With Speed Responsive Governor Patents (Class 173/179)
  • Patent number: 11440166
    Abstract: An impact tool and method can include: a motor; a trigger; a controller configured to control driving power supplied to the motor using a semiconductor switching element according to an operation of the trigger; a striking mechanism configured to drive a tip tool continuously or intermittently by rotation force of the motor, the striking mechanism including a hammer and an anvil. The controller drives the semiconductor switching element at a high duty ratio when the trigger is manipulated. The motor can be driven so that the duty ratio is lowered before a first striking of the hammer on the anvil is performed and the first striking is performed at a low duty ratio lower than the high duty ratio.
    Type: Grant
    Filed: February 16, 2020
    Date of Patent: September 13, 2022
    Assignee: KOKI HOLDINGS CO., LTD.
    Inventors: Kazutaka Iwata, Yoshihiro Komuro
  • Patent number: 10099303
    Abstract: An electric power tool includes a brushless motor, a control unit configured to control power supply to the brushless motor, a rotary tool configured to be rotated by the brushless motor, a rotation speed detecting unit configured to detect a rotation speed of the brushless motor, a main switch configured to transmit, to the control unit, an ON/OFF signal for switching between driving and stopping of the brushless motor, and a mode switching unit configured to transmit, to the control unit, a mode switching signal for switching between multiple modes of rotation control of the brushless motor, the control unit is configured to perform the rotation control of the brushless motor in any one of the multiple modes including at least a high-speed mode and a low-speed mode.
    Type: Grant
    Filed: August 4, 2014
    Date of Patent: October 16, 2018
    Assignee: HITACHI KOKI CO., LTD.
    Inventors: Kenichirou Yoshida, Akira Onose, Shinji Kuragano
  • Patent number: 10070756
    Abstract: A kitchen appliance has a power switch for controlling supply of power to a motor and a separate control circuit (18) for controlling the speed. A button (14) for control by the user is provided for controlling both the actuation and speed. A carrier (40) carries the button, and also carries a first actuator (44, 86) for mechanically actuating the power switch when the button is first moved. When the button is further moved, the motor speed is controlled.
    Type: Grant
    Filed: November 25, 2014
    Date of Patent: September 11, 2018
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventors: Walter Alex Planegger, Mario Hosner, Joze Dermol
  • Publication number: 20150122525
    Abstract: An electric tool for outputting torque includes a housing and a motor disposed in the housing, a rotatable base configured to be driven by the motor to rotate about a first axis, at least one impact block rotatably connected to the rotatable base, an output shaft rotatably connected in the housing and configured to rotate about the first axis under intermittent impact of the impact block, a locking member which, when at a first position, locks the impact block to prevent it from impacting on the output shaft and which, when at a second position, releases the impact block to allow it to rotate freely, a biasing assembly for biasing the locking member to the first position, a regulating assembly for regulating a biasing degree exerted by the biasing assembly on the locking member, and a control assembly operable by the user from outside the housing to control the regulating assembly. The locking member is disposed at least partially in the rotatable base.
    Type: Application
    Filed: October 29, 2014
    Publication date: May 7, 2015
    Inventors: Gan Wei, Wu Chen
  • Patent number: 8985237
    Abstract: A power screwdriver is disclosed, having a drive for driving a tool spindle having a controller for controlling the drive, having a monitoring device for monitoring the rotation speed or the torque, and having a monitoring device for monitoring a switch-off criterion, which monitoring device is coupled to the controller, in order to switch off the drive when the switch-off criterion is reached, with the controller being programmed such that (a) the drive is first of all accelerated until the rotation speed has reached a specific first rotation speed; (b) if the rotation speed then falls by at least a specific amount within a specific time increment, or the torque rises by at least a specific amount within a specific time increment, the drive is braked until the rotation speed has reached a specific second rotation speed, which is lower than the first rotation speed; (c) the drive is then regulated at the second rotation speed for a specific time; and (d) after step (c), the drive is accelerated again at most
    Type: Grant
    Filed: June 17, 2011
    Date of Patent: March 24, 2015
    Assignee: C. & E. Fein GmbH
    Inventor: Michael Kaufmann
  • Publication number: 20150047866
    Abstract: An electric tool in which a pulsating input voltage is configured to be supplied to a drive circuit of a motor, the electric tool including: a rotation speed detection unit configured to detect a rotation speed of the motor, characterized in that the electric tool further includes: a control part configured to vary a determining value for determining whether the rotation speed of the motor satisfies a predetermined condition or not, so as to be synchronous with a pulsation cycle of the input voltage supplied to the drive circuit.
    Type: Application
    Filed: March 29, 2013
    Publication date: February 19, 2015
    Applicant: HITACHI KOKI CO., LTD.
    Inventors: Hironori Sakai, Naoki Tadokoro, Kazutaka Iwata
  • Patent number: 8931576
    Abstract: A power tool has a motor, a power supply unit, a trigger unit, a control unit, and a motor load detection unit. The power supply unit supplies power to the motor. The trigger unit causes the power supply unit to start applying a voltage to the motor. The control unit controls the power supply unit to increase the voltage to the motor at a constant increasing rate. The motor load detection unit detects a motor load. The control unit changes the constant increasing rate in accordance with the motor load.
    Type: Grant
    Filed: May 17, 2011
    Date of Patent: January 13, 2015
    Assignee: Hitachi Koki., Ltd.
    Inventor: Kazutaka Iwata
  • Publication number: 20140352995
    Abstract: An object of the present invention is to provide an electric power tool capable of automatically changing the rotating speed of an electric motor in accordance with operation conditions. The electric power tool 11 which carries out an operation of polishing, peel-off, cutting, or the like by swinging a tip tool 13 attached to a tool retaining part 31 within the range of predetermined angles by the drive power of the electric motor 12, wherein the electric power tool has a control device configured to indirectly detect the load of the tip tool from a current value, and to control the rotating speed of the electric motor 12 to a maximum rotating speed and a minimum rotating speed on the basis of the load of the tip tool 13.
    Type: Application
    Filed: May 30, 2014
    Publication date: December 4, 2014
    Applicant: Hitachi Koki Co., Ltd.
    Inventors: Kenichi MATSUNAGA, Yoshikazu KAWANO
  • Patent number: 8807239
    Abstract: A handheld power tool has a switchable gear having at least two gear stages which are engaged via an adjustable switching member, the switching member being held in a latching position with a latching member in a first gear stage and in an unlatched position in a second gear stage. The latching member is rotatably mounted in the housing within a limited angular section between two end stop positions.
    Type: Grant
    Filed: August 12, 2009
    Date of Patent: August 19, 2014
    Assignee: Robert Bosch GmbH
    Inventor: Heiko Roehm
  • Patent number: 8689900
    Abstract: A rotary tool includes an externally operable operation switch; a motor serving as a power source; a power transfer block for transferring the rotation of the motor; a load detection unit for detecting an amount of load of the motor; and a control unit for controlling the motor. The control unit is configured to perform an operation control by which the motor is controlled so that a rotation speed of the motor is increased in proportion to the operation amount of the operation switch and a feedback control by which the rotation speed of the motor is controlled depending on the detection result of the load detection unit. The control unit inhibits the feedback control during the time when the operation amount of the operation switch is equal to or less than a threshold and performing the feedback control only when the operation amount of the operation switch is greater than the threshold.
    Type: Grant
    Filed: November 23, 2010
    Date of Patent: April 8, 2014
    Assignee: Panasonic Corporation
    Inventors: Tatsuya Miwa, Masaki Ikeda
  • Patent number: 8678105
    Abstract: A plug arrangement in a machine tool comprises a primary plug part, which is associated with a drive motor, and a secondary plug part. According to the invention the primary and secondary plug parts are assembled to form a common plug part.
    Type: Grant
    Filed: March 19, 2009
    Date of Patent: March 25, 2014
    Assignee: Robert Bosch GmbH
    Inventors: Michael Habele, Marcus Schuller
  • Publication number: 20140034346
    Abstract: A speed control device for limiting the idle and operating speed of a pneumatic power tool driven by an air turbine (20) and comprising an inlet passage (16) for supplying pressure air at a pressure (P1), one or more nozzles (25) for directing supplied motive pressure air onto the turbine wheel (22) of the air turbine (20), and a speed governor (21) with a movable valve element (43) biased by a turbine speed responsive control pressure (P3) and arranged to control the flow of supplied pressure air from the pressure air inlet passage (16) to the nozzles (25), wherein a pressure regulator (60) controlled by the pressure air supply pressure (P1) is arranged to adjust the control pressure (P3) by adjusting the size of a bleed passage (66) communicating with the atmosphere in response to the actual level of the pressure air supply pressure (P1) such that a decreasing pressure air supply pressure (P1) results in an decreased area of the bleed passage (66) and a following increased control pressure which results in
    Type: Application
    Filed: April 13, 2012
    Publication date: February 6, 2014
    Applicant: ATLAS COPCO INDUSTRIAL TECHNIQUE AB
    Inventors: Dan Eklund, Ulf Mikael Eriksson
  • Patent number: 8616299
    Abstract: A motor control device includes a target value setting unit, a measuring unit, a deviation calculating unit, a proportional control unit, an integral control unit, and a disabling unit. The deviation calculating unit calculates a deviation between a target value, set by the target value setting unit, and a measured value for rotational speed, measured by the measuring unit. The disabling unit disables proportional control, performed by the proportional control unit, when the deviation, calculated by the deviation calculating unit, is a value within a predetermined range.
    Type: Grant
    Filed: January 25, 2011
    Date of Patent: December 31, 2013
    Assignee: Makita Corporation
    Inventor: Yoshitaka Ichikawa
  • Patent number: 8544559
    Abstract: A portable power tool having a housing with a rotation motor for powering a working implement, wherein sensors are provided to indicate the motor speed and the power supply, and a programmable evaluation unit is arranged to compare indicated speed and pressure values with stored limit values, and to accumulate the total operation time of the power tool and compare that with preset time limits for tool service intervals, and an optical information unit is provided on the housing to indicate whether those stored limit values have been reached.
    Type: Grant
    Filed: February 12, 2009
    Date of Patent: October 1, 2013
    Assignee: Atlas Copco Industrial Technique Aktiebolag
    Inventors: John Robert Christian Friberg, Anders Urban Nelson
  • Publication number: 20130199812
    Abstract: A handheld work apparatus has a combustion engine (4) for driving a tool. The combustion engine (4) has an ignition device, a device for metering fuel and a control device (31). The control device (31) engages when an engagement speed (nE1, nE2) is reached, in order to limit the speed (n) of the combustion engine (4). In order to allow the speed (n) to be set in an easy manner at full throttle, the work apparatus has a device for setting the engagement speed (nE2) by the user.
    Type: Application
    Filed: February 4, 2013
    Publication date: August 8, 2013
    Applicant: ANDREAS STIHL AG & CO. KG
    Inventor: Andreas Stihl AG & Co., KG
  • Publication number: 20120222876
    Abstract: An installation method for an expansion anchor is carried out by repeatedly exerting rotary-percussive strikes onto the shank (2) of the expansion anchor (1) by an impact screwdriver. The repeat rate (Ntarget) of the rotary-percussive strikes is selected as a function of the tightening torque prescribed for expanding the expansion sleeve (3) of the expansion anchor (1). The impact screwdriver stops generating rotary-percussive strikes when the detected mean rotational speed (d) of the shank falls below a threshold value (D).
    Type: Application
    Filed: February 27, 2012
    Publication date: September 6, 2012
    Applicant: Hilti Aktiengesellschaft
    Inventors: Peer Schmidt, Joerg Appl, Servey Khandozhko
  • Patent number: 8172003
    Abstract: A portable device having an overload protection device for motor-operated tools has a drive motor, a drive shaft connected to the drive motor and driven in rotation by the drive motor, and an output shaft for driving a cutting tool, wherein the output shaft is arranged substantially perpendicularly to the drive shaft. A drive pinion is connected to the drive shaft. A drum is supported on the output shaft and driven in rotation by the drive pinion. A coupling is arranged between the drum and the output shaft and engages the drum. The coupling is connected to the output shaft. When the output shaft is blocked, the coupling effects an automatic decoupling between the drum and the output shaft in order to prevent overloading of the drive motor.
    Type: Grant
    Filed: October 15, 2004
    Date of Patent: May 8, 2012
    Assignee: Atlas Copco Electric Tools GmbH
    Inventors: Thomas Robieu, Jean-Claude Maret
  • Patent number: 8083007
    Abstract: An electric power tool includes a motor, a speed reducer unit arranged to deliver the rotational power of the motor and provided with gears, a housing arranged to accommodate the motor and the speed reducer unit, and a speed changing unit for changing a gear reduction ratio of the speed reducer unit. The speed changing unit is arranged in such a position as to be operable outside the housing. The speed changing unit includes an operation lever slidingly operable in a speed changing direction when pushed, an operation detector unit for detecting the operation lever to control electric power supplied to the motor, a shift unit for changing the gear reduction ratio of the speed reducer unit in response to sliding movement of the operation lever, and a slide restraint unit for restraining the sliding operation of the operation lever until the operation detector unit detects the operation lever.
    Type: Grant
    Filed: March 24, 2009
    Date of Patent: December 27, 2011
    Assignee: Panasonic Electric Works Co., Ltd.
    Inventors: Kenichiro Inagaki, Fumiaki Sekino, Yutaka Yamada
  • Patent number: 7936142
    Abstract: A drilling device prevents recurrence of an overload condition after occurrence of the overload condition, thereby improving operability and safety in the drilling device. A motor for rotating a drill is connected to an AC power source through a motor control unit, a current detector, and a power switch. A magnet is also connected to the AC power source through the power switch and a full-wave rectifier. The motor control unit rotationally drives the motor on the basis of a signal sent from a main control unit according to a state in which a motor start switch is on. The main control unit controls the motor control unit to gradually reduce a supply voltage to the motor when the motor becomes overloaded, to gradually increase the voltage to the normal power supply condition when the overload condition is vanished, and to stop power supply to the motor if the overload condition continues for a predetermined period.
    Type: Grant
    Filed: December 13, 2006
    Date of Patent: May 3, 2011
    Assignee: Nitto Kohki Co., Ltd.
    Inventors: Kenji Otsuka, Osamu Asano
  • Patent number: 7882899
    Abstract: A power tool comprising a housing, a motor, an output shaft, a gear transmission mechanism and a control system. The gear transmission mechanism is connected between the motor and the output shaft to transmit the rotary power of the motor to the output shaft. The gear transmission mechanism has a high speed position and a low speed position. The control system is coupled to the gear transmission mechanism for detecting an operating characteristic of the power tool to actuate a ring gear to automatically move from the high speed position to the low speed position and to reduce the rotational speed of the ring gear when the operating characteristic exceeding a predetermined value.
    Type: Grant
    Filed: August 26, 2008
    Date of Patent: February 8, 2011
    Assignee: Positec Power Tools (Suzhou) Co., Ltd
    Inventors: Gianni Borinato, Kelvin Wong, Shisong Zhang, Paolo Andriolo, Warren Brown, Hongfeng Zhong, Fangshi Liu, Chengzhong Chen
  • Patent number: 7730964
    Abstract: The invention relates to a power tool having a change-speed gear device comprising a plurality of gears (1, 2) for adjusting on demand power stages of a drive, wherein an overload protection can be coupled to the gears (1, 2). According to the invention, the device comprises at least one gear (3) in which the overload protection function can be forcibly deactivated. The invention also relates to an overload protection.
    Type: Grant
    Filed: July 3, 2006
    Date of Patent: June 8, 2010
    Assignee: Robert Bosch GmbH
    Inventors: Robert Simm, Cornelis Van Der Schans, Markus Weber
  • Patent number: 7681659
    Abstract: A control system is provided for use in a power tool. The control system includes: a rotational rate sensor having a resonating mass and a controller electrically connected to the rotational rate sensor. The rotational rate sensor detects lateral displacement of the resonating mass and generates a signal indicative of the detected lateral displacement, such that the lateral displacement is directly proportional to a rotational speed at which the power tool rotates about an axis of the rotary shaft. Based on the generated signal, the controller initiates a protective operation to avoid further undesirable rotation of the power tool. The controller may opt to reduce the torque applied to shaft to a non-zero value that enables the operator to regain control of the tool.
    Type: Grant
    Filed: January 14, 2008
    Date of Patent: March 23, 2010
    Assignee: Black & Decker Inc.
    Inventors: Qiang Zhang, Uday Deshpande, John Charles Vanko, Jason Lee, Craig Schell, Thomas Jay Bodine, Joao Norona, David Beers
  • Patent number: 7588098
    Abstract: An object of the present invention is to provide an electric screwdriver device having a function for determining that a correct tightening operation has been carried out when the tightening operation has taken a time longer than a reference time predetermined for the tightening operation, characterized in comprising a novel feature for determining the reference time.
    Type: Grant
    Filed: April 16, 2008
    Date of Patent: September 15, 2009
    Assignee: Nitto Kohki Co., Ltd.
    Inventors: Hiroyuki Nakazawa, Hideki Fujita
  • Publication number: 20090151968
    Abstract: A device for the high-speed drilling of boards for printed circuits and the like comprising a support (2), a drill head (11) with associated mandrel (12), and a device for locking and driving a bit (13) in the mandrel, wherein the mandrel is actuated by a compressed air turbine (33) and comprises means (40) for encoding the speed of rotation of the turbine adapted to generate a signal representing this speed, this signal being supplied to a control circuit (61) in order to drive a proportional valve (62) disposed in the circuit supplying compressed air to the turbine as a function of the speed of rotation encoded by the encoder means (40).
    Type: Application
    Filed: October 27, 2006
    Publication date: June 18, 2009
    Inventor: Gioachino Busatta
  • Patent number: 7475739
    Abstract: A power tool (10) with a housing (12) that includes a dust box (50, 150) and a motor (20) with air cooling, and a cooling exhaust-air duct (44, 46) and a chip suctioning duct (40) which guides a chip-suctioning flow can be used with improved performance and in an environmentally friendlier manner due to the fact that the cooling air flows across the dust box (50, 150) under favorable flow conditions, whereby the evacuation of dust into the dust box (50, 150) is improved and whirls of dust caused by cooling air in the tool region are prevented from forming.
    Type: Grant
    Filed: August 7, 2003
    Date of Patent: January 13, 2009
    Assignee: Robert Bosch GmbH
    Inventor: Steffen Wuensch
  • Patent number: 7410006
    Abstract: A control system is provided for use in a power tool. The control system includes: a rotational rate sensor having a resonating mass and a controller electrically connected to the rotational rate sensor. The rotational rate sensor detects lateral displacement of the resonating mass and generates a signal indicative of the detected lateral displacement, such that the lateral displacement is directly proportional to a rotational speed at which the power tool rotates about an axis of the rotary shaft. Based on the generated signal, the controller initiates a protective operation to avoid further undesirable rotation of the power tool. The control scheme employed by the power tool may initiate different protective operations for different tool conditions.
    Type: Grant
    Filed: October 19, 2005
    Date of Patent: August 12, 2008
    Assignee: Black & Decker Inc.
    Inventors: Qiang Zhang, Uday Deshpande, Shailesh P. Waikar, Daniel Puzio, Craig Schell, William F. Hilsher, Joshua D. West
  • Patent number: 7395874
    Abstract: A slaving and blocking device for transmitting a torque from a driving part to a driven part and for stopping the driven part at a torque engaging the driven part has a slaving unit fixable on the driving part fixed against relative rotation and having slaving claws that are offset from one another in a circumferential direction, a roller star wheel located in the slaving unit and connectable to the driven part fixed against relative rotation, clamping bodies located in freewheeling fashion between the slaving claws and points of a star of the roller star wheel, a stationary clamping ring located concentrically to the slaving means and the roller star wheel and having an inner annular face forming a counterpart clamping face for the clamping bodies, and radially displaceable centrifugal force elements located in the roller star wheel such that above a predetermined rpm the force elements clamp the roller star wheel firmly to the slaving means.
    Type: Grant
    Filed: November 14, 2005
    Date of Patent: July 8, 2008
    Assignee: Robert Bosch GmbH
    Inventor: Olivier Zeiter
  • Publication number: 20080093094
    Abstract: An air driven tool for use in a machining center, the air driven tool including an adjustable speed regulator and a turbine. The turbine is driven by pressurized air directed thereto. The turbine is rotatable about an axis. A flow of the air is regulated by the adjustable speed regulator. The adjustable speed regulator includes a biasing member, an inclined annular surface, a regulator plate and a plurality of moveable bearings. The inclined annular surface has an angle relative to the axis. The plurality of movable bearings are positioned between the inclined annular surface and the regulator plate. The biasing member biases the inclined annular surface and/or the regulator plate toward each other.
    Type: Application
    Filed: October 18, 2007
    Publication date: April 24, 2008
    Inventor: Steve M. Bryan
  • Patent number: 7334648
    Abstract: A impact power tool includes a motor rotating a drive shaft, an output shaft holding a tool bit, and a hammer coupled to the drive shaft. The hammer is rotatable together with the drive shaft and is engageable with an anvil fixed to the output shaft so as to give a rotary impact to the output shaft. The tool includes a speed commander generating a target speed intended by a user, and a speed detector for detection of a speed of the drive shaft. A speed controller generates a control signal for driving the motor by referring to the target speed and the detected speed. The speed controller provides a detection time frame, and to adopt a predefined pseudo-detection speed as a substitute for the detected speed when no speed detection is available within the detection time frame. Accordingly, even if no speed detection continues, i.e.
    Type: Grant
    Filed: June 28, 2006
    Date of Patent: February 26, 2008
    Assignee: Matsushita Electric Works, Ltd.
    Inventor: Tadashi Arimura
  • Patent number: 7090031
    Abstract: An intelligent tightening spindle comprises a drive output; a housing adapted to detachably mount to a moving platform of a multi-tool processing station, with the housing substantially enclosing: at least one electric drive motor having an associated servo amplifier; a gear unit operatively connecting the drive motor to the drive output; a spindle measurement transducer operative to monitor at least one of the drive motor, the gear unit, and the drive output; and a measurement data processing unit in communication with the spindle measurement transducer. An output signal port may have signals applied thereto representing measurement data that has been processed by the measurement data processing unit. The measurement transducer and/or the data processing unit may be removably coupled to the spindle via one or more electrical connectors. One or more of the tightening spindles may be used to form a multi-tool processing station.
    Type: Grant
    Filed: July 27, 2004
    Date of Patent: August 15, 2006
    Assignee: Cooper Power Tools GmbH & Co.
    Inventor: Ulrich Kaminski
  • Patent number: 7040414
    Abstract: A pneumatic tool includes a housing, a driving mechanism, a rear cap, a direction controller, a speed controller, and an operating member. The housing is formed with a component chamber and an intake passageway. The driving mechanism includes an output shaft rotatable about a rotary axis. The rear cap defines a cap chamber in spatial communication with the component chamber, and has a connecting passageway that intercommunicates the cap chamber and the intake passageway. The direction controller and the speed controller are mounted in the cap chamber for rotation about the rotary axis. The operating member is coupled to the direction controller, is accessible externally of the rear cap and the housing, and is operable to drive rotation of the direction controller about the rotary axis, thereby controlling direction of rotation of the output shaft. The speed controller is operable to vary torque and speed of the output shaft.
    Type: Grant
    Filed: November 16, 2004
    Date of Patent: May 9, 2006
    Inventor: David Kuo
  • Patent number: 6971454
    Abstract: A drill/driver (e.g. an electric drill) with a screwdriver bit attachment, and a method of controlling the drill/driver, are described. This method of control will greatly reduce the occurrence of stripped screw heads on most types of screws. By periodically stopping insertion of a screw and reversing direction of the screwdriver bit, the screwdriver bit will be reinserted fully back into the screw head. By ensuring the screwdriver bit is always fully inserted in the screw head, the stripping of a screw head will be prevented. This can be easily implemented on most types of powered screwdrivers including the most common device used for screw insertion on a construction job site, the cordless drill/driver.
    Type: Grant
    Filed: March 16, 2004
    Date of Patent: December 6, 2005
    Inventor: Edward M. Bogue
  • Patent number: 6854529
    Abstract: Disclosed is an optimizing method for regulating the operating state of a guided machine tool having a tool rotating at a certain speed and subjected to a percussion frequency during a boring action, in which the tool, subjected in addition to a force, is driven into an object of a given material.
    Type: Grant
    Filed: August 30, 2001
    Date of Patent: February 15, 2005
    Assignees: Fraunhofer-Gesellschaft zur Forderung der angenwandten Forschung e.V., Black & Decker
    Inventors: Helge-Björn Kuntze, Christian Frey, Andreas Jacubasch, Reinhard Plietsch
  • Patent number: 6536537
    Abstract: The present invention relates to a powered screw driver having a spindle 20 that is caused to rotate by an electric motor 10 within a range of about 5000 rpm (revolutions per minute) to about 7000 rpm (revolution per minute) when the spindle 20 idles. Because the spindle 20 rotates at a high revolution speed, the screw-fastening operation can more quickly be completed when the user of the screw driver 1 fastens the screw in a normal posture. The screw driver 1 may used to fasten screws having a pitch within a range of about 1.3 mm to 2.0 mm (i.e. about {fraction (1/32)} inch to {fraction (3/32)} inch).
    Type: Grant
    Filed: February 29, 2000
    Date of Patent: March 25, 2003
    Assignee: Makita Corporation
    Inventors: Katsuhiko Sasaki, Kazunori Tsuge, Yukihiko Yamada
  • Patent number: 6484814
    Abstract: An electrical hand operated tool driving device (1) for producing an at least partially impacting movement of a tool (11) with an air striking mechanism (2) and a no-load stroke disconnection, which scans the no-load stroke position (9) by a sensor (14) and evaluates it with an assigned control unit (15), and in the event of a no-load stroke, lowers the rpm of an energizing driving mechanism (3) over the control unit (15) to a previously fixed reduced rpm.
    Type: Grant
    Filed: July 6, 2001
    Date of Patent: November 26, 2002
    Assignee: Hilti Aktiengesellschaft
    Inventor: Hans-Werner Bongers-Ambrosius
  • Patent number: 5839518
    Abstract: A centrifugal force-controlled coupling switch mechanism including a rotary base coupled between a reversible motor shaft of a reversible motor and an output shaft, an eccentric block pivoted to the rotary base and adapted for controlling engagement between the rotary base and the output shaft, a clutch adapted for controlling the engagement between the eccentric block and the output shaft, the clutch including a clutch body having two forward locating pins forced by a spring to disengage the eccentric block from the output shaft, and three smoothly curved actuating plates equiangularly retained to the clutch body by a spring retainer and forced by a centrifugal force to expand and to push the clutch body backwards in disengaging its locating pins from the eccentric block for permitting the eccentric block to be forced into engagement with the fixed coupling block of the output shaft by the centrifugal force when, the rotary base is turned with the clutch body by the reversible motor shaft of the reversible m
    Type: Grant
    Filed: July 16, 1997
    Date of Patent: November 24, 1998
    Inventor: Shibata Setsuko
  • Patent number: 5786812
    Abstract: The invention concerns a tablet pointer that enables the drag mode to be retained even when the operation surface of a tablet sheet is so narrow that the stylus press-held thereto needs to be temporarily lifted off. Switch data generating member provided in the tablet pointer produces switch data indicating the operating state of a mouse switch and device output data of the tablet pointer is fed to a personal computer as an output of an operation unique to the mouse, such as drag mode data. While in a keep-drag mode, the switch data generating member does not cancel the drag mode even if it is supplied with an ordinary drag cancel input. Hence, the drag mode can be retained even if it receives a drag mode cancel signal during the drag operation.
    Type: Grant
    Filed: June 11, 1996
    Date of Patent: July 28, 1998
    Assignee: SMK Corporation
    Inventors: Osamu Yoshikawa, Ryo Okamura, Minekazu Miyazaki, Noriyuki Nakanishi
  • Patent number: 5740892
    Abstract: A torque transmission mechanism to be used in a power wrench includes a body driven by a motor, having a central bore to rotatably support therein a toothed end of an output shaft. The toothed end of the shaft has a pair of diametrically opposite teeth, each defined by two circumferentially opposite contact faces that extend along radii of the output shaft. The body has a radial notch communicating the bore with a coupling member pivotally received therein. The coupling member has two opposite wings alternately movable into the bore with the rotation thereof to selectively engage one of the teeth for driving the shaft. A centrifugal clutch is provided between the body and the motor to control the movement of the wings.
    Type: Grant
    Filed: August 26, 1996
    Date of Patent: April 21, 1998
    Inventor: Chen Shu-Hsia Huang
  • Patent number: 5379851
    Abstract: A power screwdriver disclosed includes a housing, a reversible motor, a screw-driving device, a transmitting shaft, and a handle. The screw-driving device includes a centrifugal clutch, a rotor and an engaging set. The shaft is connected to the motor at one end and to the rotor at the other end so as to transmit rotating power from the motor to the rotor. The screwdriver automatically switch screwing actions in accordance with the rotating speed thereof.
    Type: Grant
    Filed: March 14, 1994
    Date of Patent: January 10, 1995
    Inventor: Chen S. Huang
  • Patent number: 5156221
    Abstract: An electrical hand-held device, such as a screwdriver or the like, includes an output shaft, a drive motor for driving the same, an actuating coupling for connecting the output shaft with the drive motor, a distance sensor for sensing a coupling position, and a speed controller which, in response to a signal generated by the distance sensor, controls operation of the drive motor. The controller causes the drive motor to accelerate to a high speed and maintain this speed during the screwing process when a rearward pressure is applied to the output shaft and the coupling is in its clutching position.
    Type: Grant
    Filed: June 21, 1991
    Date of Patent: October 20, 1992
    Assignee: CEKA Elektrowerkzeuge AG & Co. KG
    Inventor: Armin Breitenmoser
  • Patent number: 5154242
    Abstract: A power tool includes a DC motor for tightening a fastener through three consecutive stages. In the first stage, the motor is rotated at a high speed to tighten the fastener to a pre-seated condition which is acknowledged by the tool. Then, the motor is temporarily stopped and restarted at a low speed for tightening the fastener to its seated condition to complete the second stage. At the third stage, a control is made to gradually increase a field current in a feedback manner by constantly monitoring the field current flowing through the motor up to a predetermined current limit determined as directly related to an intended tightening torque at which the fastener is tightened past the seat condition. After the field current reaches the current limit, the motor is stopped to complete the tightening cycle.
    Type: Grant
    Filed: August 26, 1991
    Date of Patent: October 13, 1992
    Assignee: Matsushita Electric Works, Ltd.
    Inventors: Koji Soshin, Shinichi Okamoto
  • Patent number: RE44311
    Abstract: A control system is provided for use in a power tool. The control system includes: a rotational rate sensor having a resonating mass and a controller electrically connected to the rotational rate sensor. The rotational rate sensor detects lateral displacement of the resonating mass and generates a signal indicative of the detected lateral displacement, such that the lateral displacement is directly proportional to a rotational speed at which the power tool rotates about an axis of the rotary shaft. Based on the generated signal, the controller initiates a protective operation to avoid further undesirable rotation of the power tool. The controller may opt to reduce the torque applied to shaft to a non-zero value that enables the operator to regain control of the tool.
    Type: Grant
    Filed: March 19, 2012
    Date of Patent: June 25, 2013
    Assignee: Black & Decker Inc.
    Inventors: Qiang Zhang, Uday Deshpande, John Charles Vanko, Jason Leh, Craig Schell, Thomas Jay Bodine, Joao Norona, David Beers
  • Patent number: RE44993
    Abstract: A control system is provided for use in a power tool. The control system includes: a rotational rate sensor having a resonating mass and a controller electrically connected to the rotational rate sensor. The rotational rate sensor detects lateral displacement of the resonating mass and generates a signal indicative of the detected lateral displacement, such that the lateral displacement is directly proportional to a rotational speed at which the power tool rotates about an axis of the rotary shaft. Based on the generated signal, the controller initiates a protective operation to avoid further undesirable rotation of the power tool. The controller may opt to reduce the torque applied to shaft to a non-zero value that enables the operator to regain control of the tool.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: July 8, 2014
    Assignee: Black & Decker Inc.
    Inventors: John Charles Vanko, Jason Leh, David Beers
  • Patent number: RE45112
    Abstract: A control system is provided for use in a power tool. The control system includes: a rotational rate sensor having a resonating mass and a controller electrically connected to the rotational rate sensor. The rotational rate sensor detects lateral displacement of the resonating mass and generates a signal indicative of the detected lateral displacement, such that the lateral displacement is directly proportional to a rotational speed at which the power tool rotates about an axis of the rotary shaft. Based on the generated signal, the controller initiates a protective operation to avoid further undesirable rotation of the power tool. The controller may opt to reduce the torque applied to shaft to a non-zero value that enables the operator to regain control of the tool.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: September 9, 2014
    Assignee: Black & Decker Inc.
    Inventors: Qiang Zhang, Uday Deshpande, John Charles Vanko, Jason Leh, Craig Schell, Thomas Jay Bodine, Joao Norona, David Beers