Patent EP-0192899-A1 (EP)
Inventor: LAGUIONIE PIERRE
IPC: F15B13/042
Filed: 1985-01-28
Abstract: 1. Pressurized fluid supply circuit supplying at least one consuming part (10, 11), constituted by; - said at least one consuming part (10, 11), - at least one variable displacement pump (1), - a device (16-21) for adjusting the volume of said variable displacement pump, - as many main distributors (12, 13) of pressurized fluid as there are consuming parts, each main distributor (12, 13) being operationally coupled (41-43, 45-47) with one of said consuming parts (10, 11) and being interposed between said consuming part and the delivery pipe (19) with which said variable displacement pump is equipped, - a source of control fluid (38) for controlling each main distributor, and, - as many hydraulic manipulators (14, 15) as there are main distributors (12, 13), each manipulator being associated to one of the main distributors and being interposed between said main distributor (12, 13) and the source of control fluid (38), the source of control fluid comprising a pump (3) provided with a delivery pipe (68) on which is provided a calibrated discharge valve (69), characterized in that the pump (3) of the source of control fluid is part of a tachometric device which delivers a control pressure of which the value is a function of the driving speed of the variable displacement pump (1), whereas the hydraulic manipulators (14, 15) of the main distributors (12, 13) are of a potentiometric type, each one comprising first (35) and second (36) internal pipes, on each one of which are placed two variable constrictions (48, 49; 50, 51) of adjustable value, said two internal pipes being connected, upstream from said two constrictions, with the source of control fluid (37, 38), and downstream from said two constrictions, with a discharge of pressurized fluid (39) and in that, on the one hand, each main distributor (12, 13) being equipped with first (41, 45) and second (43, 47) opposingly operating control members, first and second control pipes are connected, the first control pipe (40, 44) to the first internal pipe (35) between the two constrictions (48, 49) provided on said first internal pipe, and the second control pipe (42, 46) to the second internal pipe (36), between the two constrictions (50, 51) provided on said second internal pipe, and to the second control member (43, 47), the single control (32) of manipulator (14, 15) being adapted to perform the progressive adjustement of the values of the constrictions provided on the first and second internal pipes, according to at least the three following configurations : a) when the single control member (32, Figure 1) is not actuated, the two upstream constrictions (48, 50) have their minimum opening and the two downstream constrictions (49, 51) have their maximum opening ; b) when the single control member is actuated in a first direction (Figure 3), the openings of the upstream constriction (48) of the first internal pipe (35) and of the downstream constriction (51) of the second internal pipe (36) are maximum, and, the openings of the downstream constriction (49) of the first internal pipe (35) and of the upstream constriction (50) of the second internal pipe (36) are minimum ; and c) when the single control member is actuated in a second direction (Figure 2), the openings of the upstream constriction (50) of the second internal pipe (36) and of the downstream constriction (49) of the first internal pipe (35) are maximum, and, the openings of the downstream constriction (51) of the second internal pipe (36) and of the upstream constriction (48) of the first internal pipe (35) are minimum.