Abstract: An electric tool includes a brushless motor having a plurality of phases, the brushless motor. The brushless motor includes a plurality of stator coils connected in parallel with each of the plurality of phases, and a plurality of crossover wires, each of the crossover wires being configured to electrically connect the plurality of stator coils for each of the plurality of phases to each other. The plurality of crossover wires for the plurality of phases are electrically connected to each other.
Abstract: An impact tool which transmits an impact force to a tool bit supported by a casing includes: a cylinder which is attached to the casing and has an opening on one end side thereof to which the tool bit is inserted; an intermediate element which is provided in an inside of the cylinder so as to be able to move straight, has a projection projecting in a radial direction so as to regulate a range of the straight movement, and transmits the impact force to the tool bit; and passages and which communicate a space in an inside of the cylinder at a position nearer to the tool bit than the projection with the outside of the cylinder and penetrate through the cylinder in the radial direction.
Abstract: In order to provide a charging apparatus for efficiently cooling a battery pack, the charging apparatus comprises: a case 2 having a bottom portion, an upper portion opposite to the bottom portion, and a side portion coupling the bottom portion and the upper portion; a plurality of fans 5 and 6 provided in the case, the plurality of fans being arranged along the side portion; and a charging circuit portion 4 provided in the case and configured to charge a battery pack, the charging circuit having a heat-producing element that produces heat in connection with charging of the battery pack 3.
Abstract: In an air compressor, inner blades of a cooling fan are formed into a centrifugal type, and outer blades are formed into an axial flow type. Exterior air is sucked through a ventilating window by the outer blades, and an air stream (CA1) is generated. A part of the generated air stream flows towards a stator coil, like an air stream (CA2). By a negative pressure generated by the inner blades, the air in the vicinity of the stator coil is sucked to the inner blades, like an air stream (CA3). The sucked air flows out from a motor-side opening towards a non-motor-side opening by a negative pressure generated by the outer blades, is sucked to the outer blades like an air stream (CA4) and flows out together with the air stream (CA1).
Abstract: A centrifuge including: a rotor configured to hold a sample and configured to be detachably mounted, a rotation chamber accommodating the rotor, a plurality of motors configured to be rotationally driven by three-phase AC power, and a control device configured to control centrifuging operation, wherein one of the plurality of motors is a centrifuge motor configured to rotate the rotor, and the control device is configured to change distribution of power supplied to the centrifuge motor and power supplied to another motor of the plurality of motors during one operation.
Abstract: In order to enable easy determination of whether a battery pack possessed by a user is one to be guaranteed or not and clearly differentiate an old battery pack from a new battery pack not to allow the old battery pack to be used in the field, when a battery diagnosis device determines that the battery pack is one to be guaranteed, information held by the diagnosed battery pack is written into a second battery pack different from the diagnosed battery pack.
Abstract: There is provided a driving machine capable of reducing a load applied to a guide member in a direction of a center axis. The driving machine drives a fastener into a workpiece. The driving machine includes a movable piston, a driver blade operating together with the piston and applying driving force to the fastener, a cylinder guiding operation of the piston, a holder provided in a housing and supporting the cylinder, and a vibration damping rubber interposed between the holder and the housing and receiving a load applied to the holder in an operational direction of the piston.
May 13, 2016
May 17, 2018
HITACHI KOKI CO., LTD., HITACHI KOKI CO., LTD.
Abstract: An operator operates a throttle lever and by maximizing the extent of said operation, the drive state is initiated, and the crank shaft rotation rate R increases and reaches the maximal value (RC) thereof. Subsequently, the operator operates the dressing operation lever so as to be in a second state at elapsed time (t0) while keeping the extent of the throttle lever operation maximized. Because a microswitch is turned off, the crank shaft rotation rate (R) is controlled in a range of R1<R<R2. By placing the saw chain in contact with a grindstone fixed to the dressing operation lever simultaneously with said action, dressing work is performed. After the microswitch is turned off at elapsed time (t0), the output of an ignition coil is controlled cyclically by a control unit at a cycle (T1+T2) so as to be on (ignition) during period (T1) and off (flame off) during period (T2).
Abstract: To provide a portable blower having excellent battery heat radiating properties. A battery mounting portion projects convexly into an air passage. Outer surfaces of a bottom surface section and side surface sections of the battery mounting portion form part of an inner surface of the air passage. The battery mounting portion holds a battery pack at an attitude that a center of gravity of the battery pack is as close to a handle portion as possible. Specifically, the battery mounting portion holds the battery pack in such a manner that the greatest surface of the battery pack having a substantially cubic shape faces the handle portion. The battery mounting portion holds the battery pack in such a manner that a longitudinal direction of the battery pack faces the air passage.
Abstract: This invention provides an electrical apparatus that includes a main body portion, a battery pack, and a frame portion. The main body portion comprises a converting portion that may convert electric power to one of light, wind, heat, and sound; and an outputting portion. The battery pack may detachably mounted on a battery holder provided at the main body portion, and may supply electric power to the converting portion. The frame portion may rotatably support the main body portion, and may define a first ground contact plane that can contact a ground surface and a second ground contact plane that can contact the ground surface at a different angle from an angle of the first ground contact plane. The main body portion may be rotatable relative to the frame portion without contacting the ground surface.
Abstract: An electric working machine including: a motor; a control unit configured to control rotation of the motor; a fixed part provided with a handle having a grip portion; a movable part held by the fixed part and is configured to be extendible by sliding relative to the fixed part; and a cutting blade provided to a end portion of the movable pipe and is configured to be driven by the motor; characterized in that the electric working machine further includes a detection unit which is connected to the control unit and is configured to detect whether or not the movable part is positioned at a predetermined extended position relative to the fixed part.
Abstract: A power tool is provided such that noise can be reduced at a wide range of rotation speeds. A speed setting dial to be operated by a worker is disposed on a rear end part of a housing of a grinder. A control part controls driving of a motor by setting the rotation speed of the motor in response to the value of a speed setting signal which indicates a value (voltage) corresponding to an amount of rotation of the speed setting dial by the worker. Although the control part basically causes the rotation speed of the motor to change continuously in response to the rotation amount of the speed setting dial, the control part sets the rotation speed of the motor while avoiding a predetermined rotation speed region in which the noise level is increased due to mechanical and acoustic resonances.
Abstract: An electronic pulse driver includes a motor, a hammer, an anvil, an end tool mounting unit, a power supply unit, and a control unit. The hammer is rotatable together with the anvil. The end tool mounting unit transmits the rotation of the anvil to an end tool. The power supply unit supplies a drive electric power to the motor. The control unit controls the power supply unit to halt a supply of the drive electric power to the motor when an electric current flowing to the motor increases to a prescribed value. The control unit controls the power supply unit to supply to the motor a prestart electric power lower than the drive electric power before supplying the drive electric power in order to permit the power supply unit to supply the drive electric power after the hammer is in contact with the anvil.
Abstract: A miter saw includes a base portion having a mount surface, a cutting unit supporting a saw blade, a support portion, a relative displacement smoothening member, and a sealing structure. The support portion is supported to the base portion for supporting the cutting unit. The support portion includes a rod extending in a sliding direction in parallel to the mount surface and perpendicular to a rotation axis of the saw blade, and a slide-support portion through which the rod slidably extends. The smoothening member is provided between the slide-support portion and the rod. The sealing structure is provided between the slide-support portion and the rod and includes a first seal member provided at one end of the smoothening member, a second seal member provided at an another end of the smoothening member, and a third seal member positioned opposite to the smoothening member with respect to the first seal member.
Abstract: Provided is an electric tool in which the risk of short-circuiting between conductive members of multiple installed switching elements has been reduced by providing partitioning plates between the switching elements. An electric tool, which has a motor, an inverter circuit with multiple switching elements for performing switching operations and controlling the driving of the motor, a control unit for controlling switching element on-off operations, and a circuit board on which the switching elements are loaded, is configured so that the circuit board is housed inside a container-shaped case (40) and the circuit board is secured with a partitioning member (50) that is interposed between the multiple switching elements and has partitioning plates (51, 52a, 52b) obtained from an insulating material.
Abstract: A technique capable of immediately reporting to an operator an occurrence of abnormality in an electric tool is provided. A communication terminal 100 includes a communication-terminal-side control unit that determines whether abnormality has occurred in any of electric tools 10, 200, 300, and 400 based on information acquired from the electric tools 10, 200, 300, and 400 via wireless communication. When the communication-terminal-side control unit determines the occurrence of abnormality in any one of the electric tools 10, 200, 300, and 400, the occurrence of abnormality in the electric tool 10, 200, 300, or 400 is reported by at least one of a report unit included in the electric tools 10, 200, 300, and 400 other than the electric tool 10, 200, 300, or 400 in which the occurrence of abnormality is determined and a report unit included in the communication terminal 100.
January 9, 2015
Date of Patent:
April 10, 2018
HITACHI KOKI CO., LTD.
Tomomasa Nishikawa, Takuya Konnai, Tatsuya Ito
Abstract: A battery charger that is configured to charge a battery pack including a secondary battery includes: a housing; and a charging circuit unit disposed in the housing. The housing defines a first air passage in which air flows to cool the secondary battery and a second air passage in which air flows to cool the charging circuit unit. The second air passage is independent from the first air passage.
Abstract: The present invention reduces or shuts off output electric power of a battery pack, which is connected to an electric device, depending on an abnormality. According to the present invention, a battery pack is detachably connected to an electric-device main body having a switch, and includes a first electric-power control circuit that outputs a first signal to the electric-device main body when the switch is operated, the first signal for allowing supply of electric power to the electric-device main body, a second switching element provided on an electric-power supply path that supplies electric power to the electric-device main body, and a second electric-power control circuit that outputs a second signal to the second switching element if an abnormality occurs in the battery pack, the second signal for reducing or shutting off the electric power supplied to the electric-device main body.