Patent ID: 12201057

DETAILED DESCRIPTION

A grass trimmer400in a first example shown inFIG.1is used for trimming lawns. Specifically, a user may operate the grass trimmer400to cut grass on the lawn or trim grass around shrubs or buildings. The grass trimmer400is installed with a grass trimmer rope40, and the grass trimmer rope40rotates at a high speed so that the grass is cut.

The grass trimmer400includes a front end device400a, a connecting rod assembly41, and a rear end device400b. The front end device400ais disposed at a front end of the connecting rod assembly41, and the rear end device400bis disposed at a rear end of the connecting rod assembly41. The connecting rod assembly41includes a connecting rod411and an auxiliary handle412. The connecting rod411is configured to connect the front end device400a, the rear end device400b, and the auxiliary handle412, and the connecting rod411basically extends along a direction of a first straight line401. In other examples, the connecting rod411may also extend along a curve. The auxiliary handle412is used for the user to hold in an auxiliary manner, and a position of the auxiliary handle412on the connecting rod411may be adjusted along the direction of the first straight line401. A direction along the first straight line401toward the front end device400ais defined as the front, and a direction along the first straight line401toward the rear end device400bis defined as the rear.

The rear end device400bincludes a main handle491, a rear housing492, and a circuit board assembly disposed in the rear housing492. The main handle491is for the user to hold. When the user operates the grass trimmer400, the main handle491and the auxiliary handle412may be respectively held by two hands so that the grass trimmer400is operated more stably. The main handle491is further provided with an operation switch491afor activating and powering on the grass trimmer400. After powered on, the grass trimmer400can drive the grass trimmer rope40to rotate at a high speed so as to cut the grass. The rear housing492is integrally formed with the main handle491. In other examples, the rear housing492may also be provided separately from the main handle491. The rear housing492is further formed with a joint portion492a, the joint portion492ais configured to be connected to an energy device, the energy device is a battery pack, and the battery pack is configured to supply a power source to the grass trimmer400. In other examples, the joint portion492amay also be connected to a cable, and the cable may be connected to a mains electricity grid. In other examples, the joint portion492amay also be connected to other energy devices. For example, the joint portion492amay be provided with a fuel tank, and the fuel in the fuel tank may supply power to the grass trimmer400.

As shown inFIGS.1and2, the front end device400aincludes a grass trimmer head50and a drive device60, and the grass trimmer head50is used for installing the grass trimmer rope40so as to drive the grass trimmer rope40to rotate at a high speed. The drive device60is configured to drive the grass trimmer head50to rotate.

The front end device400afurther includes a shield42surrounding at least part of the drive device60or the grass trimmer head50. The shield42is configured to prevent grass clippings from being splashed on the user. The grass trimmer head50is used for installing the grass trimmer rope40. As shown inFIGS.2to6, the grass trimmer head50includes a head housing51and a spool52, the spool52is used for the grass trimmer rope40to be wound around, and the head housing51is used for accommodating at least part of the spool52. A winding portion521is formed on the spool52, two threading elements53are connected to the head housing51, and two ends of the grass trimmer rope40pass through threading holes531on the threading elements53, respectively. A part of the grass trimmer rope40located in the head housing51is wound around the winding portion521. When the grass trimmer head50rotates at a high speed, the spool52and the head housing51drive the grass trimmer rope40to rotate at a high speed, and the rotating grass trimmer rope40can cut the grass.

In this example, the head housing51includes an upper housing511and a lower housing512, and the spool52is disposed between the upper housing511and the lower housing512. The upper housing511is further provided with a fan514. When the grass trimmer head50rotates, the head housing51drives the fan514to rotate, and the rotating fan514can generate a flowing airflow. The airflow can not only dissipate heat from the drive device60, but also flow in a direction away from the grass trimmer head50so as to prevent the front end device400afrom being entangled with grass clippings.

The drive device60is disposed on an upper side of the grass trimmer head50and configured to drive the grass trimmer head50to rotate. In this example, the drive device60is connected to the spool52, the drive device60drives the spool52to rotate about a first axis402, and a transmission mechanism is disposed between the spool52and the head housing51. In this example, the transmission mechanism includes a first driving portion522disposed on the spool52and a first mating portion513disposed on the head housing51. When the drive device60drives the spool52to rotate about the first axis402, the first driving portion522mates with the first mating portion513to drive the head housing51to rotate together with the spool52around the first axis402so that the grass trimmer400is in a grass trimming mode. In other examples, the drive device60may also be connected to the head housing51, the drive device60drives the head housing51to rotate, and through the first mating portion513, the head housing51drives the spool52to rotate together. In this example, when the grass trimmer400is in the grass trimming mode, the drive device60drives the grass trimmer head50to rotate about the first axis402in a first rotation direction403. As shown inFIG.1, the first rotation direction403may be a clockwise direction when viewed from top to bottom. It is to be understood that in other examples, the first rotation direction may also be a counterclockwise direction when viewed from top to bottom.

The front end device400afurther includes an operating device70, the operating device70is connected to the drive device60, and the operating device70includes an operating member71for the user to operate.

The grass trimmer400further has a winding mode. When the grass trimmer400is in the winding mode, the user operates the operating member71to make the operating member71move. At this time, movement of the operating member71is transmitted to the spool52or the head housing51through the drive device60so as to generate relative movement that is between the spool52and the head housing51and through which the grass trimmer rope40is wound around the spool52. Specifically, when the grass trimmer rope40is used up, the user needs to install a new grass trimmer rope40on the grass trimmer head50. At this time, the user may pass the grass trimmer rope40through the threading holes531to make a part of the grass trimmer rope40located in the head housing51, and then the user operates the operating member71. The movement of the operating member71is transmitted to the spool52through the drive device60so as to drive the spool52to rotate about the first axis402in a second rotation direction404, the spool52rotates relative to the head housing51, and the rotating spool52winds the grass trimmer rope40around the winding portion521. The second rotation direction404is opposite to the first rotation direction403. For example, the first rotation direction403is a clockwise direction, and the second rotation direction404is a counterclockwise direction. In this example, the operating member71moves to drive the spool52to rotate relative to the head housing51so that the user can wind the grass trimmer rope40around the spool52with less effort. On one hand, when winding the grass trimmer rope40, the user does not need to disassemble the spool52from the head housing51so that a winding effect is higher. On the other hand, the operation switch491ainstalled on the main handle491does not need to be activated, that is, when the grass trimmer400is in the winding mode, the grass trimmer400does not need to consume the power of the energy device, and the battery pack does not need to output power at this time, thereby saving energy. Furthermore, the grass trimmer400is configured not to be activated, and only through mechanical movement of the operating device70, the movement may be mechanically transmitted to the spool52through the drive device60, so as to ensure the reliability of the winding, and no winding failure occurs. In addition, the movement of the operating member71is transmitted to the spool52through the drive device60without additionally disposing a transmission device for power transmission, which can further reduce a dimension of the grass trimmer400and reduce the manufacturing cost of the grass trimmer400.

As shown inFIG.5, the first driving portion522includes a driving surface522aand an inclined surface522b. When the spool52rotates along the first rotation direction403, the driving surface522ais in contact with the first mating portion513so as to drive the head housing51to rotate with the spool52, and the grass trimmer400is in the grass trimming mode. When the spool52rotates along the second rotation direction404, the inclined surface522bof the spool52is in contact with the first mating portion513, the inclined surface522bcannot drive the head housing51to rotate with the spool52, and the inclined surface522bpasses over the first mating portion513so that the spool52can rotate relative to the head housing51along the second rotation direction404, and the grass trimmer400is in the winding mode at this time.

The grass trimmer400further includes a limiter54configured to restrict rotation of the head housing51along the second rotation direction404, the limiter54is a one-way bearing connected to the upper housing511, and the one-way bearing allows the head housing51to rotate along the first rotation direction403, but the one-way bearing does not allow the head housing51to rotate along the second rotation direction404. In this manner, when the spool52rotates along the first rotation direction403, the one-way bearing does not restrict the rotation of the head housing51, and the head housing51can rotate together with the spool52. When the spool52rotates along the second rotation direction404, the one-way bearing restricts the rotation of the head housing51along the second rotation direction404, and the spool52cannot drive the head housing51to rotate together. At this time, the spool52moves relative to the head housing51, and thus the grass trimmer rope40is wound around the spool52. In other examples, the limiter54may also be another limiting device with two states. In one state, the limiter54allows the head housing51to rotate, and in the other state, the limiter54restricts the rotation of the head housing51.

In this example, the drive device60includes a housing61and a motor disposed in the housing61, and the motor is specifically an electric motor62. The battery pack can supply power to the electric motor62, and the circuit board assembly is electrically connected to the electric motor62so as to control the electric motor62. The operation switch491ais configured to activate the electric motor62. When the grass needs to be cut, the user presses the operation switch491a, the operation switch491apowers on the electric motor62, and the electric motor62drives the spool52to rotate about the first axis402along the first rotation direction403. At this time, the grass trimmer head50rotates about the first axis402at a high speed, and the grass trimmer400is in the grass trimming mode. When the grass trimmer rope40needs to be wound, the user operates the operating member71, and the movement of the operating member71is mechanically transmitted to the spool52through the electric motor62so as to drive the spool52to rotate about the first axis402along the second rotation direction404so that the spool52moves relative to the head housing51, and the grass trimmer400is in the winding mode. When the grass trimmer400is in the winding mode, the operation switch491ais not operated, the electric motor62is not powered on, and only the electric motor62mechanically transmits the movement of the operating member71to the spool52, thereby reducing the failure possibility of the winding mode and reducing the power consumed by the electric motor62.

The electric motor62includes a motor shaft621, the motor shaft621extends along the first axis402, the motor shaft621can rotate about the first axis402, and the motor shaft621is connected to the spool52. In other examples, the motor shaft621may also be connected to the head housing51. In other examples, the motor shaft621may also be configured to rotate about an axis parallel to the first axis402. In other examples, the motor shaft621may also be configured to rotate about an axis inclined relative to the first axis402.

The housing61accommodates at least part of the electric motor62, the grass trimmer head50is disposed outside the housing61, and the motor shaft621extends from an inside of the housing61to an outside of the housing61and into the grass trimmer head50. The housing61is further formed with a connecting hole611into which the connecting rod411is inserted to be connected to the housing61so that the front end device400ais connected to a front end of the connecting rod411. The other end of the connecting rod411is inserted into the main handle491and connected to the rear end device400b.

The operating device70is connected to the housing61, and the operating member71is connected to an outer wall of the housing61so that the operating member71is located on the upper side of the grass trimmer head50, which is convenient for the user to operate. The operating member71specifically includes an operating portion711for the user to operate, and the operating portion711is disposed on the upper side of the grass trimmer head50. In this manner, when the user operates the operating member71, the user's hands can be kept away from the grass trimmer head50and not touch the grass trimmer head50so that the hands are not soiled and the subsequent grass trimming operation is not affected. In addition, the operating member71is disposed on the upper side of the grass trimmer head50so that the operating member71can be prevented from being entangled with grass clippings and the operating member71can be prevented from being stained with soil.

The front end device400afurther includes a clutch device65disposed between the operating device70and the drive device60. In this example, the clutch device65may connect the operating member71to the motor shaft621. The clutch device65is disposed at an end of the motor62away from the grass trimmer head50. As shown inFIGS.8and9, the clutch device65has a first state and a second state. In the case where the clutch device65is in the first state, the movement of the operating member71is transmitted to the drive device60through the clutch device65, and the grass trimmer400enters the winding mode. In the case where the clutch device65is in the second state, the clutch device65disconnects power transmission between the operating member71and the drive device60, and the grass trimmer400exits the winding mode and enters the grass trimming mode.

When the clutch device65is in the first state, the clutch device65connects the operating device70to the motor shaft621, and the movement of the operating member71may be transmitted to the spool52through the motor shaft621at this time. When the clutch device65is in the second state, the clutch device65disconnects power transmission between the operating device70and the motor shaft621, and the movement of the operating member71cannot be transmitted to the motor shaft621through the clutch device65at this time.

In fact, the operating member71may move to a first position and a second position relative to the housing61. When the operating member71is at the first position, the operating member71drives the clutch device65to switch to the first state. When the operating member71moves to the second position, the operating member71drives the clutch device65to switch to the second state. That is, the first position of the operating member71corresponds to the first state of the clutch device65, and the second position of the operating member71corresponds to the second state of the clutch device65.

As shown inFIGS.8and9, when the user needs to wind the rope, the operating member71may move from the second position to the first position. At this time, the operating member71drives the clutch device65to switch from the second state to the first state. The clutch device65connects the operating member71to the motor shaft621and can achieve power transmission between the operating member71and the motor shaft621, and the operating member71may mechanically drive the motor shaft621to rotate. At this time, the user holds the operating member71and rotates the operating member71about the first axis402, the clutch device65also rotates about the first axis402along with the operating member71, and then the clutch device65drives the motor shaft621to rotate about the first axis402, and the rotating motor shaft621drives the spool52to rotate relative to the head housing51along the second rotation direction404, thereby winding the grass trimmer rope40around the spool52.

After the grass trimmer rope40is wound, the user needs to use the grass trimmer400to trim the grass. At this time, the user releases the operating member71or drives the operating member71to be reset to the second position, the clutch device65is also reset to the second state, and the clutch device65disconnects the power transmission between the operating member71and the motor shaft621. At this time, the user turns on the operation switch491a, the electric motor62is powered on and starts to operate, the motor shaft621rotates, and the rotating motor shaft621drives the grass trimmer head50to rotate at a high speed so as to trim the grass. At this time, the grass trimmer400is in the grass trimming mode. When the clutch device65is at the second position and the motor shaft621rotates, the clutch device65does not transmit movement of the motor shaft621to the operating member71, so the operating member71remains stationary at this time.

The clutch device65is provided so that the grass trimmer head50can be switched between the grass trimming mode and the winding mode. When the grass trimmer400trims the grass, the operating member71does not move; and when the rope in the grass trimmer400is wound, the electric motor62is not powered on. Therefore, the grass trimming mode and the winding mode of the grass trimmer400do not interfere with each other.

As shown inFIGS.5to9, the operating member71may rotate relative to the housing61around a second axis405. When rotating relative to the housing61around the second axis405, the operating member71may rotate to the second position shown inFIG.2, and the operating member71may also rotate relative to the housing61around the second axis405to the first position shown inFIG.7. As shown inFIGS.2and8, when the operating member71rotates to the second position, the clutch device65is reset to the second state, and the clutch device65disconnects power transmission between the operating member71and the electric motor62. As shown inFIGS.7and9, when the operating member71rotates to the first position, the operating member71drives the clutch device65to switch to the first state, and the clutch device65connects the operating member71to the electric motor62. At this time, the clutch device65may achieve power transmission between the operating member71and the motor shaft621.

The second axis405is perpendicular to the first axis402. The housing61is provided with a mount612, and the operating member71is installed to the mount612and may rotate relative to the mount612around the second axis405.

The housing61includes a surrounding portion613and a top portion614, the surrounding portion613surrounds the electric motor62, the top portion614is disposed on an upper side of the electric motor62, and the top portion614is connected to an upper side of the surrounding portion613. The mount612for installing the operating member71is disposed on the top portion614so that the operating member71is connected to the top portion614. The operating member71may rotate relative to the top portion614around the second axis405to move to the first position and the second position. The operating member71may also drive the mount612to rotate relative to the surrounding portion613about the first axis402. In this example, the mount612is fixedly connected to the top portion614, the mount612rotates in sync with the top portion614, and a whole formed by the operating member71, the mount612, and the top portion614may rotate relative to the surrounding portion613about the first axis402. In other examples, the mount may also be rotatably connected to the top portion. When the operating member71moves to the first position, the user operates the operating member71to rotate the operating member71about the first axis402, and at this time, the operating member71drives the mount612and the top portion614to rotate relative to the surrounding portion613around the first axis402. The clutch device65rotates in sync with the mount612. When the operating member71is at the first position, the clutch device65is connected to the motor shaft621, the operating member71drives the mount612to rotate about the first axis402, and the clutch device65also rotates about the first axis402along with the mount612so that the clutch device65drives the motor shaft621to rotate about the first axis402. At this time, the clutch device65transmits rotation of the operating member71to the motor shaft621so that the spool52may rotate relative to the head housing51, thereby achieving winding.

The clutch device65specifically includes a clutch element651and a reset element652. The clutch element651may move to a transmission position and a non-transmission position. The reset element652is a spring that biases the clutch element651to move toward the non-transmission position. When the operating member71is operated by the user to move from the second position to the first position, the operating member71drives the clutch element651to move from the non-transmission position to the transmission position, and the clutch device65switches from the second state to the first state. That is, when the clutch element651is at the transmission position, the clutch device65is in the first state; and when the clutch element651is in the non-transmission position, the clutch device65is in the second state. Specifically, the operating member71is formed with a driving portion712which is a cam portion. When the operating member71moves from the second position to the first position, the driving portion712drives the clutch element651to move along the first axis402toward the motor shaft621so that the clutch element651is finally connected to the motor shaft621, and the clutch device65switches to the first state at this time. When the clutch element651moves to the non-transmission position, the clutch element651is disengaged from the motor shaft621, and the clutch device65switches to the second state. A position of the mount612remains fixed along the first axis402. When the operating member71moves relative to the mount612around the second axis405from the second position to the first position, the driving portion712is to be in contact with the clutch element651and then drives the clutch element651to slide relative to the mount612. The mount612rotates in sync with the clutch element651, the mount612is formed with a mounting groove612a, and the clutch element651includes an arm651awhich can be inserted into the mounting groove612a. The mounting groove612amates with the arm651a, the mounting groove612arotates in sync with the arm651aabout the first axis402, and the mounting groove612aalso allows the arm651ato slide along a direction of the first axis402.

The reset element652generates a biasing press that drives the clutch element651to move toward the non-transmission position. When the operating member71is reset from the first position to the second position, the operating member71allows the clutch element651to be reset to the non-transmission position. At this time, the reset element652drives the clutch element651to be reset to the non-transmission position so that it can be ensured that when the user does not operate the operating member71, the clutch element651remains at the non-transmission position and does not affect the grass trimming of the grass trimmer400. Specifically, the reset element652is a spring, the spring abuts against the clutch element651, and the biasing press generated by the spring biases the clutch element651to move in a direction away from the motor shaft621.

The clutch element651is formed with a first transmission portion651b, the motor shaft621is formed with or connected to a second transmission portion621a, and the first transmission portion651band the second transmission portion621acan mate with each other. Specifically, the clutch element651is formed with a transmission hole, a hole wall of the transmission hole is formed with the first transmission portion651b, and the first transmission portion651bis first meshing teeth. The motor shaft621is fixedly connected to a driving wheel, the driving wheel is formed with the second transmission portion621a, and the second transmission portion621ais second meshing teeth. When the clutch element651moves to the transmission position, the driving wheel extends into the transmission hole, the first transmission portion651bis meshed with the second transmission portion621a, and the clutch element651can drive the motor shaft621to rotate. When the clutch element651moves to the non-transmission position, the first transmission portion651bis disengaged from the second transmission portion621a.

In this example, the operating member71is at least partially disposed on an upper side of the drive device60so that the user operates more conveniently, and when the user winds the rope, the user's hands can be kept away from the grass trimmer head50and the arm651acan be prevented from being soiled.

Specifically, the operating member71further includes a connecting portion713used for connecting the operating member71to the mount612. The operating member71is disposed at least partially on the upper side of the grass trimmer head50. Along the direction of the first axis402, a distance L1between the operating member71and a lower end surface of the grass trimmer head50is greater than or equal to 30 mm and less than or equal to 220 mm. In this manner, when the user operates the operating portion711, a certain distance exists between the user's hands and the lower end surface of the grass trimmer head50so that the user's hands do not touch the ground or the lower end surface of the grass trimmer head50. When the grass trimmer400switches from the grass trimming mode to the winding mode, the position of the operating portion711changes.

A part other than the operating member71of the grass trimmer400is defined as a main body406. The main body406includes the rear end device400b, the connecting rod assembly41, the auxiliary handle412, the drive device60, and the grass trimmer head50. In this example, the operating member71is fixedly installed to the main body406. Specifically, the operating member71is installed to the housing61. In this manner, even when the grass trimmer400is in the grass trimming mode, the operating member71is still installed to the main body406. Therefore, regardless of whether the grass trimmer400is in the winding mode or the grass trimming mode, the operating member71is installed on the housing61, and the operating member71will never be disengaged from the main body406so that the operating member71can be prevented from being lost.

In this example, the operating member71is fixedly installed to the mount612. In other examples, the operating member may also be detachably installed to the mount. Alternatively, in other examples, the operating member may also be non-detachably installed to the mount.

In other examples, when the operating member71is detachably installed to the mount612, other parts of the main body406may further be provided with a receiving groove capable of receiving the operating member71. When the grass trimmer400is in the winding mode, the operating member71is installed to the mount612. When the grass trimmer400is in the grass trimming mode, the operating member71is installed to the receiving groove. In this manner, even when the grass trimmer400is in the grass trimming mode, the operating member71may still be installed to the main body406so that the operating member71can be prevented from being lost.

As shown inFIG.2, the housing61is further formed with an accommodation groove615, and when the operating member71is at the second position, the operating portion711is inserted into the accommodation groove615. When the user does not operate the operating member71, the accommodation groove615can restrict the operating member71from being disengaged from the accommodation groove615so that the operating member71can be prevented from being shaken.

As shown inFIGS.7and8, the operating portion711further includes a roller711a, and the roller711ais rotatably connected to the connecting portion713so that the user may operate the operating member71by operating the roller711a, thereby making the user's operation more labor-saving.

In this example, when the grass trimmer400is in the winding mode, the user rotates the operating member71about the first axis402, and a distance L2between the operating portion711and the first axis402is greater than or equal to 40 mm and less than or equal to 100 mm. In this manner, the user can save efforts when rotating the operating member71, and at the same time, the operating member71can be prevented from being too large to affect a dimension of the front end device400a.

As shown inFIG.10, the grass trimmer700in a second example includes a connecting rod701, a rear end device, and a front end device73. The front end device73includes a housing731, an electric motor732, a drive device733, and a grass trimmer head734. The housing731accommodates the drive device733and the electric motor732, the drive device733is disposed between the electric motor732and the grass trimmer head734to connect the electric motor732to the grass trimmer head734, and the drive device733transmits power outputted by the electric motor732to the grass trimmer head734. The grass trimmer head734includes a spool734aand a head housing734b, and the electric motor732drives the spool734aor the head housing734bthrough the drive device733so that the grass trimmer head734rotates about the first axis. The front end device73further includes an operating device735configured to be connected to the drive device733. The operating device735includes an operating member735aconnectable to the drive device733, and movement of the operating member735ais transmitted to the spool734aor the head housing734bthrough the drive device733without the need to transmit power to the spool734aor the head housing734bthrough the electric motor732. When the grass trimmer700is in the winding mode, the operating member735arotates to drive the drive device733to rotate, and the drive device733drives the spool734aor the head housing734bto rotate so as to generate relative movement between the spool734aand the head housing734b. When the grass trimmer700is in the grass trimming mode, the operating member735ais disengaged from the drive device733, the electric motor732drives the drive device733to rotate, and the drive device733drives the spool734aor the head housing734bto drive the grass trimmer head734to rotate.

FIG.11is a front end device100aof a grass trimmer according to a third example. The grass trimmer in the third example has the same rear end device and connecting rod as the grass trimmer in the first example. The front end device100ain the third example is the same as the front end device400ain the first example. A function of a drive device20in the third example is basically the same as the drive device in the first example, and a difference lies in a specific structure of the drive device20being different from that in the first example. An operating device30in the third example may achieve basically the same function as the operating device70in the first example, and a difference is that a specific structure of the operating device30in the third example is different from a specific structure of the operating device70in the first example.

As shown inFIG.11, the front end device100aincludes a grass trimmer head10and the drive device20. The grass trimmer head10is configured to trim the grass, and the drive device20is configured to drive the grass trimmer head10to rotate about a rotation axis101.

As shown inFIGS.11to16, the drive device20includes a motor21, a motor housing212, and a transmission assembly22. The motor21is configured to drive the grass trimmer head10to rotate, and the motor21may specifically include a motor shaft211. In this example, the motor21also rotates about the rotation axis101. It is to be understood that in other examples, the motor shaft211may not rotate about the rotation axis101. For example, the motor shaft211may rotate about a straight line parallel to the rotation axis101, and the motor shaft211may also rotate about a straight line perpendicular to the rotation axis101. The motor housing212is used for accommodating the motor21. The motor housing212may be formed with an accommodation cavity in which the motor21is disposed. The transmission assembly22is configured to transmit power between the motor21and the grass trimmer head10.

The motor211is specifically an electric motor, which is further a brushless electric motor, and further, the electric motor is an outer rotor brushless electric motor. The electric motor includes a rotor assembly and a stator assembly, where the rotor assembly includes a rotor shaft, and the rotor shaft is the motor shaft211.

The grass trimmer head10is configured to drive the grass trimmer rope102to rotate at a high speed to cut vegetation, and the grass trimmer head10includes a head housing11and a spool12. The spool is used for the grass trimmer rope102to be wound around, and the head housing11is used for accommodating the spool12. The spool12is disposed in an accommodation space surrounded by the head housing11.

The front end device100afurther includes the user-operable operating device30disposed on the drive device20, and the operating device30may be operated to wind the rope.

Further, the operating device30includes a winding state and a non-winding state. When the operating device30is in the winding state, the operating device30is in a transmission connection with the motor21to drive the grass trimmer head10so that the spool12rotates relative to the head housing11about the rotation axis101as an axis, thereby winding the rope. When the operating device30is in the non-winding state, the operating device30is disengaged from the motor21.

Specifically, the grass trimmer has an automatic winding mode, a manual winding mode, and a grass trimming mode. It can also be considered that the grass trimmer head10has an automatic winding mode, a manual winding mode, and a grass trimming mode. When the grass trimmer head10is in the automatic winding mode, the motor21may drive the spool12to rotate relative to the head housing11about the rotation axis101along the first rotation direction, thereby automatically winding the grass trimmer rope102around the spool12. When the grass trimmer head10is in the manual winding mode, the operating device30is in the winding state, the user may rotate the spool12relative to the head housing11about the rotation axis101along the first rotation direction through the operating device30, and the grass trimmer rope102may be wound around the spool12. When the user activates the motor21by operating the operation switch, the motor21can drive the spool12to rotate about the rotation axis101along the second rotation direction so that the grass trimmer is in the grass trimming mode. In this example, when viewed from the motor21to the grass trimmer head10, the first rotation direction may be regarded as a counterclockwise direction, and correspondingly, the second rotation direction may be regarded as a clockwise direction, but it is not limited thereto. It is to be understood that in other examples, the motor shaft211may also be connected to the head housing11to drive the head housing11to rotate; in this manner, when the grass trimmer head10is in the automatic winding mode, the motor21drives the head housing11to rotate so that the spool12rotates relative to the head housing11along the first rotation direction, thereby automatically winding the grass trimmer rope102around the spool12. Similarly, the operating device30may be connected to the head housing11; when the grass trimmer head10is in the manual winding mode, the user operates the operating device30to drive the head housing11to rotate so that the spool12rotates relative to the head housing11along the first rotation direction, thereby winding the grass trimmer rope102around the spool12.

In this manner, the grass trimmer head10may not only transmit power from the motor21to the spool12, thereby automatically winding the grass trimmer rope102, but also transmit the power from the operating device30to the spool12, thereby winding the grass trimmer rope102around the spool12so that the user may either automatically wind the grass trimmer rope102by triggering the operation switch, or manually wind the grass trimmer rope102through the operating device30, and thus a manual and automatic integrated grass trimmer is truly provided. In this manner, on the one hand, when the user rotates the operating device30to wind the grass trimmer rope102, the user may feel fatigued. At this time, the user may operate the operation switch so as to automatically wind the grass trimmer rope102around the spool12, thereby facilitating the operation of the user and improving the operation efficiency. In addition, when the automatic winding mode of the grass trimmer fails, the user may also manually wind the grass trimmer rope102around the spool12through the operating device30, thereby improving the reliable performance of the grass trimmer; and the problem of the tangled rope and dirty hands caused by the hands in contact with the grass trimmer head when the rope is manually wound can be avoided, thereby improving the winding speed and the user experience and improving the operation efficiency.

The operating device30specifically includes a crank handle31and a rotary button32. The crank handle31is hinged on a top of the rotary button32, and the crank handle31is used for pressing the rotary button32downward when the operating device30is in the winding state so that the rotary button32is connected to the motor shaft211of the motor21, and the crank handle31is rotated by an external force, thereby winding the rope; when the operating device30is in the non-winding state, the rotary button32and the motor shaft211are in a separated state. Specifically, the crank handle31may rotate from a vertical position (a position parallel to the rotation axis101) to a horizontal position. When the crank handle31is at the vertical position, the crank handle31is pressed downward so as to drive the rotary button32downward to be connected to the motor shaft211. It is to be understood that when the crank handle31is at an inclined position, the crank handle31may also be pressed downward, but the operation efficiency is low.

Further, the operating device30further includes an elastic reset member33, two ends of which act on the rotary button32and the motor housing212, respectively. In the winding state, the elastic reset member33is in a compressed state; in the non-winding state, the rotary button32and the motor shaft211are in a separated state under the action of the elastic reset member33. The elastic reset member33is provided so that the operating device30can quickly switch between the winding state and the non-winding state, and the structure is simple, easy to implement, and low in cost.

The motor21further includes a shaft sleeve213. The shaft sleeve213is sleeved on a top of the motor shaft211and can drive the motor shaft211to rotate. In the winding state, the rotary button32is connected to the shaft sleeve213to achieve the transmission connection with the motor shaft211; in the non-winding state, the rotary button32and the shaft sleeve213are in a separated state. The shaft sleeve213is provided so that the motor shaft211can be avoided from being worn, and the service life of the motor shaft211can be prolonged.

The operating device30further includes an annular cover plate34, the annular cover plate34is connected to a top of the motor housing212and forms an accommodation cavity with the motor casing212, the rotary button32is located in the accommodation cavity, and the crank handle31is at least partially located outside the annular cover plate34so that the crank handle31is operable. When the operating device30is in the non-winding state, the rotary button32and the shaft sleeve213of the motor shaft211are in a separated state under the action of the elastic reset member33. When the operating device30is in the winding state, the user needs to turn the crank handle31to the vertical position, the rotary button32is pressed through the crank handle31until the rotary button32mates with the shaft sleeve213on the motor shaft211, and then the crank handle31is rotated, thereby winding the rope. After a winding operation is completed, the crank handle31is released and placed at the horizontal position.

Further, the annular cover plate34is provided with a positioning groove341, one end of the crank handle31is hinged to the rotary button32, and the other end of the crank handle31may be lifted to the vertical position or placed flat at the horizontal position to be clamped in the positioning groove341. The positioning groove341is provided so that it is convenient to store the crank handle31. Furthermore, a hand-locking groove342is disposed on a side of an outer circumference of the annular cover plate34away from a position where the crank handle31is hinged to the rotary button32, the hand-locking groove342communicates with the positioning groove341, and the hand-locking groove342is provided, which is convenient for the hands to lift the crank handle31.

Preferably, the rotary button32has a T-shaped cross section and includes a limiting portion321and a rotating portion322that are vertically connected. The crank handle31is hinged to a top surface of the limiting portion321. In the non-winding state, under the action of the elastic reset member33, an upper surface of the limiting portion321abuts against an inner top surface of the annular cover plate34, that is, the inner top surface of the annular cover plate34has a certain limiting effect on the rotary button32; in the winding state, under the pressing action of the crank handle31, a certain distance exists between the limiting portion321and the inner top surface of the annular cover plate34. The rotating portion322is connected to a lower surface of the limiting portion321, and the rotating portion322is configured to be connected to the shaft sleeve213. Specifically, the rotating portion322is clamped to the shaft sleeve213.

Further, a middle part of the rotating portion322is provided with a clamping hole, and the shaft sleeve213is clamped to the clamping hole. Preferably, the clamping hole is a special-shaped hole, and an outer peripheral shape of the shaft sleeve213is adapted to a shape of the special-shaped hole so that the shaft sleeve123may rotate with the rotating portion322. A special-shaped structure is provided so that a connector is not provided, the cost is saved, and the reliability is relatively high.

The elastic reset member33is sleeved on an outer circumference of the rotating portion322, a limiting groove is disposed on the motor housing212, an upper end of the elastic reset member33abuts between the limiting portion321and the rotating portion322, and a lower end of the elastic reset member33is located in the limiting groove. Preferably, the elastic reset member33is a pagoda-shaped spring. The pagoda-shaped spring has advantages of a small volume and a large load, is suitable for small spaces, and has a certain shock absorption effect so that a smooth winding process can be ensured.

The above illustrates and describes basic principles, main features, and advantages of the present disclosure. It is to be understood by those skilled in the art that the preceding examples do not limit the present disclosure in any form, and technical solutions obtained by means of equivalent substitution or equivalent transformation fall within the scope of the present disclosure.