Hydraulic transmission apparatus making quick positive clutching/declutching possible

摘要

Hydraulic transmission apparatus including a pressurized fluid source and at least one hydraulic motor fed by said pressurized fluid source. The motor has two motor ducts for feed/discharge, and one casing duct. The motor can be operated in assisted mode, in which it generates torque or in unassisted mode in which it does not generate any torque and its pistons are maintained in the retracted position under the effect of the pressure in the casing duct. The apparatus further includes an accumulator suitable for feeding:
the motor ducts during a stage of passing from the unassisted mode to the assisted mode in order to facilitate deployment of the pistons; andthe casing duct during a stage of passing from the assisted mode to the unassisted mode in order to facilitate retraction of the pistons.;This apparatus thus enables the motor to be positively clutched/declutched quickly.

主权项

1. Hydraulic transmission apparatus for a vehicle, the apparatus including a pressurized fluid source and at least one hydraulic motor suitable for being fed with hydraulic fluid by the pressurized fluid source in order to drive at least one vehicle mover member;
the motor being connected to: a motor duct for feeding said motor with fluid, and a motor duct for discharging fluid from said motor, which motor ducts are suitable for being put into communication with cylinders arranged in a cylinder block and including pistons suitable for sliding in said cylinders; and a casing duct connected to an internal space arranged inside a casing containing the cylinder block; the motor being suitable for being operated in assisted mode, in which it generates drive torque or braking torque under the effect of a pressure difference between the motor ducts, and in freewheel mode or unassisted mode in which the motor does not generate any torque and the pistons are maintained in the retracted position inside the cylinders; the apparatus further including an accumulator suitable for feeding both of the motor ducts during a stage of passing from the unassisted mode to the assisted mode in order to facilitate deployment of the pistons; wherein the accumulator is also suitable for feeding the casing duct so as to put said duct under pressure during a stage of passing from the assisted mode to the unassisted mode in order to facilitate retraction of the pistons.