Abstract: A regulating and controlling device for a fluid pressure booster installation includes a motor-driven pressure generating unit, a check valve, a relief valve and a pressure switch. The pressure switch has a first cylinder-piston arrangement for connecting the drive motor to a source of electrical energy. The first cylinder-piston arrangement includes a piston rod for contacting an intermediate member. The device has, as an improvement, a second cylinder-piston arrangement, a third cylinder-piston arrangement and a gear unit. The improvement prevents longer-lasting circulation delivery and, accordingly, an overheating of the working fluid. This also avoids any need for the pressure switch to be constructed so as to be adjustable in operation with respect to switch-off pressure or any need to be adjusted when changing the pressure value of the relief valve used for adjusting the pressure at the pressure outlet of the device.

Abstract: Pressure switch for moving an electrical contact arrangement including a switch frame supporting fixed contacts and movable contacts, the movable contacts being supported particularly on a contact carrier of the switch frame which is pivoted about a first axis. An intermediate rocking lever is guided on the switch frame and is pivoted about a second axis. A first spring arrangement biases the rocking lever upwardly, and a snap arrangement, containing a torsion coil spring, is interconnected between the rocking lever and the contact carrier. A transmission member, which is moved downwardly by a fluid pressure sensitive piston rod connected thereto, has rollers bearing upon the upper surface of the rocking lever and engages, after a certain downward movement thereof, with a second spring arrangement.