Self-adaptive suspension load-reducing bearing system

Abstract

The invention provides a self-adaptive suspension load-reducing bearing system. The self-adaptive suspension load-reducing bearing system comprises a back frame unit, a transmission unit and a self-adaptive driving module, the self-adaptive driving module comprises a driving unit, a variable stiffness unit and a control unit which are positioned in the rack; the rack body is fixedly connected with a mover rack of the back frame unit, an external connection end fixedly connected with a gear of the transmission unit is arranged on the rack body, a load transmitted by the transmission unit is connected through the external connection end, and power provided by the driving unit is transmitted to the mover rack; the driving unit comprises a central shaft and a driving motor which are coaxial; a rigidity adjusting assembly in the variable rigidity unit changes the number of working turns of the coil spring according to an instruction of the control unit, and the load torque transmitted by the center shaft acts on the coil spring; the control unit controls the rigidity adjusting assembly and the driving motor according to the current of the driving motor and the rotating angle of the center shaft, power is provided for the mover rack to enable the mover rack to maintain the target position, meanwhile, self-adaptive adjustment on different loads is achieved, the adjusting range is wide, the weight is low, and energy consumption is low.

Description

Technical Field

[0001] The present disclosure relates to the technical field of carrying devices, and in particular to an adaptive suspension load-reducing carrying system. Background Art

[0002] When people are hiking, rescuing or in military operations, they often need to walk long distances with loads (>10km, 30-70kg). This is characterized by long time, strong rhythm, and monotonous gait, which is prone to cumulative fatigue problems and is also a great test for the spirit and psychology. When walking with a load, the center of gravity of the human body fluctuates up and down in the vertical direction, and the backpack load will generate additional inertial force to increase the burden on the trunk and lower limbs. This inertial force can be up to 2-3 times the static load, which can easily cause physical decline, muscle fatigue and even injury. By adding a suspension carrying system with damping and stiffness units to the carrying system, the muscle activity and energy consumption involved in the carrying activity can be effectively reduced to avoid damage to the human body.

[0003] The load-reducing effect of the suspended backpack system is affected by the damping and stiffness of the system, while the damping and stiffness adjustment range of the traditional purely mechanical suspended backpack system is small, or even fixed. This limits the applicability of the traditional suspended backpack system to fixed load and step frequency conditions, while under other conditions the load-reducing effect deteriorates or even increases the load.

[0004] In order to make the suspended backpack system suitable for different load-bearing scenarios, a load-reducing backpack system with adjustable damping and stiffness came into being, which can automatically adjust the system stiffness and damping according to the size of the different loads. However, the adjustment modules used in the existing adaptive load-bearing backpack systems have complex structures and occupy a large space, which will increase the weight of the backpack system itself, and the additional weight will increase the energy consumption of the human body's carrying activities; the adjustment modules used are mostly active modules without elastic elements. Such active modules directly drive the load to generate a large current and consume electrical energy. In addition, the existing adaptive load-bearing backpack systems cannot be used in scenarios with changing cadence, and cannot identify the user's cadence. Although the existing backpack systems can manually change stiffness and damping to achieve frequency changes, the actual operation is more cumbersome.

[0005] On the other hand, when using a backpack for outdoor activities, electronic products are often needed to be carried and charged. The power-generating suspension backpack system can convert the kinetic energy of the load movement into electrical energy for storage. The current power-generating backpack system also increases the weight of the backpack due to its complex mechanical structure. Summary of the invention

[0006] The present disclosure aims to solve at least one of the technical problems existing in the prior art.

[0007] To this end, the present invention provides an adaptive suspension load-reducing carrying system, which has a good load-reducing effect and is suitable for various loads or step frequencies. The stiffness of the carrying system can be adaptively adjusted according to the step frequency during load-bearing activities. It has a sophisticated structure, light weight and low energy consumption.

[0008] In order to achieve the above objectives, the present disclosure adopts the following technical solutions:

[0009] The present disclosure provides an adaptive suspension carrying system, comprising a back frame unit, a bag body, a transmission unit and an adaptive driving module;

[0010] The back frame unit comprises a mover frame, a stator frame and a guide module, wherein the guide module is connected between the mover frame and the stator frame and is used to limit the mover frame to only reciprocate along the normal direction of the cross section of the carrying system relative to the stator frame, and a shoulder belt is provided on the side of the stator frame facing away from the mover frame;

[0011] The enclosure is fixedly connected to a side of the mover frame facing away from the stator frame;

[0012] The transmission unit is arranged between the mover frame and the stator frame, and includes a rack and a gear meshed by a toothed portion, wherein the rack is arranged along the normal direction of the cross section of the carrying system and is fixedly connected to the stator frame;

[0013] The adaptive driving module comprises a frame, and a driving unit, a variable stiffness unit and a control unit arranged in the frame;

[0014] The frame includes a frame body fixedly connected to a side of the mover frame facing away from the stator frame and an external connection end provided on the frame body, wherein the external connection end passes through a first hole on the mover frame and is fixedly connected to the gear, a load transmitted by the transmission unit is connected through the external connection end, and power provided by the drive unit is transmitted to the mover frame and the package body;

[0015] The driving unit comprises a coaxially arranged central shaft and a driving motor, and the power output by the driving motor is transmitted to the external end through the central shaft;

[0016] The variable stiffness unit comprises an elastic element and a stiffness adjustment component, wherein the stiffness adjustment component is connected to the elastic element and the central axis of the drive unit, the load torque is transmitted to the stiffness adjustment component through the central axis, and then the torque is applied to one end of the elastic element, the stiffness adjustment component changes the working number of turns and the output torque of the elastic element by unidirectional or bidirectional locking of one end of the elastic element, thereby balancing the corresponding load torque, and the stiffness adjustment component adjusts the initial angle of the elastic element by pre-tightening or unloading the other end of the elastic element, and the initial angle of the elastic element corresponds to the initial position of the mover frame relative to the stator frame;

[0017] The control unit is used to control the stiffness adjustment component and the drive motor according to the current signal of the drive motor and the rotation angle signal of the central shaft, so as to achieve a balance among the load torque, the elastic element torque and the output torque of the drive motor, and realize adaptive adjustment of different load sizes while providing power to the mover frame and the package to maintain the target position.

[0018] In some embodiments, the guide module includes two L-shaped guide rails respectively fixedly arranged on the left and right sides of the mover frame and a plurality of guide wheel groups installed on the side of the stator frame facing the mover frame, the horizontal section and the vertical section of each L-shaped guide rail serve as a horizontal guide rail and a vertical guide rail respectively; a plurality of guide wheel groups are evenly distributed on the left and right sides of the stator frame, each guide wheel group comprises two horizontal guide wheels and one vertical guide wheel respectively, the two horizontal guide wheels are arranged at the front and rear sides of the horizontal guide rail and are rotatably sleeved on a corresponding horizontal guide wheel shaft fixedly connected to the stator frame, the vertical guide wheel is located on the inner side of the vertical guide rail and is rotatably sleeved on the vertical guide wheel shaft fixedly connected to the stator frame; during the movement of the mover frame relative to the stator frame, the horizontal guide wheel and the horizontal guide rail generate rolling friction, and the vertical guide wheel and the vertical guide rail generate rolling friction, respectively constraining the movement of the mover frame in the normal direction of the coronal plane and the normal direction of the sagittal plane of the carrying system;

[0019] A first limit block and a second limit block are respectively provided at the upper portion of the mover frame and at corresponding positions of the stator frame. When the mover frame reaches the maximum downward displacement relative to the stator frame, the lower portion of the first limit block conflicts with the upper portion of the second limit block.

[0020] In some embodiments, a locking mechanism is further provided between the mover frame and the stator frame and close to the lower part of the stator frame, and the locking mechanism includes a locking plug and a locking hook; the locking plug is rotatably sleeved on a locking plug shaft fixedly connected to the stator frame, and the locking hook is rotatably sleeved on a locking hook shaft fixedly connected to the stator frame, and a first slot matching one end of the locking plug is provided on the locking hook, and a second slot matching one end of the locking hook away from the locking hook shaft is provided at the lower part of the mover frame facing the stator frame; when one end of the locking hook is inserted into the second slot and one end of the locking plug is inserted into the first slot, the mover frame and the stator frame are in a locked state; when one end of the locking plug is disengaged from the first slot and one end of the locking hook is disengaged from the second slot, the mover frame and the stator frame are in an unlocked state.

[0021] In some embodiments, the transmission unit further includes an auxiliary gear, which is rotatably mounted on an auxiliary gear shaft fixed to a side of the mover frame facing the stator frame, and the auxiliary gear and the gear are arranged on the left and right sides of the rack.

[0022] In some embodiments, the elastic element is a nonlinear elastic element, which is composed of a first sub-coil spring and a second sub-coil spring connected in series through the stiffness adjustment component, the first sub-coil spring is arranged closer to the central axis than the second sub-coil spring, and each sub-coil spring is a linear coil spring, or a nonlinear coil spring, or one of them is a linear coil spring and the other is a nonlinear coil spring; the nonlinear coil spring is a planar spiral spring formed by a plurality of coil spring segments connected end to end in sequence and integrally formed, and the stiffness of two adjacent coil spring segments is different;

[0023] The stiffness adjustment assembly includes a first stiffness adjustment mechanism and a second stiffness adjustment mechanism, the first stiffness adjustment mechanism includes a first sub-coil spring locking piece and a first sub-coil spring driving frame fixedly connected to the central axis, the second stiffness adjustment mechanism includes a second sub-coil spring locking piece and a second sub-coil spring driving frame, each sub-coil spring driving frame can be rotated relative to the frame body and is respectively fixedly connected to the outer ends of the first sub-coil spring and the second sub-coil spring; each sub-coil spring locking piece respectively includes a ratchet pawl mechanism and a matching stop switch and a reset spring, each ratchet pawl mechanism shares a ratchet shaft, the ratchet shaft is coaxially arranged with the central axis and is rotatably connected to the frame body, a coil spring inner end adjustment piece is provided at the end of the ratchet shaft away from the central axis, the ratchet shaft is rotated by the coil spring inner end adjustment piece to adjust the inner end angle of each sub-coil spring to achieve pre-tightening or unloading of the inner end of each sub-coil spring, the first ratchet pawl mechanism is connected to The second ratchet pawl mechanism is connected between the inner end of the second sub-coil spring and the lower end surface of the second sub-coil spring driving frame; each reset spring always remains in a compressed state, used to provide a force for the corresponding stop pawl to approach the direction of each ratchet; during the stiffness adjustment process of the elastic element, the first sub-coil spring locking piece remains in a locked state with the second sub-coil spring driving frame according to the instruction of the control unit, so as to realize the series connection of the first sub-coil spring and the second sub-coil spring, and the stop switch in the second sub-coil spring locking piece increases or decreases the working turns of the first sub-coil spring and the second sub-coil spring at the same time according to the instruction of the control unit until the load torque, the torque of the nonlinear elastic element and the output torque of the drive motor are balanced, and the control unit controls all the stop switches to lock the inner ends of the first sub-coil spring and the second sub-coil spring at the same time.

[0024] Furthermore, assuming that the first sub-coil spring is provided with P coil spring segments, the second sub-coil spring is provided with Q coil spring segments, P and Q are both positive integers greater than or equal to 1, when the number of segments of the sub-coil spring is 1, the sub-coil spring is a linear coil spring, and when the number of segments of the sub-coil spring is greater than 1, the sub-coil spring is a nonlinear coil spring; the nonlinear elastic element is designed according to the following steps: the given working curve of the adaptive drive module is divided into S segments, the working curve of the adaptive drive module is the angle of the central axis and the angle of the external The functional relationship between the torque output at the end is obtained, the total number of segments of the nonlinear elastic element is taken as S, that is, S=P+Q, and the first coil spring segment is located at the outer ring of the first sub-coil spring; the i-th section working curve and its slope are respectively used as the working curve and stiffness of the i-th coil spring segment, i=1,2,...,S, and the i-th coil spring segment is designed according to the industry standard JB / T7366-1994 to obtain the parameters of the i-th coil spring segment, including elastic modulus E, section thickness h, section width b and unfolded length l.

[0025] Further, the first ratchet pawl mechanism includes a first ratchet rotatably sleeved on the ratchet shaft, and a first positive stop pawl and a first negative stop pawl matched with the first ratchet through a tooth portion, the inner end of the first sub-coil spring is fixedly connected to the first ratchet, and the ends of the first positive stop pawl and the first negative stop pawl away from their respective tooth portions are rotatably connected to the lower end surface of the second sub-coil spring driving frame, a first positive return spring and a first positive stop switch are provided between an end of the first positive stop pawl close to its tooth portion and the lower end surface of the second sub-coil spring driving frame, and a first negative return spring and a first negative stop switch are provided between an end of the first negative stop pawl close to its tooth portion and the lower end surface of the second sub-coil spring driving frame;

[0026] The second ratchet pawl mechanism comprises a second ratchet wheel fixedly sleeved on the ratchet shaft, and a second positive stop pawl and a second negative stop pawl matched with the second ratchet wheel through a tooth portion, the inner end of the second sub-coil spring is fixedly connected to the second ratchet wheel, and one end of the second positive stop pawl and the second negative stop pawl away from their respective tooth portions are rotatably connected to the lower end surface of the top cover of the frame body, a second positive return spring and a second positive stop switch are provided between one end of the second positive stop pawl close to its tooth portion and the lower end surface of the top cover of the frame body, and a second negative return spring and a second negative stop switch are provided between one end of the second negative stop pawl close to its tooth portion and the lower end surface of the top cover of the frame body;

[0027] During the adjustment process of the elastic element, the first ratchet and the second coil spring drive frame remain in a locked state, and at most only one of the two stop pawls matching the second ratchet is in contact with the tooth portion of the second ratchet; when the load torque, the torque of the elastic element and the output torque of the drive motor are balanced, the two stop pawls matching the same ratchet are both in contact with the tooth portion of the ratchet.

[0028] In some embodiments, the elastic element is a single nonlinear coil spring formed by a plurality of coil spring segments connected end to end in sequence and integrally formed, and the stiffness of two adjacent coil spring segments is different;

[0029] The stiffness adjustment assembly includes a stiffness adjustment mechanism, which includes a coil spring inner end adjustment member, a coil spring locking member and a coil spring driving frame fixedly connected to the central axis; the coil spring inner end adjustment member is arranged at the center of the top cover of the frame body, and is used to adjust the inner end rotation angle of the nonlinear coil spring to achieve pre-tightening or unloading of the inner end of the nonlinear coil spring; the coil spring driving frame can rotate relative to the frame body and is fixedly connected to the outer end of the nonlinear coil spring; the coil spring locking member includes a ratchet pawl mechanism and a matching stop switch and a reset spring, the ratchet pawl mechanism The wheel ratchet mechanism is connected between the inner end of the nonlinear coil spring and the lower end surface of the top cover of the frame body; each reset spring is always kept in a tensioned state, and is used to provide a force for the stop ratchet to approach the ratchet wheel; during the stiffness adjustment process of the nonlinear coil spring, the stop switch allows the ratchet wheel to move only in a set direction according to the instruction of the control unit, so that the number of working turns of the nonlinear coil spring increases or decreases, until the load torque, the torque of the nonlinear coil spring and the output torque of the drive motor are balanced, and the control unit controls the stop switch to lock the inner end of the nonlinear coil spring.

[0030] Further, the ratchet pawl mechanism comprises a ratchet shaft coaxial with the central axis and a ratchet wheel fixedly sleeved on the ratchet shaft, and a positive stop pawl and a negative stop pawl matched with the ratchet wheel through a tooth portion, the top end of the ratchet shaft is rotatably connected to the frame body, the inner end of the nonlinear coil spring is fixedly connected to the ratchet shaft, the ends of the positive stop pawl and the negative stop pawl away from their respective tooth portions are rotatably connected to the lower end surface of the top cover of the frame body, the positive return spring and the positive stop switch are provided between the end of the positive stop pawl close to its tooth portion and the lower end surface of the top cover of the frame body, and the negative return spring and the negative stop switch are provided between the end of the negative stop pawl close to its tooth portion and the lower end surface of the top cover of the frame body;

[0031] During the adjustment process of the nonlinear coil spring, at most only one of the two stop pawls cooperating with the ratchet wheel is in contact with the teeth of the ratchet wheel; when the load torque, the torque of the coil spring and the output torque of the drive motor are balanced, the two stop pawls cooperating with the ratchet wheel are both in contact with the teeth of the ratchet wheel.

[0032] In some embodiments, the elastic element is a nonlinear elastic element, which is composed of a first sub-coil spring and a second sub-coil spring connected in parallel through the stiffness adjustment component and having the same number of working turns, the first sub-coil spring is arranged closer to the central axis than the second sub-coil spring, each sub-coil spring is a linear coil spring, or a nonlinear coil spring, or one of them is a linear coil spring and the other is a nonlinear coil spring; the nonlinear coil spring is a planar spiral spring formed by a plurality of coil spring segments connected end to end in sequence and integrally formed, and the stiffness of two adjacent coil spring segments is different; the stiffness adjustment component includes a first stiffness adjustment mechanism and a second stiffness adjustment mechanism, and a partition fixedly connected to the frame body is provided in the frame body;

[0033] The first stiffness adjustment mechanism includes a first sub-coil spring locking piece and a first sub-coil spring fixing frame, the first stiffness adjustment mechanism and the first sub-coil spring are located on the side of the partition facing the central axis, the second stiffness adjustment mechanism includes a second sub-coil spring locking piece and a second sub-coil spring fixing frame, the second stiffness adjustment mechanism and the second sub-coil spring are located on the side of the partition facing away from the central axis; each sub-coil spring locking piece includes a ratchet pawl mechanism and a matching stop switch and a reset spring, each ratchet pawl mechanism shares a ratchet shaft, the ratchet shaft is coaxial with the central axis and fixedly connected and rotatably connected to the frame body, the first ratchet pawl mechanism is connected to the first A second ratchet pawl mechanism is connected between the outer end of a sub-coil spring and the lower end surface of the partition, and between the outer end of the second sub-coil spring and the lower end surface of the top cover of the frame body; each reset spring is always kept in a compressed state, and is used to provide a force for the corresponding stop pawl to approach the direction of each ratchet; in the process of adjusting the elastic element, each stop switch allows each ratchet to move only in the same set direction according to the instruction of the control unit, so that the working turns of the two sub-coil springs are increased or decreased, until the load torque, the torque of the elastic element and the output torque of the drive motor are balanced, and the control unit controls the corresponding stop switch to lock the outer ends of the two sub-coil springs.

[0034] Furthermore, the nonlinear elastic element is designed according to the following steps:

[0035] Divide the given working curve of the adaptive driving module into S segments, wherein the working curve of the adaptive driving module is a functional relationship between the rotation angle of the central axis and the torque output through the external terminal;

[0036] Assume that the number of coil segments contained in the first sub-coil spring is P, and the number of coil segments contained in the second sub-coil spring is Q, and both P and Q are positive integers greater than or equal to 1, and satisfy S≥P, S≥Q. When the number of coil segments of the sub-coil spring is 1, the sub-coil spring is a linear coil spring, and when the number of coil segments of the sub-coil spring is greater than 1, the sub-coil spring is a nonlinear coil spring;

[0037] For the i-th section of the working curve, i=1,2,...,S, the torque at a certain rotation angle φ on the section of the working curve is taken as the sum of the torque of the first sub-coil spring and the torque of the second sub-coil spring at the rotation angle φ, and the slope of the working curve at the rotation angle φ is taken as the sum of the stiffness of the first sub-coil spring and the stiffness of the second sub-coil spring at the rotation angle φ, thereby obtaining the respective working curves of the first sub-coil spring and the second sub-coil spring within the rotation angle range corresponding to the i-th section of the working curve;

[0038] According to the working curves of the first sub-coil spring and the second sub-coil spring, each coil spring segment in the first sub-coil spring and the second sub-coil spring is designed according to the industry standard JB / T7366-1994, and the parameters of each coil spring segment are obtained, including elastic modulus E, cross-sectional thickness h, cross-sectional width b and unfolded length l.

[0039] Further, the first ratchet pawl mechanism includes a first ratchet rotatably sleeved on the ratchet shaft and a first positive stop pawl and a first negative stop pawl matched with the first ratchet through a tooth portion, a first sub-coil spring fixing frame integrally formed with the first ratchet is provided on the outer periphery of the first ratchet, an inner end and an outer end of the first sub-coil spring are respectively fixedly connected to the ratchet shaft and the first sub-coil spring fixing frame, an end of the first positive stop pawl and the first negative stop pawl away from their respective tooth portions are rotatably connected to an end surface of the partition facing the first sub-coil spring fixing frame, a first positive return spring and a first positive stop switch are provided between an end of the first positive stop pawl close to its tooth portion and the partition, and a first negative return spring and a first negative stop switch are provided between an end of the first negative stop pawl close to its tooth portion and the partition;

[0040] The second ratchet pawl mechanism comprises a second ratchet wheel rotatably sleeved on the ratchet shaft and a second positive stop pawl and a second negative stop pawl which cooperate with the second ratchet wheel through a tooth portion, a second sub-coil spring fixing frame which is integrally formed with the second ratchet wheel is provided on the outer periphery of the second ratchet wheel, an inner end and an outer end of the second sub-coil spring are respectively fixedly connected to the second ratchet shaft and the second sub-coil spring fixing frame, an end of the second positive stop pawl and the second negative stop pawl which are away from their respective tooth portions are rotatably connected to an end surface of the top cover of the frame body facing the second sub-coil spring fixing frame, a second positive return spring and a second positive stop switch are provided between an end of the second positive stop pawl which is close to its tooth portion and the top cover of the frame body, and a second negative return spring and a second negative stop switch are provided between an end of the second negative stop pawl which is close to its tooth portion and the top cover of the frame body;

[0041] During the adjustment process of the elastic element, at most only one of the two stop pawls matching the same ratchet wheel is in contact with the teeth of the ratchet wheel; when the load torque, the torque of the elastic element and the output torque of the drive motor are balanced, the two stop pawls matching the same ratchet wheel are both in contact with the teeth of the ratchet wheel.

[0042] Furthermore, after the torque is balanced, if the carrier is required to continue to rotate an angle α along the original rotation direction due to the need of the working angle, the two stop pawls cooperating with each ratchet are first placed in a state opposite to that before the torque is balanced, so that the outer end of each sub-winding spring rotates an angle α, and the inner end of each sub-winding spring will follow the outer end of the sub-winding spring to rotate an angle α, and then the stop pawls are used to make each ratchet in a bidirectional locking state;

[0043] After the torque is balanced, if the carrier is required to rotate an angle β in the opposite direction of the original rotation direction due to the need of the working angle, the two stopping pawls cooperating with each ratchet wheel are first placed in the same state as before the torque is balanced, and the driving motor is used to drive the carrier to rotate in the opposite direction of the original rotation direction to unload each sub-coil spring. Until the elastic torque of each sub-coil spring is zero, the driving motor is used to drive the carrier to continue to rotate an angle β in the opposite direction of the original rotation direction, thereby pushing the outer end of each sub-coil spring to rotate an angle β in the opposite direction of the original rotation direction of the carrier. At this time, the stopping pawl is first used to make each ratchet wheel in a two-way locking state, and then the two stopping pawls cooperating with each ratchet wheel are placed in the same state as before the torque is balanced, the load torque is connected, the inner end of each sub-coil spring rotates in the original rotation direction of the carrier, each sub-coil spring is compressed and deformed, and the outer end of each sub-coil spring rotates in the opposite direction of the original rotation direction of the carrier by an angle β, so that the torque is balanced again, and finally the stopping pawl is used to make each ratchet wheel in a two-way locking state.

[0044] In some embodiments, the control unit includes a circuit board and a main controller, an angle sensor and a current sensor arranged on the circuit board, the circuit board is fixedly connected to the frame body, the angle sensor is used to measure the angle of the central shaft in real time, the current sensor is used to measure the current of the drive motor in real time, and the main controller is used to control the drive motor and each stop switch according to the angle signal of the central shaft and the current signal of the drive motor.

[0045] In some embodiments, the backpack system further includes a handle matched with the gear and a power module connected to the drive motor, so that the backpack system has a manual power generation function;

[0046] When manual power generation is required, the mover frame together with the adaptive drive module and the package body thereon are detached from the upper part of the stator frame, and the control unit controls each stop switch to separate all the stop pawls from the teeth of the corresponding ratchet wheels. The gear is rotated by the handle to generate current for the drive motor, which is stored in the power module.

[0047] In some embodiments, the control unit is also used to perform four-loop control on the drive motor according to the acceleration of the mover frame, so that the mover frame and the package are maintained at the target position while adaptively adjusting the size of different step frequencies, and the step frequency size is equivalent to the oscillation frequency of the acceleration of the mover frame; the four-loop control is to add an acceleration loop on the basis of the FOC method, and the acceleration loop is used to fit the deviation between the current position of the mover frame and its target position through a PID control algorithm according to the deviation between the current acceleration of the mover frame and its target acceleration, and obtain the target angle of the drive motor according to the deviation of the target position, and use the target angle as the input of the FOC method. After calculation by the FOC method, the target current value of the drive motor to maintain or reach the target angle is obtained.

[0048] Compared with the prior art, the present invention has the following characteristics and beneficial effects:

[0049] (1) The adaptive suspension backpack system of the present application can automatically adjust the system stiffness according to different loads or step frequencies, and is suitable for scenarios with different loads and step frequencies; wherein, for different loads, the stiffness adjustment component adjusts the stiffness of the nonlinear elastic element by controlling the engagement of the pawls or the contact of the friction wheels in the stiffness adjustment component according to the instructions issued by the control unit, so as to automatically adapt to various load sizes; for different step frequencies, the drive motor is closed-loop controlled by the acceleration of the mover frame collected in real time, so as to automatically adapt to various step frequencies;

[0050] (2) The adaptive suspension backpack system of the present application adopts a lightweight design, with exquisite design and light weight; the adaptive drive module has a large stiffness adjustment range, the built-in nonlinear elastic element is small, the stiffness adjustment component is simple, the volume occupied is small, and the weight is comparable to that of an ordinary drive; the coaxial arrangement between the nonlinear elastic element, the stiffness adjustment component and the control unit makes the drive module compact, low power consumption and simple to control; the introduction of the nonlinear elastic element enables the drive module to simultaneously meet the rotation angle requirements of the carrier and the torque requirements of the elastic element under compact space constraints;

[0051] (3) The adaptive suspension backpack system of the present application is convenient to adjust stiffness. It only needs to preload the nonlinear elastic element until the mover frame does not separate from the stator frame. The coil spring will automatically adjust to a stiffness that matches the load size during operation.

[0052] (4) The adaptive suspension backpack system of the present application can be switched to manual power generation. The mover frame is removed and the handle is inserted to use the drive motor to generate electricity. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 This is a front and side view of an adaptive suspension load-reducing backpack system provided in an embodiment of the present disclosure, in which the bag body is omitted.

[0054] Figure 2 This is a rear view of an adaptive suspension load-reducing backpack system provided in an embodiment of the present disclosure, in which the bag body is partially cropped.

[0055] Figure 3 An exploded diagram of an adaptive suspension load-reducing carrying system provided in an embodiment of the present disclosure, in which the enclosure is omitted.

[0056] Figure 4a This is a schematic diagram of the assembly relationship between a back frame unit and a transmission unit in an adaptive suspension load-reducing back system provided by an embodiment of the present disclosure.

[0057] Figure 4b A schematic structural diagram of a guide module in an adaptive suspension load-reducing backpack system provided in an embodiment of the present disclosure.

[0058] Figure 5 a. Figure 5 b. Figure 5 c are schematic diagrams of a locking mechanism in a back frame unit of an adaptive suspension load-reducing back system and its locked and unlocked states provided in an embodiment of the present disclosure.

[0059] Figure 6 A schematic diagram of the assembly relationship between a transmission unit and an adaptive drive module in an adaptive suspension load-reducing backpack system provided in an embodiment of the present disclosure.

[0060] Figure 7 A schematic structural diagram of a series drive module used in an adaptive suspension load-reducing backpack system provided in an embodiment of the present disclosure.

[0061] Figure 8 for Figure 7 A schematic longitudinal section diagram of a series drive module is shown.

[0062] Fig. 9 for Figure 7 The exploded view of the drive unit in the series drive module is shown.

[0063] Fig.10 for Figure 7 The explosion diagram of the series variable stiffness unit in the series drive module shown in the first perspective.

[0064] Fig.11for Figure 7 The explosion diagram of the series variable stiffness unit in the series drive module shown in the second perspective.

[0065] Fig.12 (a), (b), and (c) are schematic diagrams of the working process of the stiffness adjustment component of the series variable stiffness unit in the series drive module.

[0066] Fig.13 A schematic diagram of the structure of a parallel drive module used in an adaptive suspension load-reducing backpack system provided in an embodiment of the present disclosure.

[0067] Fig.14 for Fig.13 A schematic longitudinal section diagram of a parallel drive module is shown.

[0068] Fig.15 for Fig.13 The explosion diagram of the parallel variable stiffness unit in the parallel drive module shown in the first perspective.

[0069] Fig.16 for Fig.13 The explosion diagram of the parallel variable stiffness unit in the parallel drive module shown in the second perspective.

[0070] Fig.17 (a), (b), and (c) are schematic diagrams of the working process of the stiffness adjustment component of the series variable stiffness unit in the parallel drive module.

[0071] Fig.18 A schematic longitudinal section diagram of a single coil spring drive module used in an adaptive suspension load-reducing backpack system provided in an embodiment of the present disclosure.

[0072] Fig.19 for Fig.18 The explosion diagram of the variable stiffness unit in the single coil spring drive module is shown in the first perspective.

[0073] Fig. 20 for Fig.18 The explosion diagram of the variable stiffness unit in the single coil spring drive module shown in the second perspective.

[0074] In the figure:

[0075] A is the back frame unit, A1 is the mover frame, A11 is the first hole position, A2 is the stator frame, A21 is the shoulder strap, A22 is the side edge, A3 is the guide module, A31a is the horizontal guide rail, A31b is the vertical guide rail, A32 is the guide wheel assembly, A32a is the horizontal guide wheel, A32b is the vertical guide wheel, A33a is the horizontal guide wheel shaft, A33b is the vertical guide wheel shaft, A34 is the bolt, A41 is the first limit block, A42 is the second limit block, A5 is the locking mechanism, A51 is the lock plug, A52 is the lock plug shaft, A53 is the gasket, A54 is the screw, A55 is the lock hook, and A56 is the lock hook shaft;

[0076] B is the inclusion body;

[0077] C is the transmission unit, C1 is the rack, C2 is the gear, C3 is the auxiliary gear, and C4 is the auxiliary gear shaft;

[0078] D is the adaptive drive module;

[0079] E is the handle;

[0080] F is the power module;

[0081] 100 is a frame, 110 is a frame body, 111 is an upper shell, 1111 is a second boss, 1112 is a third boss, 111a is a partition, 112 is a lower shell, 1121 is a second journal, and 120 is an external connection end;

[0082] 200 is a driving unit, 210 is a central shaft, 220 is a driving motor, 221 is a rotor frame, 2211 is a first journal, 222 is a magnetic steel, 223 is a winding frame, 224 is a coil, 230 is a reducer, 231 is a planetary frame, 231a is a bolt hole, 2311 is a planetary frame body, 2311a is a planetary shaft, 2312 is a planetary frame top cover, 232 is a sun gear, 233 is a planetary gear, and 234 is an inner gear ring;

[0083] 300 is a series variable stiffness unit, 310 is a nonlinear elastic element, 311 is a first sub-coil spring, 312 is a second sub-coil spring, 320 is a stiffness adjustment component, 321 is a first sub-coil spring locking member, 3211 is a first ratchet, 3212 is a first positive stop pawl, 3213 is a first negative stop pawl, 3214 is a first positive return spring, 3215 is a first positive stop switch, 3216 is a first negative return spring, 3217 is a first negative stop switch, 322 is a first sub-coil spring driving frame, 3221 is a third journal, 3222 is a set screw, 3223 is a first shaft pin, 323 is a second sub-coil spring locking member, 3231 is a second ratchet, 3232 is a second positive stop pawl, 3233 is a second negative stop pawl, 3234 is a second positive return spring, 3235 is a second positive stop switch, 3236 is a second negative return spring, 3237 is a second negative stop switch, 324 is a second sub-coil spring driving frame, 3241 is a first boss, 3242 is a second shaft pin, 325 is a ratchet shaft, 3251 is an upper bearing bush, and 3252 is a lower bearing bush;

[0084] 300' is a parallel type variable stiffness unit, 310' is a nonlinear elastic element, 311' is a first sub-coil spring, 312' is a second sub-coil spring, 320' is a stiffness adjustment component, 321' is a first sub-coil spring locking member, 3211' is a first ratchet, 3212' is a first positive stop pawl, 3213' is a first negative stop pawl, 3214' is a first positive return spring, 3215' is a first positive stop switch, 3216' is a first negative return spring, 3217' is a first negative stop switch, 3218' is a set screw, and 3219' is a first bearing , 322' is a first sub-coil spring fixing frame, 3221' is a first shaft pin, 323' is a second sub-coil spring locking member, 3231' is a second ratchet, 3232' is a second positive stop pawl, 3233' is a second negative stop pawl, 3234' is a second positive return spring, 3235' is a second positive stop switch, 3236' is a second negative return spring, 3237' is a second negative stop switch, 3238' is a second ratchet shaft, 3239' is a second bearing, 324' is a second sub-coil spring fixing frame, 3241' is a second shaft pin, and 325' is a ratchet shaft;

[0085] 300* is a single coil spring drive module, 310* is a nonlinear coil spring, 320* is a stiffness adjustment component, 321* is a coil spring locking member, 3210* is a ratchet, 3211* is a pin, 3212* is a first set screw, 3213* is a positive stop pawl, 3214* is a negative stop pawl, 3215* is a positive return spring, 3216* is a positive stop switch, 3217* is a negative return spring, 3218* is a negative stop switch, 322* is a coil spring drive frame, 3221* is a third journal, 3222* is a second set screw, 3223* is a second pin, and 323* is a coil spring adjustment motor;

[0086] 400 is a control unit, 410 is a circuit board, and 420 is a dust cover;

[0087] a is the first bearing, b is the second bearing, c is the third bearing, d is the fourth bearing, e is the fifth bearing, f is the sixth bearing, and g is the seventh bearing. DETAILED DESCRIPTION

[0088] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0089] In order to better describe and illustrate the embodiments of the present application, reference may be made to one or more drawings, but the additional details or examples used to describe the drawings should not be considered as limiting the scope of the invention of the present application, any of the currently described embodiments or preferred methods.

[0090] It should be noted that when a component is referred to as being "connected" to another component, it may be directly connected to the other component or there may be a central component. When a component is referred to as being "disposed on" another component, it may be directly disposed on the other component or there may be a central component at the same time.

[0091] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0092] See also Figure 1 to Figure 3 , an adaptive suspension load-reducing carrying system provided by an embodiment of the present disclosure includes a back frame unit A, a bag body B, a transmission unit C and an adaptive driving module D;

[0093] The back frame unit A includes a mover frame A1, a stator frame A2 and a guide module A3. The guide module A3 is connected between the mover frame A1 and the stator frame A2 and is used to limit the mover frame A1 to only move along the cross-sectional normal direction of the back system relative to the stator frame A2 (i.e. Figure 1 The stator frame A2 is provided with a shoulder strap A21 on the side facing away from the mover frame A1;

[0094] The package body B is fixedly connected to the side of the mover frame A1 facing away from the stator frame A2;

[0095] The transmission unit C is arranged between the mover frame A1 and the stator frame A2, and includes a rack C1 and a gear C2 meshed by teeth, and the rack C1 is arranged along the cross-section normal of the carrying system and is fixedly connected to the stator frame A2;

[0096] The adaptive drive module D includes a frame and a drive unit, a variable stiffness unit and a control unit arranged in the frame; wherein,

[0097] The frame includes a frame body fixedly connected to the side of the mover frame A1 facing away from the stator frame A2 and an external connection end 120 arranged on the frame body. The external connection end 120 passes through the first hole A11 on the mover frame A1 and is fixedly connected to the gear C2. The load of the package B transmitted by the transmission unit C is connected through the external connection end 120, and the power provided by the driving unit is transmitted to the mover frame A1 and the package B.

[0098] The driving unit includes a coaxially arranged central shaft and a driving motor, and the output of the driving motor drives the central shaft to rotate, and then is connected to the external connection end 120 through a reducer;

[0099] A variable stiffness unit, comprising an elastic element and a stiffness adjustment component, wherein the stiffness adjustment component is connected to the elastic element and the central axis of the driving unit, the load torque is transmitted to the stiffness adjustment component via the reducer and the central axis, and then the torque is applied to one end of the elastic element, the stiffness adjustment component changes the number of working turns and output torque of the elastic element by unidirectional or bidirectional locking of one end of the elastic element, thereby balancing the corresponding load torque, and the stiffness adjustment component adjusts the initial angle of the elastic element by pre-tightening or unloading the other end of the elastic element, and the initial angle of the elastic element corresponds to the initial position of the mover frame A1 relative to the stator frame A2;

[0100] The control unit is used to control the stiffness adjustment component and the drive motor according to the current signal of the drive motor and the rotation angle signal of the central shaft, so as to achieve a balance among the load torque, the torque of the elastic element and the output torque of the drive motor, and realize adaptive adjustment of different load sizes while providing power to the mover frame A1 and the package B to maintain the target position.

[0101] In some embodiments, see Figure 4a The back frame unit A serves as the skeleton of the back system of the embodiment of the present disclosure, and is mainly used to realize the installation of other components in the back system of the embodiment of the present disclosure. The mover frame A1 and the stator frame A2 in the back frame unit A are made of lightweight materials such as nylon and high-strength resin that meet the mechanical strength requirements, and are designed to be hollowed out to further reduce their own weight. The side of the stator frame A2 facing the back of the human body (i.e., the side facing away from the mover frame A1) is designed to be arc-shaped to meet ergonomic requirements. Three side edges A22 that cooperate with the guide module A3 are formed at equal intervals on the side of the stator frame A2 facing the mover frame A1, and the axial direction of each side edge A22 is parallel to the normal of the cross section of the back system, two of which are arranged on the left and right sides of the stator frame A2, and the other side edge is located in the center of the stator frame A2.

[0102] In some embodiments, see Figure 4a , 4b The guide module A3 in the back frame unit A is used to limit the direction of movement of the mover frame A1 relative to the stator frame A2, so that the mover frame A1 can only move in the up and down direction relative to the stator frame A2. Optionally, the guide module A3 includes two L-shaped guide rails arranged on the left and right sides of the mover frame A1 and integrally formed with the mover frame A1, and a plurality of guide wheel groups installed on the side of the stator frame A2 facing the mover frame A1, and the horizontal section and the vertical section of each L-shaped guide rail are used as the horizontal guide rail A31a and the vertical guide rail A31b respectively. In this embodiment, a total of 6 guide wheel groups A32 are provided, which are arranged in the form of 3 rows and 2 columns. Each column of guide wheel groups cooperates with a corresponding L-shaped guide rail. Each guide wheel group consists of 2 horizontal guide wheels A32a and 1 vertical guide wheel A32b. The 2 horizontal guide wheels A32a are arranged on the front and rear sides of the horizontal guide rail A31a (to limit the horizontal guide rail A31a from moving forward and backward) and are rotatably mounted on a corresponding horizontal guide wheel shaft A33a. Each horizontal guide wheel shaft A33a is fixed to the side edge A22 of the corresponding side of the stator frame A2 by a bolt A34; a vertical guide wheel A32b is located on the inner side of the vertical guide rail A31b and is rotatably mounted on a vertical guide wheel shaft A33b. The vertical guide wheel shaft A33b is fixed to the stator frame A2 by a bolt A34. During the movement of the mover frame A1 relative to the stator frame A2, the horizontal guide wheel A32a and the horizontal guide rail A31a generate rolling friction to constrain the movement of the mover frame A1 in the normal direction of the coronal plane of the backpack system (i.e., the front-to-back direction), and the vertical guide wheel A32b and the vertical guide rail A31b generate rolling friction to constrain the movement of the mover frame A1 in the normal direction of the sagittal plane of the backpack system (i.e., the left-to-right direction). Therefore, the mover frame A1 can only move in the up and down directions.

[0103] Furthermore, in order to ensure that the mover frame A1 does not separate from the stator frame A2 during the load-bearing process, a limiting member is provided on the side of the mover frame A1 and the stator frame A2 that are arranged opposite to each other. Specifically, a first limiting block A41 is provided on the upper end of the mover frame A1 facing the stator frame A2 (the first limiting block is Figure 3 As shown in the figure, a second limit block A42 is provided at a corresponding position on the central side edge A22 of the stator frame A2. When the mover frame A1 moves to the lowest part relative to the stator frame A2, the top surface of the second limit block A42 contacts the bottom surface of the first limit block A41, so that the mover frame A1 will not separate from the stator frame A2.

[0104] Further, see Figure 3 , Figure 4a , Figure 5 In (a) to (c), a locking mechanism A5 is further provided between the mover frame A1 and the stator frame A2. The locking mechanism A5 has two states: locked and unlocked. When the locking mechanism A5 is in the locked state, the mover frame A1 cannot move relative to the stator frame A2. At this time, the carrying system is the same as an ordinary backpack and has no load-reducing effect. When the locking mechanism A5 is in the unlocked state, the mover frame A1 can move relative to the stator frame A2. Specifically, the locking mechanism A5 is arranged near the lower part of the stator frame A2, and includes two locking modules which are symmetrically arranged about the central side edge of the stator frame A2 and have the same structure, and each locking module includes a locking plug A51 and a locking hook A55; the locking plug A51 is a Z-shaped sheet structure, and the locking plug A51 is rotatably mounted on a locking plug shaft A52 fixedly connected to the stator frame A2; the locking hook A55 is an L-shaped sheet structure, and the locking hook A55 is rotatably mounted on a locking hook shaft A56 fixedly connected to the central side edge of the stator frame A2, and a first slot A53 is provided on the locking hook A55, which cooperates with the end of the locking plug A51, and a second slot A54 is provided at the lower part of the side of the mover frame A1 facing the stator frame A2, which cooperates with the end of the locking hook A55 away from the locking hook shaft A56. When the stator frame A2 and the mover frame A1 need to be locked, the lock hook A55 is first rotated to insert one end of the lock hook A55 into the second slot A54 of the mover frame A1, and then the lock plug A51 is rotated to insert one end of the lock plug A51 into the first slot A53 of the lock hook A55, so that the lock hook A55 cannot rotate relative to the lock hook shaft A56, and the mover frame A1 cannot move corresponding to the stator frame A2 under the restriction of the lock hook A55, thereby achieving the locking of the mover frame A1 and the stator frame A2. Conversely, when the mover frame A2 and the stator frame A1 need to be unlocked, the lock plug A51 is first rotated to disengage one end of the lock plug A51 from the first slot A53 of the lock hook A55, and then the lock hook A55 is rotated to disengage one end of the lock hook A55 from the second slot A54 of the mover frame A1, thereby unlocking the mover frame A1 and the stator frame A2.

[0105] In some embodiments, see Figure 4a , Figure 6 , the rack C1 in the transmission unit C is fixedly connected to the central side edge A22 on the stator frame A2, and is located between the second limit block A42 and the locking mechanism A5. The gear C2 is located on the left side of the rack C1, and the gear C2 is coaxially arranged with the external end of the adaptive drive module D, and the gear C2 moves synchronously with the external end of the adaptive drive module D. Furthermore, in order to ensure the transmission efficiency between the gear C2 and the rack C1 (for example, when there is a gap between the gear C2 and the rack C1, resulting in a lack of close contact, the transmission efficiency will be reduced), an auxiliary gear C3 is also provided on the right side of the rack C1, and the auxiliary gear C3 is rotatably sleeved on the auxiliary gear shaft C4 fixed to the side of the mover frame A1 facing the stator frame A2.

[0106] In some embodiments, the bag B is used to load heavy objects. It should be noted that in order not to increase the size of the carrying system in the front-to-back direction too much, the remaining components of the adaptive drive module D except the connection end are placed in the bag B in this embodiment.

[0107] The adaptive drive module D is the core component of the carrying system provided by the present disclosure, which can realize adaptive adjustment for different load sizes or step frequencies, and finally achieve the effect of reducing the load. The present disclosure provides three implementation methods of the adaptive drive module D, namely, a series drive module I, a parallel drive module II and a single coil spring drive module III. The elastic elements used in the three drive modules are all nonlinear elastic elements, specifically nonlinear coil springs. Compared with the existing drive modules using linear springs as elastic elements, the use of nonlinear coil springs can achieve a larger central axis rotation angle range and coil spring torque range under the same spatial constraints. Specifically, compared with the existing linear coil springs with smaller stiffness, the nonlinear coil spring can withstand a larger load torque under the same coil spring outer diameter and number of rotations; compared with the existing linear coil springs with larger stiffness, the nonlinear coil spring can make the central axis rotate more times under the same coil spring outer diameter and load torque, thereby making the drive module. The rotation of the central axis in the adaptive drive module of this embodiment is converted into the linear motion of the mover frame A1 through the external terminal 120 and the transmission unit C, and the torque of the coil spring is converted into the load size through the external terminal 120 and the transmission unit C. Therefore, for the carrying system, compared with the linear coil spring with smaller stiffness, the nonlinear coil spring can bear a larger load under the same coil spring outer diameter and the linear reciprocating displacement of the mover frame; compared with the linear coil spring with larger stiffness, the nonlinear coil spring can make the linear reciprocating displacement of the mover frame larger under the same coil spring outer diameter and load. The three structural forms of the adaptive drive module will be described in detail below in conjunction with the accompanying drawings.

[0108] 1. Series drive module Ⅰ

[0109] See also Figure 7 , Figure 8 (It should be noted that Figure 7 , Figure 8 The up and down directions shown correspond to Figure 1 The rear and front of the frame), the series drive module I, includes a frame 100, and a drive unit 200, a series variable stiffness unit 300 and a control unit 400 arranged in the frame 100; wherein,

[0110] The frame 100 includes a frame body 110 and an external connection terminal 120 disposed on the frame body 110. The frame body 110 is fixedly connected to a side of the mover frame A1 facing away from the stator frame A2 by bolts. The load transmitted by the transmission unit D (the load mainly includes the weight of the package B and its internal weight, and the sum of the weight of the mover frame A1 and the components installed on the mover frame A1) is connected through the external connection terminal 120, and the power provided by the drive unit 200 is transmitted to the mover frame A1 and the package B;

[0111] The driving unit 200 includes a central shaft 210 and a driving motor 220 which are coaxially arranged, and the driving motor 220 drives the central shaft 210 to rotate, and then is connected to the external connection end 120 through a reducer 230;

[0112] The series variable stiffness unit 300 includes a nonlinear elastic element 310 and a stiffness adjustment component 320. The nonlinear elastic element 310 is composed of a first sub-coil spring 311 and a second sub-coil spring 312 connected in series through the stiffness adjustment component 320. The stiffness adjustment component 320 is also connected to the central shaft 210. The load torque is transmitted to the stiffness adjustment component 320 through the reducer 230 and the central shaft 210, and then the torque is applied to the outer end of the nonlinear elastic element 310. The stiffness adjustment component 320 changes the working number of turns and the output torque of the nonlinear elastic element 310 by unidirectional or bidirectional locking of the inner end of the nonlinear elastic element 310, so as to balance the corresponding load torque. The stiffness adjustment component 320 pre-tightens or unloads the inner end of the nonlinear elastic element 310 to adjust the initial angle of the inner end of the nonlinear elastic element 310. The initial angle of the inner end of the nonlinear elastic element 310 corresponds to the initial position of the mover frame A1 relative to the stator frame A2.

[0113] The control unit 400 is used to control the stiffness adjustment component 320 and the drive motor 220 according to the current signal of the drive motor 220 and the fluctuation of the rotation angle of the central axis 210, so as to achieve a balance among the load torque, the torque of the nonlinear elastic element 310 and the output torque of the drive motor 220 (hereinafter the output torque of the drive motor is referred to as "drive torque"), thereby providing power to the mover frame A1 and the package B to maintain the target position and realizing adaptive adjustment of different load sizes.

[0114] Further, the frame body 110 is used as a base to provide support and positioning for other components in the serial drive module of this embodiment. Optionally, the frame body 110 includes an upper shell 111 and a lower shell 112 that are fixedly connected by bolts and coaxially arranged with the central axis 210. The drive motor 220 and the central axis 210 are both located in the lower shell 112, and the upper end of the central axis 210 protrudes from the upper end surface of the lower shell 112. The external terminal 120 is rotatably arranged at the center of the lower end surface of the lower shell 112 through a third bearing c. The serial variable stiffness unit 300 and the control unit 400 are both located in the upper shell 111.

[0115] Further, see Fig. 9 The drive motor 220 is used as the power source of the serial drive module of this embodiment to provide power for the mover frame A1 to maintain the target position. The drive motor 220 has an input shaft and an output shaft, and the input shaft and the output shaft are arranged on both sides of the drive motor body. In this embodiment, the drive motor 220 uses a brushless DC motor, which is different from the current commercially available motor in that its rotating central axis is used. The output shaft of the current commercially available motor is generally built into the motor housing, while in the embodiment of the present disclosure, the central axis 210 is used to replace the output shaft of the commercially available motor, which is convenient for connection with the serial variable stiffness unit 300. Most of the central axis 210 is located in the drive motor 220, and the top of the central axis 210 protrudes from the top of the drive motor 220. The drive motor 220 of this embodiment includes a rotor frame 221 and a magnetic steel 222, a winding frame 223 and a coil 224 located in the rotor frame 221. The magnetic steel 222 is fixed to the inner wall of the rotor frame 221, and the coil 224 is wound on the winding frame 223. A first journal 2211 with a through hole is formed at the center of the upper end surface of the rotor frame 221. The first journal 2211 partially protrudes from the upper end surface of the rotor frame 221 and partially is located inside the rotor frame 221. The outer side wall of the first journal 2211 protruding from the upper end surface of the rotor frame 221 is rotatably connected to the inner side wall of the second journal 1121 at the center of the upper end surface of the lower shell 112 through the first bearing a. The outer side wall of the first journal 2211 located inside the rotor frame 221 is rotatably connected to the planetary carrier top cover 2312 through the second bearing b. At the same time, the external connection end 120 is also rotatably connected to the lower end of the lower shell 112 through the third bearing c. When the coil 224 is energized, a magnetic field is generated. Under the action of the magnetic field, the magnet 222 rotates with the rotor frame 221, and the rotation of the rotor frame 221 drives the central shaft 210 circumferentially fixed thereto to rotate synchronously. One end of the central shaft 210 is a gear (the gear is the sun gear 232 in the reducer 230), which then drives the external end 120 to rotate through the reducer 230 to achieve external power output.

[0116] See also Fig.10The reducer 230 disposed between the output end of the driving motor 220 and the external connection end 120 is used to reduce the rotation speed of the output end of the driving motor 220 to amplify the output torque. The output end of the driving motor 220 is the central shaft 210, and the gear 232 at one end thereof is the high-speed input end of the reducer 230, and the low-speed output end of the reducer 230 is the external connection end 120. When the load torque changes little over time during use, the torque generated by the driving motor 220 is sufficient to overcome the change in the load torque. At this time, it is not necessary to reduce the motor speed to amplify the output torque, and the reducer 230 can be omitted. The reducer 230 of this embodiment is a planetary gear reducer, including an inner ring gear 234, a planet carrier 231, a sun gear 232 and a plurality of planetary gears 233; the inner ring gear 234 is fixedly connected to the lower shell 112 and meshes with the inner surface of each planetary gear 233; the planet carrier 231 includes a planet carrier body 2311 and a planet carrier top cover 2312 that are fixedly connected, the planet carrier body 2311 is the external connection end 120, and the planet carrier body 2311 is provided with a plurality of planetary gears 232 and a plurality of planetary gears 233; The planetary gears 233 are respectively sleeved on the corresponding planetary shafts 2311a through the fourth bearing d, and each planetary gear 233 is meshed with the sun gear 232 fixed to one end of the central shaft 210. The central shaft 210 is used as the axle of the sun gear 232 and is integrally formed with the sun gear 232. The planetary carrier body 2311 and the planetary carrier top cover 2312 are provided with a plurality of bolt holes 231a, and the two are fixedly connected by bolts to form the planetary carrier 231. In addition to the planetary gear reducer, the reducer 230 includes other types of reducers such as but not limited to RV reducers, cycloid reducers or harmonic gear reducers, which are not given examples and repeated here.

[0117] Further, see Fig.11 , Fig.12 In the series variable stiffness unit 300 of this embodiment, the nonlinear elastic element 310 is composed of two sub-coil springs connected in series in sequence, each sub-coil spring is arranged in layers in the upper shell 111 of the frame body 110, and the first sub-coil spring 311 is arranged closer to the central axis 210 than the second sub-coil spring 312. Each sub-coil spring is a linear coil spring, or a nonlinear coil spring, or one of them is a linear coil spring and the other is a nonlinear coil spring; the nonlinear coil spring is a plane spiral spring formed by connecting multiple coil spring segments end to end and forming an integral body, and the stiffness of two adjacent coil spring segments is different. It is assumed that the first sub-coil spring 311 is provided with P coil spring segments, and the second sub-coil spring 312 is provided with Q coil spring segments, and P and Q are both positive integers greater than or equal to 1. When the number of segments of the sub-coil spring is 1, the sub-coil spring is a linear coil spring, and when the number of segments of the sub-coil spring is greater than 1, the sub-coil spring is a nonlinear coil spring. The nonlinear elastic element 310 is designed according to the following steps:

[0118] The working curve of the given series drive module is divided into S segments, and the number of segments S is determined according to the control accuracy of the carrier posture and the stiffness adjustment accuracy requirements. The higher the accuracy requirement, the larger the number of segments S is, and S is a positive integer greater than or equal to 2. The working curve of the series drive module is a functional relationship between the rotation angle (independent variable) of the central axis 210 and the torque (dependent variable) output through the external terminal 120. The determined number of segments S is used as the total number of segments of the nonlinear elastic element 310, that is, S=P+Q, and the first coil spring segment is located in the first sub-coil spring 311;

[0119] The i-th (i=1, 2, ..., S) working curve and its slope are respectively used as the working curve and stiffness of the i-th coil spring segment, and the i-th coil spring segment is designed according to the industry standard JB / T7366-1994 to obtain the parameters of the i-th coil spring segment, including elastic modulus E, cross-sectional thickness h, cross-sectional width b and unfolded length l. In this embodiment, the elastic modulus E, cross-sectional width b and unfolded length l of each coil spring segment are equal, and the nonlinear elastic element 310 meets the working curve requirements of the driving module by changing the cross-sectional thickness h of each coil spring segment, that is, the nonlinear coil spring in this embodiment is a plane scroll spring with a variable cross-sectional thickness. Similarly, the elastic modulus E, cross-sectional thickness h and unfolded length l of each coil spring segment can also be equal, and a plane scroll spring with a variable cross-sectional width b can be used.

[0120] It should be noted that the overall dimensions of each sub-coil spring in the free state obtained according to the above design steps should meet the set space requirements. If not, it needs to be redesigned.

[0121] It can be understood that since there is a proportional relationship between the displacement of the mover frame A1 and the rotation angle of the central axis 210 (the power transfer ratio of the reducer), and the initial rotation angle of the inner ring of the coil spring can be adjusted by the adjustment handle in the stiffness adjustment assembly 320 (the adjustment handle is not shown in the figure), in most applications, when the load angle range and the working torque relationship are required to meet the set function curve, even in a limited installation space, the nonlinear elastic element 310 that approximately meets the set function curve can still be designed according to the above steps.

[0122] Two linear coil springs with different stiffness are provided in the series drive module I. The linear coil spring with greater stiffness is used as the first sub-coil spring 311, and the linear coil spring with less stiffness is used as the second sub-coil spring 312 and arranged above the first sub-coil spring 311. The stiffness of the nonlinear elastic element 310 is obtained by connecting the first sub-coil spring 311 and the second sub-coil spring 312 in series. The first sub-coil spring 311 and the second sub-coil spring 312 with different stiffness can be selected and combined according to actual needs. At the same time, the first sub-coil spring 311 and the second sub-coil spring 312 are connected in series, so that the rotatable angle of the nonlinear elastic element 310 is increased, which can meet the needs of different scenarios.

[0123] In the serial variable stiffness unit 300 of this embodiment, a stiffness adjustment mechanism is respectively configured for each sub-coil spring, and the two stiffness adjustment mechanisms together constitute the stiffness adjustment assembly 320 in the serial variable stiffness unit 300 and are both coaxial with the central axis 210. Each stiffness adjustment mechanism is controlled by the control unit 400 to adjust the number of working turns of the coil spring. Specifically, each stiffness adjustment mechanism locks or unloads the corresponding sub-coil spring until the total elastic moment generated by the nonlinear elastic element 310 reaches the load moment and maintains balance. The first stiffness adjustment mechanism includes a first sub-coil spring locking member 321 and a first sub-coil spring driving frame 322, and the second stiffness adjustment mechanism includes a second sub-coil spring locking member 323 and a second sub-coil spring driving frame 324. Under normal working conditions, the first stiffness adjustment mechanism remains locked, so that the first sub-coil spring 311 and the second sub-coil spring 312 are connected end to end and remain in a series state. Specifically, the inner circle of the first sub-coil spring 311 is locked with the second sub-coil spring driving frame 324 through the first sub-coil spring locking member 321, thereby transmitting the torque to the outer circle of the second sub-coil spring 312. A (hexagonal) square hole is provided at the top of the central axis (i.e., the ratchet shaft 325) of the second sub-coil spring locking member 323, which can be rotated using an adjustment handle (not shown in the figure) to adjust the inner end angular position of the nonlinear elastic element 310. The angle difference between the inner end angular position and the outer end angular position of the nonlinear elastic element is the number of turns of the nonlinear elastic element 310 that are compressed. Different numbers of compressed turns will generate different elastic torques, and the nonlinear elastic element can be designed and manufactured using the above-mentioned design method for the nonlinear elastic element. The nonlinear elastic element 310 has the characteristic of adaptive load torque. In this embodiment, when the load is connected, the coil spring segments are compressed in order of stiffness from small to large according to the stiffness characteristics of each coil spring segment, that is, the coil spring segment with the smallest stiffness is compressed first. If the load torque is greater than the current coil spring torque, the coil spring segment with larger stiffness is compressed until balance is achieved.

[0124] In the stiffness adjustment assembly 320 of the series-type variable stiffness unit 300, the first sub-coil spring drive frame 322 is a circular plate with a third shaft neck 3221 at the center of the lower end surface, and the circular plate and the third shaft neck 3221 are both provided with a center hole matching the center axis 210, and the second sub-coil spring drive frame 324 is a circular plate with a center hole and a first boss 3241 is provided on the lower end surface of the circular plate, and a gap is left between the outer ends of the first sub-coil spring drive frame 322 and the second sub-coil spring drive frame 324 and the inner wall of the upper shell 111. The first sub-coil spring locking member 321 and the second sub-coil spring locking member 323 respectively include a ratchet pawl mechanism and a matching stop switch and a reset spring. The first sub-coil spring locking member 321 and the second sub-coil spring locking member 323 share a ratchet shaft 325, and the top end of the ratchet shaft 325 is rotatably connected to the frame body 110 through a fifth bearing e arranged at the center hole of the upper shell 111; an interface for inserting an adjustment handle (the adjustment handle is not shown in the figure) is also provided at the top end of the ratchet shaft 325, and the ratchet shaft 325 can be manually rotated by the adjustment handle. The third journal 3221 at the center of the first sub-coil spring driving frame 322 is fixedly sleeved on the top of the central shaft 210 by a set screw 3222, so as to rotate synchronously with the central shaft 210. The first sub-coil spring 311 is placed on the upper end surface of the first sub-coil spring driving frame 322, and the upper end surface of the first sub-coil spring driving frame 322 is provided with a first pin 3223 for fixing the outer end of the first sub-coil spring 311. The load torque passes through the first sub-coil spring driving frame 322, and the outer end of the first sub-coil spring 311 is rotated by the first sub-coil spring 311. The second sub-coil spring driving frame 324 is arranged above the first sub-coil spring 311, and the center of the second sub-coil spring driving frame 324 is tightly matched with the upper bearing 3251, and is rotatably mounted on the ratchet shaft 325 through the upper bearing 3251. The second sub-coil spring 312 is placed on the upper end surface of the second sub-coil spring driving frame 324, and the upper end surface of the second sub-coil spring driving frame 324 is provided with a second pin 3242 fixedly connected to the outer end of the second sub-coil spring 312.The ratchet pawl mechanism in the first sub-coil spring locking member 321 includes a first ratchet 3211 rotatably mounted on the ratchet shaft 325 through a lower bearing bush 3252, and a first positive stop pawl 3213 and a first negative stop pawl 3212 matched with the first ratchet 3211 through teeth. The lower bearing bush 3252 is tightly matched with the first ratchet 3211, and the lower end surface of the lower bearing bush 3252 is fixedly connected to the upper end surface of the first sub-coil spring driving frame 322. A ratchet wheel 3211 is rotatably connected to the lower bearing bush 3252, the inner end of the first sub-coil spring 311 is fixedly connected to the first ratchet wheel 3211, and there is relative rotation between the first ratchet wheel 3211 and the first sub-coil spring driving frame 322; one end of the first positive stop pawl 3213 and the first negative stop pawl 3212 are both rotatably connected to the first boss 3241 of the second sub-coil spring driving frame 324, and the first positive stop pawl 3213 is close to the first boss 3241 of the second sub-coil spring driving frame 324. A first positive return spring 3216 and a first positive stop switch 3217 are provided between one end of the tooth portion and the first boss 3241 of the second sub-coil spring driving frame 324, and a first negative return spring 3214 and a first negative stop switch 3215 are provided between one end of the first negative stop pawl 3212 close to the tooth portion and the first boss 3241 of the second sub-coil spring driving frame 324. When the first ratchet wheel 3211 is required to be stationary and not rotated, each return spring always remains in a compressed state, so as to provide a force for the corresponding stop pawl to approach the first ratchet wheel 3211; under normal circumstances, the first positive stop pawl 3213 and the first negative stop pawl 3212 will remain in a locked engagement state with the first ratchet wheel 3211, so that the first ratchet wheel 3211 and the second sub-coil spring driving frame 324 remain in a locked state, and the torque is transferred from the inner end of the first sub-coil spring 311 to the outer end of the second sub-coil spring 312, so that the two are connected in series. Similarly, the ratchet pawl mechanism in the second sub-coil spring locking member 323 includes a second ratchet 3231 fixedly sleeved on the ratchet shaft 325, and a second positive stop pawl 3233 and a second negative stop pawl 3232 matched with the second ratchet 3231 through the teeth, and the inner end of the second sub-coil spring 312 is fixedly connected to the second ratchet 3231; a second boss 1111 is provided on the lower surface of the top end of the upper shell 111, and the second positive stop pawl 3233 and the second negative stop pawl 3232 are engaged with the second ratchet 3231 through the teeth. A second positive return spring 3236 and a second positive stop switch 3237 are provided between one end of the second positive stop pawl 3233 close to the tooth portion and the second boss 1111 of the upper shell 111, and a second negative return spring 3234 and a second negative stop switch 3235 are provided between one end of the second negative stop pawl 3232 close to the tooth portion and the second boss 1111 of the upper shell 111.It should be noted that each stop switch adopts an electromagnetic switch, more specifically, an armature switch, which is controlled by the control unit 400. When the armature switch is turned on, it will provide a force for the corresponding stop pawl to move away from the ratchet in contact with the corresponding stop pawl, and the force is greater than the force provided by the reset spring, thereby separating the corresponding stop pawl from the ratchet; when the armature switch is disconnected, the force it provides to the corresponding stop pawl disappears, and the corresponding stop pawl contacts the ratchet under the action of the reset spring.

[0125] Further, see Fig.12 Figures (a), (b), and (c) are schematic diagrams of the working process of the stiffness adjustment component 320 of this embodiment. At this time, only the positional relationship between the second sub-coil spring 312 and its accessories on the same layer can be seen from the top view, and the stiffness adjustment is mainly achieved by controlling the second layer stop pawl by the second layer (i.e., upper layer) stop switch. At this time, the outer end of the first sub-coil spring 311 is subjected to a clockwise load torque, wherein:

[0126] When the load moment is just connected, the stiffness adjustment component 320 works as follows: Fig.12 In the mode shown in (a), the coil spring is compressed and deformed, the outer end of the first coil spring 311 is fixed to the first pin 3223 on the first coil spring drive frame 322, and is subjected to the clockwise torque generated by the load, the inner end of the first coil spring 311 is fixed to the first ratchet 3211, and the first positive stop pawl 3213 and the first negative stop pawl 3212 are in contact with the teeth of the first ratchet 3211, so that the inner end of the first coil spring 311 and the second coil spring drive frame 324 remain locked, and the torque is transmitted from the inner end of the first coil spring 311 to the outer end of the second coil spring 312, and is subjected to the clockwise torque generated by the load. Fig.12 As shown in (a), at this time, the second positive stop pawl 3233 on the right side is in contact with the teeth of the second ratchet 3231, and the second negative stop pawl 3232 on the left side is separated from the teeth of the second ratchet 3231. Under the stopping action of the second positive stop pawl 3233 on the right side, although the second ratchet 3231 is subjected to the clockwise torque generated by the inner end of the second sub-coil spring 312, it can remain stationary, thereby ensuring that the counterclockwise elastic torque jointly generated by the first sub-coil spring 311 and the second sub-coil spring 312 can balance the clockwise torque generated by the load. If the load reaches the desired working angle (position) at this time, the stiffness adjustment component 320 works as follows: Fig.12 In the mode shown in (c), at this time, the second positive stopping pawl 3233 and the second negative stopping pawl 3232 are both engaged with the second ratchet wheel 3231 to ensure that the second ratchet wheel 3231 is fixed.

[0127] When the load torque increases, the outer end of the first sub-coil spring 311 will continue to rotate clockwise, further compressing the coil spring until the torque balance is reached again.

[0128] When the load torque decreases, the outer end of the first sub-coil spring 311 rotates counterclockwise to relax the coil spring until the torque balance is reached again.

[0129] After the torque is balanced, if the load is required to rotate counterclockwise by a certain angle due to the working angle (position), that is, the outer end of the first sub-coil spring 311 is required to rotate counterclockwise by a certain angle, the stiffness adjustment component 320 works as follows: Fig.12 In the mode shown in (a), at this time, because the second negative stop pawl 3232 on the left is disengaged from the second ratchet 3231 and the second positive stop pawl 3233 on the right is engaged with the second ratchet 3231, the second ratchet 3231 can rotate counterclockwise under the drive of the adjusting handle (the adjusting handle is not shown in the figure), that is, the inner end of the second sub-coil spring 312 is rotated counterclockwise by a certain angle, thereby realizing that the load is rotated counterclockwise by a certain angle to reach the desired working angle (position).

[0130] Similarly, after the torque is balanced, if the load is required to rotate clockwise by a certain angle due to the working angle (position), that is, the outer end of the first sub-coil spring 311 is required to rotate clockwise by a certain angle, then the stiffness adjustment component 320 works as follows: Fig.12 In the mode shown in (b), at this time, because the second positive stop pawl 3233 on the right is disengaged from the second ratchet 3231 and the second negative stop pawl 3232 on the left is engaged with the second ratchet 3231, the second ratchet 3231 can rotate clockwise under the drive of the adjustment handle, that is, the inner end of the second sub-coil spring 312 is rotated clockwise by a certain angle, so that the load is rotated clockwise by a certain angle to reach the desired working angle (position). It should be noted that since the inner end of the second sub-coil spring 312 is subjected to the clockwise spring elastic force at this time, when the second ratchet 3231 rotates clockwise by a certain angle, the second positive stop switch 3237 on the right needs to be released immediately to allow the second positive stop pawl 3233 to engage with the second ratchet 3231, and at the same time the second negative stop pawl 3232 to engage with the second ratchet 3231, that is, return to the reverse direction. Figure 6 The working state shown in (a) realizes clockwise stopping.

[0131] Understandably, Fig.12 FIG. 3 shows a typical installation method of the nonlinear elastic element 310 (mainly including the first sub-coil spring 311 and the second sub-coil spring 312). If the two sub-coil springs can bear the load moment in the counterclockwise direction according to the design requirements, then Fig.12Based on the installation method shown in (a), the first sub-coil spring 311 and the second sub-coil spring 312 can be installed by flipping the first sub-coil spring 311 and the second sub-coil spring 312 in a mirror image. At this time, the second negative stop pawl 3232 provides a stop torque for the second ratchet wheel 3231. Therefore, the above mechanism can achieve load torque balance in both clockwise and counterclockwise directions. In actual application, a suitable installation method should be selected according to the direction of the load torque to install the nonlinear elastic element 310.

[0132] It should be noted that the adjustment handle in this embodiment can be replaced by a coil spring adjustment motor, and the adjustment of the inner end angular position of the first sub-coil spring 311 can be achieved through electronic control; the ratchet pawl mechanism in the coil spring locking member in this embodiment can be replaced by a friction cam mechanism or other similar intermittent motion mechanism.

[0133] It can be understood that in this embodiment, the load torque is transmitted to the corresponding sub-coil spring through the outer end of each sub-coil spring, that is, the inner end of the coil spring is fixed and the outer end is movable, which can increase the durability of the coil spring compared to the method of transmitting the load torque from the inner end. Since the curvature radius of the coil spring at the outer ring is larger, the deformation of the coil spring at the outer ring is smaller than that at the inner ring during operation, which will extend the service life of the coil spring.

[0134] Further, the control unit 400 is arranged in the upper shell 111 of the frame body 110 and is located below the first sub-coil spring drive frame 322, including a circuit board 410, a main controller, an angle sensor and a current sensor (the main controller, the current sensor and the angle sensor are not shown in the figure) arranged on the circuit board 410, the current sensor and the angle sensor are connected to the main controller, the current sensor can adopt an existing on-board current sensor, which is used to detect the current signal of the drive motor 220, and the angle sensor is used to collect the angle of the central shaft 210 in real time (the angle reflects the number of rotations and the speed of the central shaft), the circuit board is fixedly connected to the lower shell 112 by bolts, and the main controller is used to control the drive motor 220 and each stop switch according to the current signal of the drive motor 220 and the angle signal of the central shaft 210, so as to automatically adjust the stiffness of the nonlinear elastic element 310 according to different load sizes and maintain the mover frame A1 at the target position. A wire hole is opened on the side wall of the upper shell 111, and the cables on the circuit board are led out from the wire hole. Optionally, the control unit 400 further includes a dust cover 420 having a central through hole, the dust cover 420 is fixedly connected to the frame body 110, and the central through hole of the dust cover 420 is rotatably connected to the third shaft neck 3221 of the first sub-coil spring driving frame 322 via a sixth bearing f.

[0135] Furthermore, in order to achieve accurate tracking of the target position of the mover frame A1 at different step frequencies, the control unit 400 controls the stiffness adjustment component 320 and the drive motor 220 according to the current posture and target posture of the mover frame A1, and in combination with the current signal of the drive motor 220 and the angle signal of the central axis 210, so as to balance the load torque, the nonlinear elastic element torque and the drive torque while ensuring that the mover frame A1 can reach the target posture. The control unit 400 of this embodiment also includes an inertial measurement unit (IMU, which is not shown in the figure) arranged on the circuit board 410, which is used to collect the attitude angle and displacement of the mover frame A1 in real time and transmit it to the main controller in the control unit 400. The main controller controls the drive motor 220 by adding a posture loop of the mover frame A1 on the basis of the vector control (Field-Oriented Control, FOC) method. The FOC method adopts three-loop control, which are a current loop, a speed loop and a position loop from the inside to the outside. The added posture loop is used to obtain the expected rotation angle of the drive motor 220 according to the deviation between the current posture of the mover frame A1 and the target posture, and the expected rotation angle is input into the position loop in the FOC. After calculation by the FOC method, the expected current value of the drive motor to maintain or reach the expected rotation angle is obtained, thereby realizing accurate tracking of the target posture of the mover frame A1.

[0136] Optionally, the carrying system provided in the embodiment of the present disclosure further includes a handle E matched with the gear C2 and a power module F electrically connected to the drive motor 220, so that the carrying system of this embodiment has a manual power generation function. When manual power generation is required, firstly, the mover frame A1 and the stator frame A2 are unlocked by the locking mechanism A5, and then the mover frame A1 together with the adaptive drive module D and the package B are slid out from the upper end of the stator frame A1 to be separated from the stator frame A2, and then the main controller is triggered by the button connected to the main controller in the control unit 400 to control each stop switch to separate all the stop pawls (3212, 3213, 3232, 3233) from the teeth of the corresponding ratchet wheels (3211, 3231). At this time, the inner ends of the first sub-coil spring 311 and the second sub-coil spring 312 are both in a free state, and then the handle E is connected to the gear C2. By rotating the handle E, the power is transmitted to the rotor frame 221 in the drive motor 220 through the gear C2, the external terminal 120, the reducer 230, and the central shaft 210 in turn. The magnet 222 on the rotor frame 221 and the coil 224 move relative to each other, cutting the magnetic flux lines to generate current, thereby achieving the manual power generation effect. The current generated by the driving motor 220 is led out to a power module (the power module adopts a currently available power module) F through electric wires, and the power module F supplies power to the outside.

[0137] 2. Parallel drive module II

[0138] See also Fig.13, Fig.14 (It should be noted that Fig.13 , Fig.14 The up and down directions shown correspond to Figure 1 The rear and front of the parallel drive module II includes a frame 100, a drive unit 200, a parallel variable stiffness unit 300' and a control unit 400 arranged in the frame 100; wherein,

[0139] The frame 100 includes a frame body 110 and an external connection terminal 120 disposed on the frame body 110. The frame body 110 is fixedly connected to a side of the mover frame A1 facing away from the stator frame A2 by bolts. The load transmitted by the transmission unit D (the load mainly includes the weight of the package B and its internal weight, and the sum of the weight of the mover frame A1 and the components installed on the mover frame A1) is connected through the external connection terminal 120, and the power provided by the drive unit 200 is transmitted to the mover frame A1 and the package B;

[0140] The driving unit 200 includes a central shaft 210 and a driving motor 220 which are coaxially arranged, and the driving motor 220 drives the central shaft 210 to rotate, and then is connected to the external connection end 120 through a reducer 230;

[0141] The parallel variable stiffness unit 300' comprises a nonlinear elastic element 310' and a stiffness adjustment component 320'. The nonlinear elastic element 310' is composed of a first sub-coil spring 311' and a second sub-coil spring 312' which are connected in parallel through the stiffness adjustment component 320' and have the same number of working turns. The stiffness adjustment component 320' is also connected to the central shaft 210. The load torque is transmitted to the stiffness adjustment component 320' via the reducer 230 and the central shaft 210, and then the torque is applied to the inner end of each sub-coil spring. The stiffness adjustment component 320' changes the number of working turns and output torque of each sub-coil spring by unidirectional or bidirectional locking of the outer end of each sub-coil spring, thereby balancing the corresponding load torque. The stiffness adjustment component 320' pre-tightens or unloads the outer end of each sub-coil spring to adjust the initial angle of the inner end of each sub-coil spring, and the initial angle corresponds to the initial position of the mover frame A1 relative to the stator frame A2.

[0142] The control unit 400 is used to control the stiffness adjustment component 320' and the drive motor 220 according to the current signal of the drive motor 220 and the rotation angle signal of the central shaft 210, so as to achieve a balance among the load torque, the torque of the nonlinear elastic element 310' and the output torque of the drive motor 220 (hereinafter the output torque of the drive motor is referred to as "drive torque"), thereby providing power to the mover frame A1 to maintain the target position and realizing adaptive adjustment of different load sizes.

[0143] The main difference between the parallel drive module II and the series drive module I is that the variable stiffness unit in the parallel drive module II is a parallel variable stiffness unit 300', in which the nonlinear elastic element 310' is composed of two sub-coil springs connected in parallel, and the structure of the stiffness adjustment component 320' is adaptively adjusted, and a partition is added in the upper shell of the frame body, but the parallel variable stiffness unit 300' and the control unit 400 are still located in the upper shell, and the drive unit is still located in the lower shell. The drive unit in the parallel drive module II is exactly the same as the drive unit in the series drive module I, and will not be repeated here. The specific implementation method and working process of the parallel variable stiffness unit 300' will be described in detail below.

[0144] See also Fig.15 , Fig.16 In the parallel variable stiffness unit 300' of this embodiment, the nonlinear elastic element 310' is composed of two sub-coil springs connected in parallel. The two sub-coil springs have the same number of working turns, that is, they have the same angular range during rotation. Each sub-coil spring is arranged in layers in the upper shell 111 of the frame body 110, and the first sub-coil spring 311' is arranged closer to the central axis 210 than the second sub-coil spring 312'. Each sub-coil spring is a linear coil spring, or a nonlinear coil spring, or one of them is a linear coil spring and the other is a nonlinear coil spring; the nonlinear coil spring is a planar spiral spring formed by connecting multiple coil spring segments end to end and forming an integral body, and the stiffness of two adjacent coil spring segments is different. The nonlinear elastic element 310' is designed according to the following steps:

[0145] Step 1: Segment the working curve of the given parallel drive module. The working curve of the parallel drive module is a functional relationship between the rotation angle (independent variable) of the central axis 210 and the torque (dependent variable) output through the external terminal 120. The number of segments S is determined according to the position control accuracy and stiffness adjustment accuracy requirements of the mover frame A1. The higher the accuracy requirement, the larger the number of segments S, and S is a positive integer greater than or equal to 2.

[0146] Step 2: Assume that the number of coiled spring segments contained in the first sub-coil spring 311' is P, and the number of coiled spring segments contained in the second sub-coil spring 312' is Q, and both P and Q are positive integers greater than or equal to 1, and satisfy S≥P, S≥Q. When the number of coiled spring segments of the sub-coil spring is 1, the sub-coil spring is a linear coiled spring, and when the number of coiled spring segments of the sub-coil spring is greater than 1, the sub-coil spring is a nonlinear coiled spring;

[0147] Step 3, for the i-th section of the working curve, i=1, 2, ..., S, the torque at a certain angle φ on the section of the working curve is taken as the sum of the torque of the first sub-spring 311' and the torque of the second sub-spring 312' at the angle φ, and the slope of the working curve at the angle φ is taken as the sum of the stiffness of the first sub-spring 311' and the stiffness of the second sub-spring 312' at the angle φ, thereby obtaining the respective working curves of the first sub-spring 311' and the second sub-spring 312' within the angle range corresponding to the i-th section of the working curve;

[0148] Step 4: According to the working curves of the first sub-coil spring 311' and the second sub-coil spring 312', the P coil spring segments of the first sub-coil spring 311' and the Q coil spring segments of the second sub-coil spring 312' are designed respectively according to the industry standard JB / T7366-1994 to obtain the parameters of each coil spring segment, including elastic modulus E, cross-sectional thickness h, cross-sectional width b and unfolded length l;

[0149] Step 5: The overall dimensions of each sub-coil spring in the free state obtained according to the above design steps should meet the set space requirements. If not, return to step 2 and adjust the parameters P and Q to redesign.

[0150] It can be understood that since the rotation angle of the external terminal 120 connected to the load (that is, the displacement of the mover frame A1) is proportional to the rotation angle of the central axis 210 (the power transfer ratio of the reducer), and the initial rotation angle of the inner ring of the coil spring can be adjusted (the specific adjustment process will be given below), in most applications, when the load rotation angle range and the working torque relationship are required to meet the set function curve, even in a limited installation space, a nonlinear coil spring that approximately meets the set function curve can still be designed according to the above steps.

[0151] In this embodiment, two linear coil springs with different stiffness are provided, and the sub-coil spring with greater stiffness is used as the first sub-coil spring 311', and the sub-coil spring with less stiffness is used as the second sub-coil spring 312' and is arranged above the first sub-coil spring 311'. The stiffness of the nonlinear coil spring 310' is obtained by connecting the first sub-coil spring 311' and the second sub-coil spring 312' in parallel, and the first sub-coil spring 311' and the second sub-coil spring 312' with different stiffness can be selected and combined according to actual needs.

[0152] In the parallel variable stiffness unit 300' of this embodiment, a stiffness adjustment mechanism is respectively configured for each sub-coil spring, and the two stiffness adjustment mechanisms together constitute the stiffness adjustment assembly 320' in the parallel variable stiffness unit 300', and are both coaxial with the central axis 210. Each stiffness adjustment mechanism is controlled by the control unit 400 to adjust the stiffness of the coil spring. Specifically, each stiffness adjustment mechanism locks or unloads the corresponding sub-coil spring until the total elastic moment generated by the nonlinear elastic element 310' reaches the load moment and then maintains balance. The first stiffness adjustment mechanism includes a first sub-coil spring locking piece 321' and a first sub-coil spring fixing frame 322', and the second stiffness adjustment mechanism includes a second sub-coil spring locking piece 323' and a second sub-coil spring fixing frame 324'. A partition 111a is also provided in the upper shell 111 to separate the upper shell 111 into an upper space and a lower space. The first stiffness adjustment mechanism and the first sub-coil spring 311 are located in the lower space of the upper shell 111, and the second stiffness adjustment mechanism and the second sub-coil spring 312' are located in the upper space of the upper shell 111. The partition 111a is a circular plate with a center hole, and a first boss 1112 for installing the first sub-coil spring locking piece 321' is provided on the lower end surface of the partition 111a. The outer end of the partition 111a is fixedly connected to the upper shell 111 by screws, and a second boss 1111 for installing the second sub-coil spring locking piece 323' is provided on the lower end surface of the top cover of the upper shell 111.

[0153] The first sub-coil spring locking member 321' and the second sub-coil spring locking member 323' respectively include a ratchet pawl mechanism and a matching stop switch and a reset spring. The ratchet pawl mechanisms in the first sub-coil spring locking member 321' and the second sub-coil spring locking member 323' share a ratchet shaft 325'. The ratchet shaft 325' adopts a stepped shaft. The top end of the ratchet shaft 325' is rotatably connected to the frame body 110 through a fifth bearing e arranged at the center hole of the upper shell 111. The bottom end of the ratchet shaft 325' is fixedly connected to the top end of the central shaft 210 through a set screw 3218'. The angle difference between the inner end angular position and the outer end angular position of the sub-coil spring is the number of turns compressed by the sub-coil spring. Different numbers of compressed turns will generate different elastic moments. The above-mentioned nonlinear coil spring design method can be used for design and manufacturing. The nonlinear coil spring has the characteristic of adaptive load torque. In this embodiment, when the load is connected, the coil spring segments are compressed in order from small to large stiffness according to the stiffness characteristics of each coil spring segment, that is, the coil spring segment with the smallest stiffness is compressed first. If the load torque is greater than the current coil spring torque, the coil spring segment with larger stiffness is compressed until balance is achieved.

[0154] The first sub-coil spring locking member 321' comprises a first ratchet 3211' rotatably mounted on the ratchet shaft 325' via a first bearing bush 3219', a first positive stop pawl 3212' and a first negative stop pawl 3213' matched with the first ratchet 3211' via a tooth portion, a first positive return spring 3214' and a first positive stop switch 3215' arranged between an end of the first positive stop pawl 3212' close to the tooth portion and the first boss 1112 of the partition 111a, and a first negative return spring 3216' and a first negative stop switch 3217' arranged between an end of the first negative stop pawl 3213' close to the tooth portion and the first boss 1112 of the partition 111a. The switch 3217', the first positive stop pawl 3212' and the first negative stop pawl 3213' are rotatably connected to the first boss 1112 of the partition 111a at one end away from their respective teeth, and a first sub-spring fixing frame 322' integrally formed with the first ratchet 3211' is provided on the outer periphery of the first ratchet 3211', and a first pin 3221' for fixing the outer end of the first sub-spring 311 is provided on the lower end surface of the first sub-spring fixing frame 322', and the inner end of the first sub-spring 311' is fixedly connected to the ratchet shaft 325', and an eighth bearing h is provided at the center hole of the partition 111a, and the partition 111a is rotatably mounted on the ratchet shaft 325' through the seventh bearing g. The second sub-coil spring locking member 323' comprises a second ratchet 3231' rotatably mounted on the ratchet shaft 325' via a second bearing bush 3239', a second positive stop pawl 3232' and a second negative stop pawl 3233' matched with the second ratchet 3231' via a tooth portion, a second positive return spring 3234' and a second positive stop switch 3235' arranged between an end of the second positive stop pawl 3232' close to the tooth portion and a second boss 1111 on the lower end surface of the top cover of the upper shell 111, and a second negative stop switch 3235' arranged between an end of the second negative stop pawl 3233' close to the tooth portion and a second boss 1111 on the lower end surface of the top cover of the upper shell 111. The second negative return spring 3236 and the second negative stop switch 3237' between the boss 1111, the second positive stop pawl 3232' and the second negative stop pawl 3233' are rotatably connected to the second boss 1111 on the lower end surface of the top cover of the upper shell 111, and a second sub-coil spring fixing frame 324' integrally formed with the second ratchet 3231' is provided on the outer periphery of the second ratchet 3231', and a second pin 3241' for fixing the outer end of the second sub-coil spring 312' is provided on the lower end surface of the second sub-coil spring fixing frame 324', and the inner end of the second sub-coil spring 312' is fixedly connected to the ratchet shaft 325'.Each return spring is always kept in a compressed state, so as to provide each stop pawl with a force to approach the corresponding ratchet wheel. The first sub-coil spring locking member 321' is used as an example for explanation: during the stiffness adjustment process, by switching the states of the two stop switches, only one of the first positive stop pawl 3212' and the first negative stop pawl 3213' contacts the tooth portion of the first ratchet wheel 3211', and then the first ratchet wheel 3211' can only rotate in a single direction, so that the first sub-coil spring 311' is in a pre-tightened or unloaded state (in this embodiment, it is stipulated that when the first ratchet wheel 3211' and the second ratchet wheel 3231' rotate counterclockwise, the sub-coil spring is in a pre-tightened compressed state, and the elastic torque increases; When the first ratchet 3211' and the second ratchet 3231' rotate clockwise, the sub-coil spring is in an unloaded state and the elastic torque is reduced), and when the first ratchet 3211' rotates in the opposite direction, the tooth portion of the first ratchet 3211' will be resisted by the stop pawl currently in contact with the first ratchet 3211', so that the first ratchet 3211' is in a stopped state, so that the first ratchet 3211' can only rotate in a single direction, and when the torque reaches equilibrium, the first positive stop pawl 3212' and the first negative stop pawl 3213' both contact the tooth portion of the first ratchet 3211', so that the outer end of the first sub-coil spring 311' is locked, thereby keeping the current elastic torque unchanged. It should be noted that each stop switch adopts an electromagnetic switch, more specifically, an armature switch, which is controlled by the control unit 400. When the armature switch is turned on, it will provide a force for the corresponding stop pawl to move away from the ratchet in contact with the corresponding stop pawl, and the force is greater than the force provided by the reset spring, thereby separating the corresponding stop pawl from the ratchet; when the armature switch is disconnected, the force it provides to the corresponding stop pawl disappears, and the corresponding stop pawl contacts the ratchet under the action of the reset spring.

[0155] The characteristics of the parallel coil spring in this embodiment are: the two sub-coil springs participate in the stiffness adjustment synchronously, the total elastic torque of the parallel coil spring is determined by the elastic torque of the two sub-coil springs, when the load increases, the stiffness adjustment components of the two sub-coil springs will simultaneously adjust the elastic torque of the corresponding sub-coil springs, so that the total elastic torque of the nonlinear elastic element 310' increases, and when the load decreases, the stiffness adjustment components of the two sub-coil springs will simultaneously adjust the total elastic torque of the corresponding sub-coil springs, so that the total elastic torque of the nonlinear elastic element 310' decreases.

[0156] Furthermore, combined with Fig.17 Figures (a), (b), and (c) are schematic diagrams of the working process of the stiffness adjustment component 320' of this embodiment. The two sub-coil springs are synchronously involved in the stiffness adjustment. At this time, the inner ends of the first sub-coil spring 311' and the second sub-coil spring 312' are subjected to a counterclockwise load moment, wherein:

[0157] When the load moment is just connected, the stiffness adjustment component 320' works as follows Fig.17 In the mode shown in (a), the coil spring is compressed and deformed, and the outer end of the first sub-coil spring 311' is fixed to the first pin 3221' on the first sub-coil spring fixing frame 322' (the first sub-coil spring fixing frame 322' and the first ratchet 3211' are integrally formed), that is, the outer end of the first sub-coil spring 311' keeps synchronous movement with the first ratchet 3211', and the inner end of the first sub-coil spring 311' is fixed to the ratchet shaft 325' and is subjected to the counterclockwise torque generated by the load, the first positive stop pawl 3212' on the right side is separated from the teeth of the first ratchet 3211', and the first negative stop pawl 3213' on the left side contacts the teeth of the first ratchet 3211', so that the outer end of the first sub-coil spring 311' At the same time, the outer end of the second sub-coil spring 312' is fixed to the second pin 3241' on the second sub-coil spring fixing frame 324' (the second sub-coil spring fixing frame 324' is integrally formed with the second ratchet 3231'), and the inner end of the second sub-coil spring 312' is fixed to the ratchet shaft 325' and is subjected to the counterclockwise torque generated by the load, the second positive stop pawl 3232' on the right side is separated from the teeth of the second ratchet 3231', and the second negative stop pawl 3233' on the left side is in contact with the teeth of the second ratchet 3231', so that the outer end of the second sub-coil spring 312' is subjected to the counterclockwise torque generated by the load and remains locked. Thus, the outer ends of the first sub-coil spring 311' and the second sub-coil spring 312' are both locked, and the clockwise and reverse elastic torques generated by the two can balance the counterclockwise torque generated by the load. If the load reaches the desired working angle (position) at this time, the stiffness adjustment component 320' works as follows: Fig.17 In the mode shown in (c), at this time, the first positive stop pawl 3212' and the first negative stop pawl 3213' are both engaged with the first ratchet 3211' to ensure that the first ratchet 3211' is fixed, and the second positive stop pawl 3232' and the second negative stop pawl 3233' are both engaged with the second ratchet 3231' to ensure that the second ratchet 3231' is fixed.

[0158] When the load moment increases, the inner ends of the first sub-coil spring 311 ′ and the second sub-coil spring 312 ′ will continue to rotate counterclockwise, further compressing the coil springs until the moment balance is reached again.

[0159] When the load torque decreases, the inner ends of the first sub-coil spring 311 ′ and the second sub-coil spring 312 ′ will rotate clockwise to relax the coil springs until the torque balance is achieved again.

[0160] After the torque is balanced, if the load is required to rotate counterclockwise by a certain angle due to the working angle (position), that is, the inner ends of the two coil springs are required to rotate counterclockwise by a certain angle, the stiffness adjustment component 320 is as follows: Fig.17 The machine works in the mode shown in (b) for a short period of time. During this time, the first negative stop pawl 3213 and the second negative stop pawl 3233' on the left are disengaged from the first ratchet 3211' and the second ratchet 3231' respectively. The two ratchet wheels are driven by the elastic torque of the coil spring to rotate counterclockwise by a certain angle, thereby realizing that the outer end of the sub-coil spring rotates counterclockwise by a corresponding angle. Since the torque is balanced, the inner end of each sub-coil spring will rotate by the same angle as the counterclockwise rotation of the outer end of the sub-coil spring, so that the load reaches the desired working angle. Then, the first negative stop pawl 3213' and the second negative stop pawl 3233' are controlled to quickly and bidirectionally lock the first ratchet 3211' and the second ratchet 3231' to prevent the outer end of the coil spring from rotating counterclockwise beyond the desired angle (position); if the rotation angle is less than the desired working angle, the stiffness adjustment component 320' continues to be moved as shown in FIG. Fig.17 Repeat the operation in the mode shown in (b) to achieve the outer end of the coil spring rotating counterclockwise by a certain angle to reach the desired working angle (position), and achieve the balance between the load torque and the coil spring torque again.

[0161] Similarly, after the torque is balanced, if the load is required to rotate clockwise by a certain angle due to the working angle (position), that is, the inner ends of the two coil springs are required to rotate clockwise by a certain angle, then the stiffness adjustment component 320' works as follows: Fig.17 In the mode shown in (a), at this time, the drive motor 220 drives the load to rotate clockwise to unload the coil spring. When the elastic torque of the coil spring is zero, the drive motor 220 continues to drive the coil spring to rotate a certain angle clockwise, thereby pushing the outer end of the coil spring to rotate clockwise by a corresponding angle. At this time, the first negative stop pawl 3213' and the second negative stop pawl 3233' will not prevent the first ratchet 3211' and the second ratchet 3231' from rotating clockwise. When the outer end of the coil spring reaches the desired angle (position), the first positive stop pawl 3212' and the second positive stop pawl 3232' are controlled to lock the first ratchet 3211' and the second ratchet 3231' to ensure that the outer end of the coil spring is locked at the desired angle (position). Then, continue to make the stiffness adjustment component 320' as shown in Fig.17 Repeat the operation in the mode shown in (a) to connect the load torque, the inner end of the coil spring rotates counterclockwise, the coil spring is compressed and deformed, so that the outer end of the coil spring rotates clockwise by a certain angle to reach the desired working angle (position), and the load torque and the coil spring torque are balanced again. Finally, the stop pawl is used to lock each ratchet in a bidirectional manner.

[0162] Understandably, Fig.17FIG. 1 shows a typical installation method of the nonlinear elastic element 310' (mainly including the first sub-coil spring 311' and the second sub-coil spring 312'). If the two sub-coil springs can bear the load moment in the clockwise direction according to the design requirements, then Fig.17 Based on the installation method shown in (a), the first sub-coil spring 311' and the second sub-coil spring 312' can be installed by flipping the left and right mirror images at the same time. At this time, the positive stop pawl provides the stop torque for each ratchet. Therefore, the above mechanism can achieve load torque balance in both clockwise and counterclockwise directions. In actual application, the appropriate installation method should be selected according to the direction of the load torque to install the nonlinear elastic element 310'.

[0163] It should be noted that the ratchet and pawl mechanism in the coil spring locking member of the present embodiment can be replaced by a friction cam mechanism or other similar intermittent motion mechanism.

[0164] The manual power generation process of the parallel drive module is the same as that of the series drive module. The closed-loop control process of the control unit 400 of the parallel drive module over the drive motor 220 is the same as the closed-loop control process of the control unit 400 of the series drive module over the drive motor 220. It can also realize adaptive adjustment of different synchronous frequency sizes, which will not be repeated here.

[0165] 3. Single coil spring drive module III

[0166] See also Fig.18 (It should be noted that Fig.18 The up and down directions shown correspond to Figure 1 The single coil spring drive module III includes a frame 100, a drive unit 200, a variable stiffness unit 300* and a control unit 400 arranged in the frame 100; wherein,

[0167] The frame 100 includes a frame body 110 and an external connection terminal 120 disposed on the frame body 110. The frame body 110 is fixedly connected to a side of the mover frame A1 facing away from the stator frame A2 by bolts. The load transmitted by the transmission unit D (the load mainly includes the weight of the package B and its internal weight, and the sum of the weight of the mover frame A1 and the components installed on the mover frame A1) is connected through the external connection terminal 120, and the power provided by the drive unit 200 is transmitted to the mover frame A1 and the package B;

[0168] The driving unit 200 includes a central shaft 210 and a driving motor 220 which are coaxially arranged, and the driving motor 220 drives the central shaft 210 to rotate, and then is connected to the external connection end 120 through a reducer 230;

[0169] The variable stiffness unit 300* includes a nonlinear coil spring 310* and a stiffness adjustment component 320*. The nonlinear coil spring 310* is a planar spiral spring formed by connecting multiple coil springs in sequence end to end and integrally formed. The stiffness of two adjacent coil spring sections is different. The stiffness adjustment component 320* is connected between the central shaft 210* and the nonlinear coil spring 310*. The load torque is transmitted to the stiffness adjustment component 320* via the reducer 230 and the central shaft 210, and then the torque is applied to one end (such as the outer end) of the nonlinear coil spring 310*. The stiffness adjustment component 320* changes the number of working turns and output torque of the nonlinear coil spring 310* by unidirectional or bidirectional locking of one end of the nonlinear coil spring 310*, thereby balancing the corresponding load torque. The stiffness adjustment component 320* pre-tightens or unloads the other end (such as the inner end) of the nonlinear coil spring 310*, so that the mover frame A1 reaches the desired working position.

[0170] The control unit 400 is used to control the stiffness adjustment component 320* and the drive motor 220 according to the current signal of the drive motor 220 and the rotation angle signal of the central shaft 210, so as to achieve a balance among the load torque, the torque of the nonlinear coil spring 310* and the output torque of the drive motor 220 (hereinafter the output torque of the drive motor is referred to as "drive torque"), thereby realizing adaptive adjustment of different load sizes while providing power for the carrier.

[0171] The main difference between the single coil spring drive module III and the series drive module I is that the elastic element in the variable stiffness unit 300* of the single coil spring drive module III contains only one single plane scroll spring composed of multiple coil spring segments (each coil spring segment is a corresponding rectangular steel strip) connected end to end and integrally formed. The design process of the plane scroll spring refers to the design process of the nonlinear coil spring in the series drive module I, and the first coil spring segment is located at the outermost end of the nonlinear coil spring 310*; correspondingly, the number of stiffness adjustment mechanisms in the stiffness adjustment component 320* is also reduced to one. The specific implementation of the drive unit and control unit in the single coil spring drive module III refers to the drive unit and control unit in the series drive module I, which will not be repeated here. The specific implementation of the variable stiffness unit 300* will be described in detail below.

[0172] See also Fig.19 , Fig. 20The stiffness adjustment component 320* includes a coil spring locking member 321*, a coil spring driving frame 322*, and a coil spring adjustment motor 323. The coil spring adjustment motor 323* is arranged at the center of the top cover of the upper shell 111 of the frame body 110, and the output end of the coil spring adjustment motor 323* is connected to the inner end of the nonlinear coil spring 310*. The coil spring adjustment motor 323 is controlled by the control unit 400 to adjust the inner end angular position of the nonlinear coil spring 310*. The angle difference between the inner end angular position and the outer end angular position of the coil spring is the number of coils compressed by the nonlinear coil spring 310*. Different numbers of compressed coils generate different elastic moments, and the nonlinear coil spring design method can be used for design and manufacturing. The nonlinear coil spring 310* has the characteristic of adaptive load torque. In this embodiment, when the load is connected, the coil spring segments are compressed in order from small to large stiffness according to the stiffness characteristics of each coil spring segment, that is, the coil spring segment with the smallest stiffness is compressed first. If the load torque is greater than the current coil spring torque, the coil spring segment with larger stiffness is compressed until balance is achieved.

[0173] In the stiffness adjustment component 320* of the variable stiffness unit 300*, the coil spring driving frame 322* is a circular plate with a third shaft neck 3221* at the center of the lower end surface, and the circular plate and the third shaft neck 3221* are both provided with a center hole matching the central axis 210. The third shaft neck 3221* at the center of the coil spring driving frame 322* is fixedly sleeved on the top end of the central axis 210 by a second set screw 3222*, so as to rotate synchronously with the central axis 210. The nonlinear coil spring 310* is placed on the upper end surface of the coil spring driving frame 322*, and the upper end surface of the coil spring driving frame 322* is provided with a second column pin 3223* for fixing the outer end of the nonlinear coil spring 310*. The load torque is transmitted from the outer end of the nonlinear coil spring 310* into the nonlinear coil spring 310*, and a gap is left between the outer edge of the coil spring driving frame 322* and the inner side wall of the upper shell 111. The coil spring locking member 321* includes a ratchet pawl mechanism and a matching stop switch and a reset spring; the ratchet pawl mechanism includes a ratchet 3210* coaxially arranged with the central axis 210, and a positive stop pawl 3213* and a negative stop pawl 3214* that cooperate with the ratchet 3210* through teeth. The center hole of the ratchet 3210* is fixed to the output shaft of the coil spring adjustment motor 323* by a first set screw 3212*, so as to rotate synchronously with the output shaft of the coil spring adjustment motor 323*. The first pin 3211* protruding from the ratchet 3210* can be inserted into the inner end ring of the nonlinear coil spring 310* to achieve a fixed connection, and there is relative rotation between the ratchet 3210* and the coil spring driving frame 322*, that is, the inner end and the outer end of the nonlinear coil spring 310* are driven to rotate relative to each other, thereby achieving compression or release of the nonlinear coil spring 310*; one end of the positive stop pawl 3213* and the negative stop pawl 3214* are both rotatably connected to the boss 111 on the lower surface of the top end of the upper shell 111. 1, a positive return spring 3215* and a positive stop switch 3216* are provided between one end of the positive stop pawl 3213* close to the tooth portion and the boss 1111, and a negative return spring 3217* and a negative stop switch 3218* are provided between one end of the negative stop pawl 3214* close to the tooth portion and the boss 1111. When the ratchet 3210* needs to be stationary and not rotated, the two return springs are always kept in a compressed state, so as to provide a thrust for the corresponding stop pawl to approach the ratchet 3210*. It should be noted that each stop switch adopts an electromagnetic switch, more specifically, an armature switch, which is controlled by the control unit 400. When the armature switch is turned on, it will provide a force for the corresponding stop pawl to move away from the ratchet in contact with the corresponding stop pawl, and the force is greater than the force provided by the reset spring, thereby separating the corresponding stop pawl from the ratchet; when the armature switch is disconnected, the force it provides to the corresponding stop pawl disappears, and the corresponding stop pawl contacts the ratchet under the action of the reset spring.

[0174] The coil spring adjustment motor 323* in this embodiment can be replaced by an adjustment handle, and the inner end angular position of the nonlinear coil spring 310* can be adjusted by manually rotating the adjustment handle; the ratchet pawl mechanism in the coil spring locking member in this embodiment can be replaced by a friction cam mechanism or other similar intermittent motion mechanism.

[0175] The working process of the adaptive stiffness adjustment of the single coil spring drive module III of this embodiment refers to the series drive module I, which will not be repeated here.

[0176] The backpack system provided in the embodiment of the present disclosure has three modes: suspension mode (i.e., working mode), locking mode, and manual power generation mode, which are described as follows:

[0177] 1. Suspension mode:

[0178] In the suspension mode, the locking mechanism A5 is in an unlocked state, that is, after the lock plug A51 is pulled out from the first slot A53 of the lock hook A55, the lock hook A55 is pulled out from the second slot A54 on the mover frame A1. At this time, there is only contact between the mover frame A1 and the stator frame A2, between the gear C2, the auxiliary gear C3 and the rack C1, and between the guide wheel group A32 and the vertical guide rail A31b and the horizontal guide rail A31a.

[0179] The load of the package B acts on the mover frame A1. At this time, under the action of gravity, the vertical guide rail A31b and the horizontal guide rail A31a on the mover frame A1 respectively roll with the vertical guide wheel A32b and the horizontal guide wheel A32a. The vertical guide rail A31b constrains the movement of the mover frame A1 in the sagittal plane normal direction (left and right direction of the body), and the horizontal guide rail A31a constrains the movement of the mover frame A1 in the coronal plane normal direction (front and back direction of the body). The mover frame A1 can only move along the cross-sectional normal direction (up and down direction of the body). When the mover frame A1 moves to the lowest part relative to the stator frame A2, the top surface of the second limit block A42 contacts the bottom surface of the first limit block A41 on the mover frame A2, so that the mover frame A1 will not separate from the stator frame A2.

[0180] When the mover frame A1 and the stator frame A2 move relative to each other, the movement is transmitted to the gear C2 through the rack C1. Since the gear C2 is fixedly connected to the external end 120 of the adaptive drive module D, the load is transmitted to the external end 120 in the form of load torque, and then transmitted to the center 210 through the reducer 230 (when the reducer 230 is not provided, it is transmitted to the center 210 through the drive motor 220). Since one end of the coil spring moves synchronously with the central axis 210, and the other end of the coil spring is connected to the ratchet pawl mechanism, the load torque is transmitted to the ratchet pawl mechanism through the coil spring, and then transmitted to the frame body 110 through the ratchet pawl mechanism. At this time, the central axis angle sensor in the adaptive drive module D detects the rotation angle of the central axis 210. Since there is a mechanical transmission ratio relationship between the rotation of the central axis 210 and the linear motion of the rack C1, the rotation angle of the central axis 210 corresponds to the displacement of the guide wheel group of the mover frame A1 on the L-shaped guide rail. The main controller in the control unit operates the drive module according to the rotation angle of the central axis 210, and rotates the corresponding number of circles to cause the mover frame A1 to generate a driving displacement relative to the stator frame A2, and finally makes the vertical displacement of the mover frame A1 relative to the ground zero, thereby achieving a load-reducing effect.

[0181] The adaptive adjustment process of the carrying system for load size or step frequency has been described in detail above in the working process of the drive module, and will not be repeated here.

[0182] 2. Lock mode:

[0183] In the locking mode, the locking mechanism A5 is in a locked state, that is, the lock hook A55 is inserted into the second slot A54 on the mover frame A1, and then the lock plug A51 is inserted into the first slot A53 of the lock hook A55. At this time, the mover frame A1 and the stator frame A2 cannot be relatively displaced, and the mover frame A1 and the stator frame A2 are locked. At this time, the carrying system is an ordinary backpack.

[0184] 3. Manual power generation mode:

[0185] The control unit controls all electromagnetic switches to disengage the pawl from the ratchet, inserts the square boss of the handle E into the square hole of the gear C2, and turns the handle E. Since all the pawls are disengaged from the ratchet, the rotational torque generated by the human body will not be transmitted to the frame in the end, but the winding frame 223 and the rotor frame 221 in the drive motor 220 will rotate relative to each other, and the coil 224 on the winding frame 223 and the magnet 222 on the rotor frame 221 will be relatively displaced to generate an induced current, which is then led out to the power module F to realize external power supply.

[0186] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0187] Although embodiments of the present disclosure have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and alterations may be made to the embodiments without departing from the principles and spirit of the present disclosure, the scope of which is defined by the claims and their equivalents.

Claims

1. An adaptive suspension load-reducing carrying system, characterized in that: It includes a back frame unit, a bag body, a transmission unit and an adaptive drive module; The back frame unit comprises a mover frame, a stator frame and a guide module, wherein the guide module is connected between the mover frame and the stator frame and is used to limit the mover frame to only reciprocate along the normal direction of the cross section of the carrying system relative to the stator frame, and a shoulder belt is provided on the side of the stator frame facing away from the mover frame; The enclosure is fixedly connected to a side of the mover frame facing away from the stator frame; The transmission unit is arranged between the mover frame and the stator frame, and includes a rack and a gear meshed by a toothed portion, wherein the rack is arranged along the normal direction of the cross section of the carrying system and is fixedly connected to the stator frame; The adaptive driving module comprises a frame, and a driving unit, a variable stiffness unit and a control unit arranged in the frame; The frame includes a frame body fixedly connected to a side of the mover frame facing away from the stator frame and an external connection end provided on the frame body, wherein the external connection end passes through a first hole on the mover frame and is fixedly connected to the gear, a load transmitted by the transmission unit is connected through the external connection end, and power provided by the drive unit is transmitted to the mover frame and the package body; The driving unit comprises a coaxially arranged central shaft and a driving motor, and the power output by the driving motor is transmitted to the external end through the central shaft; The variable stiffness unit comprises an elastic element and a stiffness adjustment component, wherein the stiffness adjustment component is connected to the elastic element and the central axis of the drive unit, the load torque is transmitted to the stiffness adjustment component through the central axis, and then the torque is applied to one end of the elastic element, the stiffness adjustment component changes the working number of turns and the output torque of the elastic element by unidirectional or bidirectional locking of one end of the elastic element, thereby balancing the corresponding load torque, and the stiffness adjustment component adjusts the initial angle of the elastic element by pre-tightening or unloading the other end of the elastic element, and the initial angle of the elastic element corresponds to the initial position of the mover frame relative to the stator frame; The control unit is used to control the stiffness adjustment component and the drive motor according to the current signal of the drive motor and the rotation angle signal of the central shaft, so as to achieve a balance among the load torque, the elastic element torque and the output torque of the drive motor, and realize adaptive adjustment of different load sizes while providing power to the mover frame and the package to maintain the target position.

2. The carrying system according to claim 1, characterized in that: The guide module includes two L-shaped guide rails fixedly arranged on the left and right sides of the mover frame respectively and a plurality of guide wheel groups installed on the side of the stator frame facing the mover frame, the horizontal section and the vertical section of each L-shaped guide rail are respectively used as the horizontal guide rail and the vertical guide rail; a plurality of guide wheel groups are evenly distributed on the left and right sides of the stator frame, each guide wheel group is respectively composed of two horizontal guide wheels and one vertical guide wheel, the two horizontal guide wheels are arranged at the front and rear sides of the horizontal guide rail and are rotatably sleeved on a corresponding horizontal guide wheel shaft fixedly connected to the stator frame, the vertical guide wheel is located on the inner side of the vertical guide rail and is rotatably sleeved on the vertical guide wheel shaft fixedly connected to the stator frame; during the movement of the mover frame relative to the stator frame, the horizontal guide wheel and the horizontal guide rail have rolling friction, and the vertical guide wheel and the vertical guide rail have rolling friction, respectively constraining the movement of the mover frame in the normal direction of the coronal plane and the normal direction of the sagittal plane of the carrying system; A first limit block and a second limit block are respectively provided at the upper portion of the mover frame and at corresponding positions of the stator frame. When the mover frame reaches the maximum downward displacement relative to the stator frame, the lower portion of the first limit block conflicts with the upper portion of the second limit block.

3. The carrying system according to claim 1, characterized in that: A locking mechanism is also provided between the mover frame and the stator frame and close to the lower part of the stator frame, and the locking mechanism includes a locking plug and a locking hook; the locking plug is rotatably sleeved on a locking plug shaft fixedly connected to the stator frame, and the locking hook is rotatably sleeved on a locking hook shaft fixedly connected to the stator frame, a first slot matching one end of the locking plug is provided on the locking hook, and a second slot matching one end of the locking hook away from the locking hook shaft is provided at the lower part of the mover frame facing the stator frame; when one end of the locking hook is inserted into the second slot and one end of the locking plug is inserted into the first slot, the mover frame and the stator frame are in a locked state; when one end of the locking plug is disengaged from the first slot and one end of the locking hook is disengaged from the second slot, the mover frame and the stator frame are in an unlocked state.

4. The carrying system according to claim 1, characterized in that: The transmission unit further comprises an auxiliary gear, which is rotatably sleeved on an auxiliary gear shaft fixed to the side of the mover frame facing the stator frame, and the auxiliary gear and the gear are arranged on the left and right sides of the rack.

5. The carrying system according to claim 1, characterized in that: The elastic element is a nonlinear elastic element, which is composed of a first sub-coil spring and a second sub-coil spring connected in series through the stiffness adjustment component, the first sub-coil spring is arranged closer to the central axis than the second sub-coil spring, and each sub-coil spring is a linear coil spring, or a nonlinear coil spring, or one of them is a linear coil spring and the other is a nonlinear coil spring; the nonlinear coil spring is a planar spiral spring formed by a plurality of coil spring segments connected end to end in sequence and integrally formed, and the stiffness of two adjacent coil spring segments is different; The stiffness adjustment assembly includes a first stiffness adjustment mechanism and a second stiffness adjustment mechanism, the first stiffness adjustment mechanism includes a first sub-coil spring locking piece and a first sub-coil spring driving frame fixedly connected to the central axis, the second stiffness adjustment mechanism includes a second sub-coil spring locking piece and a second sub-coil spring driving frame, each sub-coil spring driving frame can be rotated relative to the frame body and is respectively fixedly connected to the outer ends of the first sub-coil spring and the second sub-coil spring; each sub-coil spring locking piece respectively includes a ratchet pawl mechanism and a matching stop switch and a reset spring, each ratchet pawl mechanism shares a ratchet shaft, the ratchet shaft is coaxially arranged with the central axis and is rotatably connected to the frame body, a coil spring inner end adjustment piece is provided at the end of the ratchet shaft away from the central axis, the ratchet shaft is rotated by the coil spring inner end adjustment piece to adjust the inner end angle of each sub-coil spring to achieve pre-tightening or unloading of the inner end of each sub-coil spring, the first ratchet pawl mechanism is connected to The second ratchet pawl mechanism is connected between the inner end of the second sub-coil spring and the lower end surface of the second sub-coil spring driving frame; each reset spring always remains in a compressed state, used to provide a force for the corresponding stop pawl to approach the direction of each ratchet; during the stiffness adjustment process of the elastic element, the first sub-coil spring locking piece remains in a locked state with the second sub-coil spring driving frame according to the instruction of the control unit, so as to realize the series connection of the first sub-coil spring and the second sub-coil spring, and the stop switch in the second sub-coil spring locking piece increases or decreases the working turns of the first sub-coil spring and the second sub-coil spring at the same time according to the instruction of the control unit until the load torque, the torque of the nonlinear elastic element and the output torque of the drive motor are balanced, and the control unit controls all the stop switches to lock the inner ends of the first sub-coil spring and the second sub-coil spring at the same time.

6. The carrying system according to claim 5, characterized in that The first sub-coil spring is provided with P coil spring segments, and the second sub-coil spring is provided with Q coil spring segments, where P and Q are both positive integers greater than or equal to 1. When the number of segments of the sub-coil spring is 1, the sub-coil spring is a linear coil spring, and when the number of segments of the sub-coil spring is greater than 1, the sub-coil spring is a nonlinear coil spring; The nonlinear elastic element is designed according to the following steps: the given working curve of the adaptive drive module is divided into S segments, the working curve of the adaptive drive module is the functional relationship between the rotation angle of the central axis and the torque output through the external terminal, the total number of segments of the nonlinear elastic element is taken as S, that is, S=P+Q, and the first coil spring segment is located at the outer ring of the first sub-coil spring; the i-th segment working curve and its slope are respectively used as the working curve and stiffness of the i-th coil spring segment, i=1,2,...,S, and the i-th coil spring segment is designed according to the industry standard JB / T7366-1994 to obtain the parameters of the i-th coil spring segment, including elastic modulus E, section thickness h, section width b and unfolded length l.

7. The carrying system according to claim 5, characterized in that: The first ratchet pawl mechanism comprises a first ratchet rotatably sleeved on the ratchet shaft, and a first positive stop pawl and a first negative stop pawl matched with the first ratchet through a tooth portion, the inner end of the first sub-coil spring is fixedly connected to the first ratchet, and one end of the first positive stop pawl and the first negative stop pawl away from their respective tooth portions are rotatably connected to the lower end surface of the second sub-coil spring driving frame, a first positive return spring and a first positive stop switch are provided between an end of the first positive stop pawl close to its tooth portion and the lower end surface of the second sub-coil spring driving frame, and a first negative return spring and a first negative stop switch are provided between an end of the first negative stop pawl close to its tooth portion and the lower end surface of the second sub-coil spring driving frame; The second ratchet pawl mechanism comprises a second ratchet wheel fixedly sleeved on the ratchet shaft, and a second positive stop pawl and a second negative stop pawl matched with the second ratchet wheel through a tooth portion, the inner end of the second sub-coil spring is fixedly connected to the second ratchet wheel, and one end of the second positive stop pawl and the second negative stop pawl away from their respective tooth portions are rotatably connected to the lower end surface of the top cover of the frame body, a second positive return spring and a second positive stop switch are provided between one end of the second positive stop pawl close to its tooth portion and the lower end surface of the top cover of the frame body, and a second negative return spring and a second negative stop switch are provided between one end of the second negative stop pawl close to its tooth portion and the lower end surface of the top cover of the frame body; During the adjustment process of the elastic element, the first ratchet and the second coil spring drive frame remain in a locked state, and at most only one of the two stop pawls matching the second ratchet is in contact with the tooth portion of the second ratchet; when the load torque, the torque of the elastic element and the output torque of the drive motor are balanced, the two stop pawls matching the same ratchet are both in contact with the tooth portion of the ratchet.

8. The carrying system according to claim 1, characterized in that: The elastic element is a single nonlinear coil spring formed by connecting a plurality of coil spring segments end to end in sequence and integrally formed, and the stiffness of two adjacent coil spring segments is different; The stiffness adjustment assembly includes a stiffness adjustment mechanism, which includes a coil spring inner end adjustment member, a coil spring locking member and a coil spring driving frame fixedly connected to the central axis; the coil spring inner end adjustment member is arranged at the center of the top cover of the frame body, and is used to adjust the inner end rotation angle of the nonlinear coil spring to achieve pre-tightening or unloading of the inner end of the nonlinear coil spring; the coil spring driving frame can rotate relative to the frame body and is fixedly connected to the outer end of the nonlinear coil spring; the coil spring locking member includes a ratchet pawl mechanism and a matching stop switch and a reset spring, and the ratchet pawl mechanism is connected between the inner end of the nonlinear coil spring and the lower end surface of the top cover of the frame body; each reset spring is always kept in a tensioned state, and is used to provide a force for the stop pawl to approach the ratchet direction; During the stiffness adjustment process of the nonlinear coil spring, the stop switch allows the ratchet to move only in the set direction according to the command of the control unit, thereby increasing or decreasing the number of working turns of the nonlinear coil spring until a balance is reached among the load torque, the torque of the nonlinear coil spring and the output torque of the drive motor. The control unit then controls the stop switch to lock the inner end of the nonlinear coil spring.

9. The carrying system according to claim 8, characterized in that: The nonlinear coil spring is designed according to the following steps: the working curve of a given adaptive drive module is divided into S segments, the working curve of the adaptive drive module is a functional relationship between the rotation angle of the central axis and the torque output through the external terminal, the number of segments of the nonlinear coil spring is taken as S, and the first coil spring segment is located at the outer ring of the nonlinear coil spring; the i-th segment working curve and its slope are respectively used as the working curve and stiffness of the i-th coil spring segment, i=1,2,...,S, and the i-th coil spring segment is designed according to the industry standard JB / T7366-1994 to obtain the parameters of the i-th coil spring segment, including elastic modulus E, section thickness h, section width b and unfolded length l.

10. The carrying system according to claim 8, characterized in that: The ratchet pawl mechanism comprises a ratchet shaft coaxial with the central axis and a ratchet wheel fixedly sleeved on the ratchet shaft, and a positive stop pawl and a negative stop pawl matched with the ratchet wheel through a tooth portion, the top end of the ratchet shaft is rotatably connected to the frame body, the inner end of the nonlinear coil spring is fixedly connected to the ratchet shaft, the ends of the positive stop pawl and the negative stop pawl away from their respective tooth portions are rotatably connected to the lower end surface of the top cover of the frame body, the positive return spring and the positive stop switch are provided between the end of the positive stop pawl close to its tooth portion and the lower end surface of the top cover of the frame body, and the negative return spring and the negative stop switch are provided between the end of the negative stop pawl close to its tooth portion and the lower end surface of the top cover of the frame body; During the adjustment process of the nonlinear coil spring, at most only one of the two stop pawls cooperating with the ratchet wheel is in contact with the teeth of the ratchet wheel; when the load torque, the torque of the coil spring and the output torque of the drive motor are balanced, the two stop pawls cooperating with the ratchet wheel are both in contact with the teeth of the ratchet wheel.

11. The carrying system according to claim 1, characterized in that: The elastic element is a nonlinear elastic element, which is composed of a first sub-coil spring and a second sub-coil spring connected in parallel through the stiffness adjustment component and having the same number of working turns, the first sub-coil spring is arranged closer to the central axis than the second sub-coil spring, and each sub-coil spring is a linear coil spring, or a nonlinear coil spring, or one of them is a linear coil spring and the other is a nonlinear coil spring; the nonlinear coil spring is a planar spiral spring formed by a plurality of coil spring segments connected end to end in sequence and integrally formed, and the stiffness of two adjacent coil spring segments is different; the stiffness adjustment component includes a first stiffness adjustment mechanism and a second stiffness adjustment mechanism, and a partition fixedly connected to the frame body is provided in the frame body; The first stiffness adjustment mechanism includes a first sub-coil spring locking piece and a first sub-coil spring fixing frame, the first stiffness adjustment mechanism and the first sub-coil spring are located on the side of the partition facing the central axis, the second stiffness adjustment mechanism includes a second sub-coil spring locking piece and a second sub-coil spring fixing frame, the second stiffness adjustment mechanism and the second sub-coil spring are located on the side of the partition facing away from the central axis; each sub-coil spring locking piece includes a ratchet pawl mechanism and a matching stop switch and a reset spring, each ratchet pawl mechanism shares a ratchet shaft, the ratchet shaft is coaxial with the central axis and fixedly connected and rotatably connected to the frame body, the first ratchet pawl mechanism is connected to the first A second ratchet pawl mechanism is connected between the outer end of a sub-coil spring and the lower end surface of the partition, and between the outer end of the second sub-coil spring and the lower end surface of the top cover of the frame body; each reset spring is always kept in a compressed state, and is used to provide a force for the corresponding stop pawl to approach the direction of each ratchet; in the process of adjusting the elastic element, each stop switch allows each ratchet to move only in the same set direction according to the instruction of the control unit, so that the working turns of the two sub-coil springs are increased or decreased, until the load torque, the torque of the elastic element and the output torque of the drive motor are balanced, and the control unit controls the corresponding stop switch to lock the outer ends of the two sub-coil springs.

12. The carrying system according to claim 11, characterized in that: The nonlinear elastic element is designed as follows: Divide the given working curve of the adaptive driving module into S segments, wherein the working curve of the adaptive driving module is a functional relationship between the rotation angle of the central axis and the torque output through the external terminal; Assume that the number of coil segments contained in the first sub-coil spring is P, and the number of coil segments contained in the second sub-coil spring is Q, and both P and Q are positive integers greater than or equal to 1, and satisfy S≥P, S≥Q. When the number of coil segments of the sub-coil spring is 1, the sub-coil spring is a linear coil spring, and when the number of coil segments of the sub-coil spring is greater than 1, the sub-coil spring is a nonlinear coil spring; For the i-th section of the working curve, i=1,2,...,S, the torque at a certain rotation angle φ on the section of the working curve is taken as the sum of the torque of the first sub-coil spring and the torque of the second sub-coil spring at the rotation angle φ, and the slope of the working curve at the rotation angle φ is taken as the sum of the stiffness of the first sub-coil spring and the stiffness of the second sub-coil spring at the rotation angle φ, thereby obtaining the respective working curves of the first sub-coil spring and the second sub-coil spring within the rotation angle range corresponding to the i-th section of the working curve; According to the working curves of the first sub-coil spring and the second sub-coil spring, each coil spring segment in the first sub-coil spring and the second sub-coil spring is designed according to the industry standard JB / T7366-1994, and the parameters of each coil spring segment are obtained, including elastic modulus E, cross-sectional thickness h, cross-sectional width b and unfolded length l.

13. The carrying system according to claim 11, characterized in that: The first ratchet pawl mechanism includes a first ratchet rotatably sleeved on the ratchet shaft and a first positive stop pawl and a first negative stop pawl that cooperate with the first ratchet through a tooth portion, a first sub-coil spring fixing frame that is integrally formed with the first ratchet is provided on the outer periphery of the first ratchet, an inner end and an outer end of the first sub-coil spring are respectively fixedly connected to the ratchet shaft and the first sub-coil spring fixing frame, an end of the first positive stop pawl and the first negative stop pawl that are away from their respective tooth portions are rotatably connected to an end surface of the partition plate facing the first sub-coil spring fixing frame, a first positive return spring and a first positive stop switch are provided between an end of the first positive stop pawl that is close to its tooth portion and the partition plate, and a first negative return spring and a first negative stop switch are provided between an end of the first negative stop pawl that is close to its tooth portion and the partition plate; The second ratchet pawl mechanism comprises a second ratchet wheel rotatably sleeved on the ratchet shaft and a second positive stop pawl and a second negative stop pawl which cooperate with the second ratchet wheel through a tooth portion, a second sub-coil spring fixing frame which is integrally formed with the second ratchet wheel is provided on the outer periphery of the second ratchet wheel, an inner end and an outer end of the second sub-coil spring are respectively fixedly connected to the second ratchet shaft and the second sub-coil spring fixing frame, an end of the second positive stop pawl and the second negative stop pawl which are away from their respective tooth portions are rotatably connected to an end surface of the top cover of the frame body facing the second sub-coil spring fixing frame, a second positive return spring and a second positive stop switch are provided between an end of the second positive stop pawl which is close to its tooth portion and the top cover of the frame body, and a second negative return spring and a second negative stop switch are provided between an end of the second negative stop pawl which is close to its tooth portion and the top cover of the frame body; During the adjustment process of the elastic element, at most only one of the two stop pawls matching the same ratchet wheel is in contact with the teeth of the ratchet wheel; when the load torque, the torque of the elastic element and the output torque of the drive motor are balanced, the two stop pawls matching the same ratchet wheel are both in contact with the teeth of the ratchet wheel.

14. The carrying system according to claim 13, characterized in that: After the torque is balanced, if the carrier is required to continue to rotate an angle α along the original rotation direction due to the need of the working angle, the two stop pawls cooperating with each ratchet are first placed in a state opposite to that before the torque is balanced, so that the outer end of each sub-winding spring rotates an angle α, and the inner end of each sub-winding spring will follow the outer end of the sub-winding spring to rotate an angle α, and then the stop pawls are used to make each ratchet in a two-way locking state; After the torque is balanced, if the carrier is required to rotate an angle β in the opposite direction of the original rotation direction due to the need of the working angle, the two stopping pawls cooperating with each ratchet wheel are first placed in the same state as before the torque is balanced, and the driving motor is used to drive the carrier to rotate in the opposite direction of the original rotation direction to unload each sub-coil spring. Until the elastic torque of each sub-coil spring is zero, the driving motor is used to drive the carrier to continue to rotate an angle β in the opposite direction of the original rotation direction, thereby pushing the outer end of each sub-coil spring to rotate an angle β in the opposite direction of the original rotation direction of the carrier. At this time, the stopping pawl is first used to make each ratchet wheel in a two-way locking state, and then the two stopping pawls cooperating with each ratchet wheel are placed in the same state as before the torque is balanced, the load torque is connected, the inner end of each sub-coil spring rotates in the original rotation direction of the carrier, each sub-coil spring is compressed and deformed, and the outer end of each sub-coil spring rotates in the opposite direction of the original rotation direction of the carrier by an angle β, so that the torque is balanced again, and finally the stopping pawl is used to make each ratchet wheel in a two-way locking state.

15. The carrying system according to claim 5, 8 or 11, characterized in that: The control unit includes a circuit board and a main controller, an angle sensor and a current sensor arranged on the circuit board. The circuit board is fixedly connected to the frame body. The angle sensor is used to measure the angle of the central shaft in real time. The current sensor is used to measure the current of the drive motor in real time. The main controller is used to control the drive motor and each stop switch according to the angle signal of the central shaft and the current signal of the drive motor.

16. The carrying system according to any one of claims 5 to 13, characterized in that: The carrying system further comprises a handle matched with the gear and a power module connected with the driving motor, so that the carrying system has a manual power generation function; When manual power generation is required, the mover frame together with the adaptive drive module and the package body thereon are detached from the upper part of the stator frame, and the control unit controls each stop switch to separate all the stop pawls from the teeth of the corresponding ratchet wheels. The gear is rotated by the handle to generate current for the drive motor, which is stored in the power module.

17. The carrying system according to any one of claims 1 to 14, characterized in that: The control unit is also used to perform four-loop control on the drive motor according to the acceleration of the mover frame, so that the mover frame and the package are maintained at the target position while adaptively adjusting the size of different step frequencies, and the step frequency size is equivalent to the oscillation frequency of the acceleration of the mover frame; the four-loop control is to add an acceleration loop on the basis of the FOC method, and the acceleration loop is used to fit the deviation between the current position of the mover frame and its target position through a PID control algorithm according to the deviation between the current acceleration of the mover frame and its target acceleration, and obtain the target angle of the drive motor according to the deviation of the target position, and use the target angle as the input of the FOC method. After calculation by the FOC method, the target current value of the drive motor to maintain or reach the target angle is obtained.

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