Patent ID: 6553760
Filing Date: 2003-04-29
Classification: F04C,F16H

Abstract:
A control device for a hydrostatic transmission,said transmission including a motor pump, in communication with an impelling pump by means of a fluid circuit, said impelling pump comprising a rotor and a stator contained inside a body; the fluid debit of said impelling pump is infinitely variable, in accordance with the infinitely variable amplitude of the radial decentralization of said stator, obtained by means of the impulsion of a first and second rod; the variable work pressures of the fluid which act in each internal side of said stator are compensated and balanced on the corresponding external side, by equal fluid, thus resulting to be small and independent from the said work pressures of the fluid, the needed force applied in the impulsion of said first and second rods; said control devices of a hydrostatic transmission comprising: a first cylinder, which communicates with the side of the hydrostatic circuit by means of the hydrostatic extension; said first cylinder contains a first piston which actuates on said first rod in order to obtain the infinitely variable decentralization of said stator; a second cylinder communicating with a vacuum feeding circuit, by means of first and second ways; said first and second ways connected to a valve which commends the direction of actuation of the vacuum; said second cylinder contains a second piston fastened with said second rod, said second rod acting in order to obtain the variation of the direction of the circulation of the fluid in said transmission; and first, second and third spring systems, of laminar type, whose pressure control the reciprocating position of said first and second pistons and the reciprocating position of said first and second rods.