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 self-contained hydraulic lash adjuster having a cup-shaped body and a plunger slidably disposed therein is further provided with a flexible diaphragm secured within a reservoir chamber located in the plunger with one side of said diaphragm being exposed to the atmosphere and the other side being disposed in engagement with the oil supply sealed within the hydraulic lash adjuster. An oil passage is provided in the bottom of the plunger to communicate the reservoir chamber with a pressure chamber defined between the bottom of the plunger and the bottom of the body and a one-way check valve is provided to prevent the return flow of oil through the oil passage to the reservoir. A cup-shaped cover member having apertured side walls is located in the bottom of the plunger over the oil passage to prevent the diaphragm from blocking the oil passage upon deformation of the diaphragm.

Abstract: An oil-containing hydraulic lifter for lash adjustment comprising relatively movable cylinder and plunger members defining a pressure chamber between their closed ends and a reservoir chamber within the plunger. Means are provided for rapid, one-way flow of the oil from the reservoir to the pressure chamber during outward movement of the plunger and for slow, one-way flow from the pressure to the reservoir chamber during inward movement of the plunger. A flexible, bag-shaped diaphragm extending into the reservoir chamber has its open, upper end sealed liquid tightly to the inner wall of the reservoir for sealing in the oil while expanding and collapsing with reciprocation of the plunger. The reservoir chamber has an increased diameter at that part where the diaphragm undergoes most of its expansion and collapse, thereby spacing the inner wall of the reservoir chamber from the diaphragm by a distance great enough to allow full expansion of the diaphragm in the expanding and collapsing operation thereof.