Patent Description:
The present application relates to a power tool, for example, a torque output tool.

One example is <CIT>, that shows the preamble of claim <NUM>.

A torque output tool is used for providing torque to assist a user in daily operations. Generally, a deceleration device needs to be provided between a motor and an output shaft so that the output shaft can output an appropriate rotational speed and appropriate torque. In order that the deceleration device can provide a sufficient gear ratio for deceleration, the deceleration device generally needs to be designed as a three-layer planetary gear train. The three-layer planetary gear train is not conducive to the reduction of the whole machine of the torque output tool. If a traditional double-layer planetary gear train is provided to achieve a high gear ratio, gear strength will decrease. If the double-layer planetary gear train is provided to achieve a low gear ratio, the requirement of an output system for deceleration cannot be satisfied.

The present application provides a torque output tool in which an output shaft can output a relatively low rotational speed through the transmission of a double-layer planetary gearset, thereby reducing an overall dimension of the torque output tool. The present application provides a torque output tool. The torque output tool includes an output shaft, a motor, a transmission assembly, and a gearbox. The output shaft is used for outputting torque. The motor is used for driving the output shaft to rotate around a first axis. The transmission assembly is used for transmitting output of the motor to the output shaft. The gearbox is used for accommodating the transmission assembly. The transmission assembly includes a first planetary gearset and a second planetary gearset. The first planetary gearset includes first planet gears and a first planet carrier. The first planet gears are driven by the motor, and the first planet carrier is used for mounting the first planet gears. The second planetary gearset includes second planet gears and a second planet carrier. The second planet carrier is used for mounting the second planet gears. The transmission assembly is capable of being switched to a first state and a second state such that the transmission assembly outputs a first gear ratio or a second gear ratio separately, where the first gear ratio is greater than the second gear ratio. The motor includes a motor shaft that rotates around the first axis. The transmission assembly includes a sun gear fixedly connected to the motor shaft. A first planet gear of the first planet gears includes an external engagement portion and an internal engagement portion. The external engagement portion forms external engagement with the sun gear. The internal engagement portion is fixed connected to the external engagement portion. A length of the gearbox in an axial direction of the first axis is configured to be greater than or equal to <NUM> and less than or equal to <NUM>.

Optionally, a first-stage internal ring gear forms internal engagement with the internal engagement portion, where the first-stage internal ring gear in a radial direction of the first axis at least partially overlaps with a projection of the internal engagement portion in the radial direction of the first axis.

Optionally, the external engagement portion includes an external engagement post, the internal engagement portion includes an internal engagement post, and on any plane perpendicular to the first axis, a cross-sectional area of the external engagement post is greater than a cross-sectional area of the internal engagement post.

Optionally, the transmission assembly includes a second-stage internal ring gear engaged with the second planet gear and including a plurality of bumps; and a lock including locking teeth that mate with the plurality of bumps, where the lock is capable of moving to at least a first position and a second position, where when the lock is at the first position, the locking teeth and the plurality of bumps are staggered in a circumferential direction of the first axis; and when the lock is at the second position, the locking teeth and the plurality of bumps are disengaged in the circumferential direction of the first axis.

Optionally, the transmission assembly includes a second-stage internal ring gear including a first state and a second state, where when the second-stage internal ring gear is in the first state, the second-stage internal ring gear is engaged with the second planet gears, and when the second-stage internal ring gear is in the second state, the second-stage internal ring gear is engaged with the second planet gears and the first planet carrier at the same time; and a lock including locking teeth that mate with the second-stage internal ring gear and cause the second-stage internal ring gear to stop rotating when the second-stage internal ring gear is in the first state.

Optionally, the second planet carrier is formed with an output portion connected to the output shaft.

Optionally, a gear ratio outputted by the first planetary gearset is greater than or equal to <NUM> and less than or equal to <NUM>.

Optionally, when the transmission assembly outputs the first gear ratio, a rotational speed of the output shaft is greater than or equal to <NUM> r/min and less than or equal to <NUM> r/min.

The present application provides a torque output tool. The torque output tool includes an output shaft, a motor, a transmission assembly, and a gearbox. The output shaft is used for outputting torque. The motor is used for driving the output shaft to rotate around a first axis. The transmission assembly is used for transmitting output of the motor to the output shaft. The gearbox is used for accommodating the transmission assembly. The transmission assembly includes a first planetary gearset and a second planetary gearset. The first planetary gearset includes first planet gears and a first planet carrier. The first planet gears are driven by the motor, and the first planet carrier is used for mounting the first planet gears. The second planetary gearset includes second planet gears and a second planet carrier. The second planet carrier is used for mounting the second planet gears. The transmission assembly is capable of being switched to a first state and a second state such that the transmission assembly outputs a first gear ratio or a second gear ratio separately, where the first gear ratio is greater than the second gear ratio. When the transmission assembly outputs the first gear ratio, a rotational speed of the output shaft is greater than or equal to <NUM> r/min and less than or equal to <NUM> r/min. A length of the gearbox in an axial direction of the first axis is configured to be greater than or equal to <NUM> and less than or equal to <NUM>.

Optionally, the motor includes a motor shaft that rotates around the first axis; the transmission assembly includes a sun gear fixedly connected to the motor shaft; a first planet gear of the first planet gears includes an external engagement portion that forms external engagement with the sun gear and an internal engagement portion fixedly connected to the external engagement portion.

Optionally, the transmission assembly includes a first-stage internal ring gear that forms internal engagement with the internal engagement portion, where the first-stage internal ring gear in a radial direction of the first axis at least partially overlaps with a projection of the internal engagement portion in the radial direction of the first axis.

Optionally, the motor includes a motor shaft that rotates around the first axis and a sun gear fixedly connected to the motor shaft; where the first planet gears are engaged with the sun gear; and the second planetary gearset includes external engagement portions that form external engagement with the first planet carrier and internal engagement portions fixedly connected to the external engagement portions.

Optionally, the transmission assembly includes a second-stage internal ring gear that forms internal engagement with the internal engagement portions, where the second-stage internal ring gear at least partially overlaps with the internal engagement portions in a radial direction of the first axis.

Optionally, a torque output device further includes a torque adjustment ring sleeved on a front end of the gearbox and capable of moving forward and backward on the gearbox; an elastic member support connected to the torque adjustment ring; and an elastic member disposed on the elastic member support; where the elastic member support is at least partially sleeved on the torque adjustment ring such that the elastic member support at least partially overlaps with the torque adjustment ring in a radial direction of the first axis.

Referring to <FIG> and <FIG>, a torque output tool <NUM> is used for outputting torque and includes a motor <NUM>, a housing <NUM>, a transmission assembly <NUM>, and an output shaft <NUM>. The housing <NUM> accommodates the motor <NUM> and the transmission assembly <NUM> and supports the output shaft <NUM>. The motor <NUM> is used for driving the output shaft <NUM> to rotate around a first axis <NUM>, and the transmission assembly <NUM> connects the motor <NUM> to the output shaft <NUM> to transmit output of the motor <NUM> to the output shaft <NUM>. The transmission assembly <NUM> has multiple states in which the output shaft <NUM> outputs different power and rotational speeds. A transmission state of the transmission assembly <NUM> is switched so that a torque magnitude and a rotational speed outputted by the output shaft <NUM> can be switched, thereby satisfying different operation requirements of a user.

The torque output tool <NUM> may be a tool such as an electric drill, an impact drill, and a screwdriver. In this example, an electric drill is used as an example. The torque output tool <NUM> further includes a collet device <NUM> for clamping a tool accessory such as a drill bit, where the collet device <NUM> is connected to the output shaft <NUM> to drive the tool accessory to perform output.

Referring to <FIG>, the housing <NUM> includes a head housing <NUM> and a grip <NUM>, and the motor <NUM> and the transmission assembly <NUM> are disposed in the head housing <NUM>. The grip <NUM> is connected to the head housing <NUM> and used for the user to hold. Optionally, the head housing <NUM> and the grip <NUM> are connected in an L shape or a T shape to be convenient for the user to hold and operate. The torque output tool <NUM> further includes a power supply device, where the power supply device may be a battery pack or a mains connector and is configured to be connected to the housing <NUM>. The torque output tool <NUM> further includes a gearbox <NUM> for accommodating the transmission assembly <NUM>, where the gearbox <NUM> is disposed in the housing <NUM> and connected to or integrally formed with the head housing <NUM>.

Referring to <FIG>, the transmission assembly <NUM> is a double-layer planetary gearset and includes a first planetary gearset <NUM> and a second planetary gearset <NUM>, where the first planetary gearset <NUM> includes first planet gears <NUM> and a first planet carrier <NUM>, and the first planet gears <NUM> are driven by the motor <NUM>. The first planet carrier <NUM> is used for mounting the first planet gears <NUM>. After the first planet gears <NUM> are mounted on the first planet carrier <NUM>, the first planet gears <NUM> can rotate relative to the first planet carrier <NUM>. The second planetary gearset <NUM> includes second planet gears <NUM> and a second planet carrier <NUM>. The second planet carrier <NUM> is used for mounting the second planet gears <NUM>. After the second planet gears <NUM> are mounted on the second planet carrier <NUM>, the second planet gears <NUM> can rotate relative to the second planet carrier <NUM>. The transmission assembly <NUM> decreases the rotational speed of the output shaft <NUM> through the first planetary gearset <NUM> and the second planetary gearset <NUM>.

The motor <NUM> includes a motor shaft <NUM> rotatable relative to the housing <NUM> around the first axis <NUM>, and the transmission assembly <NUM> includes a sun gear <NUM>, where the sun gear <NUM> is fixedly connected to the motor shaft <NUM> such that the sun gear <NUM> and the motor shaft <NUM> rotate synchronously. The first planetary gearset <NUM> is disposed closer to the motor shaft <NUM> than the output shaft <NUM>, multiple first planet gears <NUM> are provided and configured to be engaged with the sun gear <NUM>, and the motor <NUM> drives, through the sun gear <NUM>, the first planet gears <NUM> to rotate. The sun gear <NUM> and the first planet gears <NUM> form engagement teeth that transmit power. A diameter of an addendum circle of the sun gear <NUM> is configured to be less than a diameter of an addendum circle of the first planet gear <NUM> so that the number of engagement teeth of the first planet gear <NUM> is greater than the number of engagement teeth of the sun gear <NUM>.

The transmission assembly <NUM> can be switched to a first state and a second state such that the transmission assembly <NUM> outputs a first gear ratio or a second gear ratio separately, where the first gear ratio is less than the second gear ratio. In this manner, when the transmission assembly <NUM> is in the first state or the second state, the output shaft <NUM> is switched to a high-speed rotation mode or a low-speed rotation mode correspondingly to provide different output states.

The transmission assembly <NUM> includes a first-stage internal ring gear <NUM> that forms a front ring gear of the transmission assembly, and internal teeth are formed on an inner circumference of the first-stage internal ring gear <NUM>. The internal teeth of the first-stage internal ring gear <NUM> form engagement with the engagement teeth of the first planet gear <NUM>. The first-stage internal ring gear <NUM> is fixed by the gearbox <NUM> and cannot rotate relative to the gearbox <NUM>.

Referring to <FIG>, the first planet gear <NUM> includes an external engagement portion <NUM> and an internal engagement portion <NUM>, where the external engagement portion <NUM> includes an external engagement post <NUM> and external engagement teeth <NUM> formed in a circumferential direction of the external engagement post <NUM>, the first planet gear <NUM> forms external engagement with the sun gear <NUM> through the external engagement teeth <NUM>, the internal engagement portion <NUM> includes an internal engagement post <NUM> and internal engagement teeth <NUM> formed in a circumferential direction of the internal engagement post <NUM>, the first planet gear <NUM> forms internal engagement with the first-stage internal ring gear <NUM> through the internal engagement teeth <NUM>, and the first-stage internal ring gear <NUM> in a radial direction of the first axis <NUM> at least partially overlaps with a projection of the internal engagement portion <NUM> in the radial direction of the first axis <NUM>. The external engagement portion <NUM> and the internal engagement portion <NUM> are fixedly connected. Optionally, the external engagement post <NUM> and the internal engagement post <NUM> are integrally formed. The external engagement post <NUM> is closer to the motor <NUM> than the internal engagement post <NUM>, and the external engagement post <NUM> and the internal engagement post <NUM> are arranged concentrically, that is, axes of the external engagement post <NUM> and the internal engagement post <NUM> are disposed on the same straight line. On each plane perpendicular to the first axis <NUM>, a cross-sectional area of the external engagement post <NUM> is greater than a cross-sectional area of the internal engagement post <NUM>.

The first planet carrier <NUM> includes a transmission plate <NUM>, support brackets <NUM>, and a first output portion <NUM>. The support brackets <NUM> and the first output portion <NUM> are formed on two sides of the transmission plate <NUM> separately, and the support brackets <NUM> are inserted into internal engagement portions <NUM> and rotatably connected to the first planet gears <NUM> so that the internal engagement portions <NUM> can drive the first planet carrier <NUM> to rotate around the first axis <NUM> during operation. Engagement teeth are formed on circumferential sides of both the transmission plate <NUM> and the first output portion <NUM>, and the first output portion <NUM> is used for being engaged with the second planetary gearset <NUM>, thereby achieving the transmission connection between the first planetary gearset <NUM> and the second planetary gearset <NUM>.

When the motor <NUM> is started, the motor <NUM> transmits power to the sun gear <NUM>, and the sun gear <NUM> transmits the power to the external engagement portion <NUM> of the first planet gear <NUM>. Since the external engagement portion <NUM> and the internal engagement portion <NUM> are fixedly connected, the external engagement portion <NUM> and the internal engagement portion <NUM> rotate synchronously. The internal engagement portion <NUM> and the first-stage internal ring gear <NUM> form internal engagement. Since the first-stage internal ring gear <NUM> is fixed to the gearbox <NUM>, the internal engagement portions <NUM> rotate around the first axis <NUM> to drive the first planet carrier <NUM> to rotate, thereby transmitting the power to the first planet carrier <NUM>. The first-stage internal ring gear <NUM> in the radial direction of the first axis <NUM> at least partially overlaps with the projection of the internal engagement portion <NUM> in the radial direction of the first axis <NUM> and does not interfere with a projection of the external engagement portion <NUM> in the radial direction of the first axis <NUM>. In this manner, on the premise of the same diameter of the gearbox <NUM>, a diameter of an addendum circle of the external engagement portion <NUM> can be increased accordingly, and the number of the external engagement teeth <NUM> can be increased, thereby effectively increasing a gear ratio that can be provided by the first planetary gearset <NUM>. A diameter of an addendum circle of the internal engagement portion <NUM> is less than the diameter of the addendum circle of the external engagement portion <NUM> so that an inner diameter of the first-stage internal ring gear <NUM> can be correspondingly reduced, thereby increasing the gear ratio that can be outputted by the first planetary gearset <NUM>. Therefore, the torque output tool <NUM> provided in this example is not only reduced in dimension compared with a gearbox of a traditional three-layer planetary gearset but also reduced in dimension compared with a gearbox of a traditional double-layer planetary gearset so that the dimension of the whole machine is effectively reduced and the torque output tool <NUM> is portable. On the premise that only the double-layer planetary gearset is provided as a traditional structure, the transmission assembly <NUM> can provide a relatively high gear ratio and ensure the strength of gears and internal ring gears. The first planetary gearset <NUM> may provide a gear ratio greater than or equal to <NUM> and less than or equal to <NUM>, and a dimension L1 of the gearbox <NUM> along an axial direction of the first axis <NUM> may be reduced to be greater than or equal to <NUM> and less than or equal to <NUM>. In this manner, while the dimension of the torque output tool <NUM> is greatly reduced, a relatively high gear ratio is provided, thereby ensuring the performance and service life of the torque output tool <NUM>.

Referring to <FIG> and <FIG>, multiple second planet gears <NUM> are provided and form external engagement with the first output portion <NUM>, that is, the first output portion <NUM> of the first planetary gearset <NUM> forms the sun gear of the second planet gears <NUM>. The transmission assembly <NUM> further includes a second-stage internal ring gear <NUM>, and internal teeth are formed on an inner circumference of the second-stage internal ring gear <NUM>. The second-stage internal ring gear <NUM> and the second planet gears <NUM> are engaged. The second planet gears <NUM> are rotatably connected to the second planet carrier <NUM>. The second planet carrier <NUM> is formed with a second output portion <NUM> connected to the output shaft <NUM>. The output shaft <NUM> includes flat portions that mate with the second output portion <NUM>. Part of the output shaft <NUM> is interposed into the second output portion <NUM>, thereby achieving the synchronous rotation of the output shaft <NUM> and the second output portion <NUM>.

Referring to <FIG> and <FIG>, the second-stage internal ring gear <NUM> includes a first state and a second state. When the second-stage internal ring gear <NUM> is in the first state, the second-stage internal ring gear <NUM> is engaged with the second planet gears <NUM>. When the second-stage internal ring gear <NUM> is in the second state, the second-stage internal ring gear <NUM> is engaged with the second planet gears <NUM> and the first planet carrier <NUM> at the same time. The transmission assembly further includes a lock <NUM> for causing the second-stage internal ring gear <NUM> to stop rotating when the second-stage internal ring gear <NUM> is in the second state.

The torque output tool <NUM> further includes a toggle switch <NUM> and a link <NUM>. The toggle switch <NUM> is disposed on the housing <NUM> and used for switching the first state or the second state of the second-stage internal ring gear <NUM>. The link <NUM> penetrates through the gearbox <NUM> and connects the toggle switch <NUM> to the lock <NUM>. The link <NUM> may be a metal lead screw or may be a connecting structure extending from the second-stage internal ring gear <NUM>. The second-stage internal ring gear <NUM> may be pushed along the axial direction of the first axis <NUM> through the toggle switch <NUM> so that when the second-stage internal ring gear <NUM> is in the first state, the second-stage internal ring gear <NUM> is engaged with the second planet gears <NUM>, and when the second-stage internal ring gear <NUM> is in the second state, the second-stage internal ring gear <NUM> is engaged with the second planet gears <NUM> and the first planet carrier <NUM> at the same time. The second-stage internal ring gear <NUM> includes multiple bumps <NUM>, and the lock <NUM> includes locking teeth <NUM> that mate with the bumps <NUM>. When the second-stage internal ring gear <NUM> is pushed into the first state, the locking teeth <NUM> and the bumps <NUM> are staggered in a circumferential direction of the first axis <NUM>. At this time, the locking teeth <NUM> abut against the bumps <NUM> so as to limit the rotation of the second-stage internal ring gear <NUM>, that is, the second-stage internal ring gear <NUM> in the second state cannot rotate relative to the gearbox <NUM> around the first axis <NUM>.

When the second-stage internal ring gear <NUM> is in the first state, the second-stage internal ring gear <NUM> is engaged with only the second planet gears <NUM>, and the second-stage internal ring gear <NUM> cannot rotate relative to the gearbox <NUM>. In this case, the second planetary gearset <NUM> performs deceleration, and the transmission assembly <NUM> outputs the first gear ratio. When the second-stage internal ring gear <NUM> is in the second state, the second-stage internal ring gear <NUM> is engaged with the second planet gears <NUM> and the first planet carrier at the same time. At this time, the second-stage internal ring gear <NUM> is disengaged from the lock <NUM>, and the second-stage internal ring gear <NUM>, the first planet carrier <NUM> and the second planet gears <NUM> rotate at the same speed for output. In this case, the second planetary gearset <NUM> does not perform deceleration, and the transmission assembly <NUM> outputs the second gear ratio. Therefore, the second gear ratio is less than the first gear ratio. When the transmission assembly <NUM> is in the first state, the output shaft <NUM> rotates at a low speed and outputs relatively large torque. When the transmission assembly <NUM> is in the second state, the output shaft <NUM> rotates at a relatively high speed and outputs relatively small torque. Through the preceding principles, the transmission assembly <NUM> can output the first gear ratio or the second gear ratio separately through the toggle switch <NUM>, so as to switch the rotational speed of the output shaft <NUM>.

The lock <NUM> may be an annular body fixedly connected to the gearbox <NUM> or the housing <NUM>, and the locking teeth <NUM> are formed on the annular body and used for limiting the second-stage internal ring gear <NUM>. Optionally, the lock <NUM> may be integrally formed with the gearbox <NUM> or the housing <NUM>, and the lock <NUM> extending from the housing <NUM> or the gearbox <NUM> is used for limiting the second-stage internal ring gear <NUM>.

Referring to <FIG>, in an example, first planet gears <NUM> are engaged with a sun gear <NUM>, a second planet gear <NUM> includes an external engagement portion <NUM> and an internal engagement portion <NUM>, and the external engagement portion <NUM> forms external engagement with a first planet carrier <NUM>. The external engagement portion <NUM> and the internal engagement portion <NUM> are fixedly connected. A second-stage internal ring gear <NUM> forms internal engagement with the internal engagement portion <NUM>, and the second-stage internal ring gear <NUM> at least partially overlaps with the internal engagement portion <NUM> in a radial direction of a first axis <NUM>. The second-stage internal ring gear <NUM> is fixed to a gearbox <NUM> and cannot rotate relative to the gearbox <NUM>. The second-stage internal ring gear <NUM> and second planet gears <NUM> are engaged. The second planet gears <NUM> are rotatably connected to a second planet carrier <NUM>. The second planet carrier <NUM> is formed with a second output portion <NUM> connected to an output shaft <NUM>. The output shaft <NUM> includes flat portions that mate with the second output portion <NUM>. Part of the output shaft <NUM> is interposed into the second output portion <NUM>, thereby achieving the synchronous rotation of the output shaft <NUM> and the second output portion <NUM>.

A first-stage internal ring gear <NUM> includes a first state and a second state. When the first-stage internal ring gear <NUM> is in the first state, the first-stage internal ring gear <NUM> is engaged with the second planet gears <NUM>. When the first-stage internal ring gear <NUM> is in the second state, the first-stage internal ring gear <NUM> is engaged with the second planet gears <NUM> and the first planet carrier <NUM> at the same time. The second planet gear <NUM> further includes a lock <NUM> for causing the first-stage internal ring gear <NUM> to stop rotating when the first-stage internal ring gear <NUM> is in the second state.

Referring to <FIG>, the torque output tool <NUM> further includes a torque adjustment assembly <NUM> that includes a torque adjustment ring <NUM> sleeved on a front end of the gearbox <NUM>, for example, sleeved on the front of the gearbox <NUM>. The torque adjustment ring <NUM> can move forward and backward on the gearbox <NUM>. The torque adjustment ring <NUM> is moved so as to press against or loosen the second-stage internal ring gear <NUM> in the gearbox <NUM>, thereby achieving torque adjustment.

An external thread <NUM> is provided at the front end of the gearbox <NUM>, the external thread <NUM> is provided on a front housing <NUM> of the gearbox <NUM>, and an internal thread adapted to the external thread <NUM> is provided on an inner wall of the torque adjustment ring <NUM>. The internal thread mates with the external thread <NUM> so that the torque adjustment ring <NUM> is connected to the gearbox <NUM>. When the torque adjustment ring <NUM> is rotated, the torque adjustment ring <NUM> can move forward and backward on the gearbox <NUM> through threads, thereby achieving the torque adjustment of the torque output tool <NUM>.

The torque adjustment assembly <NUM> further includes an elastic member support <NUM> that is connected to the torque adjustment ring <NUM> and can move together with the torque adjustment ring <NUM>. An elastic member <NUM> is disposed on the elastic member support <NUM> and connected to a shift pin <NUM>, and the shift pin <NUM> abuts against the second-stage internal ring gear <NUM> to press against or loosen the second-stage internal ring gear <NUM>. As shown in <FIG>, the shift pin <NUM> penetrates through the housing <NUM> of the gearbox <NUM>, a rear end of the shift pin <NUM> abuts against a front end of the second-stage internal ring gear <NUM> so as to press against the second-stage internal ring gear <NUM>, a front end of the shift pin <NUM> abuts against the elastic member <NUM>, the elastic member <NUM> is disposed on the elastic member support <NUM>, and the elastic member support <NUM> is connected to the torque adjustment ring <NUM>. When the torque adjustment ring <NUM> moves forward and backward along the gearbox <NUM> under an external force, the torque adjustment ring <NUM> drives the elastic member support <NUM> to move forward and backward, so as to press against or loosen the elastic member <NUM>. The elastic member <NUM> further presses against or loosens the shift pin <NUM>, thereby switching a pressing force applied by the shift pin <NUM> to the second-stage internal ring gear <NUM>.

The elastic member support <NUM> is at least partially sleeved on the torque adjustment ring <NUM>, that is, a segment of the elastic member support <NUM> is overlaid on the torque adjustment ring <NUM> in the direction of the first axis <NUM> so that the elastic member support <NUM> can at least partially overlap with the torque adjustment ring <NUM> in the radial direction of the first axis <NUM>. The elastic member support <NUM> is nested on the torque adjustment ring <NUM>, which can reduce a dimension of the whole machine along the direction of the first axis <NUM>. In addition, the elastic member <NUM> is disposed in an axial projection of the torque adjustment ring <NUM> in the direction of the first axis <NUM> so that the elastic member <NUM> can be prevented from occupying a relatively large space in the radial direction, and a radial dimension of the whole machine can be reduced. In this manner, the torque output tool <NUM> is more portable and can be applied to more operation scenarios. A dimension of the torque adjustment assembly <NUM> is reduced and an overall length of the torque output tool <NUM> is reduced so that while the performance of the torque output tool <NUM> is ensured, an overall dimension of the torque output tool <NUM> can be greatly reduced.

The torque output tool <NUM> further includes a torque adjustment assembly <NUM> that includes a torque adjustment ring <NUM> sleeved on a front end of the gearbox <NUM>, for example, sleeved on the front of the gearbox <NUM>. The torque adjustment ring <NUM> can move forward and backward on the gearbox <NUM>. The torque adjustment ring <NUM> is moved so as to press against or loosen the second-stage internal ring gear <NUM> in the gearbox <NUM>, thereby achieving torque adjustment.

In the present application, as shown in <FIG>, the elastic member support <NUM> is at least partially sleeved on the torque adjustment ring <NUM>, that is, a segment of the elastic member support <NUM> is overlaid on the torque adjustment ring <NUM> in the direction of the first axis <NUM> so that the elastic member support <NUM> can at least partially overlap with the torque adjustment ring <NUM> in the radial direction of the first axis <NUM>. The elastic member support <NUM> is nested on the torque adjustment ring <NUM>, which can reduce a dimension of the whole machine along the direction of the first axis <NUM>. In addition, the elastic member <NUM> is disposed in an axial projection of the torque adjustment ring <NUM> in the direction of the first axis <NUM> so that the elastic member <NUM> can be prevented from occupying a relatively large space in the radial direction, and a radial dimension of the whole machine can be reduced. In this manner, the torque output tool <NUM> is more portable and can be applied to more operation scenarios. A dimension of the torque adjustment assembly <NUM> is reduced and an overall length of the torque output tool <NUM> is reduced so that while the performance of the torque output tool <NUM> is ensured, an overall dimension of the torque output tool <NUM> can be greatly reduced.

Referring to <FIG>, in another example of the present application, a second-stage internal ring gear 250a is engaged with second planet gears 221a, the second-stage internal ring gear 250a includes multiple bumps 251a, and a lock 260a include locking teeth 261a that mate with the bumps 251a. A link 170a connects the lock 260a to a toggle switch 160a, and the lock 260a can move to at least a first position and a second position. When the lock 260a is at the first position, the locking teeth 261a and the second internal ring gear are staggered in a circumferential direction of a first axis; and when the lock 260a is at the second position, the locking teeth 261a and the bumps 251a are disengaged in the circumferential direction of the first axis. When the lock 260a is at the first position, the locking teeth 261a abut against the bumps 251a so as to limit the rotation of the second-stage internal ring gear 250a, that is, the second-stage internal ring gear 250a cannot rotate relative to the gearbox around the first axis at this time. In this case, the second-stage planetary gearset performs deceleration, and a whole of a transmission assembly 200a outputs a first gear ratio. When the lock 260a is moved to the second position, the locking teeth 261a no longer abut against the bumps 251a so that the second-stage internal ring gear 250a can rotate relative to the gearbox, the second-stage internal ring gear 250a and the second planet gears 221a rotate synchronously, and the second-stage planetary gearset does not perform deceleration. In this case, the transmission assembly 200a outputs a second gear ratio as a whole, and the first gear ratio is greater than the second gear ratio.

Referring to <FIG> and <FIG>, <FIG> and <FIG> show a torque output tool 100b according to a second example of the present application. In the second example of the present application, a transmission assembly 200b of the torque output tool 100b is also a double-layer planetary gearset. Referring to <FIG> and <FIG>, the transmission assembly 200b includes a first planetary gearset 210b and a second planetary gearset 220b, where the first planetary gearset 210b includes first planet gears 211b and a first planet carrier 212b, and the second planetary gearset 220b includes second planet gears 221b and a second planet carrier 222b. The transmission assembly 200b includes a sun gear 230b, where the sun gear 230b is connected to a motor 110b and driven to rotate by the motor 110b. The first planet gears 211b are configured to be engaged with the sun gear 230b.

Referring to <FIG>, the transmission assembly 200b further includes a first-stage internal ring gear 240b fixed in a housing assembly 120b and engaged with the first planet gears 211b. Multiple first planet gears 211b are provided and configured to be engaged with the sun gear 230b, and the motor 110b drives, through the sun gear 230b, the first planet gears 211b to rotate. The sun gear 230b and the first planet gears 211b form engagement teeth that transmit power. A diameter of an addendum circle of the sun gear 230b is configured to be less than a diameter of an addendum circle of the first planet gear 211b so that the number of engagement teeth of the first planet gear 211b is greater than the number of engagement teeth of the sun gear 230b.

The first planet carrier 212b includes a transmission plate 2121b, support brackets 2122b, and a first output portion 2123b. The support brackets 2122b and the first output portion 2123b are formed on two sides of the transmission plate 2121b separately, and the support brackets 2122b are inserted into the first planet gears 211b and rotatably connected to the first planet gears 211b so that the first planet gears 211b can drive the first planet carrier to rotate around a first axis 101b during operation. Engagement teeth are formed on circumferential sides of both the transmission plate 2121b and the first output portion 2123b, and the first output portion 2123b is used for being engaged with the second planetary gearset 220b, thereby achieving the transmission connection between the first planetary gearset 210b and the second planetary gearset 220b.

Multiple second planet gears 221b are provided and form external engagement with the first output portion 2123b, that is, the first output portion 2123b of the first planetary gearset 210b forms the sun gear of the second planet gears 221b. The transmission assembly 200b further includes a second-stage internal ring gear 250b, and internal teeth are formed on an inner circumference of the second-stage internal ring gear 250b. The second-stage internal ring gear 250b and the second planet gears 221b are engaged. The second planet gears 221b are rotatably connected to the second planet carrier 222b. The second planet carrier 222b is formed with a second output portion 2221b connected to an output shaft 140b. The output shaft 140b includes flat portions that mate with the second output portion 2221b. Part of the output shaft 140b is interposed into the second output portion 2221b, thereby achieving the synchronous rotation of the output shaft 140b and the second output portion 2221b.

The second-stage internal ring gear 250b is engaged with the second planet gears 221b, the second-stage internal ring gear 250b includes multiple bumps 251b, and a lock 260b includes locking teeth 261b that mate with the bumps 251b. A link 170b connects the lock 260b to a toggle switch 160b, and the lock 260b can move to at least a first position and a second position. When the lock 260b is at the first position, the locking teeth 261b and the second internal ring gear are staggered in a circumferential direction of the first axis 101b; and when the lock 260b is at the second position, the locking teeth 261b and the bumps 251b are disengaged in the circumferential direction of the first axis 101b. When the lock 260b is at the first position, the locking teeth 261b abut against the bumps 251b so as to limit the rotation of the second-stage internal ring gear 250b, that is, the second-stage internal ring gear 250b cannot rotate relative to a gearbox 150b around the first axis 101b at this time. In this case, the second-stage planetary gearset performs deceleration, and the transmission assembly 200b outputs a first gear ratio as a whole. When the lock 260b is moved to the second position, the locking teeth 261b no longer abut against the bumps 251b so that the second-stage internal ring gear 250b can rotate relative to the gearbox 150b, the second-stage internal ring gear 250b and the second planet gears 221b rotate synchronously, and the second-stage planetary gearset does not perform deceleration. In this case, the transmission assembly 200b outputs a second gear ratio as a whole, and the first gear ratio is greater than the second gear ratio.

The lock 260b may include an annular body provided with the locking teeth 261b. The lock 260b is formed with a mating portion that mates with the gearbox 150b so that the housing 120b mates with the mating portion of the lock 260b so as to limit the rotation of the lock 260b relative to the housing 120b, and the lock 260b is fixed to the gearbox 150b and can move to the first position and the second position relative to the gearbox 150b.

Optionally, the lock 260b is fixed by the housing 120b and directly formed with the mating portion that mates with the housing 120b so that the housing 120b mates with the mating portion of the lock 260b so as to limit the rotation of the lock 260b relative to the housing 120b, and the lock 260b can move to the first position or the second position relative to the housing 120b along an axial direction of the first axis 101b. The housing 120b is provided with a through hole for part of the lock 260b to penetrate through the housing 120b so that the user can toggle the lock 260b to switch the first position or the second position where the lock 260b is located.

In the second example, the provided transmission assembly 200b completes the transmission of power through the double-layer planetary gearset so that a dimension of the gearbox 150b can be effectively reduced, and a position of the lock 260b is switched so as to switch a transmission coefficient, which is stable and reliable and can prolong the service life of the transmission assembly 200b. However, a relatively high gear ratio cannot be provided only through the double-layer planetary gearset provided in this example, so it cannot be ensured that the output shaft 140b can output sufficient torque. To make up for an insufficient deceleration capability of planet gears in two layers, in this example, a specific motor 110b is provided to mate with the transmission assembly 200b, so as to ensure the decelerated transmission of the motor 110b. Thus, the torque outputted by the output shaft 140b can satisfy operation requirements of the torque output tool 100b.

The motor 110b includes a stator assembly <NUM> and a rotor assembly <NUM>, where the stator assembly <NUM> includes a stator bracket <NUM> and stator windings <NUM>, and the rotor assembly <NUM> includes a rotor sleeve <NUM> and permanent magnets <NUM>. Slots for fixing the permanent magnets <NUM> are formed on the rotor sleeve <NUM>. The permanent magnets <NUM> are embedded into the slots and mounted on the rotor sleeve <NUM>. The stator windings <NUM> are configured to be wound onto the stator bracket <NUM>. The rotor assembly <NUM> is configured to be sleeved outside the stator assembly <NUM> and rotatable relative to the stator assembly <NUM>. After the motor 110b is energized, the rotor assembly <NUM> rotates relative to the stator assembly <NUM>, and the rotor assembly <NUM> includes a motor shaft 111b connected to the rotor sleeve <NUM> so that when the motor 110b is in operation, the motor shaft 111b rotates around the first axis 101b to drive the output shaft 140b.

In this example, multiple permanent magnets <NUM> are provided, and the number of poles formed by the permanent magnets <NUM> is configured to be not less than four pairs, so as to relatively adjust an output rotational speed of the motor 110b. The output rotational speed of the motor 110b is configured to be greater than or equal to <NUM> r/min and less than or equal to <NUM> r/min, so that the output rotational speed of the motor 110b matches the transmission capability of the transmission assembly 200b provided in this example, so that the torque output tool 100b has a reasonable output rotational speed and reasonable torque, and can reduce the size of the head housing 121b, and the strength of the transmission assembly 200b, so that the whole machine is easy to operate and prolong its life. Optionally, the transmission assembly 200b in the first example can cooperate with the motor in this example, so as to reduce the transmission ratio requirement of the transmission assembly 200b, thereby reducing the size of the transmission assembly 200b.

Claim 1:
A torque output tool (<NUM>, 100b), comprising:
an output shaft (<NUM>) for outputting torque;
a motor (<NUM>) for driving the output shaft to rotate around a first axis (<NUM>);
a housing (<NUM>) for supporting the motor;
a transmission assembly (<NUM>) for transmitting output of the motor to the output shaft; and
a gearbox (<NUM>) for accommodating at least a portion of the transmission assembly;
wherein the transmission assembly comprises:
a first planetary gearset (<NUM>) comprising first planet gears (<NUM>) and a first planet carrier (<NUM>), wherein the first planet gears are driven by the motor, and the first planet carrier is used for mounting the first planet gears; and
a second planetary gearset (<NUM>) comprising second planet gears (<NUM>) and a second planet carrier (<NUM>), wherein the second planet carrier is used for mounting the second planet gears;
wherein the transmission assembly is capable of being switched to a first state and a second state such that the transmission assembly outputs a first gear ratio or a second gear ratio separately, wherein the first gear ratio is greater than the second gear ratio;
wherein the motor comprises:
a motor shaft (<NUM>) that rotates around the first axis;
wherein the transmission assembly comprises:
a sun gear (<NUM>) fixedly connected to the motor shaft;
wherein each of the first planet gears comprises:
an external engagement portion (<NUM>) that forms external engagement with the sun gear; and
an internal engagement portion (<NUM>) fixedly connected to the external engagement portion; characterized in that
a length of the gearbox in an axial direction of the first axis is greater than or equal to <NUM> and less than or equal to <NUM>.