Electronic level regulators for fluid-type suspensions of motor vehicles and the like

Claim 1

In an electronic regulating device for fluid-type suspensions for motor vehicles and the like, whose level is maintained substantially constant by the regulating device through the medium of a movable arm, of a regulating switch, actuated in accordance with the distance between the vehicle body and the vehicle axle, the switch being connected to a grounded source of DC potential and the arm having an ''''up'''' regulating range providing the control signal ''''feed fluid,'''' a neutral control range and a ''''down'''' regulating range providing the control signal ''''drain fluid'''', the control signals initiating, with a time delay provided by condensers and associated charging resistances, the actuation of control amplifiers which connect one or the other known means, executing the respective control signals, with the potential source: the improvement comprising, in combination, a condenser having one terminal connected to the grounded terminal of said source; said switch including an ''''up'''' regulating contact surface which is grounded, a ''''down'''' regulating contact surface connected to the ungrounded terminal of said source, and a ''''neutral'''' control range between said ''''up'''' and ''''down'''' contact surfaces; charging resistance means connecting the other terminal of said condenser to said switch arm; and first and second control amplifiers connected to said condenser, one operable to initiate feeding of fluid and the other operable to initiate draining of fluid; one control amplifier being activated by condenser voltages below a lower limiting voltage close to ground potential of said source, and the other control amplifier being activated by condenser voltages above an upper limiting voltage close to the ungrounded potential of said source; both control amplifiers being deactivated at condenser voltages between said upper and lower limiting voltages.