Hydraulic Control Unit for Precise Operation of Manual Systems

Complex hydraulic systems that are designed to perform multiple functions require a control unit.

In highly complex systems, hydraulic control is performed via electromechanically actuated valves. For manual systems, however, the hydraulic control unit has become established. It combines the advantages of low cost, high reliability, and power-free operation.

How Hydraulic Control Units Work

The hydraulic control unit is located between the pump and the actuator. It directs the incoming pressure to the various valves, linear, or radial motors. The more complex the control is designed, the greater the number of connections required on the hydraulic control unit.

Pressure distribution is achieved via integrated control valves. These are operated with an externally mounted lever. Normally in the rest position, the lever springs back to the center by itself. In doing so, it blocks the volume flow, and the actuator performs no movement. Moving the lever to the right, left, and possibly up and down, triggers different functions.

Typical Applications of Hydraulic Control Units

Hydraulic control units are used wherever volume flows need to be redirected quickly. A simple hydraulic jack, therefore, does not require such support. These systems only need a changeover valve that allows the hydraulic oil to flow back into the tank.

However, where multiple actuators need to be activated and deactivated in quick and arbitrary succession, a hydraulic control unit is indispensable. Typical application areas for these components can be found in the following systems:

• Agricultural vehicles
• Construction machinery
• Log splitters
• Heavy military equipment
• Complex, stationary hydraulic systems

In agricultural vehicles and equipment, the hydraulic control unit is used to operate lifting gears, pressure cylinders, or radial motors. Attached excavator buckets on tractors can also be comfortably operated with it. In construction machinery, these components are the central control element. They are used in excavators, telehandlers, crawlers, and wheel loaders. Log splitters become particularly fast and efficient through the use of a control unit. The use of a control unit also makes the machines movable even if the electronics fail. The device can at least be brought into a safe idle state.