Abstract: A rotary impact tool includes: a hammer rotating by receiving a rotational force of a motor; an anvil rotating by receiving a rotational force of the hammer; and an end tool attached to the anvil, the rotary impact tool being constructed such that when a torque of a value not less than a predetermined value is applied to the anvil from the outside, the hammer is disengaged from the anvil to rotate idle and applies an impact to the anvil in a rotational direction after rotating idle by a predetermined angle, the rotary impact tool including an impact detection means detecting impacts and a speed switching means switching the rotational speed of the motor, and when the impact detection means detects an impact during rotation of the anvil in a tightening direction, the speed switching means switches the rotational speed of the motor from a normal speed to a low speed.

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.

Abstract: A power tool including a motor for rotatably driving a tool bit at an attained rotational speed, a source for supplying an electric current to the motor, a sensor for measuring the current, and a control device. The control component fulfils the task of detecting a variation of the slope of the current in the course of time, and generates a control signal. The rotational speed of the tool is reduced in response to the control signal. The power tool automatically detects whether the work piece operated by the tool bit reaches a predetermined position by electronic control means. It may make sure that the screw is driven into a piece of wood and does not go beyond the predetermined position once it detects that the work piece reaches the position and carries out a changing action.

Abstract: An impact tool (100) includes a spindle (11), a motor (1), a rotational impact system (10), a current detecting unit (32), and a current control unit (31). The spindle extends in an axial direction thereof. The motor provides the spindle with a rotational power in accordance with a motor current flowing therethrough. The rotational power rotates the spindle about the axis at an rpm value. The rotational impact system provides the spindle with an impact force in the axial direction, thereby transmitting both the rotational power and the impact force to an end bit. The current detecting unit detects a current value of the motor current. The current control unit reduces the current value if the current value detected by the current detecting unit exceeds a predetermined value.

Abstract: An air driver device having a simple construction, being of a compact size, and having excellent durability. The air driver device is designed to shut off a supply of compressed air to an air motor, by means of a tightening torque control mechanism and a shut-off valve mechanism, in a case where the tightening torque reaches the set torque value. The air device is designed to tighten screw members at a prescribed tightening force, wherein the tightening torque control mechanism is composed of (i) a clutch unit, (ii) a driving piston on the back face of which is formed one clutch plate, so that clutch plates of the clutch unit may move by making rotational differential motions in a case where the tightening torque reaches the set torque value, (iii) a cylinder for storing this driving piston, (iv) a check valve for operating the shut-off valve mechanism, in linkage with the driving piston through an oil charged in the cylinder, and (v) a torque control member for regulating the set torque value.

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.

Abstract: A system, and a method of using a system, for controlled tool operation. The method includes providing a tool used in a force application such as a such torque application. The tool communicates with a controller which can communicate with the tool, and to a display in communication with the tool and the controller. The controller can be programmed with operational information about a tool operation. Information related to the operational information is displayed to a user during use. Service information including at least information about an amount of force applied during use is recorded and stored in the controller. Also disclosed is a computerized system for controlled tool operation which sends operational instructions to the tool before use and retrieves service information from the tool after use.

Abstract: A motor control apparatus that can calculate a proper amount of cogging torque compensation even in cases where components due to other factors than cogging torque (for example, components due to gravitational torque, etc.) are superimposed on a torque command being output during constant slow-speed feed operation.

Abstract: A clamping device for machine tools is provided with a chuck, the clamping jaws of which are actuated by a draw rod, the clamping device having of a servomotor, a movement converter and a force accumulator, the servomotor is connectable to the movement converter for triggering clamping movements. The movement converter and the force accumulator are disposed in a housing connectable to the machine spindle, and in clamping position of the clamping device, the sliding sleeve can be decoupled from the servomotor, and the housing can be connected to the movement converter by means of the sliding sleeve. The servomotor is operated only to clamp and unclamp a workpiece, and is in a driving connection with the clamping device in operating conditions. All components of the clamping device involved in power transmission are in driving connection with the machine spindle during the machining of the workpiece.

Abstract: A technique is provided which improves durability in a power tool having a torque transmission device. The representative power tool has a torque transmission device 151. The torque transmission device 151 includes a projection 171 formed on one of opposed surfaces of a first rotating member 153 and a second rotating member 155 and protruding in a direction of a rotational axis, a recess 161 for receiving the projection 171, which is formed in the other of the opposed surfaces and recessed in the direction of the rotational axis, a projection-side engagement surface 175a formed on the projection 171, and a recess-side engagement surface 165a formed on the recess 171. Torque is transmitted when the projection-side and recess-side engagement surfaces 175a, 165a are engaged with each other, while the torque transmission is interrupted when the projection-side and recess-side engagement surfaces 175a, 165a are disengaged from each other.

Abstract: Disclosed is a method for screwing in and tightening a screw connection (1) to a predetermined tightened level (2), especially a predetermined torque level (2) or a predetermined pretension level, with the aid of a hand-held screwing tool (3) comprising a regulated drive unit (4) and/or control functionality, particularly an electric nut runner (3). A tightening phase (B-C-D), during which the screw head rests against the supporting surface (6) of the screw connection (1), starts following a screwing phase (A). In order to improve said method, the speed (N) of the screwing tool (3) is increased to an output speed (7) for the tightening phase (B-C-D) within an acceleration time (8) in the tightening phase (B-C-D) and is lowered within a delay time (9) prior to or until reaching the predetermined tightened level (2).

Abstract: An electrical power tool includes a housing, an electrical motor, an end-bit holding section, a transmitting mechanism, a cap, and a lighting section. The housing has one end. The electrical motor is accommodated in the housing and is configured to generate a rotational driving force. The end-bit holding section is provided at the one end and is rotatable about a rotational axis. The transmitting mechanism transmits the rotational driving force to the end-bit holding section. The cap is attached to the one end. The lighting section allows an entirety of the cap to be luminous.

Abstract: A power tool includes an output shaft configured to rotate about a longitudinal axis, a motor drivably connected to the output shaft to impart rotary motions thereto, and a rotational motion sensor spatially separated from the output shaft and operable to determine the user-imparted rotational motion of the power tool with respect to the longitudinal axis. A controller is electrically connected to the rotational motion sensor and the motor. The controller determines angular velocity of the power tool about the axis, rotational displacement of the power tool about the axis, and/or a direction of the rotational displacement using input from the rotational motion sensor. The controller then controls the motor according to the angular velocity, the rotational displacement, and/or the direction of the rotational displacement.

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.

Abstract: An electrical power tool may include a speed change device that is capable of being automatically changed as an external torque applied to a spindle is increased. In a high speed low torque mode before an automatic speed change, an extremely high output rotation speed in which an output torque sufficient to progress the screw tightening operation to the end cannot be generated is set. The output rotation speed before the speed changing operation is set in a range of about 4.5 times to 6.0 times the output rotation speed after the speed changing operation. Thus, in an initial stage of the screw tightening operation, it is possible to quickly performing the operation with a high speed rotation than ever before. Conversely, after the automatic speed change, it is possible to complete the screw tightening operation with the large output torque.

Abstract: The invention relates to a safety device for portable tool with a heat engine that is capable of stopping, almost instantly, the operation of said tool after unexpected, sudden, and violent movements, said device including at least one electronic accelerometer enabling the measurement of the acceleration along at least one plane or axis (X, Y, Z), the output(s) of said accelerometer being connected to an electric and/or electronic monitoring means, wherein said electric and/or electronic monitoring means consists of an electric and/or electronic management card, the latter and the accelerometer being supplied with electric voltage by an electric current generator known per se and actuated by the heat engine, said electric and/or electronic management card being configured to process analog or digital electrical data from the accelerometer and activate a means ensuring that said heat engine stops almost instantly.

Abstract: While a load torque applied to a tool shaft is lower than a predetermined value, a moving member is maintained at a first position, and a sun gear is rotated integrally with an internal gear. When the load torque applied to the tool shaft reaches or exceeds the predetermined value, the moving member is moved to a second position, to thereby prohibit relative rotation of the internal gear and a gear case. A latch member is engaged in a catching portion of the moving member when the moving member is moved to the second position, to thereby prevent the moving member from moving back to the first position. In this manner, repetitive switching between speed reduction ratios can be prevented even when the load torque applied to the tool shaft fluctuates.

Abstract: The invention relates to a discontinuous clamping wrench, of the type comprising a motor and a pulse clutch integrated in a casing, characterised in that it comprises measurement means of dynamic phenomena induced by said clamping on said casing, with a view to correlating said measurement with a clamping level.

Abstract: An electrical power tool may include an electric motor, a speed change device, and a battery pack. The speed change device is capable of changing a reduction ratio thereof and capable of automatically switching between a high speed low torque mode in which a high speed low torque is output and a low speed high torque mode in which a low speed high torque is output, based on an external torque applied to a spindle. A distance from the axis to a center of gravity of the battery pack and a mass of the battery pack are set such that an inertia moment around the axis is greater than a reaction around the axis that is produced when the high speed low torque mode is changed to the low speed high torque mode in the speed change device.

Abstract: An improved method is provided for controlling a power tool having a rotary shaft. The method includes: disposing an inertial mass in a housing of the power tool, such that the inertial mass is freely rotatable about an axis of rotation which is axially aligned with the rotary shaft; monitoring rotational motion of the power tool in relation to the inertial mass during operation of the power tool; and activating a protective operation based on the rotational motion of the power tool in relation to the inertial mass.

Abstract: A power tool including a motor, an output member and a transmission disposed between the motor and the output member. The transmission includes a ring gear with opposite axial end faces. The power tool also includes a clutch for limiting an output of the transmission. The clutch includes an annular clutch face disposed about the ring gear. At least a portion of a side of the ring gear is configured such that an included angle between the annular clutch face and the at least a portion of the side of the ring gear is about ninety five degrees to about one hundred fifty degrees.

Abstract: An electric power tool includes a motor, a reduction mechanism, a driving unit, a bearing unit, a housing, a speed changing unit, a power switch, and an operation detecting unit which detects a reduction ratio changing operation performed by the speed changing unit to control electric power supplied to the motor. The reduction mechanism transfers the rotating power of the motor, and the driving unit transfers the rotating power of the reduction mechanism to a tip end tool. The bearing unit rotatably supports the driving unit, and the housing accommodates the motor, the reduction mechanism, the driving unit and the bearing unit. The speed changing unit changes a reduction ratio of the reduction mechanism, a power switch for turning on and off a power source of the motor.

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 power tool comprises a signal generator and a control system electrically coupled to the signal generator and operatively engaged with the gear transmission mechanism such that when the signal generator is manually activated, an electric signal is generated and transmitted to the control system to cause the gear transmission mechanism to vary the gear reduction ratio.

Abstract: A motor control apparatus that can calculate a proper amount of cogging torque compensation even in cases where components due to other factors than cogging torque (for example, components due to gravitational torque, etc.) are superimposed on a torque command being output during constant slow-speed feed operation.

Abstract: A hand-guided power tool according to the invention, has a torque coupling, and a planetary gear disposed in a gearbox for transmitting a torque, generated by a drive motor, to a drive shaft. The planetary gear has at least one ring gear, axially displaceable in the gearbox, for releasing the torque coupling.

Abstract: A discontinuous drive power tool assembly for generating rotational torque includes a spindle having a first end portion and a second end portion. The first end portion of the spindle is configured to engage and rotate an object. The tool assembly also includes a pulse hammer selectively engagable with the second end portion of the spindle, and a motor that includes a motor shaft engagable with the pulse hammer. The motor is configured to rotate the pulse hammer. The tool assembly also includes a rotational position sensor disposed adjacent the motor. The rotational position sensor is configured to measure the rotational position of a second portion of the motor shaft which is opposite the first end portion of the motor shaft during operation of the tool assembly.

Abstract: A system, and a method of using a system, for controlled tool operation. The method includes providing a tool used in a force application such as a such torque application. The tool communicates with a controller which can communicate with the tool, and to a display in communication with the tool and the controller. The controller can be programmed with operational information about a tool operation. Information related to the operational information is displayed to a user during use. Service information including at least information about an amount of force applied during use is recorded and stored in the controller. Also disclosed is a computerized system for controlled tool operation which sends operational instructions to the tool before use and retrieves service information from the tool after use.

Abstract: This invention relates to a power tool one having a driven member 5 for releasably gripping a working element 4. The power tool is operable in a working mode in which the working element performs work, or an adjustment mode in which the driven member 5 grips or releases the working element 4. The power tool includes a powered selector means including a controller 6 which enables the operator to select the mode of operation of the power tool.

Abstract: An improved method is provided for controlling a power tool having a rotary shaft. The method includes: disposing an inertial mass in a housing of the power tool, such that the inertial mass is freely rotatable about an axis of rotation which is axially aligned with the rotary shaft; monitoring rotational motion of the power tool in relation to the inertial mass during operation of the power tool; and activating a protective operation based on the rotational motion of the power tool in relation to the inertial mass.

Abstract: The torque control circuit of a hand tool contains a motor driving circuit, a current detection circuit, a reference voltage generation circuit, a current limiting circuit, and a torque configuration circuit. In the last stage of operation of the hand tool and when the average current has reached a predetermined level, the average current is maintained for a period of time to provide a constant average power and therefore to achieve an appropriate tightness of the bolt or nut being operated. The detection and control of current is achieved by a linear circuit which is robust to the heavy noises produced by the motor. A microprocessor is adopted to consider factors such as temperature in determining a suitable current level.

Abstract: A ratchet wrench has a handle, a transmitting device, a torque adjusting device and a ratchet head. The transmitting device is connected to the handle and has a barrel, a transmitting seat and a transmitting shaft. The barrel is connected to the handle and has two threaded segments and multiple elongated holes. The transmitting shaft is rotatably mounted in the barrel and has a driving disk and an eccentric rod. The torque adjusting device is connected to the transmitting device and has a casing, a limiting assembly and a spring. The casing is connected to the barrel. The limiting assembly is mounted around the transmitting shaft and has two pressing rings and a push bearing. The spring is mounted around the transmitting shaft and presses against the pressing rings to push the holding pins abutting with the holding recess. The ratchet head is connected to the transmitting device.

Abstract: An overspeed protection subsystem is provided for a power tool having an electric motor. The overspeed protection subsystem is comprised of: a motor switch coupled in series with the motor; a motor control module interfaced with the motor switch to control switching operation of the motor switch; and an overspeed detection module that determines rotational speed of the motor and disables the power tool when the rotational speed of the motor exceeds a threshold.

Abstract: The present invention has disclosed a variable speed tool and a variable speed control method. The tool includes a switch; a gearbox housing; a motor; an outputting shaft; a multistage transmitting gear train and a gearshift ring which are mated with the motor and the outputting shaft, the gearshift ring having inner teeth; a gearshift fork mated with the gearshift ring; a tension spring arranged between the gearbox housing and the gearshift fork; and a torque sensing ring provided with a sliding groove in which the gearshift fork is movably disposed. When the load of the outputting shaft has reached to a predetermined value, the torque sensing ring makes the gearshift fork move axially in the sliding groove under the action of the tension spring, thus bringing the gearshift ring to move axially. The variable speed tool of the present invention may automatically adjust the rotating speed and the torque of the outputting shaft according to a variation of the load torque.

Abstract: A clutch arrangement for use in a power tool having a multi-speed transmission assembly. The clutch arrangement includes a clutch member and a follower. The clutch member is coupled to a member of the transmission assembly that is proximate the torsional input of the transmission assembly and which must be in a non-rotating position to permit the transmission assembly to perform a torque multiplication operation. The follower is biased into engagement with the clutch member to inhibit relative rotation therebetween to permit the transmission assembly to perform a torque multiplication operation. When, however, the torsion that is exerted onto the clutch member is sufficient to overcome the frictional engagement between the follower and clutch members, the clutch member, and the transmission member, rotate, thereby inhibiting the capability of the transmission to continue to perform the torque multiplication operation.

Abstract: A torque overload clutch for an electrical power tool, such as a percussion hammer drill, is provided. The clutch is accommodated in a cavity in a gear cog. Spring washers are used to urge ball bearings into indentations formed in the base of the cavity. The ball bearings are accommodated in cavities formed in a drive plate which engages with the spindle drive of the power tool. The spring washers are held in position by a circlip or a threaded plate. The threaded plate arrangement provides means for compressing the spring washers with a consistent force across a manufactured batch. A method of manufacturing the clutch is also disclosed.

Abstract: A transmission assembly for a power tool comprises a first transmission path comprising a high speed transmission path and a second transmission path comprising a low speed transmission path. Driven gears of each transmission path are permanently driven during operation of the transmission. A controller is provided for engaging or disengaging the high speed transmission path in response to monitored operating current of an electric motor providing a driving torque to an input of the transmission. When disengaged, a driven gear of the high speed transmission path continues to be driven, but the driven gear is disengaged from an output of the transmission. Consequently, under these circumstances, the low speed transmission path is the ‘active’ transmission path providing a low speed, high torque drive to the transmission output.

Abstract: A power tool includes 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 power tool includes a signal generator and a control system electrically coupled to the signal generator and operatively engaged with the gear transmission mechanism such that when the signal generator is manually activated, an electric signal is generated and transmitted to the control system to cause the gear transmission mechanism to vary the gear reduction ratio.

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.

Abstract: The invention relates to a damping device for an output shaft (26) in a gearbox (14, 16), where the gearbox (14, 16) is arranged for rotation of a rotational degree of freedom (Z4,Z5) in a rock-drilling rig (2), and thus for positioning of the same, and where the damping device (18) comprises a brake (38) that acts on the output shaft (26) of the gearbox (14, 16), which brake (38) acts as an oscillation damper for the movement of the output shaft (26), whereby a gearbox (14, 16) with play can be used for applications that require a high degree of precision such as positioning, e.g. measuring a position for a drill hole. The invention also relates to a gearbox (14, 16) and a rock-drilling rig (2) with damping device (18), respectively.

Abstract: A method of operating a hand power tool in one embodiment includes generating a variable speed control signal with a solid state switch that corresponds to a selected speed for a motor, generating a pulse width modulated (PWM) signal corresponding to the variable speed control signal, generating H-bridge driving signals for an H-bridge circuit in correspondence with the PWM signal, and selectively coupling a motor to a power source using the H-bridge circuit in accordance with the H-bridge driving signals.

Abstract: Reaction adaptors for torque power tools pneumatically, electrically, hydraulically and manually driven, tools having the adaptors, and methods of using the same, are disclosed. In one illustrative example, a reaction adaptor includes a first force-transmitting element, when engaged with a tool, being rotatable about a turning force axis of the tool; and a second force-transmitting element, when engaged with the first element, being one of rotatable about, extensible and retractable along, and rotatable about and extensible and retractable along at least a distal portion of the first element. In another illustrative example, a tool for tightening or loosening a fastener includes the reaction adaptor. A method of using the tool having the reaction adaptor includes the acts of providing the tool; and providing the reaction adaptor.

Abstract: A power tool may include an electronically commutated motor such as, for example, a brushless DC permanent magnet motor with a rotor having internally mounted magnets and/or cavities filled with air or other non-magnetic materials. A control system may be used to control the motor in a manner that implements field weakening when the speed of the motor increases beyond its rated motor speed, or when the torque demands on the motor continue to increase after the maximum power output of the motor is reached. The field weakening may offset the growing back EMF and may enable a constant power and constant efficiency to be achieved by the motor over a wide speed range, rather than at just a single predetermined operating speed. Pulse width modulation control of the motor may be used up until the motor reaches its maximum power output.

Abstract: A control method according for an impact wrench includes ascertaining whether the impact wrench applies an impact when the drive shaft rotates in a lower speed range. The speed of the drive shaft then is increased to a higher speed range as a function of an ascertained impact during the rotation in the lower speed range.

Abstract: A power tool includes an output member (8) projecting from the tool housing (4), a drive (6) located in the housing for rotating the output member (8), and a slip clutch (22) for transmitting torque from the drive (6) to the output member (8) and including a plurality of clutch elements (24) retained against rotation relative to the housing (4), a plurality of separate spring elements (28) for adjustable preloading the clutch elements (24) against the counter-clutch elements (51) of the control element (18) for retaining the control element (18) against rotation upon application of the torque thereto until threshold of the torque is reached, and a common support element for supporting the spring elements and movable relative to the housing (4).

Abstract: A torque adjusting structure for power tools includes an accommodating device and a torque device. The accommodating device has a head part and a body part. The head part is formed with a groove for the connection of a power tool. The bottom of the groove is provided with a power base on which power connecting points for electrical connection of the power tool are provided. It provides the required electrical power for the power tool to start. The torque device has an acting part and an adjusting part. The torque device connects to the body part of the accommodating device using one end of the acting part. The other end of the acting part connects to the adjusting part.

Abstract: A torque adjusting structure for an air tool includes an accommodating device and a torque device. The accommodating device has a head part and a body part. The head part is formed with a hollow groove. The bottom of the groove is provided with abase on which a connecting element is provided for the nozzle of the air tool to connect. The base is formed with an air inlet connecting the connecting element and the external space. The torque device has an acting part and an adjusting part. The torque device connects to the body part of the accommodating device rising one end of its acting part. The other end of the acting part connects to the adjusting part.

Abstract: In an electric power tool and a method for operating an electric power tool, a torque limitation of an electric motor reacts when a load moment exceeds a predetermined threshold and in which an output request is carried out by means of a switch. A supply of current to the motor is interrupted when a criterion for the reaction of the torque limitation is detected based on a speed detection of the motor.

Abstract: A regulator for a power tool for tightening a fastener in order to unite two or more pieces into a joint. The regulator regulates the power tool when tightening the fastener such that the fastener is tightened to a predetermined target. The regulator calculates an output signal to the power tool, which output signal is based on the product of the torque exerted by the power tool on the fastener and the angle for turning the fastener about its axis. The output signal is used for tightening the fastener to the predetermined target. The regulator is also applicable to a power tool for a rivet joint.

Abstract: A handheld tool includes a first power source, a second power source having a characteristic different from a characteristic of the first power source, and an operation part which is operated by a power from at least one of the first power source and the second power source to fasten a fastener.

Abstract: An object is to improve accuracy of tightening torque and to shorten time necessary for fastening a screw in an impact type screw fastening device that uses an electric motor as a rotation driving source. A control method for the impact type screw fastening device that uses an electric motor as a rotation driving source includes the steps of driving the motor to rotate by supplying current to the motor intermittently so that torque exerted on a load by rotation of the motor becomes like pulses on the time axis, and controlling the current of every time of each pulse so that an increment of every time of each pulse of the torque after the torque reaches a target approach torque TQN that is a first set value becomes smaller than that before it reaches the target approach torque TQN.