US Pat. No. 9,919,411

ACTIVE COOLING FOR POWER TOOL GRIPPING SURFACES

Nanjing Chervon Industry ...

11. A reciprocating saw comprising:
a housing having a front portion and a handle portion, the front portion defining a cavity that encloses a motor and including
a gripping portion surrounding the cavity, the handle portion including a switch configured to control power to the motor;

a reciprocating drive assembly coupled to the motor and including a tool holder located externally with respect to the housing,
the drive assembly being configured to impart a reciprocating drive motion to the tool holder in response to being driven
by the motor, the tool holder being configured to retain a working tool for performing work when the tool holder is driven
to move by the reciprocating drive assembly;

an insulating cover provided on the gripping portion of the housing, the insulating cover including a gripping surface; and
a thermoelectric cooling unit located between the gripping portion of the housing and the insulating cover, the thermoelectric
cooling unit comprising a pair of thermally conductive plates having two dissimilar semi-conductors arranged therebetween
and a first one of the pair of thermally conductive plates defining a cold side positioned in thermal contact with an inner
surface of the insulating cover and a second one of the pair of thermally conductive plates defining a hot side positioned
in contact with an outer surface of the gripping portion of the housing,

wherein the thermoelectric cooling unit is configured to absorb thermal energy from the insulating cover via the cold side
of the thermoelectric cooling unit and to release the absorbed thermal energy via the hot side of the thermoelectric cooling
unit.

US Pat. No. 9,923,492

ELECTRIC POWER TOOL AND MOTOR CONTROL METHOD THEREOF

Nanjing Chervon Industry ...

1. A motor control method for an electric power tool provided with a motor having no speed adjustment, comprising the process
of:
during continued operation of the motor:
measuring current flowing through the motor, the current being drawn from a power supply circuit which is operably coupled
to the motor and which draws power from a power supply;

determining when the motor is in a locked rotor condition;
decreasing a duty cycle of the power supply circuit while the power supply circuit continues to draw power from the power
supply when it is determined that the motor is in the locked rotor condition; and

increasing the duty cycle of the power supply circuit when the locked rotor condition is eliminated,
wherein the steps of decreasing and increasing the duty cycle of the power supply circuit are performed without removing power
from the power supply, thereby continuing operation of the motor and without stopping and restarting the motor.

US Pat. No. 10,440,882

GRASS TRIMMER, OPERATING METHOD THEREOF AND CONTROL METHOD THEREOF

Nanjing Chervon Industry ...

1. A grass trimmer, comprising:a trimming head;
a driving device for driving the trimming head to rotate so as to cut vegetation; and
an operating device configured for a user to operate to control the grass trimmer;
wherein the trimming head comprises a spool and a line holding member, the spool is used to wind a cutting line, and the line holding member includes a line holding structure allowing the cutting line to pass through or bypass,
wherein the driving device comprises a motor, the grass trimmer has a cutting mode for cutting vegetation and an auto-winding mode for winding the cutting line onto the spool, in the auto-winding mode, the motor drives at least one of the spool and the line holding member to make the spool and the line holding member rotate relatively to wind the cutting line on the spool, and
the operating device comprises a first operating element for activating the cutting mode and a second operating element for activating the auto-winding mode.

US Pat. No. 10,264,725

GRASS TRIMMER, OPERATING METHOD THEREOF AND CONTROL METHOD THEREOF

Nanjing Chervon Industry ...

1. A grass trimmer, comprising:a trimming head;
a motor connected with the trimming head;
an operating device or switch operably coupled to the motor; and
a power supply for supplying power to the motor;
wherein the trimming head comprises a spool and a line holding element, the spool is used to wind a trimming line and the line holding element is formed with a line holding structure,
wherein the grass trimmer has a cutting mode and an auto-winding mode controllable by the operating device or switch, in the cutting mode, the trimming head is driven by the motor to rotate so as to cut vegetation, and in the auto-winding mode, the line holding structure holds the trimming line while at least one of the spool or the line holding element is driven by the motor for producing relative rotation between the spool and the line holding element thereby winding the trimming line around the spool, and
wherein the operating device or switch is operable to control the motor and actuate the auto-winding mode, thereby winding the trimming line around or onto the spool.

US Pat. No. 9,975,233

POWER TOOL INCLUDING AN ACCESSORY

Nanjing Chervon Industry ...

1. A power tool, comprising:a motor configured to move a saw blade in a repeating pattern of movement;
a foot plate defining a saw blade opening, said foot plate including a plurality of walls that define a storage space, said plurality of walls including a first lateral wall and an opposite second lateral wall;
a detent system supported by said foot plate and having a detent member and a biasing element configured to bias said detent member toward said second lateral wall; and
an accessory defining (i) a first detent structure configured to receive said detent member therein, and (ii) a second detent structure configured to receive said detent member therein,
wherein said accessory is positionable in (i) a use position in which said accessory is spaced apart from said foot plate, and (ii) a storage position in which said accessory is located in said storage space,
wherein, during movement of said accessory from said use position to said storage position, said detent member is advanced (i) into said first detent structure, (ii) out of said first detent structure, and then (iii) into said second detent structure, and
wherein, during movement of said accessory from said storage position to said use position, said detent member is advanced (i) out of said second detent structure, (ii) into said first detent structure, and then (iii) out of said first detent structure,
wherein said accessory includes a plate having a top plate surface, a bottom plate surface, and a lateral side interposed between said top plate surface and said bottom plate surface,
wherein said top plate surface, said bottom plate surface, and said lateral side each define said first detent structure and said second detent structure,
wherein said accessory is interposed between said first lateral wall and said second lateral wall when said accessory is located in said storage position,
wherein said lateral side is parallel to said first lateral wall and said second lateral wall when said accessory is in said storage position,
wherein said biasing element is configured to bias said accessory toward said second lateral wall when said accessory is in said storage position,
wherein said movement of said accessory from said use position to said storage position automatically advances said detent member out of said first detent structure, and
wherein said movement of said accessory from said storage position to said use position automatically advances said detent member out of said second detent structure and out of said first detent structure.

US Pat. No. 10,277,064

POWER TOOL AND CONTROL METHOD THEREOF

Nanjing Chervon Industry ...

1. A power tool, comprising:a motor;
a first battery pack having a first battery;
a second battery pack having a second battery connected in parallel with the first battery;
a first battery receptacle for receipt of the first battery pack;
a second battery receptacle for receipt of the second battery pack;
a first switch device being connected between the first battery and the motor to form a first electrical connection between the first battery and the motor or cut off the first electrical connection between the first battery and the motor;
a second switch device being connected between the second battery and the motor to form a second electrical connection between the second battery and the motor or cut off the second electrical connection between the second battery and the motor;
a controller to
detect a first voltage drop across the first switch device along the current direction, and control the first switch device opened to cut off the first electrical connection between the second battery and the motor when the first voltage drop is less than a first control voltage;
detect a second voltage drop across the second switch device along the current direction, and control the second switch device opened to cut off the electrical connection between the second battery and the motor when the second voltage drop is less than a second control voltage, detect a voltage of the first battery pack, and cut off the connection of the first battery pack and the motor when the voltage of the first battery pack is less than a first voltage threshold; and
detect a voltage of the second battery pack, and cut off the connection of the second battery pack and the motor when the voltage of the second battery pack is less than a second voltage threshold.

US Pat. No. 10,256,701

ELECTRIC POWER TOOL AND METHOD FOR DRIVING BRUSHLESS MOTOR THEREOF

Nanjing Chervon Industry ...

1. An electric power tool comprising:a housing;
a brushless motor supported by the housing, the motor comprising a rotor and a stator winding including at least two phases; and
a driving system, comprising:
a driving circuit for driving the brushless motor;
position sensors for detecting positions of the rotor; and
a controller configured for controlling the driving circuit according to signals corresponding to the positions of the position sensors such that the rotor of the brushless motor, when rotating in a normal direction, sequentially passes by commutation positions, where the signal of at least one of the position sensors in the brushless motor changes, and a reference position, where a back electromotive force of at least one of the at least two phases of the stator winding in the brushless motor is at a midpoint position of a waveform of the back electromotive force;
wherein a difference between an electrical angle of one of the commutation positions and an electrical angle of the reference position ranges from 20° to 40°.

US Pat. No. 10,532,489

POWER TOOL

Nanjing Chervon Industry ...

1. A power tool, comprising:a housing;
a saw blade for cutting a workpiece;
a motor for driving the saw blade to rotate about a first axis, wherein the saw blade is disposed at a front side of the motor;
a circuit board for controlling the motor;
a heat sink for cooling; and
a base plate being formed with a flat surface for contacting with the workpiece during cutting,
wherein the housing comprises a first containing portion and a second containing portion, the first containing portion is formed with a first container for containing the motor, the second containing portion is formed with a second container which is communicated with the first container, the first containing portion has two ends along a direction perpendicular to the first axis, the second containing portion extends from one of the two ends of the first containing portion along a direction parallel to the flat surface, the circuit board and the heat sink are disposed in the second container, and
wherein the heat sink comprises a base board extending along the direction parallel to the flat surface, a plurality of first-type ribs disposed on a first surface of the base board and a plurality of second-type ribs disposed on the first surface, the first surface extends along the direction parallel to the flat surface, a first-type channel is formed between two adjacent first-type ribs, one end of the first-type channel is defined as a first-type air outlet, a second-type channel is formed between two adjacent second-type ribs, one end of the second-type channel is defined as a second-type air outlet, the extending direction of the first-type ribs is parallel to the extending direction of the second-type ribs, the first container comprises a first area for placing the motor and a second area disposed at a rear side of the motor, the first-type air outlet is open towards the second area, a first airflow from the first-type air outlet flows to the second area and then to the first area, the second-type air outlet is open towards the first area, the end of the second-type ribs close to the motor is shorter than the end of the first-type ribs close to the motor so that a guiding channel is formed between the second-type air outlet and the motor, and the guiding channel guides a second airflow from the second-type air outlet flows to the second area.

US Pat. No. 10,272,506

RECIPROCATING TOOL WITH LINEAR GUIDES

Nanjing Chervon Industry ...

1. A reciprocating saw, comprising:a housing;
a plunger at least partially positioned within the housing and configured to reciprocate with respect to the housing along a plunger axis;
a wobble plate assembly operably connected to the plunger and a motor;
a first guide rail supported by the housing and extending longitudinally along the plunger axis;
a spherical component in contact with the first guide rail, the spherical component and the first guide rail configured to inhibit rotation of the wobble plate assembly,
wherein:
the spherical component comprises a first ball bearing,
the first guide rail is fixedly attached to a first side of the housing,
the first ball bearing is in contact with a counterweight, and
the counterweight is operably connected to an anti-rotation arm of the wobble plate assembly;
a second guide rail fixedly attached to a second side of the housing, the counterweight located between the first side of the housing and the second side of the housing;
a second ball bearing in contact with the counterweight and in contact with the first guide rail; and
a third ball bearing in contact with the counterweight and in contact with the second guide rail.

US Pat. No. 10,439,415

POWER STATION

Nanjing Chervon Industry ...

1. A power station, comprising:an adaptor comprising:
a housing having a top portion, a bottom portion opposite to the top portion, a first end portion, and a second end portion, the first and second end portions disposed between the top and bottom portions, and a first side portion and a second side portion respectively disposed on either side of the first end portion;
a battery pack interface disposed on the first side portion and configured to removably receive at least one battery pack, the at least one battery pack being originally used as a power source for a handheld electric power tool or a garden tool;
a plurality of connecting bars respectively connected between the top portion and the bottom portion and disposed on the first side portion and the second side portion such that the battery pack is positioned between two connecting bars when connected to the battery pack interface;
an electrical energy output port unit disposed on the first end portion, the electrical energy output port unit comprising:
at least one AC output port adapted to output an alternating current; and
at least one DC output port adapted to output a direct current;
a discharging or discharging regulator unit configured to couple the at least one battery pack to the AC output port or the DC output port, the discharge or discharging regulator unit comprising:
a first AC discharging regulator provided between the at least one battery pack and the at least one AC output port and configured to receive the electrical energy from the at least one battery pack and selectively transmit the electrical energy supplied by the at least one battery pack to the at least one AC output port; and
a second DC discharging regulator provided between the at least one battery pack and the at least one DC output port and configured to receive electrical energy from the at least one battery pack and selectively transmit the electrical energy supplied by the at least one battery pack to the at least one DC output port; and
a control circuit or control circuit unit comprising a discharging control module,
wherein the discharging control module is coupled to the discharging or discharging regulator unit for performing discharging control of the discharging or discharging regulator unit such that the discharging regulator unit coupled to the at least one battery pack is configured to selectively transmit discharge power to the at least one AC output port or the at least one DC output port.

US Pat. No. 10,277,093

POWER TOOL AND CIRCUIT BOARD

NANJING CHERVON INDUSTRY ...

1. A printed circuit board assembly, comprising:a main board having at least two conductive portions and an insulation portion all of which are exposed to a surface of the main board;
at least one semiconductor power device mounted on the main board; and
at least two conductors, each attached to a respective one of the conductive portions;
wherein the conductive portions electrically connect to the semiconductor power device, and the conductors electrically connect to the conductive portions,
and wherein the at least one semiconductor power device comprises:
a first connect pin connecting to a first one of the conductive portions which is electrically connected to a first one of the conductors;
a second connect pin connecting to second one of the conductive portions which is electrically connected to a second one of the conductors; and
a control pin for controlling the electrical connection between the first connect pin and the second connect pin.

US Pat. No. 10,923,938

CHARGING DEVICE AND CHARGING METHOD

Nanjing Chervon Industry ...

1. A charging device for charging an electric energy storage device, comprising:a power supply circuit, which is connected to a power supply;
an alternating current conversion circuit, which is configured to convert a current from the power supply connected to the power supply circuit to a first alternating current with a preset frequency value;
a capacitor electrically coupled between the power supply circuit and the alternating current conversion circuit;
a high-frequency transformer, which is configured to convert the first alternating current to a second alternating current, wherein the high-frequency ranges from 5 kHz to 1 MHz and a voltage value corresponding to the second alternating current is less than a voltage value corresponding to the first alternating current; and
a direct current voltage conversion circuit, which is configured to convert the second alternating current to a direct current with a waveform fluctuating in a preset range, so as to charge the electric energy storage device,
wherein the alternating current conversion circuit is connected to the power supply circuit, the transformer is connected to the alternating current conversion circuit, and the direct current voltage conversion circuit is connected to the transformer, and
wherein the capacitor is an electrolytic capacitor and the value range of the electrolytic capacitor (CY) is 330 nF

US Pat. No. 10,770,993

POWER TOOL

Nanjing Chervon Industry ...

1. A power tool, comprising:a motor, comprising a stator and a rotor;
a transmission device, configured to connect the rotor to a tool accessory;
a drive circuit, configured to output a switch signal to drive the rotor of the motor to operate;
a control unit, configured to output a drive signal to control the drive circuit; and
a power supply device, configured to supply power to the motor, the drive circuit, and the control unit;
wherein the control unit is configured to determine a variable ?PWM of a duty ratio according to a variable ?x of a characteristic parameter of the motor, wherein the variable ?PWM of the duty ratio is obtained by a function f(?x) and is within a range of 0.01 to 0.1, and according to the variable ?PWM of the duty ratio, output the drive signal to the drive circuit to control the rotor of the motor to operate to output a driving force.

US Pat. No. 10,639,758

POWER TOOL

Nanjing Chervon Industry ...

1. A power tool, comprising:a tool main body comprising a first motor for outputting power to a tool attachment; and
a dust collecting device comprising:
a fan;
a second motor for driving the fan to rotate so as to generate an absorbing force;
a connecting assembly for detachably connecting the dust collecting device with the tool main body; and
a dust collecting housing connected movably with the connecting assembly in a front and rear direction;
wherein the second motor comprises:
a stator; and
a rotor being capable of rotating relative to the stator about a first axis substantially perpendicular to the front and rear direction; and
wherein the dust collecting housing comprises:
a main housing forming a first containing chamber for containing the fan; and
a dust box detachably couplable to the main housing and forming a second containing chamber for containing dust absorbed by the dust collecting device, and
wherein the second motor and the dust box are disposed on opposite sides of the fan in a direction of the first axis.

US Pat. No. 10,792,780

SANDER

Nanjing Chervon Industry ...

1. A sander, comprising:a motor comprising a motor shaft configured to rotate around a first axis;
a housing comprising an accommodating portion configured to accommodate the motor;
a battery pack configured to power the motor;
a baseplate comprising a baseplate plane configured to arrange sandpaper thereon; and
a driving assembly configured to drive the baseplate to make an eccentric motion,
wherein the housing further comprises:
a first grip portion configured to be gripped by one hand of a user;
a second grip portion configured to be gripped by the other one hand of the user; and
a coupling portion for detachably coupling the battery pack to the housing,
wherein the battery pack is located between the first grip portion and the second grip portion when the battery pack is coupled to the housing,
wherein the first grip portion, the battery pack, and the second grip portion are aligned along a straight line parallel to the baseplate plane, and
wherein the first grip portion extends in the straight line and a length of the first grip portion in the straight line is greater than a length of the second grip portion in the straight line, and
wherein the housing further comprises a connecting portion configured to connect the first grip portion to the accommodating portion and the connecting portion is provided with a receiving space for receiving the battery pack.

US Pat. No. 10,792,836

CONCRETE CUTTER WITH DEPTH SETTING AND RETENTION SYSTEM

Nanjing Chervon Industry ...

1. A power tool, comprising:a base plate configured to move along a surface of a workpiece, the base plate comprising:
a pivot mount; and
a first retaining member that defines an arcuate slot extending along a direction normal to a plane of the base plate;
a housing configured to receive a cutting tool, the housing comprising:
a pivoting member that is engaged with the pivot mount so as to pivotably mount the housing on the base plate about a pivot axis parallel to the plane of the base plate; and
a second retaining member received in the arcuate slot of the first retaining member, such that the arcuate slot guides a pivoting motion of the housing about the pivot axis;
a stop member configured to be selectively positioned at different locations along the arcuate slot separately from the second retaining member, and configured to delimit an extent of the pivoting motion of the housing toward the workpiece when the second retaining member abuts the stop member such that the position of the stop member along the arcuate slot defines a cut depth for the cutting tool; and
a spring having a first end engaged with the base plate and a second end engaged with the housing, the spring configured to exert a spring force that acts against a weight of the housing,
wherein the housing has a center of mass located between the first retaining member and the pivot mount and such that the weight of the housing is acted on by gravity along a direction of the workpiece, and
wherein a resultant force of the spring force allows the housing, when no other forces are applied to the housing, to be biased away from the base plate about the pivot axis to support the housing during operation of the cutting tool without the housing being biased about the pivot axis fully along the entire length of the arcuate slot.

US Pat. No. 10,767,326

AUGER FOR A SNOW THROWER

Nanjing Chervon Industry ...

1. An auger for use in a snow thrower, said auger comprising:a supporting shaft having a central axis;
a snow throwing bracket secured to a middle portion of the supporting shaft and configured to throw snow;
a left snow scraper surrounding the supporting shaft, secured to a left end of the snow throwing bracket and configured to push snow to the right towards a region where the snow throwing bracket is located;
a right snow scraper surrounding the supporting shaft, secured to a right end of the snow throwing bracket and configured to push snow to the left towards the region where the snow throwing bracket is located;
a left supporting plate secured to a left end of the supporting shaft, wherein two ends of the left snow scraper are respectively secured to the snow throwing bracket and the left supporting plate;
a right supporting plate secured to a right end of the supporting shaft, wherein two ends of the right snow scraper are respectively secured to the snow throwing bracket and the right supporting plate;
a left auxiliary supporting plate provided separately from the snow throwing bracket to form a first gap between the left auxiliary supporting plate and the snow throwing bracket in a direction of the central axis, wherein the left auxiliary supporting plate is arranged separately from the left supporting plate to form a second gap between the left auxiliary supporting plate and the left supporting plate in the direction of the central axis, and the left auxiliary supporting plate is located between the snow throwing bracket and the left supporting plate; and
a right auxiliary supporting plate provided separately from the snow throwing bracket to form a third gap between the right auxiliary supporting plate and the snow throwing bracket in the direction of the central axis, wherein the right auxiliary supporting plate is arranged separately from the right supporting plate to form a forth gap between the right auxiliary supporting plate and the right supporting plate in the direction of the central axis, and the right auxiliary supporting plate is located between the snow throwing bracket and the right supporting plate,
wherein the left snow scraper and the right snow scraper are symmetrical about a plane perpendicular to the central axis, an angle of the left snow scraper around the central axis is greater than 180 degrees and smaller than 360 degrees, and a ratio of the angle of the left snow scraper around the central axis to a length of the left snow scraper in a direction of the central axis is greater than or equal to 0.9 degree/mm and less than or equal to 3 degree/mm, and
wherein the left auxiliary supporting plate is secured to the supporting shaft, a middle portion of the left snow scraper is secured to an end of the left auxiliary supporting plate, the right auxiliary supporting plate is secured to the supporting shaft, and a middle portion of the right snow scraper is secured to an end of the right auxiliary supporting plate.

US Pat. No. 10,759,080

ELECTRIC TOOL

Nanjing Chervon Industry ...

1. An electric tool, comprising:a rotatable, working accessory;
a motor configured to drive the working accessory to rotate;
a case comprising a motor case portion for accommodating the motor and a main handle portion for gripping; and
a fan arranged on one side of the motor away from the working accessory;
wherein an airflow inlet and an airflow outlet are formed in the case whereby, when the fan operates, an airflow at the airflow inlet is taken out and is directed to the airflow outlet after the airflow flows through the motor, the motor case portion comprises an encircling portion which encircles the motor and an end portion arranged on one end of the encircling portion, and the case further comprises a coupling portion for coupling with a battery pack and a connecting portion for connecting the coupling portion and the motor case portion, and the airflow inlet is arranged at the connecting portion,
wherein the motor comprises a stator fixed relative to the case, a motor shaft arranged in the case rotatably about a motor axis, and a rotor which surrounds the stator and rotates synchronously with the motor shaft,
wherein the electric tool further comprises a stopping piece comprising a stopping portion arranged at a first clearance between the rotor and the encircling portion and a projection of the stopping piece in a plane perpendicular to a rotating axis of the rotor is at least partially located outside a projection of the rotor in the plane, and
wherein the fan is disposed at the rear side of the rotor, at least a portion of the stopping piece is disposed at the front side of the motor, the airflow passes through the inside of the rotor along a first direction from the front side of the motor to the rear side of the motor, and the stopping portion is arranged at the first clearance between the rotor and the encircling portion to stop the airflow from the fan from flowing back outside the rotor along a second direction opposite of the first direction.

US Pat. No. 10,638,666

POWER TOOL AND TRANSMISSION SHAFT ASSEMBLY THEREOF

Nanjing Chervon Industry ...

1. A power tool, comprising:a motor;
a work attachment driven by the motor to perform a function of the power tool; and
a transmission device for connecting the motor and the work attachment to transmit power of the motor to the work attachment;
wherein the transmission device comprises a transmission shaft assembly, the transmission shaft assembly comprising:
a connecting tube extended along a central axis;
a transmission shaft, comprising a rigid shaft, which extends along the central axis and which is disposed in the connecting tube;
a first limiting element disposed on an end of the connecting tube and formed with a first hole allowing the transmission shaft to pass there through;
a second limiting element disposed on the other end of the connecting tube and formed with a second hole allowing the transmission shaft to pass there through;
a bushing comprising a main body formed with a channel extended along the central axis and several projecting parts disposed on the periphery of the main body;
a first biasing element applying a force on the bushing along the central axis; and
a first bearing that is sleeve-connected on the outside of the transmission shaft,
wherein the bushing is located in the connecting tube and disposed between the first limiting element and the second limiting element such that the transmission shaft passes through the first hole, the channel, and the second hole successively, and
wherein the first biasing element and the first bearing are disposed between the bushing and the first limiting element and the first biasing element is a rubber element that is sleeve-connected on the outside of the first bearing.

US Pat. No. 10,485,166

POWER TOOL

Nanjing Chervon Industry ...

9. A lawn mower, comprising:a functional device comprising a first housing and a deck; and
a power device comprising a second housing and a motor,
wherein the functional device further comprises a frame for supporting the first housing, and the first housing, the deck and the frame constitute a whole which is connected with an operating component,
wherein the power device further comprises multi battery packs detachably mounted on the second housing, the motor is contained in the second housing, and when the battery packs are mounted on the second housing the motor is located between the battery packs,
wherein each of the battery pack comprises a plurality of cells, each of the battery packs is individually detachable for use by other power tools, at least one cover is pivotally connected to the second housing for covering, and allowing access to, the battery packs, and the second housing is provided with or connected with a locking structure for locking the cover, and
wherein the battery pack comprises a battery pack electrical interface which is at least used to allow the battery packs to output electricity, the second housing comprises a device electrical interface for coupling with the battery pack electrical interface and allowing the electricity of the battery packs to be supplied to the motor, the device electrical interface is located between the motor and the battery packs when the battery packs are coupled with the second housing, and the device electrical interface is located between the battery packs when the battery packs are coupled with the second housing.

US Pat. No. 10,478,933

ANGLE GRINDER, POWER TOOL AND BRAKING METHOD THEREOF

Nanjing Chervon Industry ...

1. An angle grinder, comprising:a motor comprising a rotor and windings;
a power supply for supplying power to the motor;
a main switch for turning on/off an electrical connection between the windings of the motor and the power supply;
an output shaft driven by the rotor to rotate;
a rotor brake circuit for slowing down the rotor of the motor when the windings are short circuited or reverse connected;
an output shaft brake circuit for producing a magnetic field to slow down the output shaft; and
a controller for detecting whether the rotor brake circuit short circuits or reverse connects the windings;
wherein when the windings are short circuited or reverse connected for a time which reaches a preset value, the output shaft brake circuit produces the magnetic field to slow down the output shaft.

US Pat. No. 10,405,707

BLOWER

Nanjing Chervon Industry ...

1. A blower, comprising:an axial fan for generating airflow;
wherein the axial fan comprises:
a center hub capable of rotating around a central axis; and
a plurality of blades that extend outward from the center hub in a radial direction and that are arranged around the central axis;
wherein the plurality of blades and the center hub are integrated as a whole, each of the plurality of blades is provided with a suction surface and a pressure surface for generating airflow, two opposite ends of the suction surface and a pressure surface are intersected to form a front edge and a rear edge, and the front edge is in the front of the rear edge in a rotation direction of the axial fan, the front edge has a point close to the center hub which is defined as a root point, the front edge has another point far from to the center hub which is defined as a tip point, a line passing the root point and intersecting vertically with the central axis is defined as an axis Y, the central axis is defined as an axis Z, a line intersecting vertically with the axis Y and the axis Z is defined as an axis X, a projection of the front edge in a plane constituted by the axis X and the axis Y is extended outward in a radial direction of the central axis and extended forward in the rotation direction of the axial fan, a projection of the front edge in a plane constituted by the axis Z and the axis Y is extended outward in a radial direction of the central axis and extended toward a side of the axial fan from which the air is entered, an angle between a tangent line of a projection of the front edge in the plane constituted by the axis X and the axis Y at the tip point and the axis Y is greater than or equal to 5° and less than or equal to 15°, and an angle between a tangent line of a projection of the front edge in the plane constituted by the axis Z and the axis Y at the tip point and the axis Y is greater than or equal to 15° and less than or equal to 25°.

US Pat. No. 10,888,939

MITER SAW

Nanjing Chervon Industry ...

1. A miter saw, comprising:a base;
a worktable arranged on the base and defining a worktable plane;
a cutting head formed with or connected to an operating member operable by a user, wherein the cutting head further comprises a circular saw blade rotatable around a first axis and a motor for driving the circular saw blade; and
a fence arranged on the worktable;
wherein the cutting head is connected with a first guiding member configured to guide chips to be discharged, the fence is formed with a guiding portion, the cutting head is operative to rotate around a second axis parallel to the worktable plane, and in response to the cutting head rotating around the second axis, the guiding portion is operative to guide the first guiding member to cross the fence.

US Pat. No. 10,890,229

POWER TOOL

Nanjing Chervon Industry ...

1. A power tool, comprising:a housing formed with a main handle configured for being held by a user;
a motor arranged inside the housing and comprising a driving shaft;
a working head comprising an output shaft wherein the output shaft is driven by the motor; and
a transmission assembly configured for transmitting power between the driving shaft and the output shaft;
wherein the power tool further comprises:
an auxiliary handle, comprising:
a front end mounted onto the housing at a position adjacent to the working head;
a gripping portion extending along a center line;
a vibration damping assembly comprising at least one mass member and a plurality of elastic elements; and
an end cap arranged at a rear end of the gripping portion;
wherein the rear end is farther away from the housing relative to the front end, the end cap defines an accommodating cavity configured for accommodating at least part of the vibration damping assembly, and the plurality of elastic elements are arranged between the at least one mass member and a cavity wall of the accommodating cavity, wherein a ratio of a natural frequency W1 of the vibration damping assembly to a rotational frequency W2 of the output shaft in rotation is greater than or equal to 0.7 and less than or equal to 1.3.

US Pat. No. 10,869,424

POWER TOOL, LAWN MOWER, AND CONTROL METHOD THEREOF

Nanjing Chervon Industry ...

1. A self-propelled lawn mower, comprising:a blade configured to cut grass;
a chassis configured to accommodate the blade;
a front wheel connected to a front side of the chassis;
a rear wheel connected to a rear side of the chassis;
a motor at least configured to drive the rear wheel to rotate;
a detection apparatus configured to detect a rotational speed of the front wheel; and
a controller configured to control the motor to decelerate when the rotational speed of the front wheel decreases, wherein
the motor is operably connected to the rear wheel, and the detection apparatus is electrically connected to the controller.

US Pat. No. 10,744,632

POWER TOOL

Nanjing Chervon Industry ...

1. A power tool, comprising:an output member configured to output power;
a motor configured to drive the output member;
a housing configured to accommodate the motor;
a transmission device configured to transmit power between the motor and the output member and having at least four transmission states in which the output member is capable of outputting different power; and
a shifting device configured to drive the transmission device to switch between different ones of the at least four transmission states;
wherein the shifting device comprises:
a first shifting element capable of switching between at least a first position and a second position in which the transmission device is in respective first and second ones of the at least four transmission states;
a second shifting element capable of switching between at least a third position and a fourth position in which the transmission device is in respective third and fourth ones of the at least four transmission states;
an operation member operated by a user, wherein the operation member can slide relative to the housing in a first straight line and rotate relative to the housing about a central axis; and
a connecting member for connecting the operation member to the second shifting element;
wherein, when the operation member slides relative to the housing, the operation member drives the first shifting element to switch between the first position and the second position whereupon a position of the second shifting element remains unchanged and, when the operation member rotates relative to the housing, the connecting member drives the second shifting element to switch between the third position and the fourth position whereupon a position of the first shifting element remains unchanged.

US Pat. No. 10,525,582

POWER TOOL

Nanjing Chervon Industry ...

1. A power tool, comprising:a housing;
a power output element for outputting power to drive a working attachment for performing a working function in a work area;
a motor for driving the power output element to output power to drive the working attachment; and
a surface light source device mountable to the housing for providing illumination to the work area when the working attachment is attached to the power output element, the surface light source device comprising:
a light exit surface allowing the surface light source device to emit light to the work area;
a light guiding element formed with the light exit surface for giving out light in the form of flood light;
a light incident surface for directing the light into the light guiding element; and
a light emitting element disposed at the light incident surface.

US Pat. No. 10,923,933

POWER STATION

Nanjing Chervon Industry ...

1. A power station, comprising:an adaptor having an electrical energy input interface for receiving electrical energy from a power supply device, the adaptor comprising:
a housing;
a protecting frame provided outside of the housing;
an electrical energy storage unit; and
an electrical energy output port unit disposed on the housing, the electrical energy output port unit comprising:
at least one AC output port adapted to output an alternating current; and
at least one DC output port adapted to output a direct current;
a charging or charging regulator unit configured to couple the electrical energy input interface to the electrical energy storage unit and to charge the electrical energy storage unit with the electrical energy received from the electrical energy input interface;
a discharging or discharging regulator unit configured to couple the electrical energy storage unit to the electrical energy output port unit, the discharging or discharging regulator unit comprising:
a first AC discharging regulator provided between the electrical energy storage unit and the at least one AC output port and configured to receive the electrical energy from the electrical energy storage unit and selectively transmit the electrical energy supplied by the electrical energy storage unit to the at least one AC output port; and
a second DC discharging regulator provided between the electrical energy storage unit and the at least one DC output port and configured to receive electrical energy from the electrical energy storage unit and selectively transmit the electrical energy supplied by the electrical energy storage unit to the at least one DC output port; and
a control or control circuit unit comprising a charging control module and a discharging control module,
wherein the charging control module is coupled to the charging or charging regulator unit for performing charging control of the charging or charging regulator unit;
wherein the discharging control module is coupled to the discharging or discharging regulator unit for performing discharging control of the discharging or discharging regulator unit such that the discharging or discharging regulator unit coupled to the electrical energy storage unit is configured to selectively transmit discharge power to the at least one AC output port and/or the at least one DC output port;
wherein a ratio between a voltage of the electrical energy storage unit and a voltage of the alternating current outputted by the adaptor ranges from 0.07 to 1.5;
wherein a ratio between the voltage of the electrical energy storage unit and a voltage of the direct current outputted by the adaptor ranges from 0.5 to 32;
wherein a ratio between a total power outputted by the power station and a total weight of the power station ranges from 20 Wh/kg to 75 Wh/kg;
wherein the housing comprising a top wall, a bottom wall and opposite side walls located between the top wall and the bottom wall, the power station comprises two handles attached to the housing, the two handles is configured to extend between the opposite side walls of the housing and respectively located at two sides of the top wall such that the power station becomes a portable device for a user to carry the total weight of the power station by the two handles, and
wherein the protecting frame comprises a top seat, a bottom seat, and supporting columns respectively connected between the top seat and the bottom seat and disposed proximate a first side portion of the housing and a second side portion of the housing, the protecting frame defining a central plane, and the supporting columns arranged symmetrically with respect to the central plane.

US Pat. No. 10,898,985

POWER TOOL

Nanjing Chervon Industry ...

1. A power tool, comprising:a motor, comprising a stator and a rotor;
a transmission device, operably connected to the rotor and configured to output a power to drive a tool accessory;
a driving circuit, configured to output an on-off signal to drive the rotor of the motor to operate;
a control unit, configured to output a driving signal to control the driving circuit;
a rectifier module, configured to convert an alternating current (AC) power to a direct current (DC) power to power up the motor, the driving circuit, and the control unit; and
a capacitor circuit, connected between the rectifier module and the driving circuit;
wherein the capacitor circuit comprises a capacitor C and a power switch transistor Q that are connected in series;
and the control unit is electrically connected to the power switch transistor Q and is configured to output a pulse width modulation (PWM) duty cycle signal depending on a characteristic parameter related to a rotational speed of the motor to control the power switch transistor Q to be turned on and off.

US Pat. No. 10,903,730

POWER TOOL

Nanjing Chervon Industry ...

1. A power tool, comprising:a motor, comprising:
a rotor rotatable about a central axis; and
a stator comprising a ring-shaped yoke portion and a plurality of teeth formed by protruding from an inner side or an outer side of the ring-shaped yoke portion;
a plurality of first windings wound around part of the plurality of teeth;
a plurality of second windings wound around another part of the plurality of teeth;
a first power source access circuit operably couplable to access a first power source with a first voltage;
a first drive circuit, comprising:
a plurality of first electronic switches connected between the plurality of first windings and the first power source access circuit;
a second power source access circuit operably coupled to access a second power source with a second voltage; and
a second drive circuit, comprising:
a plurality of second electronic switches connected between the plurality of second windings and the second power source access circuit,
wherein the plurality of first windings and the plurality of second windings are spaced in a circumferential direction of the central axis, and
wherein the first power source accessed by the first power source access circuit is a direct current power source, the second power source accessed by the second power source access circuit is an alternating current power source, the plurality of first windings form an angular connection, and the plurality of second windings form a star connection.

US Pat. No. 10,892,691

CONTROL CIRCUIT AND POWER TOOL

Nanjing Chervon Industry ...

1. A control circuit for a motor including a stator winding and a rotor, the control circuit having a driving state and a braking state and comprising:a main control switch, wherein the control circuit enters the driving state in response to the main control switch being closed and enters the braking state in response to the main control switch being opened;
a driving branch, comprising a first branch formed by the stator winding, a driving switch, and the rotor, wherein the driving branch is configured to control a connection between the stator winding and the rotor to be turned on or off;
a braking branch, comprising a second branch formed by the stator winding, a braking switch, and an electrical energy storage component, wherein the electrical energy storage component is configured to provide an electrical energy to the braking branch and is arranged between two terminals of the rotor; and
a control unit, electrically connected to the main control switch, to the driving switch, and to the braking switch, separately, configured to control the main control switch, the driving switch, and the braking switch to be closed or opened,
wherein the connection between the stator winding and the rotor of the driving branch is turned on in response to detecting that, in the braking state, a braking parameter of the braking branch exceeds a predetermined value, and
wherein the braking branch is further provided with a current detecting unit configured to detect, under the braking state, whether a braking current in the braking branch exceeds a preset threshold and the control circuit is configured to control the braking switch to stay in an open state in response to the current detecting unit detecting that the braking current in the braking branch exceeds the preset threshold to cut off a connection between the electrical energy storage component and the stator winding.

US Pat. No. 10,892,449

BACKPACK TOOL SYSTEM AND BACKPACK POWER SUPPLY APPARATUS THEREOF

Nanjing Chervon Industry ...

1. A backpack power supply apparatus, comprising:a battery pack for providing electric energy;
a body for supporting the battery pack, wherein the battery pack is detachably connected to the body, the body is at least partially symmetrical about a plane, and the body defines a height in a heightwise direction;
a wearable device connected to the body and wearable by a user to carry the body, wherein the wearable device comprises a strap, the strap comprises an upper end connected to an upper portion of the body, and the upper end of the strap applies a force to the body when the user wears the wearable device;
an electric energy transmission device electrically coupled to the battery pack for outputting the electric energy of the battery pack, wherein the electric energy transmission device is provided with a first electric energy output interface; and
a securing member for securing the first electric output interface,
wherein an included angle between a projection of a direction of the force on the plane and the heightwise direction is greater than or equal to 30 degrees and less than or equal to 50 degrees, and
wherein the securing member is secured to the wearable device or the battery pack, the electric energy transmission device comprises a cable, the first electric energy output interface is disposed at an end of the cable, the securing member is provided with a first securing slot for securing the cable and a second securing slot for securing the first electric energy output interface, and an opening of the second securing slot is larger than an opening of the first securing slot.

US Pat. No. 10,856,466

GRASS TRIMMING HEAD AND GRASS TRIMMER HAVING THE SAME

Nanjing Chervon Industry ...

1. A grass trimming head, comprising:a housing assembly, formed with a housing cavity and provided with an outer aperture for allowing a cutting line to be inserted from an outside of the housing assembly into the housing cavity; and
a spool, at least a portion of which is arranged inside the housing cavity and which is rotatable with respect to the housing assembly about a central axis; wherein the spool is provided with an inner aperture for allowing the cutting line to be inserted into the spool or a clamping portion configured to fix the cutting line;
wherein the spool comprises an upper spool portion and a lower spool portion, the upper spool portion comprises an upper winding portion configured for winding the cutting line, a first flange portion connected to an upper end of the upper winding portion, and a second flange portion connected to a lower end of the upper winding portion, the lower spool portion comprises a lower winding portion configured for winding the cutting line, a third flange portion connected to an upper end of the lower winding portion, and a fourth flange portion connected to a lower end of the lower winding portion, and the upper spool portion is coupled to the lower spool portion to form a line guide passage configured for the cutting line to pass through the spool.

US Pat. No. 10,525,577

POWER TOOL

Nanjing Chervon Industry ...

1. A power tool, comprising:a housing;
a prime mover disposed in the housing;
a first cylinder formed with a first chamber;
a first rotating member rotatable with respect to the first cylinder about a first axis under a driving force of the prime mover; and
a first piston movable in a direction parallel to the first axis when the first rotating member rotates relative to the first cylinder;
wherein the first cylinder and the first rotating member are disposed within the housing, the first piston is disposed within the first chamber, the first rotating member is formed with a first transmission structure to drive the first piston, and the first piston is formed with a second transmission structure capable of cooperating with the first transmission structure to rotate the first rotation member to drive the first piston.

US Pat. No. 10,524,417

WALK-BEHIND, SELF-PROPELLED MACHINE

Nanjing Chervon Industry ...

1. A walk-behind, self-propelled machine comprising:a chassis;
a handle connected to the chassis;
a plurality of wheels for supporting the chassis and being rotatable relative to the chassis;
a first motor mounted to the chassis and used for providing a driving force for rotating the plurality of wheels;
a working element, movable relative to the chassis to implement the function of the walk-behind, self-propelled machine;
a second motor for driving the working element to move; and
a transmission mechanism connecting the first motor with the plurality of wheels and comprising:
a clutch for realizing one-way transmission between the first motor and the plurality of wheels, wherein the clutch has a driving state where the first motor drives the plurality of wheels to rotate and an unlocked state where the plurality of wheels are free to rotate relative to the first motor, and the clutch comprising:
a movable member capable of moving between a locked position and an unlocked position; and
a driving member which transmits power to the plurality of wheels by means of friction;
wherein, when the movable member is in the locked position the clutch is in the driving state where the first motor is capable of driving the plurality of wheels to rotate in a first direction, when the movable member is in the unlocked position the clutch is in the unlocked state, and when the first motor stops rotating, the plurality of wheels rotate in a second direction opposite to the first direction and can drive the driving member to move so that the driving member pushes the movable member to move from the locked position to the unlocked position.