Abstract: A cooling fan for an internal combustion engine hydraulically driven by a flow of propellant hydraulic fluid is controlled of its rotational speed by a system which includes a device for sensing a value representing the operating temperature of the engine, a device for sensing the operating temperature of the propellant hydraulic fluid, and a device for controlling the flow of the propellant hydraulic fluid, so as to increase the flow rate of the propellant hydraulic fluid when the operating temperature of the engine increases and also when the operating temperature of the propellant hydraulic fluid increases.

Abstract: In an automotive vehicle wherein the cooling fan for the internal combustion engine is driven hydraulically by a flow of a first propellant hydraulic fluid, while the power steering device for the steering system is driven hydraulically by a flow of a second propellant hydraulic fluid, reservoirs for storing the first and second propellant hydraulic fluids are provided as first and second tank portions, respectively, of a common reservoir tank, so that the first propellant hydraulic fluid which is more apt to be heated up by friction loss is cooled down by the second propellant hydraulic fluid which remains at ambient temperature as effectively cooled through the power steering fluid circulation system.

Abstract: A coal - water slurry at high concentration which has a low viscosity and favorable flowing property is prepared by using a surface active substance prepared by sulfonating and oxidizing at least one of the starting materials selected from distilled petroleum oils, petroleum pitches, asphalts, distilled coal oils, coal pitches or coals, applying condensation as required and then neutralizing the thus obtained product with alkalis.

Abstract: A thermostat comprising a valve and a wax container connected to the valve. A drive rod projects from the end face of the wax container and is connected to the casing of the thermostat. The drive rod is actuated by the expanding operation of the wax contained in the wax container. A hollow cylindrical sealing sleeve is arranged on the end face of the wax container and has a hole through which the drive rod passes. A plurality of triangular shaped projections is formed on the inner wall of the hole of the sealing sleeve. A spring cap is fitted onto the sealing sleeve for pressing the triangular shaped projections onto the drive rod due to the spring force of the spring cap.

Abstract: A thermostat valve of the type actuated by a wax cylinder incorporating a needle piston, wherein the diameter of said needle is reduced at least at a portion thereof which is received in a bore of the wax cylinder.

Abstract: A device for controlling the flow of cooling water circulating between the radiator and the water jacket in an internal combustion engine. A thermal reactive valve means is disposed in a passage interconnecting the radiator and the water jacket for providing a first and a second opening for permitting the cooling water to flow therethrough, said first and second openings being opened at a predetermined first and second temperature of the cooling water, respectively.

Abstract: A cooling system for lubricating oil in an internal combustion engine is disclosed, said system comprising a pressure-regulating valve adapted for controlling the pressure in said system, said valve having a passageway means connecting it to an oil pump and other passageway means for diverting a part of said lubricating oil therethrough from said oil pump to an oil pan located at the bottom of said engine when the pressure in said system exceeds a predetermined value, said other passageway means extending to a position located adjacent to an upper portion of the inner surface of the front wall of the engine casing. Said other passageway means may be extended to a position facing the upwardly moving part of a timing chain which connects the crankshaft to the cam shaft.