subvolume 52 so that the fluid is as it were guided in the circuit via the return flow line 78 without losing fluid since the opening 84 is situated higher than the point at which the return flow line 78 discharges into the collecting tank 82 the fluid cannot emerge out of the opening 84 in the case of negative acceleration i e braking of the vehicle the fluid in the first subvolume 52 could rise if in the event of very severe deceleration the fluid rises to a sufficient extent that the collection container 82 is filled the fluid is if appropriate guided via the return flow line 78 into the rear subvolume 56 in which case the fluid will not emerge out of the opening 84 since this opening is situated higher than the point at which the return flow line 78 discharges into the collecting tank 82 an equalizing tank is therefore provided which does not have any pressure release valves or suction release valves and which can nevertheless equalize an excessive pressure or negative pressure and any changes in volume which may arise for example from changes in the temperature of the fluid or due to any freezing of the fluid the foregoing description of a preferred embodiment of the invention has been presented for purposes of illustration and description it is not intended to be exhaustive or to limit the invention to the precise form disclosed and modifications and variations are possible in light of the above teachings.