초록 ▼

A swashplate assist mechanism for dynamically varying swashplate moments in a multiple piston hydraulic unit includes a valve means disposed in the swashplate and defining a variable orifice for metering fluid from at least one of the pistons; and means for generating a control error signal to the v

A swashplate assist mechanism for dynamically varying swashplate moments in a multiple piston hydraulic unit includes a valve means disposed in the swashplate and defining a variable orifice for metering fluid from at least one of the pistons; and means for generating a control error signal to the valve means so as to adjust the size of the variable orifice based upon the control error signal. When fluid is metered from a leading piston to a trailing piston near one or more of the pressure transition zones, or when fluid is metered from a trailing piston to a leading piston near the opposite transition zones, the swashplate moments can be reduced.

대표청구항 ▼

1. A swashplate position assist mechanism for a hydrostatic unit including a swashplate assembly tiltable about a tilt axis and having a slipper running surface thereon, a rotatable cylinder block assembly with a plurality of piston bores therein, and a corresponding plurality of piston assemblies e

1. A swashplate position assist mechanism for a hydrostatic unit including a swashplate assembly tiltable about a tilt axis and having a slipper running surface thereon, a rotatable cylinder block assembly with a plurality of piston bores therein, and a corresponding plurality of piston assemblies each including a slipper attached to a piston that axially reciprocates in one of the plurality of piston bores, a fluid passage extending through the piston assembly to the slipper running surface, the mechanism comprising:a valve disposed in the swashplate assembly and defining a variable orifice for metering fluid from the fluid passage of at least one of the pistons; and means for generating a control error signal to the valve so as to adjust the size of the variable orifice based upon the control error signal.