37results about How to "Realize the shift function" patented technology

The invention discloses a shifting register and a driving method thereof as well as a grid electrode driving circuit and a display device, relating to the field of display. A needed electrical level can be stably output and bad phenomena caused by the fact that the output is not stable when a clock signal is converted and an output signal is interfered are eliminated, so that the display quality is guaranteed. According to the shifting register, an input module is used for sending an input signal to an output module, a resetting module and a maintaining module according to an input signal and a first clock signal; the resetting module is connected with the input module and a signal output end and is used for resetting a signal output end according to the first clock signal, first and second electrical level signals and the input signal; the maintaining module is connected with the input module and the output module and is used for sending a maintaining signal to the output module according to the input signal, the second clock signal and the second electrical level signal; and the output module is connected with the input module, the maintaining module and the signal output end and is used for sending the output signal to the signal output end according to the input signal, the maintaining signal and the second clock signal.

The embodiment of the invention provides a shift register unit, a display panel and a display device, and aims at solving the problem of high unnecessary power consumption in the stage of non-working caused by the fact that the shift register unit is controlled by a pair of complementary and inverted clock signals. When a selection signal is in high level, a latch circuit outputs the clock signals received by a first clock signal end of the latch circuit and a low-level signal after nor-operation; in the first low-level period of time of the selection signal, the signals output by the latch circuit, when the selection signal is in the high level, are subjected to not-operation to obtain new signals, and the new signals and a feedback signal are output after being subjected to nor-operation; in the period of time except for the first low-level period of time of the selection signal of the period of time when the selection signal is in low level, the low-level signal is output. When the output of latch signal is in the high level, a transmission circuit outputs signals relative to the clock signals received by the first clock signal end of the transmission circuit; when the output of latch signal is in the low level, the transmission circuit outputs a level signal.

Disclosed is a control system of an AMT power takeoff. The control system of the AMT power takeoff comprises an automatic gearbox. The automatic gearbox is provided with an AMT control unit. A middleshaft of the automatic gearbox is provided with a power takeoff body. The power takeoff body is provided with a position switch and a power takeoff clutch. The AMT control unit is in signal connectionwith an instrument, a power takeoff switch, a power takeoff solenoid valve, a clutch, an engine control unit, a shift handle and a position switch. One end of the clutch is connected with an engine mechanically. The engine is in signal connection with the engine control unit. The other end of the clutch is connected with the automatic gearbox mechanically. The power takeoff clutch is connected with one end of the power takeoff solenoid valve in a gas rode mode. The other end of the power takeoff solenoid valve is connected with a whole vehicle gas source in a gas road mode. The power takeoffbody is mechanically connected with a power takeoff device through a transmission shaft. According to the design of the control system of the AMT power takeoff, shift function can not only be achievedduring driving power takeoff, but also braking and driving power takeoff of a traditional mechanical gearbox can be achieved, operation is simple, and the reliability is high.

The invention relates to a multi-stage backward gear speed changer with a slide shaft roller keylock, which mainly comprises a main speed reducing mechanism, a transmission gear shaft, a transmission gear, a speed changing gear, a gear isolating ring, a power output shaft, a roller keylock device, a speed-regulating ring, a gear state determining device and a gear speed-regulating device. The multi-stage backward gear speed changer is provided with a gear state and a gear position. After power is inputted to a power input shaft, the gear state of the power input shaft is determined, and then primary speed reduction is carried out. All transmission gears on the transmission gear shaft are meshed with corresponding speed-changing gears. When the roller keylock is in a non-locked state, the speed-changing gears freely rotate relative to a power output shaft, and the roller keylock is in a neutral state. During speed regulation, a keylock slide shaft is pulled by a gear pull fork, the speed-changing gear locked in one gear is selected by changing the position of the keylock so that the speed change is realized. During gear reversing, the keylock slide shaft is pulled by the gear pull fork to change the state of the gear, the backward gear is locked, a reverse torque is outputted, and the function of multi-stage gear reversing is realized. The multi-stage backward gear speed changer can be widely applied to the field of carrying tools.

The invention discloses an emergency unlocking parking lock device. The emergency unlocking parking lock device comprises a shell, a transmission part, a control module, a reversing valve, a hydrauliccontrol valve, an emergency valve, a hydraulic control closed type one-way valve with a first elastic part, an emergency oil conveying mechanism, an energy accumulator and a detection part. The shellcomprises a sealed cavity. The transmission part is movably arranged in the shell in a penetrating mode. The control module comprises a self-locking mechanism, and the self-locking mechanism can automatically lock the transmission part. The self-locking mechanism can release the transmission part under the control of the control module or the pressure of hydraulic oil in an emergency cavity. After the self-locking mechanism releases the transmission part, the hydraulic control closed type one-way valve with the first elastic part can unblock an oil way between the emergency valve and the hydraulic valve in a one-way mode. The emergency oil conveying mechanism can manually convey the hydraulic oil in an oil tank into a first connector and a second pilot oil way. By means of the emergency unlocking parking lock device, gear shifting of a vehicle in an emergency state can be well achieved.

The invention provides a gear selecting and shifting inhaul cable mechanism. The gear selecting and shifting inhaul cable mechanism comprises a supporting plate, a gear selecting inhaul cable slot support, a gear shifting inhaul cable slot support, a gear selecting inhaul cable fixing support, a gear shifting inhaul cable fixing support, a gear selecting connecting rod, a gear shifting connecting rod, a rotary support used for being connected with a gear selecting and shifting converter and a fixed plate used for being connected with a gear box body. The gear selecting and shifting inhaul cable mechanism is simple in structure, a gear selecting inhaul cable and a gear shifting inhaul cable are used for driving the gear selecting connecting rod and the gear shifting connecting rod correspondingly, then the gear selecting and shifting converter is driven to move, and therefore the functions of gear selecting and shifting are achieved. The gear selecting and shifting inhaul cable mechanism is compact in layout and low in cost; and by means of the mechanism, a via hole in the cab bottom plate of a basic vehicle model can be used by the gear selecting inhaul cable and the gear shifting inhaul cable, hole reopening of a cab bottom plate can be avoided, and additional mounting of cab gauges and clamps and rearrangement of a cab production line are avoided.

The invention discloses a forward and reverse full-overrun gear shifting mechanism. The mechanism comprises a driving shaft and a driven shaft, wherein a first-gear driving one-way clutch and a second-gear driving one-way clutch are fixedly sleeved on the driving shaft; a first-gear driven one-way clutch is fixedly sleeved on the driven shaft; a second-gear driven one-way / two-way clutch is arranged on the driven shaft; a first-gear driving gear in the first-gear driving one-way clutch is engaged with a first-gear driven gear in the first-gear driven one-way clutch; when the driving shaft rotates clockwise, the first-gear driving one-way clutch drives the first-gear driven one-way clutch to rotate anticlockwise and the first-gear driven one-way clutch drives the driven shaft to rotate anticlockwise; and when the driving shaft rotates anticlockwise, the second-gear driving one-way clutch drives the second-gear driven one-way / two-way clutch to rotate anticlockwise and the second-gear driven ne-way / two-way clutch drives the driven shaft to rotate anticlockwise. The mechanism has a simple and novel structure. Reliable gear shifting function and reverse gear function can be realized reliably through the one-way clutch and the one-way / two-way clutch.

The invention discloses a positive-operation inversion-transcending gear-changing mechanism. The gear-changing mechanism is characterized in that a driving shaft is fixedly sleeved with a first gear driving gear and a second gear driving gear, a driven shaft is fixedly sleeved with a first gear driven single two-way device, and the first gear driven single two-way device is indirectly connected with the first gear driving gear; when the driving shaft rotates in an anticlockwise manner, the first gear driving gear drives the first gear driven single two-way device to rotate in the anticlockwise manner, and the first gear driven single two-way device drives the driven shaft to rotate in the anticlockwise manner; the driven shaft is sleeved with a second gear driven isolator, and a second gear driving gear is meshed with a second gear driven gear in the second gear driven isolator; and when the driving shaft rotates in a clockwise manner, the second gear driven gear drives the second gear driven isolator to rotate in the anticlockwise manner, and the second gear driven isolator drives the driven shaft to rotate in the anticlockwise manner. The gear-changing mechanism provided by the invention has novel simple structure, and the gear-shifting function can be reliably realized through an isolator as well as a single two-way device and a ratchet mechanism.

The invention relates to a manual gear-shifting shifting fork structure of a low-power reducer. The manual gear-shifting shifting fork structure comprises a handle, a driving lever and a transmission shaft. The handle drives the driving lever to rotate. The driving lever is in key connection with the transmission shaft. A driving lever connecting block is disposed on the upper portion of the driving lever. A threaded hole for being connected with the handle is formed in the top of the driving lever connecting block. A through stepped hole is transversely formed in the driving lever connecting block. The left-end diameter of the stepped hole is larger than the right-end diameter of the same. A pin for being inserted into the positioning hole of a reducer box to aid positioning is mounted in the stepped hole. The left-end diameter of the pin is larger than the right-end diameter of the same. Due to the fact that the power of the reducer is low, and moment required by shifting fork gear shifting is low. The manual gear-shifting shifting fork structure is simple, easy to operate, low in cost, small in size and suitable for low-power double-speed-ratio reducers.

The invention provides a coaxial line planetary transmission gear ring output multi-gear speed change mechanism. The gearshift mechanism can adopt a planetary mechanism to realize gearshift in one direction, that is the gearshift mechanism is only provided with a forward gear, in addition, the gearshift mechanism can realize gearshift in two directions as needed, that is the gearshift mechanism is provided with both a forward gear and a reverse gear; the coaxial line planetary transmission gear ring output multi-gear speed change mechanism is provided with an input end and an output end; an input shaft inputs power; the final gear can be gear ring output and planet carrier output, and other gears are gear ring output; the rotating speed of the output end is low, so that compared with an input end gearshift mechanism, the output end gearshift mechanism is easier and more reliable in gearshift and higher in efficiency; and compared with a parallel-axis gearshift mechanism, the gearshift mechanism has the advantages of being small in occupied area, large in transmission ratio range, high in bearing capacity and capable of realizing speed change with a high speed ratio.

The present invention provides a planetary transmission shifting mechanism capable of shifting gears, which includes a shifting device and a planetary transmission mechanism. The planetary transmission mechanism is provided with an input shaft and an output end. The planetary transmission shifting mechanism includes two or more The gears, the output ends of each gear are connected as a whole, and the input shaft input power can be either the output of the ring gear or the output of the planetary carrier. This planetary transmission shift mechanism is widely used in construction machinery, petroleum machinery, and chemical machinery. , construction machinery, mining machinery, ship machinery, etc., the planetary gear shifting mechanism uses a planetary mechanism to realize multi-gear gear shifting. Using a planetary transmission drive mechanism, etc., the shift mechanism has the advantages of convenient and reliable gear shifting, a wide range of transmission ratios, high load-bearing capacity, and the ability to achieve large speed ratio shifts.

The invention discloses a unidirectional overrunning clutch gear shift mechanism, which comprise a driving shaft and driven shaft, wherein a first-shift driving gear and a second-shift driving gear are sleeved on the driving shaft, a first-shift driven one-way clutch is sleeved on the driven shaft, the first-shift driven gear of the first-shift driven one-way clutch is meshed with the first-shift driving gear, the first-shift driving gear drives the first-shift driven one-way clutch to rotate, and the first-shift driven one-way clutch drives the driven shaft to rotate; and a second-shift driven one-way / two-way clutch is sleeved on the driven shaft, the second-shift driving gear is meshed with a second-shift driven gear in the second-shift driven one-way / two-way clutch, the second-shift driving gear drives the second-shift driven one-way / two-way clutch to rotate, and the second-shift driven one-way / two-way clutch drives the driven shaft to rotate. The mechanism is simple and novel in structure and can realize gear shift reliably through the one-way clutch and the one-way / two-way clutch. The mechanism has the advantages of simple structure, small volume, easy maintenance and low cost.

The invention discloses a pure electric vehicle. The pure electric vehicle comprises an automatic transmission control module, an electric executing mechanism, a battery management module and a transmission device and is characterized in that the automatic transmission control module consists of a sensing signal collection device, a micro-controller MCU and a driving device; an output end of the sensing signal collection device is electrically connected with an input end of the micro-controller MCU; the sensing signal collection device consists of a frequency signal collection device, an analog quantity signal collection device and a switching value signal collection device; the frequency signal collection device consists of a motor rotation speed sensor, a transmission input shaft speed sensor and a transmission output shaft speed sensor; and the analog quantity signal collection device consists of a pedal position sensor, a pedal pressure sensor, a radar sensor and a gear position sensor. According to the pure electric vehicle, the gear shifting function of the electric vehicle is realized; and meanwhile, the safety and reliability of the operation of the whole system are enhanced.

The invention provides a gear shifting actuator with a manual unlocking function, and belongs to the technical field of vehicle gear shifting actuators. The gear shifting actuator comprises a housinghaving a sealed installing cavity and provided with an unlocking port, a power unit arranged in the installing cavity and a transmission unit arranged in the installing cavity, wherein the transmission unit is in linkage connection with the power unit, a manual driving end is arranged on the transmission unit, the manual driving end is aligned to the unlocking port, and when the power unit loses efficacy, an unlocking tool can be connected with the manual driving end through the unlocking port so as to drive the transmission unit to move. The gear shifting actuator has the beneficial effects that when the executor is powered off or cannot work, the executor can be driven in a manual mode, so that the gear shifting function is achieved, and the problem that a vehicle cannot move due to thefact that the executor breaks down is solved.

The invention discloses an overrunning gear-shifting device, which comprises a driving shaft and a driven shaft. A first-gear driving sprocket and a second-gear driving sprocket are fixedly sleeved on the driving shaft, a first-gear driven one-way clutch is fixedly sleeved on the driven shaft, a first-gear driven sprocket in the first-gear driven one-way clutch is connected with the first-gear driving sprocket, the first-gear driving sprocket drives the first-gear driven one-way clutch to rotate, and the first-gear driven one-way clutch drives the driven shaft to rotate. Besides, a second-gear driven one-way / two-way clutch is sleeved on the driven shaft, the second-gear driving sprocket meshes with the second-gear driven sprocket in the second-gear driven one-way / two-way clutch, the second-gear driving sprocket drives the second-gear driven one-way / two-way clutch to rotate, and the second-gear driven one-way / two-way clutch drives the driven shaft to rotate. The overrunning gear-shifting device is simple and novel, capable of realizing gear shifting by the aid of the one-way clutch, the one-way / two-way clutch and a ratchet mechanism, and has the advantages of simple structure, small size, easiness in maintenance and low cost.

The invention discloses a fully-unloaded gear shifting device which comprises a driving shaft and a driven shaft, a one-gear driving unidirectional clutch and a two-gear driving unidirectional clutch are fixedly sheathed on the driving shaft, and a one-gear driven unidirectional clutch is fixedly sheathed and a two-gear driven unidirectional and bidirectional clutch is installed on the driven shaft, wherein a unidirectional driving gear in the one-gear driving unidirectional clutch is meshed with a one-gear driven gear in the one-gear driven unidirectional clutch. When the driving shaft rotates counterclockwise, the one-gear driving unidirectional clutch drives the one-gear driven unidirectional clutch to rotate clockwise, and the one-gear driven unidirectional clutch drives the driven shaft to rotate clockwise. When the driven shaft rotates clockwise, the two-gear driving unidirectional clutch drives a steering gear to rotate counterclockwise, the steering gear drives the two-gear driven unidirectional and bidirectional clutch to rotate clockwise, and the two-gear driven unidirectional and bidirectional clutch drives the driven shaft to rotate clockwise. The fully-unloaded gear shifting device has novel structure, the gear shifting function can be reliably realized via the unidirectional clutches and the unidirectional and bidirectional clutch, and the reserve gear function can also be realized.

The invention relates to a brake gear shifting device based on motor driving and a vehicle. The brake gear shifting device comprises an assisting motor, a transmission mechanism and a gear shifting mechanism. The transmission mechanism comprises a screw rod, a nut, a cylindrical gear sleeve and a guide key, wherein an external thread is arranged on the screw rod, an internal thread matched with the external thread on the screw rod is arranged on the nut, the nut is in threaded connection with the screw rod, the cylindrical gear sleeve is arranged on the screw rod in a sleeving mode, clamping teeth are arranged at the bottom of the cylindrical gear sleeve, the nut and the cylindrical gear sleeve are connected through the guide key, the guide key is used for driving the cylindrical gear sleeve to do reciprocating linear motion on the screw rod along with the nut, and the screw rod is in transmission connection with the assisting motor. The gear shifting mechanism comprises a fan-shaped gear, a cam shaft and a cam, wherein the fan-shaped gear is engaged with the clamping teeth at the bottom of the cylindrical gear sleeve, one end of the fan-shaped gear is connected with the cam shaftthrough a spline, and the cam shaft is arranged on the cam. The self-locking performance is good, and the service life is long.

The invention discloses an emergency unlocking parking lock device. The emergency unlocking parking lock device includes a housing, a transmission part, a control module, a reversing valve, a hydraulic control valve, an emergency valve, and a hydraulic control valve with a first elastic part. Closed check valve, emergency oil delivery mechanism, accumulator and detection parts. The housing has a sealed cavity. The transmission member can be movably passed through the casing. The control module includes a self-locking mechanism, which can automatically lock the transmission part. The self-locking mechanism can release the transmission part under the control of the control module or under the pressure of the hydraulic oil in the emergency chamber. After the self-locking mechanism releases the transmission part, the hydraulically controlled closing check valve with the first elastic part can conduct the oil circuit between the emergency valve and the hydraulic valve in one direction. The emergency oil delivery mechanism can manually deliver the hydraulic oil in the oil tank to the first interface and the second pilot oil circuit. The emergency unlocking and parking lock device of the present invention can better realize gear shifting of the vehicle in an emergency state.

The invention belongs to the technical field of fitness equipment, and particularly relates to portable multifunctional fitness equipment. The equipment comprises an equipment main shell, and the equipment main shell is provided with a plurality of driving wheel rotating parts which are symmetrical along the center line of the equipment main shell. Through the arrangement of the driving wheel rotating parts, a power output wheel, a driving wheel self-resetting piece and a variable-speed power storage assembly, a user pulls a pull rope, in the pulling process of the pull rope, a recovery rope drives the power output wheel to rotate, forward and reverse rotation can be controlled through a clutch connecting piece to transmit power, power is transmitted into the variable-speed power storage assembly through the power output wheel, the variable-speed power storage assembly can conduct variable-speed adjustment, the power is converted into electric energy to be stored in the variable-speed power storage assembly after adjustment, power generation and energy storage are conducted in the exercise process, the body is exercised, energy is saved, the environment friendliness is good, meanwhile, carrying is convenient, exercise can be carried out in various scenes, and the practicability is high.

Embodiments of the present invention provide a shift register unit, a display panel, and a display device to solve the problem of unnecessary large power consumption in non-working stages caused by using a pair of complementary and inverted clock signals to control the shift register unit question. Among them, the latch circuit, when the selection signal is at a high level, outputs the clock signal received by its first clock signal terminal and the low-level signal after NOR operation; and in the first low-level period of the selection signal , performing a non-operation on the signal output by the latch circuit when the selection signal is at a high level, and then outputting the NOR operation with the feedback signal; and dividing the selection signal during the time period when the selection signal is at a low level During the time period other than the first low-level period, the transmission circuit outputs a low-level signal; when the output of the latch circuit is high-level, the transmission circuit outputs a signal related to the clock signal received by its first clock signal terminal; and When the output of the latch circuit is low level, a level signal is output.

The invention provides a gear shifting assembly, a gear shifting box and a vehicle. The gear shifting assembly comprises a gear shifting shaft, a first driving part and a second driving part, the first driving part is arranged on one side of the gear shifting shaft, and the first driving part is provided with a first working face; the second driving part is arranged on one side of the first driving part and provided with a second working face, the first working face and the second working face are constructed to be spherical curved surfaces arranged in a protruding mode, and the distance between the sphere center of the first working face and the axis of the gear shifting shaft is smaller than that between the sphere center of the second working face and the axis of the gear shifting shaft. The two center distance combined working faces are beneficial to gear shifting acceleration in the later stage of gear shifting, gear shifting force is reduced, gear shifting secondary impact is relieved, and gear shifting quality is improved.

The invention discloses a unidirectional overrunning clutch gear shift mechanism, which comprise a driving shaft and driven shaft, wherein a first-shift driving gear and a second-shift driving gear are sleeved on the driving shaft, a first-shift driven one-way clutch is sleeved on the driven shaft, the first-shift driven gear of the first-shift driven one-way clutch is meshed with the first-shiftdriving gear, the first-shift driving gear drives the first-shift driven one-way clutch to rotate, and the first-shift driven one-way clutch drives the driven shaft to rotate; and a second-shift driven one-way / two-way clutch is sleeved on the driven shaft, the second-shift driving gear is meshed with a second-shift driven gear in the second-shift driven one-way / two-way clutch, the second-shift driving gear drives the second-shift driven one-way / two-way clutch to rotate, and the second-shift driven one-way / two-way clutch drives the driven shaft to rotate. The mechanism is simple and novel in structure and can realize gear shift reliably through the one-way clutch and the one-way / two-way clutch. The mechanism has the advantages of simple structure, small volume, easy maintenance and low cost.

The invention discloses an overhead gear shift system. A first-gear driving chain wheel and a second-gear driving gear are fixedly sleeved on a driving shaft; a first-gear driven bidirectional-unidirectional device is fixedly sleeved on a driven shaft and is connected with the first-gear driving chain wheel by using a chain; when the driving shaft anticlockwise rotates, the first-gear driving chain wheel drives the first-gear driven bidirectional-unidirectional device to anticlockwise rotate and the first-gear driven bidirectional-unidirectional device drives the driven shaft to anticlockwise rotate; a second-gear driven bidirectional-unidirectional device is sleeved on the driven shaft; the second-gear driving gear is meshed with a second-gear driven gear in the second-gear driven bidirectional-unidirectional device; and when the driving shaft clockwise rotates, the second-gear driving gear drives the second-gear driven bidirectional-unidirectional device to anticlockwise rotate and the second-gear driven bidirectional-unidirectional device drives the driven shaft to anticlockwise rotate. The overhead gear shift system disclosed by the invention is novel in structure; and the gear shift function can be reliably achieved through a unidirectional device, the bidirectional-unidirectional devices and a ratchet mechanism.

The invention provides a special vehicle, which comprises a vehicle frame, a driving axle, walking wheels, a rear axle steering device and a power system, wherein the driving axle comprises a drivingaxle housing arranged below the vehicle frame, a mounting bracket and a hydraulic motor mounted at the mounting bracket, the walking wheels are installed at the end of the drive axle housing, connected with the hydraulic motor and further driven to rotate, the rear axle steering is arranged at the rear portion of the vehicle frame, the power system comprises an engine, a hydraulic main pump, an assembling bracket and a transmission pump, the engine is provided with two output shafts arranged in parallel, the output shafts rotate around the axes of the output shafts, the hydraulic main pump islocated on one side of the engine and connected with one output shaft of the engine and the hydraulic motor so as to drive the hydraulic motor, The assembling bracket and the hydraulic main pump are located on the same side of the engine, a height difference exists between the assembling bracket and the hydraulic main pump, the transmission pump is mounted at the assembling bracket, and the transmission pump is connected with the other output shaft of the engine so as to drive the rear axle to steer.

The invention relates to a self actuating speed synchronous tracking insertion gear-shifting gear. Before a driving wheel is inserted to conduct gear shifting, a controllable clutch enables a driven synchronous gear to be separated, a synchronous tracking motor drives the driven synchronous gear to rotate, driven synchronous gear synchronization is achieved by collecting speed signals of the driving wheel and driving the driven synchronous gear with the synchronous tracking motor, relative rest of opposite teeth can be achieved, at the time, the driving wheel is rapidly pushed to be inserted into the teeth of the driven synchronous gear by an electromagnetic pull force valve through a shifting fork, the controllable clutch then works to output power, and the gear shifting function is achieved.

The invention discloses a gear transmission for a power output shaft for an electromagnetic keylock. The gear transmission consists of a main reducing gear, transmission gears, a speed regulation gear, an electromagnetic keylock output shaft, an electromagnetic speed regulation ring, a gear reversing device, and a gear shift device. All transmission gears on a transmission gear shaft are meshed with the corresponding change gears; and when the keylock is in a non-locked state, the change gear freely rotates relative to the power output shaft so as to show a neutral position state. When the speed is regulated, the gear is changed by pushing a gear shift handle, positive electricity is conducted to an electric conduction metal ring through a speed regulation ring carbon brush, an electromagnetic keylock coil electromagnetic jack coil is connected, magnetic attraction is performed, and the keylock is opened to select the change gear which locks a certain gear so as to realize the gear adjustment. During gear reversing, a gear reversing keylock is ejected from a keylock window, the power output shaft and a gear reversing gear are locked, and the power output shaft outputs reactive torque so as to realize the gear shift function. The invention has the advantages that: by the gear transmission, the gear is easy to shift, the gear has few components, the gear transmission is used reliably, and has light weight, and the like. The gear transmission can be widely applied to the field of carrying tools.