Abstract: A solar air and water heater comprises a solar energy collector which is crossed by a forced air flow fed by an electrically driven fan. The solar energy collector has an air inlet pipe and an air outlet pipe both connected to an air flow control device which is supported by the covering lid of a container which is filled with water. The air inlet pipe and the air outlet pipe of the solar energy collector can be connected, by means of the air flow control device, either to heat exchange means disposed within the container, so as to permit to heat the water inside the container by means of the hot air coming from the solar energy collector, or to an external circuit for direct utilization of this hot air, or to the heat exchange means and to the external circuit simultaneously, so as to permit both direct and indirect utilization of this hot air.

Abstract: A hydraulic servo-assisted braking system for motor vehicles has a master cylinder controlling two independent braking circuits through respective auxiliary cylinders each having an auxiliary piston with a central bore and an associated servo-piston with a stem which closes the said bore upon displacement of the servo-piston by hydraulic fluid pressure of source circuit, separable from the master cylinder, applied to the servo-piston through a common interception valve which is opened to admit the source pressure to the servo-pistons upon movement of either or both of a pair of pistons in a modulator cylinder subjected to the respective hydraulic pressures in the two brake actuator circuits. Failure of one of the braking circuits allows the other to remain operative, while damage to the servo-cylinders allows braking to remain effective through the master cylinder.

Abstract: A hydraulic actuator for a motor vehicle anti-skid braking system, in which the static and dynamic parts of the hydraulic circuit are separated, the actuator having a solenoid valve operated by electrical signals generated by sensors when associated wheels of the vehicle reach an incipient skid state; upon operation of the solenoid valve during braking, pressure to one side of a balanced piston is removed so that it moves to close a valve which cuts off braking pressure to the brakes. A throttle passage allows pressure build up to take place until equilibrium is established across said balanced piston allowing braking to recommence after a time delay.

Abstract: A hydraulic system for feeding a plurality of independent hydraulic servo-operated devices, such as servo-assisted brakes, clutch and/or servo-operated steering, in which a single pump draws fluid from a common reservoir and fluid pressure is automatically distributed by one or more modulating valves to the or each of the devices requiring power at any one time. The or each modulating valve comprises at least one piston in a cylinder, the piston being displaced by an increase in pressure due to displacement of one or more operating member such as brake or clutch pedal, or steering wheel, this controlling the flow of fluid through an axial passage in the piston by controlling its proximity to a valve shutter element and thereby controlling the fluid pressure in a chamber of the modulating valve, which pressure is fed to a control chamber of at least one distributor associated with a servo actuator of one of the servo operated devices of the system whereby to control the operating pressure applied to this.

Abstract: A servo-assisted hydrodynamic braking system of the type in which brake pedal pressure is used to control a modulating valve which restricts an output line of a pump thereby increasing the pressure in the output line which is connected to the master cylinder of the braking system in such a way as to apply this increased pressure as a servo-assisting pressure, in which the master cylinder and modulating valve are made as a composite assembly and the pressure within the master cylinder part is used to control the modulating valve so that no direct mechanical interconnection between the brake pedal and the modulating valve is needed.

Abstract: A power assisted hydraulic steering device in which the hydraulic actuators and the control valves are all contained in a common cylindrical housing surrounding a control shaft connectable to the steerable wheels of the vehicle, the actuator comprises an annular piston formed on the control shaft and housed in a cylinder defined between the control shaft and the sleeve. A control rod linked to the steering column is housed within the control shaft, which is hollow, and carries a valve element which cooperates with interior parts of the hollow control shaft to control fluid pressure applied to one side of the annular piston to cause displacement in one direction, or both sides of the annular piston, which has different areas on opposite sides, to cause displacement in the opposite direction.

Abstract: A fluid operated braking system for a motor vehicle, having a main braking circuit for applying braking pressure to the actuators of both wheels of at least one axle of the vehicle and a subsidiary braking circuit for applying a reduced braking pressure to one of the wheels of the axle if it should enter a skid or incipient skid state, in which the subsidiary braking circuit is controlled by two distributors each of which has three ports, one connected to the main braking circuit, one connected to the subsidiary braking circuit, and one connected to the brake actuator of an associated wheel of the axle, the distributor being controlled by an electrovalve to connect the main braking pressure circuit to the brake actuator of the associated wheel of the axle under normal condition and to connect the subsidiary braking circuit, through an internal path within the distributor to the brake actuator of one wheel of the axle when this wheel enters a skid or incipient skid state, without affecting the distributor asso

Abstract: A hydro-dynamic brake system of the type having a volumetric pump circulating brake fluid to a reservoir, and a modulating valve in the output of the pump acting under the control of the brake pedal to constrict the pipeline thereby increasing the pressure at the output of the pump. This pressure is fed to a distributor controlled by a solenoid valve and also receiving an input directly from a master cylinder which is also controlled by the brake pedal. Each wheel has a speed sensor feeding a processing and control circuit which produces an output signal to a solenoid valve which controls various transfer ports of the distributor. The distributor has a series of cylindrical cavities housing pistons which control valves in passages linking the chambers into which each cavity is separated by its piston.

Abstract: A master cylinder for a dual hydraulic braking system has two pistons arranged end-to-end in respective bore sections, each piston having sealing valves which close off communication between front and rear brake circuits and respective reservoirs when displaced by operation of a brake pedal to cause pressurization of respective compression chambers connected to the brake circuits. This invention provides two seals in the inner piston between the two compression chambers and an auxiliary chamber defined between these seals into which small quantities of brake fluid escape in the event of leakage from either compression chamber to give visual warning of such leakage.