公开(公告)号：US20230336105A1

公开(公告)日：2023-10-19

申请号：US18134309

申请日：2023-04-13

Applicant: MAKITA CORPORATION

Inventor： Dai SUZUKI ,  Masayuki OKAMURA ,  Itsuku KATO

IPC: H02P29/032 ,  B25F5/00 ,  H02P6/24

CPC classification number: H02P29/032 ,  B25F5/00 ,  H02P6/24

Abstract: An electric working machine in one aspect of the present disclosure calculates an estimated heat value based on an electric current value and a parameter. The estimated heat value corresponds to an estimated heat generation amount of a motor. The electric current value corresponds to a magnitude of an electric current delivered from a power source to the motor. The electric work machine varies the parameter based on a load time. The load time corresponds to a time period during which a first load is continuously imposed on the motor. The first load has a specified magnitude or more. The electric work machine performs a protective operation for over temperature protection of the motor based on the estimated heat value having reached a heat threshold.

公开(公告)号：US20240364097A1

公开(公告)日：2024-10-31

申请号：US18637892

申请日：2024-04-17

Applicant: MAKITA CORPORATION

Inventor： Kazuaki USAMI ,  Masayuki OKAMURA ,  Dai SUZUKI ,  Kouichi TAKEDA

IPC: H02H7/085 ,  A01G3/08 ,  B27B17/02 ,  B27B17/08

CPC classification number: H02H7/085 ,  B27B17/08 ,  A01G3/086 ,  B27B17/02

Abstract: An electric work machine according to the present disclosure includes: a motor; and a first control circuit. The first control circuit increases a first counter on the basis of the acquired or estimated line current value being greater than a current threshold. The first control circuit decreases the first counter on the basis of the calculated rotational speed being greater than a speed threshold. The first control circuit stops the motor on the basis of the first counter exceeding a first threshold.