CN115302493B - Friction damping driver and exoskeleton - Google Patents

Abstract

The present invention discloses a friction damping driver, comprising a winch and a driving device for driving the winch to rotate, wherein a force transmission component for transmitting power assistance is wound around the winch; a locked component arranged on the winch, a locking component and a first friction component arranged at the output end of the driving device, and a second friction component arranged on the locking component and capable of interacting with the first friction component to generate friction force; when the driving device does not provide driving force and rotates in the opposite direction relative to the winch, the locking component releases the locked component under the action of the friction force between the first friction component and the second friction component, so that the driving device and the winch are unlocked in both directions; when the driving device provides driving force and drives the locking component to rotate in the forward direction, the locking component will be quickly unidirectionally locked by the locked component under the action of the friction force generated between the second friction component and the first friction component, thereby unidirectionally locking the driving device and the winch.

Description

Friction damping actuator and exoskeleton

Technical Field

The invention relates to a driving device of a power-assisted exoskeleton, in particular to a friction damping driver, and a power-assisted exoskeleton having the friction damping driver.

Background Art

Power-assisted exoskeleton is a new type of modern wearable device that integrates multiple information, control systems and sensor systems, providing corresponding control functions for the wearer of the power-assisted exoskeleton, and can assist the wearer to complete various tasks more efficiently (for example, load-bearing, carrying, etc.). At present, the driving methods of power-assisted exoskeletons include hydraulic power and motor power. Among them, motor power technology is the most commonly used driving method.

In order to reduce the mass and inertia of the exoskeleton at the execution end (such as ankle joint, knee joint or arm, etc.), usually when designing the exoskeleton, a flexible force transmission component in the form of a pull line is used to convert the torque of the motor into a pulling force and flexibly transmit it to the exoskeleton execution end. However, since the pull line (including steel wire, rope or braided belt, etc.) can efficiently transmit the pulling force, it cannot transmit the thrust. Therefore, in order to ensure that the pull line can be reliably pulled out and retracted, it is preferred to connect an elastic element, such as a spring, in series from the drive mechanism to the actuator, so as to obtain a corresponding series elastic drive device. The advantage of the series elastic drive device is that the drive device itself has mechanical rigidity, and the power torque of the motor can be flexibly transmitted to the exoskeleton execution end through the series spring. If the movement intention of the human body does not match the predetermined position of the exoskeleton, the system inherently allows a deviation between the predetermined position of the exoskeleton and the actual position of the exoskeleton actuator. But its disadvantage is that the series mechanism can reduce the response frequency of the system as a whole, and when the human body needs a larger power, the series mechanism always has a certain delay. In view of this, a parallel elastic driver came into being. The driver and the elastic mechanism are arranged in parallel at the input end of the cable pulling mechanism, and a centrifugal clutch is arranged between the driver and the winch of the cable winding. When the driver provides assistance, the driver is connected to the winch of the cable pulling mechanism through the centrifugal clutch. When the driver stops providing assistance, the connection between the driver and the winch of the cable pulling mechanism is disconnected through the centrifugal clutch. Although, when the driver is not working, the winding force transmission components in the driver and the cable pulling mechanism, i.e., the winch of the cable pulling, are completely unlocked, the engagement condition of the centrifugal clutch is that the output end of the driver (such as a motor) must reach a sufficiently large speed so that the centrifugal force of the pawl in the centrifugal clutch can overcome the reset force of the pawl, thereby engaging with the ratchet on the winch to achieve torque transmission from the motor to the winch. This makes the timing of the centrifugal clutch engagement delayed when the speed of the driver, such as the output end of the motor, is not high, and because the output end has a large speed, the centrifugal clutch engagement moment will bring a large impact force to the winch.

Summary of the invention

The object of the present invention is to provide a friction damping driver for a power-assisted exoskeleton and an exoskeleton, which can partially solve or alleviate the above-mentioned deficiencies in the prior art and improve user experience.

In order to partially solve the above problems, the technical solution adopted by the present invention is as follows:

A first aspect of the present invention is to provide a friction damping driver, comprising a capstan and a driving device for driving the capstan to rotate, wherein the capstan is wound with a force transmission component for transmitting power assistance; the driver is characterized in that the driver further comprises a locked component arranged on the capstan, a locking component and a first friction component arranged at an output end of the driving device, and a second friction component arranged on the locking component and capable of interacting with the first friction component to generate friction force;

When the driving device does not provide driving force and rotates in the opposite direction relative to the winch, the second friction component rotates relative to the first friction component and generates friction between the first friction component and the second friction component, so that under the action of the friction between the first friction component and the second friction component, the locking component releases the locked component, so that the driving device and the winch are unlocked in both directions;

When the driving device provides driving force and drives the locking component to rotate in the forward direction, the second friction component rotates relative to the first friction component and generates friction between the first friction component and the second friction component. Therefore, under the action of the friction generated between the first friction component and the second friction component, the locking component quickly unidirectionally locks the locked component, thereby unidirectionally locking the driving device and the winch.

In some embodiments, the first friction member and the second friction member are magnetic elements that can attract each other.

In some embodiments, the second friction component is a magnetic element having magnetic force, and the first friction component is a polar element that can be attracted by the magnetic force of the magnetic element.

In some embodiments, the first friction component is used to provide a friction surface, and the second friction component is a friction block connected to the locking component via an elastic return member and capable of sliding relative to the first friction component to generate friction force.

In some embodiments, the locked component is a ratchet, the locking component is a pawl, and the tooth shape of the pawl and the tooth shape of the ratchet are both forward and reverse symmetric.

In some embodiments, the friction damping driver further includes: an introduction mechanism for introducing the force transmission component into the wire tube in the wire tube mechanism, the introduction mechanism including: a first correction component arranged on the wire tube inlet side, for radially correcting the outlet direction of the force transmission component so that the force transmission component coincides with the tangential direction of the wire tube end in the radial direction of the capstan; and a second correction component arranged on the wire tube inlet side, for axially correcting the outlet direction of the force transmission component, or axially correcting the wire tube end so that the wire tube end is tangent to the end winding position of the force transmission component.

In some embodiments, the first alignment assembly includes at least one radial guide wheel mounted on a capstan mount.

In some embodiments, the second alignment assembly includes at least two axial guide wheels mounted on a capstan mount.

In some embodiments, the second correction assembly includes: an axial slide rail providing an axial movement path for the wire tube, and at least two axial guide wheels movable on the axial slide rail along the axial movement path.

In some embodiments, the second correction assembly further comprises: a plurality of axial needle bearings for bearing the pressure of the end of the wire tube and dispersing the pressure to the axial slide rail.

In some embodiments, the friction damping drive also includes an elastic energy storage mechanism connected in parallel with the driving device at the force input end of the force transmission component. The elastic energy storage mechanism stores force when the pull wire is pulled out, and when the driving device stops providing driving force, the elastic energy storage mechanism releases elastic potential energy to drive the winch to recover the pull wire.

In some embodiments, the driving device is a motor.

In some embodiments, the force transmission component is one of a metal wire, a rope, and a braided belt.

A second aspect of the present invention is to provide a power-assisted exoskeleton comprising the above-mentioned friction damping drive.

The benefit of the present invention is that: when the drive device does not need to work, that is, does not provide driving force/assistance, the driver of the present invention can unlock the locking component (for example, quickly retract the pawl) through the friction force generated between the first friction component at the output end of the drive device and the second friction component on the locking component, so that the drive device can be completely unlocked from the capstan (that is, unlocked in both forward and reverse directions), avoiding the problem that when the drive device stops assisting, the drive device itself is converted into a damping component, causing the wearer to feel continuous motion damping when wearing the power-assisted exoskeleton for exercise (and no assisting is provided), thereby It ensures the smoothness of the free movement of the corresponding joints of the wearer when no assistance is needed; and when the drive device needs to engage with the capstan, the friction force generated between the first friction component at the output end of the drive device and the second friction component on the locking component (for example, the friction force generated by the magnetic force between the two friction components, or the friction force generated by the pressure between the two friction components) enables the locking component to quickly lock the locked component in one direction (for example, the pawl is quickly extended and quickly engaged with the ratchet wheel of the capstan), thereby connecting the drive device to the capstan, and then realizing the torque transmission from the drive device to the capstan. Compared with the existing centrifugal clutch parallel elastic drive, this solution can avoid the problems of delayed timing of the engagement of the pawl and the ratchet wheel due to the pawl having to reach a higher speed to be thrown out under the action of centrifugal force to achieve clutch locking, and the greater impact force on the capstan at the moment of engagement.

On the one hand, the driver of the present invention realizes the remote flexible transmission of power through flexible force transmission components (such as ropes) and wire tube mechanisms, so that the driver and the actuator can be set separately, and the heavier components are concentrated above the waist, so that components with a certain weight, such as the drive device, and the winch in the pull-wire mechanism, the battery control system, etc. can be placed on the wearer's waist, or above the waist, thereby avoiding the problem in the prior art that the drive motor is directly installed on the actuator, causing the wearer to feel that the device is bulky or even restricting the wearer's freedom of movement; and the power assistance provided by the drive device and/or the recovery force provided by the elastic energy storage mechanism can be transmitted to at least one actuator through the pull wire, so that one drive device drives multiple actuators, avoiding the prior art that a drive device is installed for each actuator, resulting in an increase in the self-weight of the power-assisted exoskeleton system, thereby affecting the wearer's walking gait. In other words, the drive device of the present invention is not only simpler in structure, but also reduces the power assistance. The system deadweight of the exoskeleton reduces the negative impact of the deadweight of the exoskeleton device on the wearer's lower limb walking gait, thereby improving the wearer's user experience; and by simultaneously connecting an elastic energy storage component (such as a coil spring) and a drive device (such as a motor) in parallel at the capstan end, the flexible force transmission component (such as a rope) can retract the excess rope to the capstan end regardless of whether the drive is assisted, avoiding problems such as entanglement of loose ropes; by providing a one-way clutch (or a one-way locking mechanism) between the motor and the capstan, the elastic energy storage component (such as a coil spring mechanism) only needs to overcome the tension of the flexible force transmission component (such as a rope) to retract the excess flexible force transmission component (such as a rope), so that even if the drive device (such as a motor) does not work, the drive device (such as a motor) will not become a damping member for the coil spring to retract the rope (because the motor usually uses a brushless reduction motor, when the motor is not working, due to the tooth slot torque of the brushless motor and the reduction mechanism, the motor has a large damping force when it is not working).

On the other hand, if only a centrifugal clutch or a one-way pawl ratchet mechanism is provided between the drive device and the winch, 1) since the centrifugal clutch requires a relatively high rotation speed to engage, the instantaneous impact of engagement is relatively large; 2) in the one-way pawl ratchet mechanism, when the drive device, such as the motor, is not working and the rope has no additional tension, although the coil spring can achieve rope retraction with a relatively small torque, when the flexible force transmission component (such as the rope) is passively pulled out (for example, the human body joint is bent, causing the rope to be pulled out), since the one-way pawl can only be unlocked in one direction, the flexible force transmission component (such as the rope) needs to overcome the coil spring energy storage torque and the damping force of the motor at the same time, unless the motor actively follows the winch to send out the rope. Based on this, the present invention adopts a friction-damped pawl-rachet mechanism between the drive device and the winch. When the motor does not need assistance, the motor only needs to rotate a certain angle in the opposite direction relative to the assistance direction, and the locking component (for example, the pawl) will be retracted under the action of friction, and will not engage the winch again during the entire period when the motor is not working. Therefore, the system becomes a purely mechanical winding mechanism of the winch and the winding spring. No matter whether the rope is pulled out or retracted, there is no need to overcome the motor damping force; and when motor assistance is needed, the motor rotates forward, and the locking component (for example, the pawl) will quickly engage the ratchet driven by friction, thereby allowing the motor to intervene in the entire transmission system, and the torque of the motor can be efficiently transmitted to the winch, thereby retracting the rope for strong assistance.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a partial cross-sectional view of a driver according to an exemplary embodiment of the present invention;

FIG2 is an exploded schematic diagram of some components of a driver from a first viewing angle according to an exemplary embodiment of the present invention;

FIG3 is an exploded schematic diagram of some components of a driver according to a second viewing angle of an exemplary embodiment of the present invention;

FIG4 is a schematic diagram of a driver according to an exemplary embodiment of the present invention when the pawl and the ratchet wheel are not engaged;

FIG5 is a schematic diagram showing the engagement of a pawl and a ratchet wheel in a driver according to an exemplary embodiment of the present invention;

FIG6 is a partial perspective cross-sectional view of a driver when a pawl and a ratchet wheel are not engaged according to an exemplary embodiment of the present invention;

FIG7 is a partial perspective cross-sectional view of a pawl and a ratchet wheel in a driver according to an exemplary embodiment of the present invention when the pawl and the ratchet wheel are engaged;

FIG8 is a schematic diagram of assembling a first correction component and a second correction component in a driver according to an exemplary embodiment of the present invention;

FIG9 is a schematic diagram showing the cooperation between the central axis guide wheel, the cable and the cable tube of the driver according to an exemplary embodiment of the present invention;

FIG10 is a schematic diagram of a slider mechanism in a driver according to an exemplary embodiment of the present invention;

FIG11 is a partial exploded schematic diagram of a slider mechanism in a driver according to an exemplary embodiment of the present invention;

FIG12 is a schematic diagram showing a central line pipe end of a driver according to an exemplary embodiment of the present invention sliding to the bottom;

FIG13 is a schematic diagram showing that the end of the wire tube slides to the top in the slider mechanism of the driver according to an exemplary embodiment of the present invention;

FIG14 is a schematic structural diagram of a second correction component in a driver according to another exemplary embodiment of the present invention;

FIG15 is a schematic diagram showing the cooperation between the axis guide wheel, the wire tube and the pull wire in the second correction assembly in FIG14;

FIG16 is a schematic diagram of an elastic friction damping mechanism in a driver according to an exemplary embodiment of the present invention;

FIG. 17 is a schematic diagram of a driver in which a pawl is assembled in a counterclockwise direction according to an exemplary embodiment of the present invention.

11-motor, 110-output disk; 12-capstan mounting seat, 120-slider mounting seat; 139-ratchet, 132-pawl, 1320-friction block mounting hole, 133-pawl mounting seat, 134-magnet mounting hole, 135-friction block, 136-spring, 137-pawl end cover, 138-bearing mounting seat; 14-pull wire (force transmission component); 15-wire tube, 16-capstan, 162-slotted shaft; 17-coil spring mounting seat; 18-coil spring, 185-coil spring cover, 186-magnetic angle meter, 187-radial magnet, 188-magnetic angle meter end cover; 30-iron sheet mounting seat, 31-iron sheet, 32-magnet; 40-radial guide wheel mounting shaft, 41-radial guide wheel, 42-axial guide wheel, 45-slider rail, 46-wire tube slider mechanism, 47-slider end cover, 461-slider, 462-wire tube end mounting seat, 463-first cylindrical pin, 464-axial guide wheel mounting seat, 465-needle bearing, 466-second cylindrical pin, 467-mounting cavity.

DETAILED DESCRIPTION

The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without creative work belong to the scope of protection of the present invention. It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly. In addition, in the present invention, the description of "first", "second", etc. is only used for descriptive purposes, and cannot be understood as indicating or implying its relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

The "elastic energy storage mechanism" in this article refers to an elastic energy storage mechanism, such as a coil spring/spring, which provides a recovery force to the cable that transmits the assistive force in the assistive exoskeleton to tighten the cable when the drive device stops providing assistive force.

In this article, "actuator" refers to a mechanism that performs corresponding actions or realizes corresponding functions under the drive of a driving device, for example, a mechanism used to assist the wearer's joints, and which moves under the drive of the driving device, specifically, such as the knee joints, ankle joints, hip joints, etc. in an assisted exoskeleton device.

In this article, "parallel connection" means that the force (for example, assisting force or recovery force) output ends of the above-mentioned drive device and the above-mentioned elastic energy storage mechanism are connected to the input end of the winch/pull cable to provide a certain force (such as assisting force or recovery force) to the pull cable. For example, the motor and the coil spring as the elastic energy storage mechanism are connected to the winch around the pull cable in synchronous rotation. When the motor is working, the motor and the coil spring pull the pull cable at the same time to apply assisting force to the knee exoskeleton mechanism and the ankle exoskeleton mechanism; when the motor stops working (such as the battery is exhausted or the motor is intentionally stopped), the coil spring can still pull the pull cable, so that the pull cable is always in a taut state during the operation of the exoskeleton mechanism, thereby preventing the pull cable from being in a state of free relaxation, causing the risk of mechanical failure caused by the pull cables at the winch being entangled with each other, thereby greatly reducing the incidence of safety accidents.

In this article, "pull wire" refers to various flexible linear components used to transmit power/tension, also known as flexible force transmission components, such as linear or tubular steel wires, ropes, or filaments, or belts or strips of braided belts, etc.

In this article, "wire tube" refers to the pipe that covers or is set outside the pull wire, with both ends fixed and incompressible, which provides a movement path for the pull wire to achieve the transmission of power/tension. In this article, the pipes between the various modules in the drive or exoskeleton are collectively referred to as wire tube mechanisms.

In this article, "input end" refers to the end of each component that receives force, also known as the force input end. For example, the end of the cable that receives the assist force output by the drive device, or the end that receives the recovery force generated/output by the elastic energy storage mechanism; or the end of the actuator that receives the assist force transmitted by the cable.

The "output end" in this article refers to the end of each component that outputs force, also known as the force output end. For example, the end of the pull wire connected to the actuator outputs the force provided by the drive device to the input end of the actuator (i.e., the end that receives the force).

In this article, "radial" means that when a certain component is used as a reference component, the direction extending perpendicular to the center line or center axis of the reference component is the radial direction, and when multiple reference components are arranged along the radial direction, the center line or center axis of each reference component is parallel to the center line or center axis of the reference component. For example, when a capstan is used as a reference component, the direction extending perpendicular to the center line or center axis is the radial direction. For another example, when a pawl mounting seat is used as a reference component, the direction extending perpendicular to the center line or center axis is the radial direction, and the center lines or center axes of multiple pawls arranged along the radial direction are all parallel to the center line or center axis of the pawl mounting seat.

In this article, "axial direction" means that when a certain component is used as a reference component, the center line or center axis of the reference component is used as the axial direction, and when multiple reference components are arranged along the axial direction, the center line or center axis of each reference component is parallel to the center line or center axis of the reference component and is coaxial. For example, when a capstan is used as a reference component, the direction of its center line or center axis is the axial direction, and the center lines or center axes of multiple pawls and ratchet wheels arranged along the axial direction are all coaxial with the center line or center axis of the pawl mounting seat.

"One-way locking" in this article means that the power source (for example, the output disk of the motor) and the winch of the cable pulling mechanism can move freely in one relative rotation direction; while in the opposite relative movement, the two are engaged through the pawl and ratchet wheel, thereby connecting and locking the power source and the winch.

In this article, "polarity" means that a certain component or element (or part of the component/element) has a certain attractive force (such as magnetic force); or the component or element (or part of it) can be attracted by the magnetic attraction (such as magnetic force) of a specific thing (or part of a specific thing). Correspondingly, "magnetic attraction" means that two or more components/elements with magnetic attraction attract each other, or a component/element is attracted by a component/element with magnetic attraction.

In this article, "opposite magnetic poles" refers to the magnetic poles of two magnetic elements/components being opposite poles that attract each other. For example, the magnetic pole of one element/component is the north pole (N pole) and the magnetic pole of the other element/component is the south pole (S pole).

The "end winding position" herein refers to the position where the pull line is about to pass through the winch and enter the wire tube portion after being wound on the winch.

In this article, "positive and negative symmetrical design" means that the tooth shape adopts a symmetrical structure, so that the same parts can be used to adjust the clockwise or counterclockwise power-assist direction of the driver by adjusting the assembly direction. For example, when the pawl is assembled in a clockwise direction (as shown in the direction of the pawl in Figure 5), the clockwise rotation of the motor will cause the pawl to be extended under friction, thereby engaging the capstan and driving the capstan to rotate clockwise to retract the flexible rope for efficient power assistance. In this assembly mode, clockwise rotation is called forward rotation (that is, the power-assist direction), and counterclockwise rotation is called reverse rotation. It can be seen that when the motor rotates in the opposite direction by a certain angle, the pawl will be driven by friction (as shown in Figure 5, the friction generated by the magnetic force) to retract the drive device, such as the center of the motor output disk, thereby achieving two-way unlocking of the drive device, such as the motor and the capstan end.

On the contrary, if the pawl is assembled in the counterclockwise direction (as shown in the pawl direction in Figure 17), the counterclockwise rotation of the motor will cause the pawl to be extended (or stretched out) under the friction force. Therefore, in this mode, counterclockwise rotation is called positive rotation (also known as the power-assisting direction), and clockwise rotation is called reverse rotation.

In order to ensure the smooth free movement of the wearer's corresponding joints when the driving device stops assisting, the driving device can be completely unlocked from the capstan (unlocked in both forward and reverse directions) when the driving device does not need to work (or does not provide assistance), and when the driving device needs to engage with the capstan, the driving device and the capstan can engage quickly. As shown in Figures 1 to 17, the present invention provides a driver, including: a winch 16 and a driving device for driving the winch 16 to rotate, the winch 16 is wound with a pull wire (or flexible force transmission component) 14 for transmitting power assistance; it also includes an elastic energy storage mechanism connected in parallel with the driving device at the force input end of the force transmission component, the elastic energy storage mechanism stores force when the pull wire 14 is pulled out, and when the driving device stops providing driving force, the elastic energy storage mechanism releases elastic potential energy to drive the winch 16 to retract the pull wire; a friction force one-way locking transmission mechanism is arranged between the driving device and the winch 16, and the friction force one-way locking transmission mechanism includes: a locked component arranged on the winch, a locking component arranged at the output end of the driving device, and a friction damping assembly arranged between the driving device and the locking component.

In some embodiments, the friction damping assembly includes a first polarity element (serving as a first friction component) arranged at the output end of the driving device; and a second polarity element (serving as a second friction component) arranged on the locking component; and the first polarity element and the second polarity element attract each other, for example, magnetically attract each other; when the driving device does not provide driving force, the driving device rotates in the opposite direction of the assisting direction by a certain angle (as shown in Figure 4 or Figure 5, rotates counterclockwise by a certain angle), and under the action of the magnetic attraction between the first polarity element and the second polarity element, the locking component releases the locked component, so that the driving device and the winch are unlocked in both directions; when the driving device provides driving force and drives the locking component to rotate, under the action of the magnetic friction force generated by the magnetic attraction between the first polarity element and the second polarity element, the locking component quickly unidirectionally locks the locked component, thereby unidirectionally locking the driving device and the winch.

In some embodiments, the locked component and the locking component adopt a ratchet and pawl mechanism, wherein the ratchet 139 in the ratchet and pawl mechanism is set on the capstan 16, the pawl 132 is fixed on the output disk 110 of the driving device, and the first polarity element in the magnetic damping assembly is fixed to the periphery of the output disk of the driving device, and the second polarity element is fixed on the pawl 132 and corresponds to the first polarity element.

In some embodiments, the pawl 132 is connected to the output disk 110 of the motor 11 in synchronous rotation through the pawl mounting seat 133 (for example, the pawl mounting seat 133 can be fixed to the output disk of the motor 11 by a fixing member such as a screw), that is, the motor 11 drives the pawl 132 to rotate. In order to make the ratchet pawl stable during transmission, there are three pawls evenly arranged along the circumference. Of course, the number of pawls can be adjusted according to actual needs.

In some embodiments, the driving device is preferably a motor 11, and the pull wire 14 is preferably one of a metal wire, a rope, and a braided belt.

In some embodiments, the first polarity element is an annular iron sheet 31 (or other metal parts that can be attracted by magnetic elements), which is fixed to the periphery of the output disk 110 of the motor 11 through the iron sheet mounting seat 30 (that is, the first friction component is fixed and does not rotate with the output disk of the driving device); the second polarity element is a pawl magnet 32 (that is, a magnetic element), which is arranged at the tip of the pawl 132 near the ratchet tooth and above the iron sheet. Of course, the installation position of the magnet 32 can be adjusted according to actual needs, as long as it meets the following requirements: when the motor rotates, it can interact with the iron sheet to generate friction damping.

For example, when the motor 11 does not provide driving force, since the iron sheet 31 is fixed and the pawl magnet 32 has magnetic attraction, once the motor 11 rotates in the opposite direction by a certain angle and drives the pawl 132 to rotate in the opposite direction, at this time, under the action of the magnetic force, the pawl 132 is in a retracted state, that is, the pawl 132 is unlocked from the ratchet 139, so that the motor 11 and the capstan 16 are bidirectionally unlocked (that is, both the forward and reverse directions are unlocked); and when the motor 11 provides driving force and drives the pawl 132 to rotate, since the iron sheet 31 is attracted by the magnetic force of the pawl magnet 32, at this time, the magnetic force is converted into magnetic friction force, so that the pawl 132 is quickly extended and quickly meshes with the ratchet 139, thereby locking the ratchet 139 in one direction, that is, locking the motor 11 and the capstan 16 in one direction.

4 and 6, when the motor 11 and the capstan 16 need to be unlocked, regardless of whether the pawl 132 is currently engaged with the ratchet 139 on the capstan 16, the motor 11 only needs to rotate a certain angle in the counterclockwise direction in FIG. 4 (i.e., the opposite direction of the assisting direction) (the specific angle is determined by geometric parameters such as the meshing tooth shape, for example, the motor 11 rotates 5 to 10 degrees counterclockwise). Since the pawl magnet 32 on the pawl 132 is magnetically attracted to the iron sheet 31, the pawl 132 will rotate counterclockwise following the motor output disk 110 (i.e., the motor output disk 110 drives the pawl mounting seat 133, and the pawl mounting seat 133 drives the pawl 132 to rotate). rotation, at this time, the pawl magnet 32 generates a magnetic friction damping force F=μ*N along the rotation direction of the motor 11, wherein N is the magnetic force of the pawl magnet 32 adsorbed on the iron sheet 31, and μ is the sliding friction coefficient between the pawl magnet 32 and the iron sheet 31; since the pawl magnet 32 is installed in the pawl magnet mounting hole 134 at the front end of the pawl 132 close to the ratchet position, the magnetic friction damping force F generates two component forces on the pawl 132, one is the first component force F2 in the direction of the first connecting line between the rotation center O1 of the pawl 132 and the center O2 of the pawl magnet 32, and the other component force is the second component force F1 perpendicular to the direction of the first connecting line. Among them, the second component force F1 makes the pawl 132 rotate clockwise around its own rotation center O1, and then retracts the ratchet teeth of the pawl 132, completely unlocking the capstan 16, so that the motor 11 can remain completely stationary without the need for assistance, and the pawl 132 remains in a retracted state under the magnetic force of the pawl magnet 32 and the iron sheet 31. At this time, the drive is completely a passive spring energy storage rope retraction mechanism without the intervention of the motor 11.

Of course, in some embodiments, a plurality of pawl magnet mounting holes 134 may be provided at the front end (or tip) of each pawl 132 corresponding to the ratchet wheel to mount a plurality of pawl magnets, or the pawl magnets may be installed in some of the pawl magnet mounting holes according to actual needs.

Of course, in other embodiments, the first polarity element may also be a ring-shaped ratchet magnet, which is fixed to the periphery of the output disk 110 of the motor 11, that is, the first polarity element and the second polarity element both use ratchet magnets (that is, both use magnetic elements).

In some embodiments, the tooth shape of the pawl and the tooth shape of the ratchet wheel are both designed to be symmetrical in both positive and negative directions, so that the ratchet wheel, the pawl and the corresponding mounting seats can be used in both positive and negative directions, so that the ratchet wheel and the pawl can not only be installed in reverse directions, see Figure 17, but also only one mold is needed for the pawl, one mold is needed for the ratchet, and one mold is needed for the corresponding mounting seat during processing, which reduces the manufacturing cost, simplifies the processing technology, and reduces the difficulty of assembly. Among them, positive and negative directions refer to the power-assisting direction and the reverse direction of the driving device respectively. If the driving device is clockwise power-assisting, that is, the clockwise direction is the positive direction, then the counterclockwise direction is the reverse direction, for example, see Figures 4 and 5; if the driving device is counterclockwise power-assisting, that is, counterclockwise rotation is positive rotation, then the clockwise direction is the reverse direction. Similarly, see Figure 17, when counterclockwise rotation is positive rotation, clockwise rotation is reverse rotation.

Referring to Figures 5 and 7, when the motor 11 needs to engage (i.e., connect) with the capstan 16 and drive the capstan 16 to retract the pull wire 14, the motor 11 only needs to rotate a small angle in the clockwise direction (i.e., the power assist direction) in Figure 5 (similarly, the specific angle is determined by geometric parameters such as the meshing tooth shape), and the pawl 132 will rotate counterclockwise under the resistance of the pawl magnet 32 and the iron sheet 31, and the ratchet teeth of the pawl 132 will engage with the ratchet wheel 139 on the capstan 16, thereby completing the rigid transmission from the motor 11 to the capstan 16. Among them, the friction force generated by the sliding friction of the pawl magnet 32 on the iron sheet 31 is F’, and the friction force F’ will generate a third component force F3 along the tangent direction of the rotation direction of the pawl 132. It is the third component force F3 that makes the pawl 132 open outward and engage with the ratchet 139 on the capstan 16. Therefore, when the motor 11 rotates further clockwise, the torque of the motor 11 will be transmitted to the capstan 16 through the ratchet teeth of the pawl 132, and drive the capstan 16 to recover the pulled wire 14.

In some embodiments, the elastic energy storage mechanism uses a coil spring 18, and its installation direction is closely related to the direction of the pawl 132 and the winding direction of the cable 14 on the capstan 16. As shown in FIG5, when the motor 11 rotates clockwise, the pawl 132 engages with the ratchet 139 on the capstan 16. Therefore, from the perspective of FIG5, the winding direction of the cable 14 on the capstan 14 should be that when the capstan 16 rotates clockwise, the excess cable will be retracted, and the cable outlet direction of the cable 14 and the wire tube 15 is close to the lower end in FIG5. The installation direction of the coil spring 18 is also that when the central axis of the capstan 16 rotates clockwise, the coil spring 18 releases its capacity (the coil spring 18 retracts the excess cable by releasing energy).

In some embodiments, the winding direction of the pull wire 14, the orientation of the pawl 132, the rotation direction of the motor 11 when assisting, the wire outlet direction of the wire tube 15, and the installation direction of the coil spring 18 need to be consistent.

In some embodiments, the coil spring 18 acts on the winch 16; when the motor 11 provides driving force to the cable 14, the coil spring 18 stores energy; and when the motor 11 stops providing driving force to the cable 14, the coil spring 18 releases the stored elastic potential energy, and intends to provide a recovery force to the cable 14. Specifically, the outer ear of the coil spring 18 is fixed on the winch. For example, a coil spring mounting seat 17 is installed on the winch mounting seat by bolts and other fixing parts, and the outer ear of the coil spring 18 is fixed to the outer ear fixing groove on the coil spring mounting seat 17. Its inner ear is fixed on the rotating shaft of the coil spring 18. Specifically, a through hole is set in the center of the coil spring mounting seat 17 for the slotted rotating shaft 162 set in the center of the winch 16 to pass through, and the inner ear is inserted into the straight groove set on the slotted rotating shaft 162, wherein the slotted rotating shaft 162 also serves as the rotating shaft of the coil spring 18. Finally, the coil spring cover 185 is snapped on the coil spring mounting seat 17.

One end of the cable 14 is fixed on the capstan 16, and after being wound around the capstan 16 for several turns, it passes through the cable groove of the capstan mounting seat 12. The capstan mounting seat 12 is provided with a wire tube 15, and the cable 14 needs to pass through the wire tube 15. One end of the wire tube 15 is inserted into the wire tube sink groove of the wire tube mounting seat. A lead head 140 can be provided at the end of the cable 14, and the lead head 140 is placed in the lead head sink groove at the center of the capstan 16, thereby ensuring that the end position of the cable 14 is fixed to the capstan 16.

On the one hand, when the human limbs resist the elastic energy storage components and the motor damping to pull out the cable, they also have to exert greater muscle strength, which has a negative impact on the human body's gait. On the other hand, even when the motor is not working, the motor and the capstan can be completely unlocked, but the motor provides centrifugal force to make the pawl swing out and mesh with the ratchet wheel. The condition for the pawl to mesh with the ratchet wheel in the driver is that the output end of the motor reaches a certain speed, so that the centrifugal force of the pawl can overcome the tension of the pawl reset spring, and then close the ratchet wheel on the capstan to realize the torque transmission from the motor to the capstan. This will cause the timing of the pawl and ratchet meshing to lag, and with a higher speed, the meshing moment will bring a greater impact force to the capstan.

Therefore, in order to solve the above problems, in some embodiments, a magnetic damping component is provided between the driving device and the pawl, so that when the motor is not required to provide power assistance, the driving device only needs to rotate in the opposite direction of the power assistance by a certain angle, so that the second friction component rotates relative to the first friction component to generate friction between the first friction component and the second friction component, so that the pawl can be unlocked from the ratchet on the capstan under the action of the friction between the first friction component and the second friction component, thereby making the motor and the capstan completely unlocked in both directions, and realizing the effect of no motor load; and when the motor provides power assistance, the driving device rotates to drive the pawl to rotate (i.e., rotates forward in the power assistance direction), and drives the second friction component to rotate relative to the first friction component, so that the pawl can quickly engage with the ratchet under the action of the magnetic friction force between the two friction components, thereby realizing the rapid engagement of the driving device and the capstan, and the engagement time of the ratchet pawl mechanism is extremely short, so that the hysteresis time of the motor 11 and the capstan 16 is extremely short, thereby avoiding the delay of the driving force output; and because the engagement is under the action of the magnetic friction force, neither the ratchet nor the pawl will have a large rotation speed, thereby avoiding the impact force brought to the capstan at the moment of engagement.

In some embodiments, the driver further includes: an introduction mechanism for introducing the pull wire 14 (i.e., the force transmission component) into the wire tube 15. The introduction mechanism is specifically used to ensure that the outlet direction of the pull wire always coincides with the center line of the wire tube. Specifically, the introduction mechanism includes:

A radial correction component provided at the inlet side of the wire tube 15 is a first correction component for radially correcting the outgoing direction of the cable 14 passing through the capstan 16, so that the cable 14 coincides with the tangential direction of the end of the wire tube 15 in the radial direction of the capstan 16, see FIG8 ;

A second correction component is arranged on the inlet side of the wire tube 15, which is used to axially correct the outlet direction of the pull wire 14 from the capstan 16, or to axially correct the end of the wire tube 15, so that the end of the wire tube 15 is tangent to the end winding position of the pull wire 14 (or the outlet direction or center axis of the pull wire 14 coincides with the center axis of the wire tube), see Figure 9.

In some embodiments, referring to Figures 2, 3, 8 and 14, the first correction assembly includes: a radial guide wheel 41 mounted on the capstan mounting base 12, specifically, the radial guide wheel 41 is mounted on the capstan mounting base 12 through a radial guide wheel mounting shaft 40, and preferably, when setting the position of the radial guide wheel 41, it is considered that when the pull wire 14 is wound around the capstan 16, its outlet direction (or center axis) coincides with the center axis of the wire tube.

Of course, the radial guide wheel 41 can also be installed in multiple pieces according to actual needs. For example, if multiple layers of cable are wound on the capstan, the installation position of the radial guide wheel 41 can also be moved downward, but when the cable 14 is gradually pulled out, the cable 16 on the capstan 16 gradually decreases. In order to ensure that the cable outlet direction is consistent with the central axis of the wire tube 15, a radial guide wheel 41 can also be set above. Similarly, the installation position of the radial guide wheel can also be moved upward, and accordingly, a radial guide wheel needs to be set below it; of course, it can also be moved to the right.

In some embodiments, referring to Figures 14 and 15, the second calibration assembly includes: two axial guide wheels 42 mounted on the capstan mounting seat 12. Of course, the radial guide wheels 41 can also be installed in multiples according to actual needs.

By respectively arranging a radial guide wheel 41 and an axial guide wheel 42 in the capstan mounting seat, the radial and axial deviations of the pull wire 14 in the capstan 16 can be corrected after the pull wire 14 leaves the capstan 16, thereby ensuring that the extension direction of the pull wire entering the wire tube (or the wire outlet direction or the center axis) coincides with the tangent direction (or the center axis) of the end of the wire tube, thereby avoiding excessive wear of the pull wire and the wire tube.

In other embodiments, instead of performing axial correction on the pulling wire 14, the position of the wire tube 15 is axially corrected, that is, the wire tube 15 is corrected by a second correction component. Specifically, the second correction component is implemented by a slider mechanism 46 that can reciprocate axially along the capstan 16 relative to the capstan mounting seat 12. Specifically, the slider mechanism includes: an axial slide rail 43 that provides an axial movement path for the wire tube end, two axial guide wheels 42 that can move on the axial slide rail 43 along the axial movement path, and four axial needle bearings 465 for bearing the pressure of the wire tube end and dispersing the pressure to the axial slide rail.

Referring to FIG9 , when the number of winding turns of the cable 14 on the capstan 16 is large, the winding radius of the outermost cable 14 may be larger than the radius of the capstan 16, and the tangent direction of the end of the wire tube (or the center line of the end of the wire tube) is aligned with the tangent direction of the cable 14 wound on the innermost layer of the capstan 16. Therefore, at this time, the tangent directions of the outermost cable 14 and the end of the wire tube 15 will deviate, that is, the two do not correspond in the radial direction of the capstan. Therefore, by setting the radial guide wheel 41, the outgoing direction of the cable 14 (that is, the outgoing direction of the capstan) is corrected first, ensuring that the cable 14 after passing the radial guide wheel 41 coincides with the tangent direction of the end of the wire tube 15 in the radial direction of the capstan 16, so as to avoid the friction between the cable 14 and the outer wall of the end of the wire tube 15, which may cause wear of the cable or the wire tube, and the friction between the two may reduce the smoothness of the driver during normal use.

Referring to Figures 9 to 11, in some embodiments, since the pull wire 14 is wound in parallel on the capstan 16 (that is, when the pull wire is wound on the capstan one by one, it is wound in parallel from top to bottom or from bottom to top in accordance with the axial direction of the capstan, and when one layer is fully wound, the second layer is wound in the same manner), the winding position of the end of the pull wire 14 passing through the capstan 16 may not correspond to the end of the wire tube 15, and the winding position of the end of the pull wire 14 also changes along the axial direction of the capstan 16 during the process of the pull wire being pulled out or retracted, so that the pull wire 14 and the end of the wire tube 15 do not correspond, thereby causing friction between the pull wire and the outer wall of the end of the wire tube. Therefore, in order to ensure that the two correspond in the axial direction, by installing a capstan on the capstan A wire tube slider mechanism 46 which can reciprocate along the axial direction of the capstan 16 is arranged on the mounting seat 12 (specifically, a slider mounting seat 120 which cooperates with the wire tube slider mechanism 46 can be arranged on the capstan mounting seat 12), and the end of the wire tube 15 is fixed on the wire tube slider mechanism 46, and two axial guide wheels 42 are also arranged on the wire tube slider mechanism 46, as well as a slider rail 45 which is arranged on the capstan mounting seat and extends along the axial direction of the capstan, so that under the interaction force of the pull wire 14, the wire tube slider 46 is driven to reciprocate along the axial direction of the capstan on the slider rail 45 (or move up and down as shown in Figures 12 and 13) until the end of the wire tube 15 is tangent to the end winding position of the pull wire 14.

Referring to FIG. 11 , in some embodiments, the wire tube slider mechanism 46 includes a slider 461, a wire tube end mounting seat 462 disposed on one side of the slider 461, and two axial guide wheels 42 disposed on the other side. Specifically, the two axial guide wheels 42 are mounted on the axial guide wheel mounting seat 464 disposed on the other side of the slider 461 through a first cylindrical pin 463, so that the wire tube slider mechanism 46 is driven to move up and down under the interaction force between the cable 14 and the axial guide wheel 42 until the wire tube end is tangent to the winding position of the end of the cable. The axial guide wheel 42 can not only ensure that the wire tube slider mechanism 46 can slide smoothly on the slider rail 45, but also play a role in aligning the cable 14, further ensuring that the cable can smoothly enter the wire tube.

8 and 11, in order to bear the huge pressure of the wire tube end and distribute the pressure to the slider rail 45, the wire tube slider mechanism 46 also includes two groups of needle bearings 465 symmetrically installed in the mounting cavities 467 on both sides of the slider 461 through second cylindrical pins 466, wherein each group includes two needle bearings 465. Of course, in other embodiments, the number of needle bearings in each group can be adjusted according to actual needs.

Furthermore, the wire tube slider mechanism 46 also includes a slider end cover 47 for mounting the slider on the slider mounting seat 120 .

Of course, in other embodiments, the axial guide wheel may not be provided, and the wire tube slider may be directly slidably mounted on the slider rail. For example, a slide groove and a matching protrusion are respectively provided on the wire tube slider and the slider rail.

Referring to Fig. 17, which is a cross-sectional view of the pawl when it is installed in reverse, the winding direction of the cable 14 and the outlet direction of the cable tube 15 need to be adjusted accordingly. At this time, the motor 11 will lock the pawl 132 when it rotates counterclockwise, and provide assistance to the winch 16.

Referring to Figure 16, in some other embodiments, elastic friction may be used instead of magnetic friction. Specifically, it includes the above-mentioned components, except that there is no need to provide a corresponding pawl magnet on the pawl 132, but an elastic friction component is provided on the first side (corresponding to the side of the friction surface) of the pawl 132 corresponding to the iron sheet 31 (i.e., the first friction component providing the friction surface).

When the driving device does not provide driving force, under the action of the friction force between the elastic friction component and the first friction component, the locking component releases the locked component, so that the driving device and the winch are unlocked in both directions; when the driving device provides driving force and drives the locking component to rotate, the locking component drives the elastic friction component to rotate relative to the friction component, so that under the action of the friction force generated between the elastic friction component and the friction component, the locking component quickly unidirectionally locks the locked component, thereby unidirectionally locking the driving device and the winch.

In some embodiments, the elastic friction assembly includes: an elastic reset member, one end of which is fixed to the first side of the pawl, and the other end of which is fixedly connected to a friction block 135 that can slide on the friction surface of the iron sheet 31. Of course, the first friction component may not use an iron sheet, but other components that can provide a friction surface for the friction block.

In some embodiments, the elastic reset member is a spring 136, one end of which is fixed in a friction block mounting hole 1320 opened on the first side of the pawl, and the other end is fixed on the friction block 135. In the initial state, the spring is in a compressed state, so that when its elastic force acts on the friction block 135, the friction block is only pressed on the iron sheet 31.

Of course, in other embodiments, the second friction component may not adopt a friction block connected to the pawl through an elastic reset member, but can be directly implemented by a friction block made of elastic material. It only needs that the friction block can apply a certain pressure to the first friction component in a direction perpendicular to the friction surface.

When the motor 11 rotates or provides assistance, the output disk of the motor drives the pawl to rotate, and accordingly, the friction block rotates with the pawl. At this time, friction is generated between the friction block and the iron sheet due to pressure, so that the pawl and the ratchet wheel are quickly engaged.

In some embodiments, in order to facilitate recording the number of recovery rotations, the driver further includes: a radial magnet 187 mounted on the end of the slotted shaft 162 of the capstan 16, and an angle sensor for detecting the recovery rotation angle, which is disposed on the coil spring cover 185. Preferably, the angle sensor is a magnetic angle meter 186.

The present invention also provides an exoskeleton with automatic cable recovery, comprising a cable 14 and the above-mentioned driving device.

The above are only preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be based on the scope defined by the claims. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims (10)

1. A friction damping driver, comprising a winch and a driving device for driving the winch to rotate, wherein a force transmission component for transmitting power assistance is wound on the winch; the method is characterized in that: the winch further comprises a locked part arranged on the winch, a locking part and a first friction part which are arranged at the output end of the driving device, and a second friction part which is arranged on the locking part and can interact with the first friction part to generate friction force;

when the driving device does not provide driving force and reversely rotates relative to the winch, the second friction part is driven to rotate relative to the first friction part, so that the locked part is released by the locking part under the action of friction force between the first friction part and the second friction part, and the driving device and the winch are unlocked bidirectionally;

when the driving device provides driving force and drives the locking part to rotate forward, the locking part locks the locked part in one direction rapidly under the action of friction force generated between the second friction part and the first friction part, so that the driving device and the winch are locked in one direction.

2. The friction damped drive of claim 1, wherein said first friction member and said second friction member are magnetically attractable elements; or alternatively

The second friction part is a magnetic element with magnetic force, and the first friction part is a polar element which can be attracted by the magnetic force of the magnetic element; or alternatively

The first friction part is used for providing a friction surface, and the second friction part is a friction block which is connected to the locking part through an elastic resetting piece and can slide relative to the first friction part to generate friction force.

3. The friction damped drive of claim 1, wherein said locked component is a ratchet wheel, said locking component is a pawl, and the tooth form of said pawl and the tooth form of said ratchet wheel are both rotationally symmetric.

4. The friction damped drive of claim 1, further comprising: an introduction mechanism for introducing the force transmission member into a conduit, the introduction mechanism comprising: the first correction component is arranged on the inlet side of the spool and is used for radially correcting the outlet direction of the force transmission component so that the force transmission component coincides with the tangential direction of the spool end in the radial direction of the winch; and/or the number of the groups of groups,

And the second correction assembly is arranged on the inlet side of the spool and is used for axially correcting the outlet direction of the force transmission component or axially correcting the spool end, so that the spool end is tangential to the tail end winding position of the force transmission component.

5. The friction damped drive of claim 4, wherein said first correction assembly includes at least one radial guide wheel mounted on a capstan mount.

6. The friction damped drive of claim 4, wherein said second correction assembly comprises at least two axial guide wheels mounted on a capstan mount, or said second correction assembly comprises: an axial slide rail providing an axial movement path for the spool, at least two axial guide wheels movable on the axial slide rail along the axial movement path.

7. The friction damped drive of claim 6, wherein said second correction assembly further comprises: and the axial needle bearings are used for bearing the pressure of the end head of the spool and dispersing the pressure to the axial sliding rail.

8. A friction damped driver according to claim 1 further comprising a resilient energy storage mechanism connected in parallel with said drive means at a force input of said force transmitting member, said resilient energy storage mechanism storing force when the wire is pulled out and releasing resilient potential energy when the drive means ceases to provide drive force to drive the capstan to retract the wire.

9. A friction damped drive according to claim 1, wherein: the driving device is a motor; and/or the force transmission component is one of a metal wire, a rope and a braid.

10. A power assisting exoskeleton, which is characterized in that: comprising a friction damped drive according to claims 1-9.