Hydrostatic drive
AssigneeRobert Bosch GmbH
InventorHeinz-Gerhard Essig
Life of this patent
Estimating the term…
Abstract
A hydraulic additional drive includes a hydraulic or having working ports configured to be connected to a pump via a high pressure branch and a low pressure branch. The hydraulic motor further includes a purging port to which a feed pressure is configured to be applied to set a “free-wheel mode” while the working ports are connected to a tank. The pressure at the purging port is limited to a comparatively low value between the feed pressure and the tank pressure by a pre-charging valve integrated into the hydraulic motor. The pre-charging valve is arranged in a free-wheel duct which hydraulically connects the purging port to one of the working ports.
Claims15
A hydrostatic drive, comprising:
- at least one hydraulic motor including:
- a motor housing forming working connections configured to be connected via a high pressure branch and a low pressure branch to a pump, and
- pistons configured to be acted upon by a housing pressure and with low pressure or with pump pressure;
- a flushing connection disposed on a housing side and configured to be connected to a tank;
- a feed line configured to convey pressurizing medium to the low-pressure side;
- a valve arrangement via which tank pressure is configured to act at least on the two working connections and the feed pressure is configured to act on the flushing connection via a feed pressure line to set a freewheel mode;
- a freewheel passage formed in the motor housing, the passage connecting the flushing connection and one of the working passages connected to one of the working connections of the hydraulic motor;
- and
- a counterbalance valve which is arranged in the passage and which opens towards the working passage, the counterbalance valve opening in the case of a substantially lower pressure than the feed pressure.
Dependencies are inferred from the claim text.