FR2620788A1 - Hydraulic valve for automatically regulating flow rates and pressures - Google Patents

Abstract

Hydraulic valve for continuous automatic regulation mainly intended for hybrid drives of vehicles (mechanical and hydraulic) and operation of various machines needing variation in speed and power. Significant advantage, this valve may be mounted with a constant flow-rate pump. This valve is composed of a unit in which there slides a distributing piston, a fluid inlet orifice, an orifice to tank, and a user orifice towards hydraulic motors or machines by means of an electric directional control device for reversing the direction of running if required. A controlled pressure limiting device makes this system safe. An assembly forming an adjustable limiting device makes it possible to regulate the user flow-rate. This limiting device includes an orifice closed by a shutter, in this case a ball pressed onto its seat by a guide and adjustable spring. This ball experiences the variation in pressure of the drive circuit via a piston of the same diameter as the ball seat by means of a spring which is very important because it prevents the piston from becoming jammed.

Description

Hydraulic valve for automatic flow and pressure regulation.

Mainly intended for mixed transmissions (mechanical-hydraulic) this valve instantly adjusts the flow and pressure of a constant flow pump at the request of the hydrsulic motors of the vehicle to be propelled. This system eliminates the risk of overheating and is also very economical for power. and consumption of heat engines. This synchronization allows the use of wheels of indifferent diameters.

This valve consists of a block (1) perceived from orifices (preseion inlet (2). Use outlet (5), outlet to tank (18,) pilot leakage outlets (8). In this bloo slides a distributor piston ( 3) comprising inlet (19) and fluid outlet (4j and (I7) lights, a pilot leak (I6), a piled compression chamber (9) with its spring (7).

This piston has an annular section forming a shock absorber and preventing jolts in the transmission. A piloted pressure relief valve 6) avoids any risk of overpressure.

be automatic regulation system is constituted by an orifice closed by a ball or valve, this ball is supported on the orifice of the seat by a spring (14) with guide and pre-setting screw (13) which can make the pressure prevail in the circuit piloting. A piston (11) of the diameter of the orifice closed by the ball bears by means of a spring (10) on the guide of the ball. Being in contact with the fluid of the engine oil at the other end of the piston (12) on the regulator block (15) - at the slightest stress the piston (11) ap.

draws or releases the ball. The spring (10) plays a very important role because it prevents the piston from stabilizing, thus blocking, and gives all the sensitivity and precision to the system.

As soon as the engines are running, the pressures balance 4years in the circuits and the piston (Tt) plays its regulating role on the required pressure and flow.

This valve can be used for the operation of various machines and can be controlled manually, electrically and mechanically

Claims (1)

 Claims -1- Hydraulic valve with automatic system of continuous regulation of flow and pressure intended mainly to be used for drive synchronized nixes of vehicles. Example: Mechanical Rear - Hydraulic scientist - or assistance of towed vehicles. This valve can be supplied by a constant flow pump much cheaper than variable flow pumps. -2- Device according to claim 1 characterized in that this automatic regulation system is constituted by a piston of the same diameter as the orifice closed by the calibration ball, with adjustable pre-taring spring and; very important an intermediate spring of sensitivity giving all the precision to the operation of this valve. -3- Device according to claim 1 characterized in that this valve has a distributor piston having an annular section forming a shock absorber avoiding jolts in the transmissions.