US Pat. No. 10,205,198

POWER TOOL AND BATTERY PACK

Koki Holdings Co., Ltd., ...

1. A power tool system comprising:a battery pack including at least one secondary battery cell; and
a power tool being capable of continuously performing a desired operation by virtue of discharge current supplied from the secondary battery cell,
wherein in a state where the power tool is driven and the discharge current shows a behavior to once increase and then decrease, the power tool is configured to halt the desired operation when the discharge current having a current value greater than or equal to a predetermined value continues to flow for a predetermined period of time, and
wherein when comparing a first case where the power tool is operated in a first state that the battery temperature of the secondary battery cell is at a first temperature and the power tool is driven with a first discharge current having a value greater than or equal to the predetermined value, with a second case where the power tool is operated in a second state that the battery temperature of the secondary battery cell is at a second temperature higher than the first temperature and the power tool is driven with the first discharge current, the predetermined continuous period of time is longer in the first state than in the second state.

US Pat. No. 10,183,384

POWER TOOL

KOKI HOLDINGS CO., LTD., ...

1. A power tool comprising:a motor configured to be driven by PWM controlling a semiconductor switching element;
a trigger configured to adjust startup and rotation of the motor;
an impact mechanism configured to strike or rotate an anvil by a hammer that is rotated by the motor;
a control device configured to control rotation of the motor,
wherein the power tool has a plurality of operation modes having different fastening torques,
wherein the power tool is configured to perform control at the same duty ratio, irrespective of the operation modes, in a control zone of a high duty ratio, and
wherein the power tool is configured to perform control at a duty ratio set depending on each of the operation modes, in a control zone of a low duty ratio; and
a current detection device configured to detect a current value flowing through the motor or a semiconductor switching element,
wherein when a current value, which is detected by the current detection device when the power tool is driven at the high duty ratio, exceeds a first threshold I1, the control device switches the duty ratio from the high duty ratio to the low duty ratio, and
wherein when a plurality of striking is continuously performed by the impact mechanism, the motor is driven at a state where a duty ratio is changed from a high value to a low value.

US Pat. No. 10,232,498

DRIVING MACHINE

Koki Holdings Co., Ltd., ...

1. A driving machine for driving a fastener, which comprises a head part formed on an end of a shaft part and having a larger diameter than the shaft part, into an object to be fixed, the driving machine comprising:a nose part forming an upper portion of an ejection passage through which the fastener passes;
a contact part being slidable along the nose part and forming a lower portion of the ejection passage;
a driver blade striking the head part of the fastener supplied to the ejection passage; and
a guide part disposed in a lower portion of the nose part and guiding the fastener passing through the ejection passage,
wherein the guide part comprises a curved surface serving as a guide surface that inclines to protrude from a radial outer side toward a radial inner side of the ejection passage, and
wherein a housing groove is formed in the contact part and the guide part enters the housing groove when the contact part slides along the nose part, and
wherein a lower end of the guide surface is disposed outside an edge of the ejection passage.

US Pat. No. 10,173,311

ELECTRIC TOOL

KOKI HOLDINGS CO., LTD., ...

1. An electric tool, comprising:a motor, having a rotor capable of rotating with respect to the stator and a stator having a coil;
a casing, accommodating the motor and having a ventilating window;
a controller, controlling power supply to the coil; and
a cooling fan, sucking an air through the ventilating window and generating a cooling wind in the casing to cool off the motor,
wherein a magnetic body for rotational position detection is disposed to a rotation shaft capable of integrally rotating with the rotor,
a magnetic detection unit detecting a rotational position of the magnetic body is disposed to output a position signal to the controller,
the magnetic body is disposed to be isolated from a wind path of the cooling wind generated by rotation of the cooling fan, and
the controller and the magnetic detection unit are disposed in a housing defining an isolated area not exposed to the cooling wind, and the housing is disposed by extending to a proximity of the magnetic body.

US Pat. No. 10,171,011

ELECTRIC TOOL

KOKI HOLDINGS CO., LTD., ...

1. An electric tool comprising:a motor configured to be driven by PWM controlling a semiconductor switching element;
a trigger configured to adjust startup and rotation of the motor;
a changeover switch configured to switch a rotation direction of the motor between a forward rotation and a reverse rotation;
a power transmission mechanism configured to rotate a tip tool by the motor; and
a controller configured to control rotation of the motor,
wherein in a state where the reverse rotation is set by the changeover switch,
the controller controls a duty ratio of the PWM control of the semiconductor switching element according to an operating amount of the trigger to drive the motor in a case that the operating amount of the trigger is less than a predetermined amount, and
the controller controls the semiconductor switching element at a high duty ratio to drive the motor in a case that the operating amount of the trigger is the predetermined amount or larger, and thereafter the controller restricts the duty ratio of the PWM control of the semiconductor switching element when the controller detects a predetermined state.

US Pat. No. 10,201,865

PORTABLE ELECTRIC CUTTER

Koki Holdings Co., Ltd., ...

1. A portable electric cutter comprising:a brushless motor having a rotator which rotates around a rotation axis;
a housing in which the brushless motor is accommodated;
a handle coupled to the housing, the handle extending in a direction orthogonal to a direction of the rotation axis;
a circular saw blade driven to rotate by the brushless motor;
a base coupled to the housing, having a bottom surface, and having an opening for the circular saw blade;
a fan driven to rotate by the brushless motor and generate an air flow in the housing;
a driving circuit including switching elements for switching power supplied to the brushless motor;
a control circuit for controlling the driving circuit;
a first circuit board on which the driving circuit is mounted; and
a second circuit board on which the control circuit is mounted;
a motor casing that accommodates the brushless motor;
a motor cooling air vent provided at a sidewall part of the motor casing, the motor cooling air vent opening in the direction of the rotation axis of the brushless motor;
a circuit board casing disposed under the handle, the circuit board casing accommodating at least one of the first circuit board and the second circuit board; and
a circuit cooling air vent provided at a sidewall part of the circuit board casing, the circuit cooling air vent opening in the direction of the rotation axis, wherein
the switching elements are cooled by the air flow,
in a cutting direction of the portable electric cutter, the first circuit board and the second circuit board are disposed on a rear side of the brushless motor,
at least a part of either one of the first circuit board and the second circuit board is disposed under the handle so as to overlap the handle when viewed from above the portable electric cutter and to be disposed in a circuit cooling air path that connects the circuit cooling vent and the fan, and
at least a part of the brushless motor is disposed in a motor cooling air path that connects the motor cooling vent and the fan.

US Pat. No. 10,195,728

FASTENER DRIVING TOOL

Koki Holdings Co., Ltd., ...

1. A fastener driving tool, comprising:an operating member that moves along an axis and strikes a fastener;
a weight that moves along the axis; and
an elastic mechanism that is in contact with the operating member and the weight, a first end of the elastic mechanism being in contact with the operating member, a second end of the elastic mechanism being in contact with the weight,
wherein when the operating member moves in a first direction along the axis and the weight moves in a second direction, the elastic mechanism is compressed,
when the elastic mechanism decompresses, the elastic mechanism generates a repulsive force that moves the operating member in the second direction and the weight in the first direction, and
when the operating member moves in the second direction by the repulsive force, the operating member strikes the fastener.

US Pat. No. 10,252,279

CENTRIFUGE HAVING LIGHT EMITTING PART

KOKI HOLDINGS CO., LTD., ...

1. A centrifuge comprising:a rotor;
a rotor chamber accommodating therein the rotor and having an opening;
a motor configured to rotate the rotor;
a door configured to close the opening of the rotor chamber;
an input/output unit configured to receive an input of an operating condition and to display an operating status; and
a housing inlcuding the rotor, the rotor chamber, the motor, the door and the input/output unit,
wherein the housing has the opening at an upper surface thereof,
wherein a light emitting part having a horizontal width longer than the opening is provided in the vicinity of a corner portion at which the upper surface and a front surface of the housing intersect with each other or in the vicinity of a front side of the opening, and
wherein a light emitting form of the light emitting part is configured to be changed depending on the operating status of the centrifuge,
wherein a combination of an emission color, a brightness and a light emitting pattern of LEDs is allotted in correspondence to an operation of the centrifuge, and
wherein a light emitting form indicating at least one operating status of stop, acceleration, running at set speed and deceleration of the rotor is configured to be different from a light emitting form indicating abnormality in the centrifuge.

US Pat. No. 10,199,844

POWER-SUPPLYING DEVICE

Koki Holdings Co., Ltd., ...

1. A power-supplying device comprising:a terminal having a plus side and a minus side, configured to be connected to an external device;
a rechargeable battery configured to output electrical power to the external device via the terminal;
a first shutdown circuit positioned at a plus side of the rechargeable battery, the first shutdown circuit being configured to interrupt electricity over a first path between the rechargeable battery and the plus side of the terminal;
a second shutdown circuit positioned at a minus side of the rechargeable battery, the second shutdown circuit being configured to interrupt electricity over a second path between shutdown output of the rechargeable battery and the minus side of the terminal;
a controller configured to control the first shutdown circuit and the second shutdown circuit;
a step-down circuit configured to apply a prescribed voltage to the controller, the stepdown circuit configured to be connected to an external charging device through a third path; and
a first switching circuit, wherein the step-down circuit is further configured to be connected to the rechargeable battery via the first switching circuit, and the controller is configured to control the first switching circuit to turn on and off electrical connection between the rechargeable battery and the step-down circuit, wherein the step-down circuit receives power supply from one of the external charging device and the rechargeable battery when the first shutdown circuit interrupts electricity over the first path.

US Pat. No. 10,307,841

POWER TOOL

Koki Holdings Co., Ltd., ...

1. A power tool comprising:a brushless motor;
a rectifier circuit configured to rectify an AC voltage and output a rectified voltage;
a smoothing circuit configured to smooth the rectified voltage and output a smoothed voltage;
an inverter circuit configured to supply the smoothed voltage to the brushless motor while performing switching actions with respect to the smoothed voltage;
a controller configured to control switching operations of the inverter circuit;
an operating part being operable by a user; and
a switch rendered ON in accordance with an operation performed in the operating part by the user to allow power to be supplied to the inverter circuit by the rectifier circuit through the smoothing circuit and rendered OFF in accordance with release of the operation by the user to interrupt the inverter circuit from the rectifier circuit to halt supplying the power to the inverter circuit,
wherein the smoothing circuit comprises a first capacitor and a second capacitor connected in parallel,
wherein the switch is interposed between the rectifier circuit and the inverter circuit and is interposed between the first capacitor and the inverter circuit, and
wherein the controller is configured to control the switching operations of the inverter circuit to drive the brushless motor in accordance with a signal inputted in accordance with the operation performed in the operating part by the user.

US Pat. No. 10,344,951

ILLUMINATING DEVICE

Koki Holdings Co., Ltd., ...

1. A portable illuminating device comprising:a battery as a power source;
a handle adapted to be held by a hand of an operator;
a base attached to one end of the handle and movable as a whole with respect to the handle;
a first lamp integrally formed in the base; and
a second lamp movably attached to the base, wherein
the base, the first lamp, and the second lamp are movable as a whole with respect to the handle,
the second lamp is movable with respect to the base, the first lamp, and the handle,
the first lamp has a first position to emit light along a longitudinal direction of the handle and a second position to emit light along a direction perpendicular to the longitudinal direction,
the second lamp has a third position to emit light along the longitudinal direction and a fourth position to emit light along the direction perpendicular to the longitudinal direction,
the device is placeable on a surface while the longitudinal direction of the handle is maintained perpendicular to the surface, and
the first lamp is different from the second lamp.

US Pat. No. 10,280,827

ENGINE AND ENGINE-DRIVEN WORKING MACHINE

Koki Holdings Co., Ltd., ...

1. An engine comprising: a cylinder having a plurality of fins on an outer circumferential section thereof and in which a combustion chamber is formed; a cooling fan configured to generate cooling air to cool the cylinder; and a substantially rectangular parallelepiped muffler attached to the cylinder, wherein an exhaust gas outlet is installed in the muffler to discharge an exhaust gas along a first wall surface of the muffler in a direction perpendicular to an axial direction of the cylinder, a second wall surface is disposed at a downstream side in a discharge direction of the exhaust gas when seen from the first wall surface and extends in a direction crossing the first wall surface, a muffler cover configured to cover the muffler is provided, and first cooling air passing through and between the fins flows along the second wall surface and merges with the exhaust gas at the inside of an outer exterior edge position of the muffler cover.

US Pat. No. 10,263,228

ELECTRIC DEVICE INCLUDING SEALING MEMBER BETWEEN ATTACHMENT PART AND BATTERY PACK

Koki Holdings Co., Ltd., ...

1. An electric device comprising:a battery pack retaining a battery cell and having battery-side terminals; and
a device main body having an attachment part to/from which the battery pack is attached/detached, wherein
the device main body includes:
a guide mechanism which is provided to the attachment part and which regulates a direction in which the device main body and the battery pack are relatively moved to each other when the battery pack is attached/detached to/from the device main body,
a terminal holder which is provided to the attachment part and in which is embedded a plurality of device-side terminals mechanically connected to the battery-side terminals when the battery pack is attached to the attachment part; and
a seal member which is disposed between the attachment part and the terminal holder, the seal member preventing foreign substances from inside the device main body from entering between the attachment part and the terminal holder so that foreign substances are prevented from entering between the device-side terminals of the device main body and the battery-side terminals of the battery pack, and
the seal member is attached to an outer periphery of the terminal holder, and the terminal holder is clamped and fixed to the attachment part via the seal member.

US Pat. No. 10,260,453

TWO-CYCLE ENGINE AND ENGINE WORK MACHINE

Koki Holdings Co., Ltd., ...

1. A two-cycle engine, comprising a structure where, through descending of a piston, a mixed gas guided into a crank case is guided into a combustion chamber formed on an upper side of the piston through a scavenging passage, wherein the crank case is disposed to a lower side of the piston performing a reciprocal up-down movement in a cylinder, wherein in the two-cycle engine,a notch part is formed locally from a lower end side on a sidewall part of the piston sliding along an inner surface of the cylinder, the notch part is connected to the scavenging passage when the piston is located at a bottom dead center, a crank case protruding part is disposed in the crank case, and the crank case protruding part is located on a lower side of the scavenging passage and penetrates through the notch part and protrudes toward a central axis side of the cylinder when the piston is located at the bottom dead center,
wherein an uppermost part of the notch part is disposed closer to the upper side than a lower portion of a piston pin boss where a piston pin is installed in the piston, and the piston pin boss is an entire circular area supporting the piston pin.

US Pat. No. 10,325,475

ABNORMALITY REPORTING SYSTEM AND ELECTRIC TOOL, AND COMMUNICATION TERMINAL

KOKI HOLDINGS CO., LTD., ...

1. A system comprising:a power tool; and
a smart phone adapted to connect with the power tool via wireless communication, wherein,
when abnormality occurs in the power tool, the smart phone is configured to provide a report of the occurrence of abnormality, and
when the power tool and the smart phone are within a range where the wireless communication is available for the power tool and the smart phone to communicate with each other,
the power tool enters a locked state when a first signal is received from the smart phone via the wireless communication; and
the power tool enters a lock release state when a second signal is received from the smart phone via the wireless communication, and
the smart phone is configured to provide the report of the occurrence of abnormality, when the power tool and the smart phone are out of the range where the wireless communication is available for the power tool and the smart phone to communicate with each other.

US Pat. No. 10,286,462

CUTTING MACHINE

Koki Holdings Co., Ltd., ...

1. A cutting machine comprising:a cutting portion comprising:
a motor;
a motor housing accommodating the motor;
an output shaft configured to be rotated upon rotation of the motor, a cutting blade being configured to be detachably attached to the output shaft;
a battery pack serving as a power source of the motor; and
a battery pack attaching portion disposed on the motor housing and including a pair of rail portions with which the battery pack is engageable;
a base having a contact surface on which a workpiece is configured to be placed; and
a swing support mechanism connected to the base and the cutting portion and including a swing shaft extending in parallel to the output shaft, the swing support mechanism supporting the cutting portion such that the cutting portion is swingable about the swing shaft between a top dead center and a bottom dead center in a direction parallel to a side surface of the cutting blade;
wherein the motor housing is constituted by at least two split pieces each having a mating surface, the at least two split pieces contacting with each other at the mating surfaces, the pair of rail portions having one rail and another rail those individually positioned at different ones of the at least two split pieces, and
wherein the mating surface is parallel to an axial direction of a rotating shaft of the motor.

US Pat. No. 10,335,874

RECIPROCATING TOOL

KOKI HOLDINGS CO., LTD., ...

1. A reciprocating tool for moving a tip tool in a reciprocating direction to achieve a cutting action, comprising:a housing accommodating:
a motor;
a power transmission member, driven by the motor, revolving around a rotation axis crossing the reciprocating direction;
a plunger extending in the reciprocating direction, one end of the plunger holding the tip tool;
a connector coupling the power transmission member to another end of the plunger and converting a revolving motion of the power transmission member into a reciprocating motion of the plunger holding the tip tool in the reciprocating direction, the connector having a support member protruding from the connector in a direction perpendicular to the reciprocating direction;
a guide member fixed to the housing and extending along the reciprocating direction, wherein
the support member of the connector slidably and rockably engages with the guide member so that the guide member guides a movement of the connector to convert the revolving motion of the power transmission member into the reciprocating motion of the plunger, and
the connector supports the plunger to allow the plunger to move together with the connector.

US Pat. No. 10,320,214

POWER TOOL

Koki Holdings Co., Ltd., ...

1. A power tool configured to receive a secondary battery, the power tool comprising:a drive unit to which the secondary battery is connectable;
a voltage detecting unit configured to detect a battery voltage developed across the secondary battery;
a current detecting unit configured to detect a current flowing through the drive unit;
a storage device; and
a control unit configured to output a chopping control signal with a duty cycle changeable in accordance with the battery voltage detected by the voltage detecting unit, a voltage applied to the drive unit from the secondary battery being changed in accordance with the duty cycle changed by the control unit,
wherein the secondary battery is one of a plurality of batteries including a first battery and a second battery, wherein the second battery has a greater voltage than the
first battery; and
wherein the control unit is further configured to perform the following:
read a first allowable power dissipation value from the storage device;
set a first predetermined current value based on the first allowable power dissipation value and a detected battery voltage value of the first battery detected by the voltage detecting unit;
compare a current flowing in the drive unit detected by the current detecting unit to the first predetermined current value;
decrease the duty cycle of the chopping control signal when the detected current flowing in the drive unit has exceeded the first predetermined current value;
set a second predetermined current value, smaller than the first predetermined current value, based on the first allowable power dissipation value and a detected battery voltage value of the second battery detected by the voltage detecting unit;
compare the current flowing in the drive unit detected by the current detecting unit to the second predetermined current value; anddecrease the duty cycle of the chopping control signal when the detected current flowing in the drive unit has exceeded the second predetermined current value.

US Pat. No. 10,293,473

PORTABLE WORKING MACHINE

KOKI HOLDINGS CO., LTD., ...

1. A portable working machine comprising:a driving source;
a main body including the driving source;
a handle joined with the main body;
a fixing portion which is a protruding portion and being provided to one of the main body or the handle;
a vibration-proofing mechanism including an elastic body, the handle joined with the main body with the vibration-proofing mechanism and the fixing portion interposed therebetween;
a fixing member; and
a regulating portion provided to another of the main body or the handle;
wherein one longitudinal direction end of the elastic body of the vibration-proofing mechanism is fixed to a first side of the fixing portion by the fixing member, another longitudinal direction end of the elastic body of the vibration-proofing mechanism is fixed to the other of the main body or the handle, and a stopper portion configured to come into contact with the other of the main body or the handle to regulate a movement amount of the handle is provided at a second side of the fixing portion opposite to the first side of the fixing portion,
wherein the fixing member penetrates the fixing portion, and a portion of the fixing member protruding toward the second side of the fixing portion configures the stopper portion, and
wherein the stopper portion penetrates the regulating portion, and the stopper portion and an inner edge of the regulating portion is configured to conic into contact with each other to regulate the movement amount of the handle.