Valve timing in electronically commutated hydraulic machine
AssigneeArtemis Intelligent Power Limited
InventorsNiall Caldwell, Daniel Abrahams, Andrew Latham
Life of this patent
Estimating the term…
Abstract
An electronically commutated hydraulic machine is coupled to a drivetrain. Working chambers of the hydraulic machine are connected to low and high pressure manifold through electronically controlled valves. The phase of opening and closing of the valves has a default. In order to avoid cycle failure due to acceleration events, for example due to backlash in the drivetrain, the phase of opening or closing of the electronically controlled valves is temporarily advanced or retarded from the default timing.
Claims26
Apparatus comprising a fluid working machine, the fluid working machine comprising a rotatable shaft, at least one working chamber having a volume which varies cyclically with rotation of the rotatable shaft, a low pressure manifold and a high pressure manifold, a low pressure valve for regulating communication between the low pressure manifold and the working chamber, a high pressure valve for regulating communication between the high pressure manifold and the working chamber, a controller configured to actively control one or more said valves in phased relationships with cycles of working chamber volume, to determine the net displacement of fluid by the working chamber on a cycle by cycle basis, wherein for a given cycle type, the controller is configured to by default transmit control signals to the low or high pressure valves at a default phase angle of a cycle of working chamber volume, the control signals causing the opening or closing of the low or high pressure valves and, responsive to an event associated with a temporary change in the pressure in the high pressure manifold, to transmit the control signals at an alternative phase angle of cycles of working chamber volume, which alternative phase angle is advanced or retarded relative to the default phase angle.
Apparatus comprising a fluid working machine, the fluid working machine comprising a rotatable shaft, at least one working chamber having a volume which varies cyclically with rotation of the rotatable shaft, a low pressure manifold and a high pressure manifold, a low pressure valve for regulating communication between the low pressure manifold and the working chamber, a high pressure valve for regulating communication between the high pressure manifold and the working chamber, a controller configured to actively control one or more said valves in phased relationships with cycles of working chamber volume, to determine the net displacement of fluid by the working chamber on a cycle by cycle basis, wherein for a given cycle type, the controller is configured to by default transmit control signals to the low or high pressure valves at a default phase angle of a cycle of working chamber volume, the control signals causing the opening or closing of the low or high pressure valves and, responsive to a measurement of an event associated with a temporary acceleration of the rotatable shaft, to transmit the control signals at an alternative phase angle of cycles of working chamber volume, which alternative phase angle is advanced or retarded relative to the default phase angle.
Apparatus comprising a fluid working machine, the fluid working machine comprising a rotatable shaft, at least one working chamber having a volume which varies cyclically with rotation of the rotatable shaft, a low pressure manifold and a high pressure manifold, a low pressure valve for regulating communication between the low pressure manifold and the working chamber, a high pressure valve for regulating communication between the high pressure manifold and the working chamber, a controller configured to actively control one or more said valves in phased relationships with cycles of working chamber volume, to determine the net displacement of fluid by the working chamber on a cycle by cycle basis, wherein for a given cycle type, the controller is configured to by default transmit control signals to the low or high pressure valves at a default phase angle of a cycle of working chamber volume, the control signals causing the opening or closing of the low or high pressure valves and, responsive to an algorithmic prediction of an event associated with a temporary acceleration of the rotatable shaft, to transmit the control signals at an alternative phase angle of cycles of working chamber volume, which alternative phase angle is advanced or retarded relative to the default phase angle.
Dependencies are inferred from the claim text.