Patent classifications
B27B17/08
ELECTRIC WORK MACHINE
An electric work machine reduces a decrease in the detection accuracy of rotation of a rotor while avoiding generation of insufficient reluctance torque. The electric work machine includes a brushless motor including a rotor and a stator, and a magnetic sensor. The rotor includes a rotor core and permanent magnets. The magnetic sensor faces a first end of the rotor core to detect rotation of the rotor. The rotor core includes a first core including the first end and first slots, and a second core including second slots. The permanent magnets are received in the corresponding first and second slots. The first core includes a first portion between first slots adjacent in a circumferential direction. The second core includes a second portion between second slots adjacent in the circumferential direction. The first portion has a dimension smaller than a dimension of the second portion in the circumferential direction.
HIGH POWER COMPACT CORDLESS CHAINSAW
A chainsaw configured to be powered by a battery pack. The chainsaw includes a housing, a guide bar, and a power and drive assembly. The housing includes a battery interface for receiving the battery pack. The guide bar guides a cutting chain and is removably coupled to the housing. The power and drive assembly includes a motor and a gear train. The motor is disposed within the housing and is configured to be powered by the battery pack. The gear train is driven by the motor and configured to drive the cutting chain. The housing, the guide bar, and the power and drive assembly each contribute to a total weight of the chainsaw. A power output by the power and drive assembly compared to the total weight defines a power-to-weight ratio of above 150 Watts per Pound.
HIGH POWER COMPACT CORDLESS CHAINSAW
A chainsaw configured to be powered by a battery pack. The chainsaw includes a housing, a guide bar, and a power and drive assembly. The housing includes a battery interface for receiving the battery pack. The guide bar guides a cutting chain and is removably coupled to the housing. The power and drive assembly includes a motor and a gear train. The motor is disposed within the housing and is configured to be powered by the battery pack. The gear train is driven by the motor and configured to drive the cutting chain. The housing, the guide bar, and the power and drive assembly each contribute to a total weight of the chainsaw. A power output by the power and drive assembly compared to the total weight defines a power-to-weight ratio of above 150 Watts per Pound.
System for Protecting an Operator of a Power Tool
A system for protecting an operator (110) of a power tool may include a first set of wearable sensors (120) worn by the operator (110), a second set of wearable sensors (130) worn by the operator (110), a first tool sensor (122) disposed at the power tool where the first tool sensor (122) is configured to communicate with the first set of wearable sensors (120), a second tool sensor disposed (132) at the power tool where the second tool sensor (132) is configured to communicate with the second set of wearable sensors (130), and a controller (140). The controller (140) may be configured to determine, based on distances between the first tool sensor (122) and the first set of wearable sensors (120) and between the second tool sensor (132) and the second set of wearable sensors (130), whether to initiate a protective action with respect to the power tool.
ELECTRIC WORK MACHINE
A brushless motor is at least partially located in a hermetically sealed space. An electric work machine includes a brushless motor, an output unit, a motor case, a lead wire, and a first seal. The brushless motor includes a stator, a rotor rotatable with respect to the stator, and a rotor shaft fixed to the rotor. The output unit is drivable by the rotor shaft. The motor case includes an internal space and a wiring passage. The internal space accommodates the stator and the rotor. The lead wire is located in the wiring passage connecting the internal space and an external space of the motor case. The first seal seals between the lead wire and the motor case.
ELECTRIC WORK MACHINE
A brushless motor is at least partially located in a hermetically sealed space. An electric work machine includes a brushless motor, an output unit, a motor case, a lead wire, and a first seal. The brushless motor includes a stator, a rotor rotatable with respect to the stator, and a rotor shaft fixed to the rotor. The output unit is drivable by the rotor shaft. The motor case includes an internal space and a wiring passage. The internal space accommodates the stator and the rotor. The lead wire is located in the wiring passage connecting the internal space and an external space of the motor case. The first seal seals between the lead wire and the motor case.
ELECTRIC WORK MACHINE
An electric work machine is drivable appropriately when a brushless motor generates heat. The electric work machine includes a brushless motor including a stator, a rotor rotatable with respect to the stator, and a rotor shaft fixed to the rotor, an output unit drivable by the rotor shaft, a motor case accommodating the stator and the rotor, and a cooling fan located outside the motor case and rotatable by the rotor shaft.
ELECTRIC WORK MACHINE
An electric work machine is drivable appropriately when a brushless motor generates heat. The electric work machine includes a brushless motor including a stator, a rotor rotatable with respect to the stator, and a rotor shaft fixed to the rotor, an output unit drivable by the rotor shaft, a motor case accommodating the stator and the rotor, and a cooling fan located outside the motor case and rotatable by the rotor shaft.
Gardening and/or forestry apparatus
A gardening and/or forestry apparatus has a support element. The support element supports an eyelet. The eyelet is configured to incorporate an apparatus securing element. The gardening and/or forestry apparatus also has an element receiving device. The support element and the element receiving device are configured to receive the support element in the element receiving device either in a first rotational position or in a second rotational position differing from the first rotational position and to secure the support element against rotation by form-fitting to the element receiving device.
ELECTRIC WORK MACHINE
An electric work machine (1) includes: a brushless motor having a stator disposed around a rotor (30); and an output part driven by the rotor. The rotor has a rotor core (31) and first and second magnetic-pole parts (34S, 34N) disposed around a circumferential direction of the rotor core. When the induced voltage of the brushless motor is given as Va, the power-supply voltage of the brushless motor is given as Vb, the rotational speed of the brushless motor is given as ω, a first induced voltage constant, which is expressed by Va/ω, is given as Ea [V/krpm], a pole-pairs count, which is the number of the first magnetic-pole parts or the second magnetic-pole parts, is given as Pi, and a second induced voltage constant, which is expressed as Ea/Pi, is given as Eb [V/krpm pole-pairs count], the motor satisfies the condition: Eb≤0.025×Vb.