H02K7/145

Power tool with compact motor assembly

A power tool is provided with a tool housing, a support plate provided within the tool housing, a rear tool cap mounted on a rear end of the tool housing, and a brushless direct-current (BLDC) motor received within the housing. The motor includes a stator assembly having a stator core and stator windings, a front motor bearing supported by the support plate, a rear motor bearing supported by the rear tool cap, and a rotor including a rotor core and a magnet ring mounted around the rotor core. The rotor core defines an annular recess within which at portion of the front bearing and a portion of the support plate are located such that the a radial plane intersects the front bearing, the magnet ring, and the stator core.

Kickback control methods for a power tool including a force sensor

A power tool including a housing, a motor having a rotor and a stator, at least one grip sensor configured to generate a grip parameter, and a switching network electrically coupled to the brushless DC motor. An electronic processor is connected to the switching network and the at least one grip sensor and configured to implement kickback control of the power tool. The electronic processor is configured to determine a kickback threshold based on the grip parameter, control the switching network to drive the motor, receive a signal related to a power tool characteristic, determine, based on the power tool characteristic being greater than or equal to the kickback threshold, that a kickback event of the power tool is occurring, and control, in response to determining that the kickback event is occurring, the switching network to cease driving of the motor.

Electric sander motor
11554459 · 2023-01-17 · ·

An electric sander motor includes a motor main body (100), a power axial shaft (210) and a sleeve (220). The motor main body (100) includes a rotor (110) and a stator (120) surrounding the rotor (110). The power axial shaft (210) includes an axial hole (211) extending along a central axis of the power axial shaft (210). The sleeve (220) includes one open end and another closed end extended outward to form an eccentric axial shaft (221) penetrating through the axial hole (211). A central axis of the eccentric axial shaft (211) is parallel with a central axis of the sleeve (220) and spaced apart therefrom. The power axial shaft (210) penetrates through the rotor (110), and the sleeve (220) is outside the motor main body (100). The assembly is facilitated by assembling the power axial shaft (210) and the sleeve (220) onto the motor main body (100) sequentially.

Power tool and method
11697200 · 2023-07-11 · ·

A power tool, including a support structure, a pivot bearing arranged on the support structure, a shaft mounted on the support structure via the pivot bearing, a rotatable tool coupled to the shaft, in particular a saw blade, milling cutter or grinding wheel, a strain gauge arrangement for detecting a mechanical quantity which depends on a force emanating from the tool, and a control device which is adapted to recognize an event and/or a state of the power tool according to the detected mechanical quantity. The strain gauge arrangement is arranged on a stationary structure section coupled in a force-transmitting manner to the pivot bearing and is not arranged on the pivot bearing.

ELECTRIC DRILL AND ELECTRIC TOOL
20230007837 · 2023-01-12 ·

An electric drill and an electric tool, including: a housing provided with an air inlet and an air outlet; a motor received in the housing, wherein the motor at least comprises a motor shaft; a drill bit, acting on a workpiece; the motor shaft is connected to the drill bit; a gearbox arranged in the housing for accommodating the transmission assembly; a fan supported by the motor shaft; wherein the gearbox is formed with a passage, and at least a part of a flow path of an airflow that enters the housing from the air inlet and flows out of the housing from the air outlet is provided on the passage.

HANDHELD POWER TOOL WITH BRUSHLESS ELECTRIC MOTOR

A power tool is provided including a housing defining a cavity therein, where the housing includes a motor case and a handle portion extending along a longitudinal axis of the housing from the motor case; an electric motor having a drive shaft and mounted within the motor case; a partitioning wall extending radially and separating the motor case portion from the non-motor case portion of the housing; and a bearing pocket with an open end facing the motor case portion formed in the partitioning wall and a main body extending away from the electric motor for receiving a rotor bearing. The handle portion includes two elongate walls extending from the partitioning wall, a circuit board supported by the two elongate walls and including a motor drive circuit, and two covers secured to the two elongate walls to cover the circuit board.

Electric pulse tool

An electric pulse tool is configured to deliver torque in pulses on an output shaft thereof and includes an electric motor to drive the output shaft. The electric pulse tool is configured to, for each period, provide a current pulse to the electric motor during a current-on time interval, pause a current feed to the electric motor after the current-on time interval until an end of a torque pulse, determine a width of the torque pulse, and continue pausing the current feed to the electric motor during a pause interval from the end of the torque pulse. The pause interval is determined based on the width of the torque pulse such that a wider torque pulse results in a wider pause interval and a narrower torque pulse results in a shorter pause interval.

ELECTRIC WORK MACHINE
20230216359 · 2023-07-06 · ·

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.

Power tool

A power tool includes a case, a motor, a plurality of Hall effect sensors, a first circuit board, and a second circuit board. The Hall effect sensors detect a position of a rotor of the motor and correspondingly generate position signals. A plurality of commutating switches and a first controller are disposed on the first circuit board. A second controller is disposed on the second circuit board, and could transmit a driving signal to the first controller according to the operating signal of an operator interface. The first controller regulates the commutating switches to commutate according to the driving signal and the position signals, thereby to activate the rotor to rotate. With such design, a commutation process and a user operating process are regulated by the two different controllers, which could efficiently simplify the program code installed in each of the controllers and facilitate the maintenance of the controllers.

Brushless motor system for power tools

A power tool is provided including a gear case having a spindle, a motor case connected to a rear end of the gear case along a longitudinal axis; a handle portion extending from a rear end of the motor case along the longitudinal axis; a motor housed inside the motor case; a fan in rotational connection with the motor; at least one air intake arranged at least one of the motor case or the handle portion near the rear end of the motor case; and a power module including power switches for driving the motor and a heat sink. The power module is housed in at least one of the motor case or the handle portion near the rear end of the motor case such that rotation of the fan causes air flow to enter through the air intake and flow near the heat sink and through the motor.