KR102168226B1 - Elastomer Gear Unit And Elastic Actuator Having The Same - Google Patents

Abstract

The present invention is made of a metal material, but is inserted into an inner gear of an elastic gear having torsional elasticity for its own rotation torque and a ring-shaped external gear connected to the motor by forming a plurality of arc-shaped slits. Noise and vibration are reduced, the durability is improved compared to the case of inserting a non-metallic elastic member, and higher elasticity than a metal-only gear can be secured, and the structure of the joint actuator can be constructed as a single gear. It relates to an elastic gear unit that can be simplified and a joint actuator having the same.

Description

Elastomer Gear Unit And Elastic Actuator Having The Same}

The present invention relates to an elastic gear unit and a joint actuator having the same. In more detail, the present invention is made of a metal material, but is inserted into a ring-shaped outer gear connected to the motor and the inner gear of the elastic gear having torsional elasticity for its own rotation torque by forming a plurality of arc-shaped slits. , Noise and vibration when driving the motor are reduced, durability is improved compared to the case of inserting a member made of non-metallic elastic material, and higher elasticity can be secured than a gear made of metal only, and it can be configured in a single gear shape. It relates to an elastic gear unit capable of simplifying the structure of the actuator and a joint actuator having the same.

Recently, the development of wearable robots for the disabled, patients, or the elderly who have physical abilities that are impossible to daily life, or industrial or military wearable robots to reinforce physical strength or physical abilities are in progress.

In the case of wearable robots for the handicapped, patients, or the elderly, it can be classified into wearable robots for completely paralyzed persons with disabilities and wearable robots for the elderly or partially paralyzed patients or handicapped according to their physical ability and required assistive power .

In the former case, since the user has no physical ability, the motion intention for the movement of the user's lower limbs is not of great significance as a control variable of the robot, so the wearable robot can walk accurately instead of the user's lower limb movement with sufficient force. You can do it.

Therefore, in the case of the former wearable robot, the required driving force is large and accordingly, the driving device, the battery, and the skeleton structure are large in many cases.

However, in the case of the latter wearable robot, the size and weight of the wearable robot are minimized, and the key is to provide accurate assistance according to the user's motion intention. I can.

In the case of the latter wearable robot, if the robot wearer's movement is possible to a certain extent, if the weight of the robot or the mechanical resistance of the joint drive device is large, the wearer may feel quite cramped and uncomfortable. A structured wearable robot is required. Furthermore, in recent years, in the case of providing assistance from a robot that is different from the user's movement or intention, it may cause discomfort or injury to the user, and while allowing the user's movement, it is intended to accurately provide assistance by grasping the user's motion intention. Research is ongoing.

In addition, when the joint actuator is applied to a wearable robot for patients with partial paralysis of the lower body or for the elderly, it requires a technology to minimize the weight or volume of the robot while increasing the operating time of the wearable robot so that it can be used in daily life. do.

To this end, in order to minimize the weight and volume of the joint actuator for providing the assisting force of each joint, the structure of the driving device, which is the main component of the wearable robot, should be simplified, and lightweight and compact should be premised.

In addition, when a joint driving device made of a metal material is driven, noise and vibration may be large, and minimizing the noise and vibration of the joint driving device is expected to be helpful in the spread and use of the wearable robot.

In particular, since these wearable robots are applicable not only to adult patients or persons with disabilities, but also to pediatric patients or disabled persons with weak muscle strength, mechanical resistance is reduced, the structure is simplified to reduce weight, and noise and vibration are minimized to minimize rejection to the robot. There is a greater demand for a driving device capable of grasping the robot wearer's motion intention.

The present invention is made of a metal material, but is inserted into an inner gear of an elastic gear having torsional elasticity for its own rotation torque and a ring-shaped external gear connected to the motor by forming a plurality of arc-shaped slits. Noise and vibration are reduced, the durability is improved compared to the case of inserting a non-metallic elastic member, and higher elasticity than a metal-only gear can be secured, and the structure of the joint actuator can be constructed as a single gear. It is an object to be solved to provide an elastic gear unit that can be simplified and a joint actuator having the same.

In order to solve the above problems, the present invention is composed of a metal material, a shaft hole is formed in the center of the shaft hole, the inner gear in which at least one slit in the form of an arc for elastic deformation is formed around the shaft hole, a non-metal material surrounding the outer shell of the inner gear Of the elastic member, the outer gear surrounding the outside of the elastic member and having a plurality of gear teeth formed on an outer circumferential surface thereof, wherein the outer gear or the inner gear transmits a driving force to the inner gear or the outer gear through the elastic member. It is possible to provide an elastic gear unit characterized by.

In this case, when the outer gear is rotationally driven, the inner gear is elastically deformed to change the shape of the slit of the inner gear by the driving force transmitted by the elastic member, and then rotated in the direction in which the elastic deformation is removed. I can.

In addition, when the rotational shaft mounted in the shaft hole of the internal gear is rotationally driven, the internal gear is elastically deformed to change the shape of the slit of the internal gear and then rotationally driven in the direction in which the elastic deformation is removed, and the internal gear is elastically deformed. The driving force may be transmitted to the external gear through a member.

Here, the slit formed in the inner gear may have a shape in which curvatures at one end and the other end are gradually changed, respectively, and may be provided at a position symmetrical around the shaft hole.

Further, at least one locking protrusion is formed on one side of the outer circumferential surface of the inner gear and the inner circumferential surface of the elastic member, and a locking groove in which the locking protrusion is seated is formed on the other side, so that the driving force can be transmitted in both directions.

In addition, in order to solve the above problems, the present invention is a joint actuator provided in a wearable robot, a motor, a motor gear mounted on a rotating shaft of the motor, the elastic gear unit directly or indirectly connected to the motor gear, A drive gear mounted on the rotation shaft of the elastic gear unit, a joint gear directly or indirectly geared to the motor gear, a joint gear connected to the joint gear and rotationally driven by the driving force provided by the joint gear, or the movement of the robot wearer's joint It may include an output member that is rotationally driven corresponding to and an encoder provided on the motor and the joint gear to detect a rotation direction, a rotation angle, or a rotation speed of the motor and the joint gear.

In addition, the joint actuator is mounted on a hip joint or a knee joint of a robot wearer, and an output member constituting the joint actuator may be fastened to a thigh member or a lower leg member, respectively.

Here, when the motor of the joint actuator is driven, the driving force of the motor is transmitted to the output member through the elastic gear unit and the joint gear, and when the wearer walks, the output member of each joint actuator is each femoral member or It is possible to assist the wearer's walking by rotating the lower leg member.

In addition, when the motor constituting the joint actuator is stopped and the output member constituting the joint actuator rotates and the rotation of the joint gear is detected by an encoder provided in the joint gear, the motor The motor may be driven in the direction of rotation.

According to the elastic gear unit and the joint actuator having the same according to the present invention, an elastic member made of a non-metal material is additionally provided between the inner gear in the form of an elastic gear made of metal and the external gear, thereby maximizing the effect of reducing noise and vibration.

In addition, according to the elastic gear unit and the joint actuator having the same according to the present invention, durability is improved than when a member made of a non-metallic elastic material is inserted into the joint actuator, and higher elasticity than a gear made of metal can be secured.

In addition, according to the elastic gear unit and the joint actuator having the same according to the present invention, in order to impart elasticity to the gear, it is not a bulky gear assembly or a gear assembly, but in the form of a disk-shaped single spur gear that does not have a protruding part to the outside. Configuration is possible.

In addition, according to the elastic gear unit and the joint actuator having the same according to the present invention, it is applied to a wearable robot applied to a pediatric patient or a disabled person with weak muscle strength, reducing mechanical resistance, simplifying the structure to reduce weight, and noise By minimizing over-vibration, it is possible to minimize rejection to the robot.

1 is a side perspective view of a wearable robot to which a joint actuator using an elastic gear unit of the present invention can be applied.
2 is a front view of the wearable robot shown in FIG. 1.
3 shows an example of a joint actuator according to the present invention.
Figure 4 shows a perspective view of the elastic gear unit according to the present invention
5 shows an exploded view of the elastic gear unit according to the present invention.
6 is a radial cross-sectional view of the cover of the elastic gear unit according to the present invention.
7 to 9 show examples of a deformation process inside the elastic gear unit in a process in which the driving force is transmitted through the elastic gear unit when the driving motor is driven.
10 and 11 show examples of a process of deforming the inside of the elastic gear unit and a process of assisting driving force by the drive motor when the output member is rotated by the movement of the robot wearer while the drive motor is stopped.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed contents may be thorough and complete, and the spirit of the invention may be sufficiently conveyed to those skilled in the art. Throughout the specification, the same reference numbers indicate the same elements.

1 is a side perspective view of a wearable robot 1000 to which a joint actuator using an elastic gear unit 10 of the present invention can be applied, and FIG. 2 is a front view of the wearable robot 1000 shown in FIG. 1.

Referring to FIGS. 1 and 2, in the present specification, the wearable robot 1000 may be a robot that assists walking motion by being worn on the lower body of a disabled person, an elderly person, or a patient (hereinafter, referred to as “wearer”). Here, the meaning of assisting the gait motion means providing a driving force for preserving insufficient muscle strength in the hip and knee joints to enable independent walking of the wearer with some of the lower body's motor functions.

The wearable robot 1000 includes a body 500 disposed at the waist of the wearer, and a pair of leg units 600l and 600r extending downward from the body 500 to support each leg of the wearer. Can include.

Here, the leg units 600l and 600r are provided at the hip joint and the knee joint, respectively, and provide auxiliary torque to the thigh and lower leg to assist the wearer's independent walking.

Accordingly, a driving device for providing a driving torque may be provided in a region corresponding to a hip joint and a knee joint of each of the leg units 600l and 600r. Each driving device may be composed of a joint actuator 100 that outputs a driving force through an elastic member 3 or the like.

Each leg unit is connected to the joint actuators (100a, 100b), and the joint actuators (100a, 100b), respectively, to support or assist the wearer's thigh and lower thigh member and lower leg member (410, 430) and lower leg member 430 ) And may be provided with a foot support portion 300 for supporting the wearer's foot.

The joint actuators (100a, 100b) may be installed at the hip and knee joints of the wearer, respectively, the first joint actuator (100a) is installed at the site where the pelvis and the thigh meet, and the second joint actuator (100a) is installed at the knee area at the boundary between the thigh and lower leg. Joint actuator (100b) may be installed. In the wearable robot shown in FIGS. 1 and 2, an example in which a joint actuator is provided only in the hip and knee joints of the wearer is illustrated, but a separate driving device may be provided for the ankle joint as needed.

And, each of the femoral member and the lower leg member (410, 430) may be provided with a wearing portion 420 in the form of a band for fixing the wearer's thigh and lower leg to the femoral member and the lower leg member (410, 430), , The driving force provided by each joint actuator may eventually be transmitted to the wearer's thigh or lower leg through the wearing part 420 to assist independent walking.

In order for the joint actuator to generate an accurate assisting force, it is necessary to measure the user's muscle strength according to the situation, and in general, in order to accurately measure the user's muscle strength, etc., sensors used in wearable robots are expensive, bulky, and sensors. Since the signal is very sensitive to noise, it is difficult to use it practically in a mobile environment such as a wearable robot. Accordingly, the present invention determines the user's motion intention by applying the elastic gear unit, and drives the motor in a direction to remove the amount of deformation of the elastic gear, etc., thereby minimizing the mechanical resistance felt by the user, and determining the motion intention. It can provide auxiliary driving force according to.

Hereinafter, the joint actuator 100 according to the present invention used in the wearable robot 1000 and the wearable robot according to the present invention applicable to the joint actuator 100 will be described in detail. In the embodiment shown in Figs. 1 and 2, the joint actuators installed in the hip joint and the knee joint may have different driving times or the magnitude of the driving force, respectively, but the joint actuators described below are respectively located in the hip joint or the knee joint region. It should be understood as a drive that can be mounted.

3 shows an example of a joint actuator 100 according to the present invention. The joint actuator 100 shown in FIG. 3 is shown with the outer housing removed for convenience of illustration.

An example of the joint actuator shown in FIG. 3 is fixed to the output member 30, the second encoder 45, and the output member 30 from the bottom to rotate the output member 30, or the output member ( The joint gear 40 that rotates together when 30) is rotated, the driving gear 13 connected to the joint gear 40, and the elastic gear unit 10 axially coupled to the driving gear 13 by the same rotation shaft 11 , It may be configured to include a motor gear 23 connected to the elastic gear unit 10 and axially coupled to the motor shaft 21 and a drive motor 20 for driving the motor shaft 21.

When the drive motor 20 is driven by the control unit (not shown) of the wearable robot, the torque generated by the drive motor 20 is sequentially converted to the motor rotation shaft 21, the motor gear 23, and the elastic gear unit 10. ), the drive gear 13, the joint gear 40, and the like, to the output member 30 to assist the movement of the thigh or lower leg. The output member 30 may be fastened to the femoral and lower thigh members 410 and 430 of the wearable robot shown in FIGS. 1 and 2, and further may be integrally configured.

Meanwhile, when the wearer wears the above-described wearable robot 1000 and performs active movement, the movement may be transmitted to the elastic gear unit 10 through the output member 30 connected to the joint gear 40. have.

Among the wearable robots for walking assistance, a robot for a completely paralyzed patient cannot move a wearer whose lower body is completely paralyzed, so there is a low need to determine the motion intention of the wearer. As a wearable robot for patients with some remaining lower body functions, if the user's movement or intent is provided with the assistance of a different robot, it may cause discomfort or injury to the user. Since it is necessary to accurately provide assistive power by grasping the motion intention, the elastic gear unit 10 of the present invention may be applied to the joint actuator 100 to accurately determine the motion intention of the user.

First, in a state in which the driving motor 20 is stopped, the output member 30 may be rotated according to the movement of the wearer, and the joint gear 40 mounted on the output member 30 is an elastic gear unit 10 The center of the can be rotated.

In this case, when the driving motor 20 is not driven, the control unit of the joint actuator causes torsional deformation of the internal gear 2 (see FIG. 4) and the elastic member 3 to be described later inside the elastic gear unit 10. When the amount of deformation is detected by the second encoder 45 provided in the joint gear 40, it is determined that there is an intention to operate in that direction, and the internal gear 2 and the elastic member 3 are The motion intention for the joint is determined so that the torsional deformation is eliminated, and the assisting force is provided in the deformation direction, so that the wearer can move in a state in which the mechanical resistance provided by the joint actuator is minimized.

That is, when the wearer of the wearable robot 1000 wants to move to some extent according to his or her own operation intention, even if the driving motor 20 is not driven, the output member 30 first rotates within a predetermined allowable range. In this case, the rotation of the output member 30 may deform the elastic gear unit 10, and the rotation of the output member 30 may be a second encoder 45 that may be mounted on the joint gear 40 side. ), the rotation angle or direction of rotation is detected, and can be used as data to determine the user's intention to operate.

Therefore, the control unit (not shown) provided in the body of the wearable robot 1000 is based on the collected data, regardless of whether the driving motor 20 is driven or not, the rotation angle or the rotation direction of the output member 30 When the amount of change is detected, it may be determined that there is an intention of the user to operate in the corresponding change direction.

In a robot that drives a joint, etc. using a drive motor and a reduction gear (not shown), if the wearer's movement occurs regardless of the drive of the motor, the wearer feels a considerable amount of mechanical resistance or Although it may not be possible to move, the elastic gear unit 10 is mounted between the output member 30 and the driving motor 20, thereby reducing mechanical resistance against the user's movement.

After all, when the elastic gear unit 10 is mounted, the mechanical resistance to the user's movement is reduced, and the rotation angle and direction of rotation through encoders that may be respectively provided on the output member 30 and the driving motor 20 side. Alternatively, it is possible to collect information such as rotational speed and collect control signals to analyze the user's motion intention, which enables low resistance-walking.

Specifically, the rotation angle and rotation direction of the drive motor 20 in a direction in which the amount of deformation of the elastic gear unit 10 is removed by using information such as rotation angle, rotation direction, or rotation speed collected by each encoder, etc. Alternatively, when the rotational speed is controlled, the driving force of the driving motor 20 may be provided according to the user's intention or movement, and such an effect enables a low resistance operation.

In the low-resistance walking mode, the wearer is able to move while being provided with additional assisting force according to the motion intention in a state where the weight or mechanical friction of the wearable robot is substantially reduced or not.

That is, in the case of a wearer capable of performing his or her own motion to some extent, it may be possible to move in the low-resistance walking mode with the feeling that the robot is not worn.

In addition, even when the elastic gear unit 10 of the present invention is applied, the range of the axial torsion of the elastic gear unit 10 is allowed within a limited range, as described later, so that the driving motor 20 is each It can provide the required assistance to the joints.

Figure 4 shows a perspective view of the elastic gear unit 10 according to the present invention, Figure 5 shows an exploded view of the elastic gear unit 10, Figure 6 is except for the upper cover 110 and the lower cover 150 The front view of the elastic gear unit 10 is shown.

As shown in FIGS. 4 to 6, the elastic gear unit 10 includes an outer gear 4 in a ring shape, and may include an elastic member 3 and an inner gear 2 in the inner direction. .

The elastic member 3 may be configured in a ring shape, and an inner gear 2 may be mounted on an inner circumferential surface thereof, and an outer gear 4 in a ring shape may be mounted on an outer circumferential surface thereof.

Specifically, the present invention is composed of a metal material, a shaft hole (2h) is formed in the center of the shaft hole (2h) at least one inner gear formed with an arc-shaped slit for elastic deformation (2); An elastic member 3 made of a non-metal material surrounding the outer side of the inner gear 2; The elastic member (3) includes an outer gear (4) that surrounds the outside and has a plurality of gear teeth formed on the outer circumferential surface, the outer gear (4) or the inner gear (2) is the inner through the elastic member (3) It is possible to provide an elastic gear unit 10 that transmits a driving force to the gear 2 or the external gear 4.

And, as shown in Figure 5, the elastic gear unit 10 according to the present invention has a first cover (1) and a second cover (5) on one side and the other side, the internal gear (2) and The elastic member (3) prevents the separation of the double elastic gears, reduces noise that may be generated when driving the inner gear (2), the elastic member (3) and the outer gear (4), and prevents pinching or interference with external foreign substances. I can.

Therefore, the inner gear 2, the elastic member 3, and the outer gear 4 are each configured in a ring shape to enable sequential assembly, but in the assembled state, a general disk-shaped spur gear as shown in FIG. It can be configured in the shape of.

5 and 6, the inner gear 2 has a shaft hole 2h in which the rotation shaft 11 shown in FIG. 1 is mounted at the center thereof, and a driving gear mounted on the rotation shaft 11 (13) transmits the driving force of the motor to the joint gear 40 through the rotation shaft or transmits the rotation torque to the elastic gear unit 10 when the output member 30 rotates by the movement of the robot wearer to the elastic gear unit 10 ), or the elastic gear unit 10 may be rotated accordingly.

The shaft hole may be formed in a polygonal shape, for example, a hexagonal shape, as shown in FIG. 4 in order to prevent slip of the rotation shaft 11.

5 and 6, the internal gear 2 may be made of a material such as metal, and may have a structure in which a plurality of slits 2s are provided in the circumferential direction to generate elasticity when an external force or torque is applied. have.

The internal gear 2 may be provided with a plurality of slits to have torsional elasticity when a rotation torque is provided. As shown in FIGS. 5 and 6, the slit is configured in an arc shape, and may be configured in a shape in which the curvature at one end and the other end is gradually changed, and a plurality of such slits 2s are provided. As shown in FIG. 6, the slit 2s may be provided at a symmetrical position around the shaft hole 2h so that uniform twisting of the internal gear 2 as a whole may occur when torque is applied.

And, as described above, at least one locking protrusion may be formed on one side of the outer circumferential surface of the inner gear 2 and the inner circumferential surface of the elastic member 3, and a locking groove in which the locking protrusion is seated may be formed on the other side, and the elasticity At least one locking protrusion is formed on one side of the outer circumferential surface of the member 3 and the inner circumferential surface of the outer gear 4 and a locking groove in which the locking protrusion is seated is formed on the other side, so that the driving force can be transmitted in both directions.

5 and 6, locking protrusions 2p and 4p are formed on the outer circumferential surface of the inner gear 2 and the inner circumferential surface of the outer gear 4, and on the inner and outer circumferential surfaces of the elastic member 3 A locking groove 3g in which the locking projections 2p and 4p are respectively seated may be formed on the outer circumferential surface of the inner gear 2 and the inner circumferential surface of the outer gear 4.

If the locking protrusion is not formed on the inner gear 2 and the external gear 4 made of metal, but is formed on the elastic member 3 made of a resin material such as non-metallic material, rubber or urethane, the durability of the protruding protrusion may be a problem. Therefore, the locking protrusion may be formed on the outer and inner circumferential surfaces of the inner gear 2 and the outer gear 4, respectively.

However, the positions of the locking protrusion and the locking groove may be changed depending on the material of the elastic member 3 and the amount of torque applied from the outside. In addition to rubber or urethane, the elastic member 3 may be formed of various materials as long as it has sufficient elasticity and durability.

As described above, since the inner gear 2 has a slit formed to have torsional elasticity, it can act like an elastic member against an external force, but an elastic member made of resin material than when only the inner gear 2 made of metal is used. If (3) is added, the elastic deformation range can be increased, and smooth operation feeling and noise reduction effect can also be obtained.

In particular, in the case of children's wearable robots with insufficient muscle strength, even if the joint actuator is designed with a structure that allows the understanding of the motion intention, when the configuration providing elasticity is made of only metal, when the minimum muscle strength to deform it is insufficient or sufficient elasticity It has been confirmed that if the deformation range is not provided, it may be useless, and if an elastic gear made of a metal material that is allowed to rotate even with a small force is designed, it is easily damaged and it is difficult to secure sufficient durability.

In addition, when the joint actuator is made of only metal, considerable noise and vibration are generated, which increases the feeling of rejection of the wearable robot.

That is, by interposing the elastic member 3 between the inner gear and the outer gear, there is an advantage of providing a sufficient elastic deformation range for the general movement of the wearer, reducing noise and vibration, and providing durability of the joint actuator. .

7 to 9 show examples of a deformation process inside the elastic gear unit 10 in a process in which the driving force is transmitted through the elastic gear unit 10 when the driving motor is driven.

The state in which no external force is applied and the elastic gear unit 10 is not deformed is assumed to be the state of FIG. 6.

First, as shown in FIG. 7, when the driving motor is driven and torque T is applied to the external gear 4 so that the external gear 4 is first rotated counterclockwise by a predetermined angle θ, the external The elastic member 3 mounted inside the gear 4 is elastically deformed.

Therefore, the deformed elastic member 3 rotates the outer region of the inner gear 2 by pushing the locking protrusion 2p of the inner gear 2 through restoration elasticity, as shown in FIG. The shape of the slot 2s of the gear 2 is changed.

In this case, as shown in Figs. 8 and 9, the inner gear 2 in which the deformation of the slot 2s is generated is provided in the direction to remove the deformation of the slot 2s, that is, the external gear ( In the same direction as the direction of rotation of 4), a driving torque is applied to the inner region provided with the shaft hole of the inner gear 2, and the rotation shaft 11 connected to the shaft hole of the inner gear 2 and the rotation shaft 11 are connected. By rotating the joint gear 40 and the output member 30, it is possible to provide the assisting force required to each joint of the robot wearer according to the walking cycle.

In this way, even when the driving motor is driven to provide an auxiliary force, the internal gear and the elastic member are momentarily deformed and restored, and noise and vibration are minimized, and a stable driving force can be provided.

Accordingly, the state shown in FIG. 9 is similar to the state shown in FIG. 6, in a state in which the internal gear 2 and the elastic member 3 are deformed or twisted, and the elastic gear unit 10 as a whole is at a predetermined angle ( θ) It may be in a rotated state.

7 to 9 show that the elastic member 3 and the internal gear 2 are transformed and restored in a short time while the driving motor is operated to actively provide the assisting force to transmit the driving torque. The two-stage elastic structure of the elastic member 3 and the inner gear 2 reduces noise and vibration and provides a smooth operation feeling, and furthermore, the durability and the elastic member 3 of the metal inner gear 2 It can have both the advantages of elasticity or elastic displacement.

In addition, the deformation and restoration of the internal gears shown in FIGS. 7 to 9 can be performed in a very short time, and the internal gears shown in FIGS. 7 to 9 and the internal gears shown in FIGS. Deformation and restoration of the elastic member may be repeated.

That is, the elastic gear unit 10 constituting the joint actuator according to the present invention, when the outer gear 4 is driven to rotate, the inner gear 2 is driven by the driving force transmitted by the elastic member 3 After being elastically deformed to change the shape of the slit of the internal gear 2, it is rotated in a direction in which the elastic deformation is removed, thereby providing an auxiliary force.

When the driving of the elastic gear unit 10 is reviewed from the side of the joint actuator, when the driving motor 20 of the joint actuator 100 (see FIG. 1) is driven, the driving force of the driving motor is the elastic gear unit 10 ) And the joint gear 40 through the output member 30, and when the wearer walks, the output member 30 of each joint actuator rotates each femoral member or lower leg member to drive the wearer's It can assist with the movement of the thigh and lower leg.

10 and 11 show examples of the deformation process inside the elastic gear unit 10 and the process of assisting the driving force by the driving motor when the output member 30 is rotated by the movement of the robot wearer while the driving motor is stopped. do.

As described above, the elastic gear unit 10 or a joint actuator having the same according to the present invention includes an elastic gear-shaped inner gear 2 and an elastic member 3 made of a non-metallic material having elasticity, so that the driving motor It is possible to move the femoral member or the lower leg member, respectively, even in the state where the is stopped.

When a rotation torque is applied to the rotation shaft mounted in the shaft hole of the inner gear 2 constituting the elastic gear unit 10 of the present invention, the inner gear 2 changes the shape of the slit of the inner gear, and the elastic member (3) is elastically deformed by the driving force transmitted by the internal gear, so that the rotation of the rotation shaft can be allowed within a predetermined range even when the external gear is stopped.

That is, in a state in which the driving motor 20 is stopped, the output member 30 may be rotated according to the movement of the wearer, and the joint gear 40 (see FIG. 3) mounted on the output member 30 is an elastic gear The central portion of the unit 10, that is, the shaft hole area can be rotated.

In addition, such a movement may be detected by the second encoder 45 (refer to FIG. 3) provided in the joint gear 40 or the like.

That is, as shown in FIG. 9, when the output member 30 connected to the femoral member or the lower leg member is rotated, the joint gear 40 rotates together, and the second encoder rotates the joint gear 40 Can be detected. In addition, as the drive gear connected to the joint gear 40 rotates, the rotation shaft of the drive gear rotates, and the rotation shaft mounted in the shaft hole of the inner gear 2 rotates at a predetermined angle (θ') counterclockwise Then, the inner gear 2 is elastically deformed so that the shape of the slit 4s of the inner gear 2 is changed.

When the movement of the joint is detected by the second encoder 45, the controller of the wearable robot determines that the doctor of the robot wearer has an intention to move the joint, and detects the joint as shown in FIG. The driving motor is driven in the direction of movement to provide additional driving torque T'to the external gear 4.

The external gear 4 is rotated in the direction of movement of the joint by the driving torque T', the deformation state of the elastic member 3 and the internal gear 2 is removed, and the joint is moved in the direction in which the joint is intended to move. Assistance can be started.

The state shown in FIG. 10 shows a state in which the internal gear 2 and the elastic gear are momentarily distorted from the inside of the external gear 4 by driving the driving motor. However, when the driving motor continues, FIGS. 7 to 7 The driving torque of the driving motor is transmitted to the output member 30 in a manner as shown in FIG. 9 to provide an auxiliary force.

As described above, the present invention includes an elastic gear unit 10 that allows torsional deformation, allows a certain degree of movement of the joint even when the driving motor is not driven, and when the movement of the joint is detected by an encoder or the like, By driving the driving motor in the direction of movement of the joint, it is possible to minimize mechanical resistance or heaviness felt by the wearer of the robot, and provide intelligent assistance.

Although the present specification has been described with reference to preferred embodiments of the present invention, those skilled in the art will variously modify and change the present invention within the scope not departing from the spirit and scope of the present invention described in the claims described below. You will be able to do it. Therefore, if the modified implementation basically includes the elements of the claims of the present invention, all should be considered to be included in the technical scope of the present invention.

10: elastic gear unit
20: drive motor
30: output member
40: drive gear
100: joint actuator

Claims (11)

An internal gear made of a metal material, having a shaft hole formed in a center thereof, and having at least one arc-shaped slit for elastic deformation around the shaft hole;
An elastic member made of a non-metallic material surrounding the outside of the inner gear; And,
It includes an external gear surrounding the outside of the elastic member and having a plurality of gear teeth formed on the outer circumferential surface thereof,
The elastic gear unit, characterized in that the external gear or the internal gear transmits a driving force to the internal gear or the external gear via the elastic member. The method of claim 1,
When the external gear is driven to rotate,
The internal gear is elastically deformed so that the shape of the slit of the internal gear is changed by the driving force transmitted by the elastic member, and then the shaft hole region is rotated in a direction in which the elastic deformation is removed. The method of claim 1,
When a rotation torque is applied to the rotation shaft mounted in the shaft hole of the inner gear,
The inner gear changes the shape of the slit of the inner gear, and the elastic member is elastically deformed by the driving force transmitted by the inner gear, so that the rotation of the rotation shaft is allowed within a predetermined range even when the outer gear is stopped. An elastic gear unit, characterized in that. The method of claim 1,
The elastic gear unit, characterized in that the slit formed in the inner gear has a shape in which curvatures at one end and the other end are gradually changed, respectively. The method of claim 4,
The elastic gear unit, characterized in that the slit formed in the inner gear is provided at a position symmetrical about the shaft hole. The method of claim 1,
An elastic gear unit, characterized in that at least one locking protrusion is formed on one side of the outer circumferential surface of the inner gear and the inner circumferential surface of the elastic member, and a locking groove in which the locking protrusion is seated is formed on the other side to transmit driving force in both directions. The method of claim 1,
An elastic gear unit, characterized in that at least one locking protrusion is formed on one side of the outer circumferential surface of the elastic member and the inner circumferential surface of the outer gear, and a locking groove in which the locking protrusion is seated is formed on the other side to transmit driving force in both directions. In the joint actuator provided in the wearable robot,
motor;
A motor gear mounted on the rotating shaft of the motor;
An elastic gear unit according to any one of claims 1 to 7 geared directly or indirectly to the motor gear;
A driving gear mounted on the rotation shaft of the elastic gear unit;
A joint gear connected directly or indirectly to the drive gear;
An output member connected to the joint gear and rotated by a driving force provided by the joint gear, or rotated in response to a movement of a robot wearer; And,
An encoder provided on the motor and the joint gear to detect a rotation direction, a rotation angle, or a rotation speed of the motor and the joint gear. The method of claim 8,
The joint actuator is mounted on a hip joint or a knee joint of a robot wearer, and an output member constituting the joint actuator is coupled to a femoral member or a lower leg member, respectively. The method of claim 9,
When the motor of the joint actuator is driven, the driving force of the motor is transmitted to the output member through the elastic gear unit and the joint gear, and when the wearer is walking, the output member of each joint actuator is Joint actuator, characterized in that to assist the wearer's walking by assisting the rotation drive. The method of claim 9,
When the motor constituting the joint actuator is stopped and the output member constituting the joint actuator rotates and the rotation of the joint gear is sensed by the encoder provided in the joint gear, the motor is the rotation direction of the joint gear. Joint actuator, characterized in that it is driven to provide an auxiliary force.

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