초록 ▼

The invention relates to a pressurized fluid mechanism comprising a plurality of pistons (14) and a plurality of different cylinder capacities. A particular cylinder capacity is selected by means of two identical slide valves (17, 18) which serve selectively to neutralize either a first overall cyli

The invention relates to a pressurized fluid mechanism comprising a plurality of pistons (14) and a plurality of different cylinder capacities. A particular cylinder capacity is selected by means of two identical slide valves (17, 18) which serve selectively to neutralize either a first overall cylinder capacity (45a) or a second overall cylinder capacity (45c), or both or neither of said first and second cylinder capacities. One application of the invention is to providing an efficient and compact motor which is cheap to produce.

대표청구항 ▼

A pressurized fluid (motor or pump) mechanism, e.g. a hydraulic motor having at least two selectable distinct non-zero cylinder capacities, the mechanisms being constituted by: at least one first external connector for connection to a source of fluid under pressure, and at least one second external

A pressurized fluid (motor or pump) mechanism, e.g. a hydraulic motor having at least two selectable distinct non-zero cylinder capacities, the mechanisms being constituted by: at least one first external connector for connection to a source of fluid under pressure, and at least one second external connector for connection to a fluid exhaust; at least one cam whose profile corresponds to a plurality of successive undulations, said undulations being divided at least into first and second distinct groups of undulations with each undulation comprising a first slope and a second slope; a cylinder block mounted to rotate relative to said cam about an axis of rotation and which includes a plurality of cylinders disposed substantially radially relative to said axis of rotation; each cylinder having at least one piston slidably mounted therein and suitable for bearing against the cam and delimiting, within said cylinder, a working chamber which is connected to a communication face of the cylinder block; a plurality of cylinder ducts each connecting one of the working chambers to said communication face of the cylinder block; a fluid distribution face constrained to rotate with the cam, said face permanently bearing against the communication face of the cylinder block and having first and second fluid distribution ducts opening out therein and corresponding to said first and second slopes of each of the undulations, said distribution ducts being suitable for being put into communication, during relative rotation of the cylinder block and the cam, with the cylinder ducts of the various cylinders; a first cylinder-capacity selection slide valve disposed between said first and second external connectors and the first and/or second distribution ducts corresponding to the undulations of the second group of undulations; a second cylinder-capacity selection slide valve disposed between said first and second external connectors and the first and/or second distribution ducts corresponding to the undulations of the first group of undulations; each of said first and second cylinder-capacity selection slide valves having two particular positions, which together correspond: (A) with the first cylinder-capacity selection slide valve and the second cylinder-capacity selection slide valve both being in their respective first positions, (a) to the first distribution ducts corresponding to the undulations of both groups of undulations being put into communication with the first external connector, and (b) to the second distribution ducts corresponding to the undulations in both groups of undulations being put into communication with the second external connector; (B) with the first cylinder-capacity selection slide valve being in its second position and the first cylinder-capacity selection slide valve being in its first position, (a) to the first distribution ducts corresponding to the undulations of the first group of undulations being put into communication with the first external connector, (b) to the second distribution ducts corresponding to the undulations of said first group of undulations being put into communication with the second external connector, and (c) to the first distribution ducts corresponding to the undulations of the second group of undulations being permanently isolated from the first external connector and/or to the second distribution ducts corresponding to the undulations of said second group of undulations being permanently isolated from the second external connector; (C) with the first cylinder-capacity selection slide valve in its first position and the second cylinder-capacity selection slide valve being in its second position, (a) to the first distribution ducts corresponding to the undulations of the second group of undulations being put into communication with the first external connector, (b) to the second distribution ducts corresponding to the undulations of the second group of undulations being put into communication with the second external connector, and (c) to the first distribution ducts corresponding to the undulations of the first group of undulations being permanently isolated from the first external connector and/or to the second distribution ducts corresponding to undulations of the first group of undulations being permanently isolated from the second external connector; and (D) with the first cylinder-capacity selection slide valve in its second position and the second cylinder-capacity selection slide valve in its second position, to the first distribution ducts corresponding to undulations of the first group of undulations being permanently isolated from the first external connector and to the second distribution ducts corresponding to the undulations of the second group of undulations being permanently isolated from the second external connector and/or to the second distribution ducts corresponding to the undulations of the first group of undulations being permanently isolated from the second external connector and to the first distribution ducts corresponding to the undulations to the second group of undulations being permanently isolated from the first external connector, and/or to the first distribution ducts corresponding to the undulations of both groups of undulations being permanently isolated from the first external connector, and/or to the second distribution ducts corresponding to the undulations of both groups of undulations being permanently isolated from the second external connector.