US 12,337,498 B2
Method for operating a hand-guided processing device, and hand-guided processing device
Alexander Haas, Spraitbach (DE); Edgar Mueller, Ebersbach an der Fils (DE); and Christian Nemec, Duernau (DE)
Assigned to Andreas Stihl AG & Co. KG, Waiblingen (DE)
Filed by Andreas Stihl AG & Co. KG, Waiblingen (DE)
Filed on Jan. 21, 2021, as Appl. No. 17/154,753.
Claims priority of application No. 20153081 (EP), filed on Jan. 22, 2020.
Prior Publication US 2021/0221022 A1, Jul. 22, 2021
Int. Cl. B27B 17/08 (2006.01); B25F 5/00 (2006.01); H02P 6/08 (2016.01); H02P 6/12 (2006.01); H02P 29/68 (2016.01)
CPC B27B 17/08 (2013.01) [B25F 5/001 (2013.01); H02P 6/08 (2013.01); H02P 6/12 (2013.01); H02P 29/68 (2016.02)] 15 Claims
OG exemplary drawing
 
1. A method for operation of a hand-guided processing device, wherein the processing device comprises:
a rotating or circulating cutting tool;
an electric motor drive system, wherein:
the electric motor drive system is configured for generating a torque for driving the cutting tool;
a monitoring and control device; and
a user-operable control element configured to be user-adjustable,
wherein the method comprises the steps of:
a) using the monitoring and control device to automatically monitor whether a blocking criterion is fulfilled, wherein:
the blocking criterion is characteristic of a processing piece to be cut by the cutting tool causing movement of the cutting tool to be at least one of blocked or seized;
b) in response to the blocking criterion being fulfilled and the control element being operated, using the monitoring and control device to automatically lower the torque generated by the electric motor drive system that drives the cutting tool while the blocking criterion is fulfilled, and subsequently, automatically increase the torque generated by the electric motor drive system that drives the cutting tool; and
c) in response to the blocking criterion not being fulfilled and the control element is operated, automatically controlling or regulating the torque generated by the electric motor drive system for reaching a nominal rotational speed of at least one of the electric motor drive system or the cutting tool, where the nominal rotational speed is based on a setting associated with the user-operable control element set by a user, wherein:
a non-blocking rotational speed lower limit value for the nominal rotational speed is at least twice as great as greater than a blocking rotational speed lower limit value;
wherein the processing device is at least one of a gardening, forestry, or construction processing device, and
wherein the blocking criterion is that while the control element is operated, the generated torque driving the cutting tool is greater than zero, and current effecting the torque is greater than zero, at least one of a rotational speed of the electric motor drive system is less than or equal to the blocking rotational speed lower limit value or a rotational speed of the cutting tool is less than or equal to the blocking rotational speed lower limit value.