B25D2250/201

ELECTRIC POWER TOOL AND METHOD OF CONTROLLING ROTATIONAL SPEED OF MOTOR IN ELECTRIC POWER TOOL

An electric power tool according to one aspect of the present disclosure includes a main body, a motor, a tool holder configured to hold a tool bit, a hammer, a motion converter, a rotation transmitter, a first load detector, a second load detector, and a motor controller. The first load detector detects, based on information indicating a drive state of the motor, a load imposed from a work piece to the tool bit. The second load detector detects, based on information indicating a behavior of the main body, a load imposed from the work piece to the tool bit. The motor controller sets an upper limit of rotational speed of the motor to a predetermined no-load rotational speed in response to no-load on the tool bit being detected by both the first load detector and the second load detector.

ELECTRIC POWER TOOL AND METHOD OF ASSEMBLING ELECTRIC POWER TOOL

An electric power tool in one aspect of the present disclosure includes a housing; a motor; an output shaft; a rotation transmission; a motor controller; and a twisted-motion detector. The twisted-motion detector is disposed in the housing independently from the motor controller. The twisted-motion detector detects a twisted-motion of the housing in the circumferential direction of the output shaft and outputs a result of the detection to the motor controller.

Method for the open-loop and closed-loop control of a power tool

Handle apparatus on a power tool, in particular a chipping hammer, having a drive, a control device, a transmission device, wherein the handle apparatus contains a lever element that is pivotable relative to a housing of the power tool. The lever element is movable reversibly relative to the housing of the power tool by exertion of a force in one direction, and a sensor device is contained for sensing at least one first or second position of the lever element relative to the housing of the power tool, wherein a first rotational speed value for the drive is settable depending on the first sensed position of the lever element relative to the housing of the power tool or at least one second rotational speed value for the drive is settable depending on the second sensed position of the lever element relative to the housing of the power tool.

Kickback control methods for power tools

Kickback control methods for power tools. One power tool includes a movement sensor configured to measure an angular velocity of the housing of the power tool about the rotational axis. The power tool includes an electronic processor coupled to the switching network and the movement sensor and configured to implement kickback control of the power tool. To implement the kickback control, the electronic processor is configured to control the switching network to drive the brushless DC motor, receive measurements of the angular velocity of the housing of the power tool from the movement sensor, determine that a plurality of the measurements of the angular velocity of the housing of the power tool exceed a rotation speed threshold, and control the switching network to cease driving of the brushless DC motor in response to determining that the plurality of the measurements of the angular velocity exceed the rotation speed threshold.

ROTARY POWER TOOL

A rotary hammer tool can include a housing, a first motor supported by the housing, a spindle rotated by the first motor, a second motor supported by the housing, and a reciprocation mechanism reciprocated by the second motor. The reciprocation mechanism can include a piston driven to reciprocate within the spindle and a striker to reciprocate within the spindle in response to reciprocation of the piston. The rotational speed of the spindle and a reciprocation frequency of the reciprocation mechanism may be independently controllable.

OPERATING MODE DETECTION SYSTEM FOR ROTARY HAMMER

A rotary hammer includes a housing and a mode selection dial supported in the housing. The mode selection dial includes a cam. The housing supports a motor providing a rotational output. The housing supports a linkage moveable between a first position and a second position in response to engagement by the cam. A loss-of-control detection system measures acceleration of the housing and disables the motor upon the acceleration exceeding an acceleration threshold. The housing supports an operating mode detection system including a magnet and a Hall-effect sensor. The magnet is coupled to the linkage and moveable therewith between a third position corresponding to the first position of the linkage and a fourth position corresponding to the second position of the linkage. The Hall-effect sensor provides an output signal indictive of the position of the magnet. The loss-of-control detection system is selectively disabled based upon the output signal.

Non-contact speed selector switch in rotary power tool

A rotary power tool includes a housing having a motor housing portion and a handle portion extending therefrom. An electric motor is positioned within the motor housing portion. The rotary power tool further includes a trigger switch configured to activate and deactivate the motor. The rotary power tool further includes a non-contact speed selector switch that is separate from the trigger switch and configured to adjust a rotational speed of the motor. The non-contact speed selector switch is positioned in a foot of the handle portion opposite the motor housing portion.

NON-CONTACT SPEED SELECTOR SWTICH IN ROTARY POWER TOOL

A power tool includes a housing having a motor housing portion and a handle portion extending therefrom. An electric motor is positioned within the motor housing portion. The power tool also includes trigger switch configured to activate and deactivate the motor. The power tool further includes a non-contact mode selector switch that is separate from the trigger switch and configured to adjust an operational mode of the tool. The non-contact mode selector switch is positioned in a foot of the handle portion opposite the motor housing portion.

Power tool

A hammer drill (100) comprises an electric motor (110), a piston (127) as a driving member and a controller (199) which controls and drives the electric motor (110). The piston (127) is reciprocated by rotation of the electric motor (110) and thereby a hammer bit (119) is driven in its longitudinal direction. The hammer bit (119) is moved forward in response to a forward movement stroke of the piston (127) and thereby a hammering operation is performed by the hammer bit (119). The controller (199) sets a duty ratio of a driving pulse signal which drives the electric motor (110) in the forward movement stroke of the piston (127) to be larger in order to prevent a reduction of a rotation speed of the electric motor (110) due to a load applied on the electric motor (110) during the forward movement stroke of the piston (127).

Method for controlling and regulating a machine tool and handle for machine tool

Method for the open-loop and closed-loop control of a power tool, in particular a chipping hammer, having a drive, a control device, a sensor device, a transmission device and a handle apparatus, wherein the handle apparatus contains a lever element with a signal transmitter, said lever element being pivotable relative to the sensor device. The method includes: sensing a first and second position of the signal transmitter by the sensor device; determining an acceleration of the signal transmitter from the first position to the second position by the control device; setting a first rotational speed for the drive by the control device for the output of a first impact energy value of the transmission device when the determined acceleration reaches a first predetermined threshold value or setting a second rotational speed for the drive by the control device for the output of a second impact energy value of the transmission device when the determined acceleration reaches a second predetermined threshold value. A handle apparatus on a power tool, in particular a chipping hammer, is also provided.