US 12,336,454 B2 · Self propelled mower with safety device

Abstract

An autonomous self-propelled mowing vehicle includes a frame fitted with a drive mechanism, a mowing device for mowing plants, a bumper device, and a control unit. The bumper device includes a first and a second impact detector. The first impact detector is depressible up to a stop and is provided with a first switch which emits a first signal to the control unit at a first switching point, if the first impact detector is depressed beyond the switching point. The second impact detector is deformable and locally depressible, and is provided with a second switch which emits a second signal to the control unit if the second impact detector is depressed at least beyond a predetermined depression threshold. The control unit is configured to stop the drive mechanism upon receiving the second signal, and to regulate the drive mechanism in such a way that the speed of the mowing vehicle is reduced to a lower mowing speed upon receiving the first signal without receiving the second signal. This prevents plants to be mowed from pushing the bumper away across the bumper width beyond the switching point of the first impact detector, without losing its long depressibility, because the second impact detector, which itself has a much smaller depressibility, detects obstacles at the lower (mowing) speed by being depressed itself.

Claims19

Dependent claims

An autonomous self-propelled mowing vehicle, comprising a frame fitted with:

a drive mechanism for driving the mowing vehicle in a direction of travel at a speed of travel during driving;
a mowing device for mowing plants situated on the land;
a bumper device;
a control unit for the mowing vehicle which is operatively connected to the bumper device;
a gathering device;
and
a holder for accommodating mowed plants,
wherein the bumper device comprises:
a first impact detector;
and
a second impact detector,
wherein the first impact detector is depressible as a whole along a path with respect to the frame up to a stop on account of a force acting thereon, and is provided with a first switch which is connected to the control unit and is configured to emit a signal to the control unit in response to the impact detector being pushed in beyond a first switching point,
wherein the second impact detector is deformable and locally depressible beyond a depressibility on account of a force acting thereon, and is provided with a second switch which is connected to the control unit and which emits a second signal to the control unit in response to the second impact detector being depressed at least beyond a predetermined depression threshold, and
wherein the control unit is configured:
to stop the drive mechanism upon receiving the second signal;
and
to regulate the drive mechanism in such a way that the speed is reduced to a lower speed of travel upon receiving the first signal without receiving the second signal.

14 more elements

An autonomous self-propelled mowing vehicle, comprising a frame fitted with:

a drive mechanism for driving the mowing vehicle in a direction of travel at a speed of travel during driving;
a mowing device for mowing plants situated on the land;
a bumper device;
and
a control unit for the mowing vehicle which is operatively connected to the bumper device,
wherein the bumper device comprises:
a first impact detector;
and
a second impact detector,
wherein the first impact detector is depressible as a whole along a path with respect to the frame up to a stop on account of a force acting thereon, and is provided with a first switch which is connected to the control unit and is configured to emit a signal to the control unit in response to the impact detector being pushed in beyond a first switching point,
wherein the second impact detector is deformable and locally depressible beyond a depressibility on account of a force acting thereon, and is provided with a second switch which is connected to the control unit and which emits a second signal to the control unit in response to the second impact detector being depressed at least beyond a predetermined depression threshold, and
wherein the control unit is configured:
to stop the drive mechanism upon receiving the second signal;
and
to regulate the drive mechanism in such a way that the speed is reduced to a lower speed of travel upon receiving the first signal without receiving the second signal,
wherein the speed of travel is chosen in such a way that a braking distance of the mowing vehicle after receiving the second signal at this speed of travel is at most equal to a horizontal distance between the first switching point and said stop, and
wherein the autonomous self-propelled mowing vehicle further comprises a suspension feature, the suspension feature being a spring device or hydraulic or pneumatic cylinder connected to the frame and to at least one of the first impact detector and to the second impact detector.

14 more elements

Dependencies are inferred from the claim text.

Self propelled mower with safety device

Life of this patent

Self propelled mower with safety device

Life of this patent

Abstract

Claims19