scispace - formally typeset

Patent

Electronic switching module for a power tool

21 May 2012-

Abstract: A power tool includes a tool housing, an electric motor inside the housing, and a power interface facilitating a connection to a power source. At least four actively-controlled power components are configured as an H-bridge to modulate a supply of power from the power interface to the electric motor. A user-actuated input unit outputs a first signal indicative of a desired power output level to the electric motor and a second signal indicative of a desired direction of current flow to the electric motor. A control unit controls the supply of power to the electric motor using two of said power components with synchronous rectification for pulse-width modulation (PWM) of the supply of power based on the first signal, and to control the direction of current flow to the electric motor using the other two of said power components based on the second signal.
Topics: Single-phase electric power (70%), Power factor (67%), Switched-mode power supply (65%), Universal motor (63%), DC motor (62%)
Citations
More filters

Patent
Kazutaka Iwata1, Toshiaki Koizumi1Institutions (1)
10 Mar 2014-
Abstract: An electric power tool includes: a brushless motor having a plurality of stator windings and configured to rotate in accordance with voltages applied to the plurality of stator windings, an induced voltage being generated in accordance with a rotation of the brushless motor; a rectifier circuit configured to rectify an AC voltage; a smoothing capacitor configured to smooth the AC voltage rectified by the rectifier circuit to a pulsation voltage having a maximum value larger than the induced voltage and a minimum value smaller than the induced voltage; and an inverter circuit configured to perform switching operations to output the pulsation voltage to the plurality of stator windings by rotation.

490 citations


Patent
31 Jan 2013-
Abstract: A power tool includes a housing, a motor, an output member driven by the motor, and a reaming attachment coupled to the output member. The reaming attachment has a front end portion selectively driven in rotation by the output member to drive a fastener into a workpiece, and a reaming portion selectively driven in rotation by the output member to remove material from an end surface of a conduit. A rotational motion sensor in the housing is operable to detect rotational motion of the housing about an axis. A controller receives a signal indicative of rotational motion from the sensor, determines a direction of the rotational motion of the housing, and drives the motor in a direction corresponding to the direction of rotational motion of the housing.

352 citations


Patent
18 May 2015-
Abstract: A power tool system includes a first power tool having a first power tool rated voltage, a second power tool having a second power tool rated voltage that is different from the first power tool rated voltage, and a first battery pack coupleable to the first power tool and to the second power tool. The first battery pack is switchable between a first configuration having a first battery pack rated voltage that corresponds to the first power tool rated voltage such that the first battery pack enables operation of the first power tool, and a second configuration having a convertible battery pack rated voltage that corresponds to the second power tool rated voltage such that the battery pack enables operation of the second power tool.

68 citations


Patent
22 Jan 2013-
Abstract: Cordless power tools include a pistol housing having an upper portion that merges into a downwardly extending handle, a DC motor residing in the upper portion of the housing, the DC motor having a rotor that drives an output shaft; a torque transducer on board the tool in communication with the output shaft; and a dynamic motor control circuit residing in the housing in communication with the motor and torque transducer. The dynamic motor control circuit includes a Kelvin resistor in communication with the motor for measuring motor current and digital hall switches in communication with the motor for measuring motor speed. The motor current can vary by at least 100 A during operation.

66 citations


Patent
15 May 2012-
Abstract: An electric power tool is provided that includes a motor as a driving source, a first operation switch, a first semiconductor switch, and a second semiconductor switch. The first operation switch is operated by a user to be turned ON/OFF. The first semiconductor switch, provided on a current path from the power source to the motor, includes at least one semiconductor switching device. When the first operation switch is OFF, the first semiconductor switch is turned OFF to interrupt the current path. When the first operation switch is ON, the first semiconductor switch is turned ON to close the current path. The second semiconductor switch is provided on the current path in series with the first semiconductor switch and includes at least one semiconductor switching device. The second semiconductor switch closes/interrupts the current path by being turned ON/OFF in accordance with an input control signal.

49 citations


References
More filters

Patent
Indu B. Maiti1, Robert J. Shepperd1Institutions (1)
06 Aug 1996-
Abstract: The isolation, modification and use of wild-type and modified viral FLt promoters of peanut chlorotic streak caulimovirus (PClSV) in the expression of chimeric genes in plant cells. The FLt promoter from PClSV has been modified to have duplicated enhancer domains.

767 citations


Patent
29 Apr 1998-
Abstract: A surgical power tool is disclosed including a power console and a handheld motor unit. The power console provides controlled power and to the handheld motor unit. Pressure sensitive switching elements on the handheld unit provide signals to the power console which are transformed into operating power to the motor unit including variable speed, speed range, forward/reverse, and safety. The handheld motor unit includes a chuck or tool receptacle and a Hall effect or other radiation field detector which response to the presence of a magnet or other radiation device as a part of the surgical tool, to identify the tool installed and provide a control signal to the motor, e.g., speed range limitation. The handheld motor unit housing is sealed and autoclavable. The housing for the handheld unit includes a flexible wall section lying over pressure sensitive switches and variable resistance whereby the surgeon's finger pressure on discrete portions of the flexible wall provide motor control including speed control, direction of operation, speed range selection and a SAFE, i.e., locked off position. Multiple handheld motor units may be simultaneously operated and controlled individually by their handheld controls or selectively by the power supply and control unit. Footswitch control is also disclosed.

576 citations


Patent
22 Oct 2004-
Abstract: A method and apparatus for braking a motor has a braking circuit that intermittently shorts the windings of the motor to brake the motor. The braking circuit is powered by back EMF generated by the motor when power is disconnected from the motor.

561 citations


Patent
27 Oct 2006-
Abstract: A battery pack which includes a battery pack electronic control circuit adapted to control an attached power tool and/or an attached charger. The battery pack includes additional protection circuits, methodologies and devices to protect against fault conditions within the pack, as the pack is operatively attached to and providing power to the power tool, and/or as the pack is operatively attached to and being charged by the charger.

452 citations


Patent
09 Jul 2001-
Abstract: A control system for driving a power tool is provided comprising a power source, a motor adapted to drive a shaft, a power switching unit interconnecting the power source and the motor, and a controller The power switching unit applying a pulse width modulated (PWM) drive signal from the power source to the motor The controller monitoring at least one electrical characteristic of at least one of the power source, motor and power switching unit and adjusting the operating duty cycle of the PWM drive signal based on the electrical characteristics

373 citations


Network Information
Related Papers (5)
22 May 2003

Kai Chi Chan, Man Ting Ho

11 Oct 2006

Samuel G. Woods, Mike Forster +6 more

11 Aug 1986

William R. Lessig, Dale K. Wheeler +2 more

22 Jan 2013

Michael R. Wood, Jr. William M. Ball +1 more

Performance
Metrics
No. of citations received by the Paper in previous years
YearCitations
20212
20207
20194
20183
20178
201611