A vehicle fluid exchange machine is disclosed that allows the technician to control the flow into the vehicle or stand-alone cooling or hydraulic system either manually or automatically based on a safe working pressure for the vehicle. If the vehicle's cooling system can handle a higher pressure for example, the technician may adjust the machine's flow to a flow rate consistent with the higher pressure rating while monitoring the pressure across the system. The default setting for the air injection process is automatic, but can also be switched to manual by the technician.

A vehicle fluid exchange machine is disclosed that allows the technician to control the flow into the vehicle or stand-alone cooling or hydraulic system either manually or automatically based on a safe working pressure for the vehicle. If the vehicle's cooling system can handle a higher pressure for example, the technician may adjust the machine's flow to a flow rate consistent with the higher pressure rating while monitoring the pressure across the system. The default setting for the air injection process is automatic, but can also be switched to manual by the technician.

A gasket device for a pneumatic valve system, in particular of a commercial vehicle, comprises gasket part being adapted to be inserted into at least a groove of a contact face of a first casing part, e.g. an adapter, the gasket part comprising at least one gasket chamber for sealingly connecting device channels of mounted casing parts; a body part being adapted to be received in a valve seat of the casing part; at least one spring part connecting the body part and the gasket part,
wherein the body part is moveable in an airflow direction relative to the gasket part by bending or stretching the at least one spring part,
wherein in an unbiased basic condition of the gasket device the body part is positioned above a gasket plane defined by the gasket chamber.

The gasket device is made as a single part of a flexible, elastic material.

A drive circuit for operating a solenoid includes a main switch and a charge pump circuit. The main switch is coupled in series with a coil of the solenoid. The main switch is configured to selectively enable current flow from a voltage source according to a main switching signal to translate a poppet of the solenoid between an opened position and a closed position. The charge pump circuit is coupled to the voltage source. The charge pump circuit is configured to discharge through the coil to translate the poppet from the closed position to the opened position, and to charge when the poppet is held in the opened position.

A servo valve comprises a first spool extending along a first spool axis, a second spool extending along a second spool axis, a first piezoelectric actuator, and a second piezoelectric actuator. The first piezoelectric actuator is operatively connected to the first spool for translating the first spool in response to a voltage applied thereto. The second piezoelectric actuator is operatively connected to the second spool for translating the second spool in response to a voltage applied thereto.

A pump control assembly for controlling a variable displacement hydraulic pump includes a spool mounted within a valve block. The spool is configured to move between a first and a second position within the valve block so as to selectively control the displacement of the attached pump. The pump control assembly further includes first and second chambers that each apply a force to opposite ends of the spool. The first chamber is positioned at a first end of the spool in fluid communication with a pump output port. The second chamber is positioned at a second end of the spool and in fluid communication with a hydraulic tank port and a proportional pressure reducing valve. The second chamber also includes a piston and first and second springs positioned on either side of the piston. The proportional pressure reducing valve provides a regulated pressure to a first side of the piston along with the first spring, and the hydraulic tank port provides a tank pressure on the opposite side of the piston along with the second spring. The pump control assembly also includes a stop structure having a positive stop that limits movement of the piston in a direction toward the first chamber.

A pump control assembly for controlling a variable displacement hydraulic pump includes a spool mounted within a valve block. The spool is configured to move between a first and a second position within the valve block so as to selectively control the displacement of the attached pump. The pump control assembly further includes first and second chambers that each apply a force to opposite ends of the spool. The first chamber is positioned at a first end of the spool in fluid communication with a pump output port. The second chamber is positioned at a second end of the spool and in fluid communication with a hydraulic tank port and a proportional pressure reducing valve. The second chamber also includes a piston and first and second springs positioned on either side of the piston. The proportional pressure reducing valve provides a regulated pressure to a first side of the piston along with the first spring, and the hydraulic tank port provides a tank pressure on the opposite side of the piston along with the second spring. The pump control assembly also includes a stop structure having a positive stop that limits movement of the piston in a direction toward the first chamber.

A positioner drive for controlling a valve positioner with pneumatic output is configured to be mechanically coupled to a valve of the valve positioner with pneumatic output for controlling the valve positioner with pneumatic output.

A magnetic force compensator for at least partially compensating a closing force required to shift a valve of a pneumatic positioner into a closed position using a magnetic device, the magnetic device including a permanent magnet; and a magnetic counterpart; wherein the magnetic device and the magnetic counterpart are configured to interact to create an attracting force for the at least partially compensation of the closing force; and wherein the magnetic force compensator is configured to be mechanically coupled to the valve of the pneumatic positioner.

A magnetic force compensator for at least partially compensating a closing force required to shift a valve of a pneumatic positioner into a closed position using a magnetic device, the magnetic device including a permanent magnet; and a magnetic counterpart; wherein the magnetic device and the magnetic counterpart are configured to interact to create an attracting force for the at least partially compensation of the closing force; and wherein the magnetic force compensator is configured to be mechanically coupled to the valve of the pneumatic positioner.