Electrically controlled throttle valve
AssigneeHusqvarna AB
InventorMartin LINDEKULL
Life of this patent
Estimating the term…
Abstract
A throttle valve arrangement for a handheld power tool, the throttle valve arrangement comprising a valve plate attached to a valve shaft, the valve shaft being arranged to rotate about a valve shaft axis from an idle throttle position to a wide open throttle, WOT, position, wherein the rotation of the valve shaft about the valve shaft axis is arranged to be biased towards a configurable valve shaft angle by a first actuator, wherein a second actuator of the throttle arrangement is arranged to resist rotation of the valve shaft about the valve shaft axis towards the WOT position, past an angle determined by a state of the second actuator.
Claims17
A throttle valve arrangement for a handheld power tool,
- the throttle valve arrangement comprising a valve plate attached to a valve shaft, the valve shaft being arranged to rotate about a valve shaft axis from an idle throttle position to a wide open throttle (WOT) position,
- wherein the rotation of the valve shaft about the valve shaft axis is arranged to be biased towards a configurable valve shaft angle by a first actuator,
- wherein a second actuator of the throttle arrangement is arranged to resist rotation of the valve shaft about the valve shaft axis towards the WOT position, past an angle determined by a state of the second actuator.
A method for controlling a throttle valve arrangement of a handheld power tool, the throttle valve arrangement comprising a valve plate attached to a valve shaft, as well as a first actuator and a second actuator arranged to engage the valve shaft and jointly control the state of the valve plate, the method comprising
- configuring the first actuator to limit a throttle span of the throttle valve arrangement to an upper limit between idle and wide open throttle (WOT),
- configuring the second actuator to govern a state of the valve plate over the throttle span,
- obtaining, by a control unit of the handheld power tool, data related to an engine speed of the handheld power tool, and
- reducing the upper limit of the throttle span, by the first actuator, in response to the engine speed exceeding a desired maximum engine speed.
A handheld power tool comprising an active part driven by a two-stroke combustion engine,
- the two-stroke combustion engine comprising a throttle valve arrangement arranged to regulate an air intake of the engine by control of a state of a valve plate attached to a valve shaft,
- the throttle valve arrangement comprising a first actuator, and a second actuator arranged to jointly engage the valve shaft and to jointly control the state of the valve plate,
- wherein the first actuator comprises an automated electrically operated actuator and the second actuator comprises a manually operated actuator.
Dependencies are inferred from the claim text.