part, a valve body, a switching part displaced axially in the valve body within limits, a base part and a top part. Wherein cooperating annular chambers for the conducting of a working fluid are formed in the region of an inner surface of the valve body and an outer surface of the switching part. Annular surfaces (A2, A3, A5, A7) are acted upon with pressurized fluid on the switching part towards the top part and annular surfaces (A1, A4, A6) of the switching part are acted upon towards the base part have a following size relations when there is a permanent fluidic connection of the annular chambers:

A2=A3>0.5×A1;

A4>A5+A7;

A3+A7>A4+A6;

A1=2A2−A4+A5−A6+A7

A gangway comprises a fixed platform and a support structure connected to the fixed platform in a manner that allows the support structure to rotate with respect to the fixed platform between a raised stowed position and a lowered deployed position. A self-raising assembly is operative to rotate the support structure from the deployed position to the stowed position. The self-raising assembly includes at least one fluid actuated cylinder connected between the fixed platform and a distal end of the support structure. A raising actuator is usable by an operator to cause operation of the cylinder in a manner that rotates the support structure toward the stowed position.

A gangway comprises a fixed platform and a support structure connected to the fixed platform in a manner that allows the support structure to rotate with respect to the fixed platform between a raised stowed position and a lowered deployed position. A self-raising assembly is operative to rotate the support structure from the deployed position to the stowed position. The self-raising assembly includes at least one fluid actuated cylinder connected between the fixed platform and a distal end of the support structure. A raising actuator is usable by an operator to cause operation of the cylinder in a manner that rotates the support structure toward the stowed position.

A system for reducing loader arm movement during operation of a work vehicle includes a sensor configured to capture data indicative of an angle of a loader arm of the vehicle relative to the vehicle chassis. A controller of the disclosed system is configured to control the operation of a valve of the vehicle such that fluid from a pump of the vehicle is supplied to first and second chambers of a fluid-driven actuator of the vehicle to initiate a ride control mode. Moreover, the controller is configured to monitor the angle of the loader arm relative to the chassis based on the data captured by the sensor. In addition, the controller is configured to control the operation of the pump based on the monitored angle after the ride control mode has been initiated

A system for reducing loader arm movement during operation of a work vehicle includes a sensor configured to capture data indicative of an angle of a loader arm of the vehicle relative to the vehicle chassis. A controller of the disclosed system is configured to control the operation of a valve of the vehicle such that fluid from a pump of the vehicle is supplied to first and second chambers of a fluid-driven actuator of the vehicle to initiate a ride control mode. Moreover, the controller is configured to monitor the angle of the loader arm relative to the chassis based on the data captured by the sensor. In addition, the controller is configured to control the operation of the pump based on the monitored angle after the ride control mode has been initiated