JP6500429B2 - Rigidity control method - Google Patents

Description

The present invention relates to a stiffness control method that makes the stiffness of a rocking joint device performing periodic rocking motion variable.

  As an example of a device that controls a joint that performs periodic rocking motion, for example, Patent Document 1 discloses a walking assistance device that provides an assisting force to a user's lower leg (from the hip joint to the toes). The walking assistance device includes a lumbar orthosis mounted so as to wind the user's lumbar, a connecting bar extending from the side of the hip joint to the side of the knee joint, and a lower part extending from the side of the knee joint to the calf. It has a thigh brace, a hip joint actuator attached to a lateral position of a hip joint in a connecting bar, and a knee joint actuator attached to a lateral position of a knee joint in the connecting bar. The hip joint actuator is then attached to the joint of the lower back orthosis, and swings the connecting bar back and forth around the hip joint relative to the lower back hip joint on the side of the hip joint. In addition, the knee joint actuator swings the lower leg orthosis back and forth around the knee joint with respect to the connection bar on the side of the knee joint. In addition, the hip joint actuator and the knee joint actuator are electric motors, and the electric power to the electric motors is supplied from a battery attached to the lumbar brace.

  In addition, Patent Literature 2 discloses a walking rehabilitation apparatus that supports rocking movement of a user's lower thigh (from knee to ankle). The walking rehabilitation apparatus includes a controller disposed around the user's waist, a thigh link extending from the side of the hip joint to the side of the knee joint, and a lower leg link extending from each of the two sides of the knee joint to the ankle joint. A motor disposed laterally of the knee joint, and a foot link extending from the ankle joint to the sole. The motor is a connecting portion between the femoral link and the lower leg link and is attached to the side of the knee joint, and swings the lower leg link back and forth around the knee joint with respect to the femoral link at the side of the knee joint . Power to the motor is supplied from a battery built in the controller.

  In addition, Patent Document 3 discloses a single-legged walking support device that is attached to the affected leg of a user whose one leg is a healthy leg and the other leg is an affected leg to support the rocking motion of the affected leg. . The single-legged walking support device includes a lumbar mounting portion disposed to the side of the user's hips, a thigh link extending from the side of the hip joint to the side of the knee joint, and a side from the knee joint to the lower side. And a lower leg link portion, a torque generator disposed laterally of the hip joint, and a damper laterally disposed of the knee joint. The torque generating device is composed of a cam and a compression spring, generates torque when the affected leg swings backward by swinging out the healthy leg, and supports swinging out of the affected leg using the generated torque. There is no need for an actuator such as a motor. In addition, the initial compression amount of the compression spring can be adjusted, and the magnitude of the generated torque can be made variable.

JP 2004-344304 A JP 2012-125388 A Unexamined-Japanese-Patent No. 2013-236741

  The walking assistance device described in Patent Document 1 and the walking rehabilitation device described in Patent Document 2 both support the walking motion of the leg or a part of the leg using an electric motor, but from the battery It can not be supported if the supply of electricity from Japan continues. In addition, it is estimated that a relatively small and light battery will be used because it is impossible to provide a large and heavy battery for a user who needs to support walking. Further, Patent Document 1 and Patent Document 2 do not show a special configuration for reducing the power consumption of the electric motor. Therefore, in the assistance devices described in Patent Document 1 and Patent Document 2, it is estimated that the continuous operation time is relatively short.

  Further, the single-legged walking support device described in Patent Document 3 generates a torque for swinging out the leg by a cam and a compression spring without using an electric motor, and the continuous operation time is as described in Patent Document 1 and It is longer than Patent Document 2. However, the torque generator can be used to cope with differences in physique among users (difference in moment of inertia of lower limbs), differences in swing angles of lower limbs among users, differences in physical conditions of users, and differences in inclination of walking places, etc. The position of the determination part provided on the upper part of the compression spring is adjusted with a tool such as a minus driver, and the initial compression amount of the compression spring needs to be manually adjusted by the user, which takes time and effort.

The present invention has been made in view of such a point, and automatically adjusts the torque generated by the rocking motion by automatically adjusting the rigidity of the rocking joint device that performs the rocking motion, It is an object of the present invention to provide a stiffness control method capable of further reducing power consumption or user load.

In order to solve the above-mentioned subject, the rigidity control method concerning the present invention takes the following means. First, according to a first aspect of the present invention, there is provided a drive shaft member, a swing arm swingably supported around the drive shaft member, and a driven shaft member disposed parallel to the drive shaft member. Connected to the swing arm via power transmission means, and linked swing around the driven shaft member in conjunction with swing of the swing arm, and coupled swing motion smaller than the swing angle of the swing arm An interlocking pivoting member that interlocks and pivots at a dynamic angle, and an urging force connected to the interlocking pivoting member according to the interlocking pivoting angle, the interlocking pivoting member being in a direction opposite to the interlocking pivoting direction An elastic spring generating the biasing force, an apparent spring constant variable means for changing an apparent spring constant of the elastic spring viewed from the interlocking swing member, and an apparent spring constant variable means stiffness control of the swing joint device having a control means, the A law has apparently spring constant adjusting step, in the apparently spring constant adjusting step, the control means, using the apparent spring constant varying means, depending on the communication rocking angle, the communication The stiffness control method is to adjust the apparent spring constant of the expansion spring as viewed from the dynamic rocking member.

Next, according to a second aspect of the present invention, in the rigidity control method according to the first aspect, the apparent spring constant changing means is disposed at a position near the outer peripheral portion of the interlocking rocking member. Adjusting shaft member arranged parallel to the driven shaft member, rigidity adjusting shaft turning means for turning the rigidity adjusting shaft member, and the rigidity adjusting shaft member connected with the rigidity adjusting shaft member to turn together with the rigidity adjusting shaft member And a telescopic member, and the telescopic spring. And, a portion corresponding to one end of the expansion spring is connected to a spring fixed end which is a position away from the rigidity adjusting shaft member in the turning member, and a portion corresponding to the other end of the expansion spring is the link It is connected to a spring rocking end which is a position near the outer peripheral part of the dynamic rocking member and is coaxial with the rigidity adjusting shaft member when the interlocking rocking angle is zero, and the interlocking rocking angle is zero. In this case, the elastic spring connected to the spring fixed end and the spring swing end has a free length. Then, the control means controls the rigidity adjustment shaft turning means in the apparent spring constant adjustment step, thereby radiusing the distance from the driven shaft member to the rigidity adjustment shaft member centering on the driven shaft member. An imaginary tangent which is a tangent on the circumference of a virtual interlocking swing circle which is a circle and a tangent at the position of the rigidity adjustment shaft member, and the spring swing end when the interlocked swing angle is zero According to the interlocking rocking angle, the stiffness adjustment angle which is an angle formed by the virtual straight line connecting with the spring fixed end is adjusted according to the interlocking rocking angle, and the apparent spring constant of the elastic spring viewed from the interlocking rocking member is It is a stiffness control method to adjust.

Next, a third invention of the present invention is the stiffness control method according to the second invention, wherein the control means drives the drive when adjusting the stiffness adjustment angle in the apparent spring constant adjustment step. A swing frequency of the swing arm around the shaft member, an inertia moment around the drive shaft member in a swing target including the swing arm, a spring constant of the expansion spring, and a free length of the expansion spring And the resonance point of the expansion spring coincides with the frequency of the swing of the swing object based on the distance from the driven shaft member to the rigidity adjustment shaft member and the interlocking swing angle. The stiffness control method is to adjust the stiffness adjustment angle.

  According to the first aspect of the invention, the control means is used to control the apparent variable spring constant means according to the interlocking rocking angle, thereby to cope with the rocking motion by the rocking object including the rocking arm, Since the magnitude of the torque required to support the rocking motion is automatically adjusted, the torque can be adjusted without any trouble. Moreover, since the torque required to support the swinging motion is generated using the expansion spring, it is possible to further reduce the power consumption or the load on the user.

  According to the second aspect of the invention, the apparently variable spring constant means including the expansion spring can be specifically realized. Further, since the apparent spring constant can be adjusted simply by controlling the rigidity adjustment axis turning means from the control means and turning the turning member, the apparent spring constant can be easily adjusted.

  According to the third aspect of the present invention, the stiffness adjustment angle (pivotal angle of the pivoting member) is automatically adjusted using the control means to an appropriate angle according to the pivoting object including the pivoting arm. it can. Therefore, the generated torque can be automatically adjusted by automatically adjusting the stiffness of the swinging joint. Further, even if the swinging arm is swingingly moved by the electric motor, the swinging movement can be supported with an appropriate torque, so that the power consumption of the swinging electric motor can be further reduced. Further, even if the user swings the swing arm by the electric motor without swinging the swing arm, the swing motion can be supported with an appropriate torque, so that the load on the user can be further reduced. Can.

It is a disassembled perspective view explaining the general shape of each component which comprises the rocking-joint apparatus of 1st Embodiment, and an assembly | attachment position. It is a perspective view of the rocking-joint apparatus which assemble | attached and comprised each component shown in FIG. It is a figure explaining the state where the rocking-joint apparatus shown in FIG. 2 was mounted | worn with a user (illustration of a user's arm is abbreviate | omitted). It is a figure explaining the example of a rocking state of a thigh rocking arm, and rocking of a lower leg arm. FIG. 5 is a cross-sectional view taken along the line V-V in FIG. 4 and is a cross-sectional view illustrating the configuration of the spring unit. It is a figure explaining operation of a spring unit in case a force of a compression direction acts on a spring unit. It is a figure explaining operation | movement of a spring unit in case the force of the expansion | extension direction acts on a spring unit. It is a perspective view showing the circumference of a spring unit in case the rocking angle of a thigh rocking arm is zero. It is a perspective view which shows the circumference | surroundings of a spring unit in, when a thigh rocking | fluctuation arm rock | fluctuates ahead from the state of FIG. In the case where the driven shaft member (7), the stiffness adjustment shaft member (21D), and the spring fixing end (23C) are linearly arranged, they are schematically described according to the swing of the interlocking swing member (16) It is a figure explaining a mode that an expansion-contraction spring expands-contracts. In the case where the turning angle of the spring unit (23) is changed with respect to FIG. 10, the expansion / contraction spring described schematically according to the swinging of the interlocking swinging member (16) is there. It is a figure explaining the input-output of a control means. It is a flowchart explaining the example of the processing procedure of a control means. It is a figure explaining the procedure which calculates the rigid adjustment angle for adjusting an apparent spring constant. It is a figure explaining the example which provided two spring units in the interlocking movement rocking member.

  Hereinafter, a first embodiment of the present invention will be described in order with reference to the drawings. When X, Y, and Z axes are described in each drawing, the X, Y, and Z axes are orthogonal to each other, the Z axis direction indicates the vertically upward direction, and the X axis direction is the user. The forward direction with respect to (the user wearing the rocking joint device) is shown, and the Y-axis direction shows the right direction with respect to the user. In the present specification, the “thigh rocking arm 13” shown in FIG. 1 corresponds to the “swing arm”.

[● Overall Configuration of Swing Joint Device 1 According to First Embodiment (FIGS. 1 to 4)]
The swing joint device 1 according to the first embodiment is attached to one leg of the user (left leg in the first embodiment) to support the user's motion such as walking or running. As shown in FIG. 1, the rocking joint device 1 includes a user mounting portion indicated by reference numerals 2, 3, 4, 5, 6, 7 and a thigh rocking indicated by reference numerals 11, 12, 13, 19 Parts, a stiffness adjustment part indicated by reference numerals 16, 21, 22 and 23, and a lower thigh rocking part indicated by reference numerals 31, 32, 32P, 32B, 33, 34, 35, 36, 39 It is configured. FIG. 1 is an exploded perspective view showing the shapes, assembling positions and the like of each component of the rocking joint device 1, and FIG. 2 shows the rocking joint device 1 in a state in which each component is assembled. Further, FIG. 3 illustrates a state in which the rocking joint device 1 is attached to the user, and FIG. 4 illustrates an example of rocking of the thigh rocking arm 13 and the lower leg rocking arm 33.

● [User attachment unit composed of base 2, waist attachment 3, shoulder belt 4, control unit 5, base 2 etc. (Figs. 1 to 4)]
The base portion 2 is a member fixed to the waist mounting portion 3 and serving as a base (substrate) for holding the thigh swinging portion, the rigidity adjusting portion, and the lower thigh swinging portion. A drive shaft member 6 extending substantially parallel to the Y axis is attached to the base portion 2 at a position corresponding to the side of the hip joint of the user wearing the swing joint device 1. The driven shaft member 7 disposed parallel to the drive shaft member 6 is attached at the position where The drive shaft member 6 is inserted into a through hole 33H of a lower thigh rocking arm 33 described later, and then inserted into the through hole 13H of the thigh rocking arm 13. In addition, the driven shaft member 7 is inserted into the through hole 16H of the interlocking rocking member 16. The drive shaft 6J indicates the central axis of the drive shaft member 6, and the driven shaft 7J indicates the central axis of the driven shaft member 7.

  The waist mounting unit 3 is a member wound around the user's waist and fixed to the user's waist, and is configured to be adjustable according to the size of the user's waist. Further, the base portion 2 is fixed to the waist mounting portion 3 and one end and the other end of the shoulder belt 4 are connected.

  The shoulder belt 4 is connected at one end to the front side of the lumbar mounting portion 3 and at the other end to the rear side of the lumbar mounting portion 3 so that the length can be adjusted. ing. The user can carry the control unit 5 like a parcel on the back by adjusting the length of the shoulder belt 4 and wearing the shoulder belt 4 on his / her shoulder.

  The control unit 5 accommodates control means for controlling the electric motors 11, 21, 31 and a battery for supplying electric power to the control means and the electric motors 11, 21, 31 or the like.

● [Thigh swinging portion (Figs. 1 to 4) configured by the electric motor 11, bracket 12, thigh swinging arm 13, thigh mounting portion 19 and the like]
The thigh swinging arm 13 (corresponding to the swinging arm) is configured by a disc portion 13G having gear teeth formed on the outer peripheral surface, and an arm portion extending downward from the disc portion 13G. A through hole 13H is formed at the center of the disc portion 13G, and the drive shaft member 6 is inserted through the through hole 13H. Therefore, the thigh swinging arm 13 is swingably supported around the drive shaft member 6. The through hole 13H of the thigh swing arm 13 is disposed at a position corresponding to the side of the hip joint of the user, and the link hole 13L provided at the lower end of the thigh swing arm 13 is on the side of the knee joint of the user It is arranged at the corresponding position. The length of the lower part of the thigh swing arm 13 is adjustable, and the user can adjust the vertical position of the link hole 13L according to the position of his / her knee joint. The thigh attachment portion 19 is attached to the thigh swing arm 13, and the thigh attachment portion 19 is applied to the user's thigh (around the thigh), and the thigh swing arm 13 is attached to the user's thigh Makes it easy to wear.

  The bracket 12 is a member for fixing the electric motor 11 so that the rotation shaft of the electric motor 11 is coaxial with the drive shaft member 6, and the base portion 2 so that the through hole 12H is coaxial with the drive shaft member 6. It is fixed to The through hole 33H of the lower leg rocking arm 33 is fitted into the drive shaft member 6, and the through hole 13H of the thigh rocking arm 13 is further inserted, and then the bracket 12 is fixed to the base portion 2.

  A reduction gear 11D is attached to the tip of the electric motor 11, and the reduction gear 11D is inserted into the through hole 12H of the bracket 12 and attached to the center of the disc portion 13G of the thigh swing arm 13. The electric motor 11 is fixed to the bracket 12. Further, electric power is supplied to the electric motor 11 from the battery accommodated in the control unit 5 and the control means together with the drive signal. The electric motor 11 can rock the thigh rocking arm 13 in the front-rear direction around the drive shaft member 6 with respect to the bracket 12 (that is, the base portion 2) (see FIG. 4). Further, the electric motor 11 is provided with rotation angle detection means 11S such as an encoder. The rotation angle detection means 11S outputs a signal according to the rotation angle of the shaft of the electric motor 11 to the control means. The control means can detect the rotation angle of the reduction gear 11D based on the detection signal from the rotation angle detection means 11S and the reduction ratio of the reduction gear 11D, and detect the swing angle of the thigh swing arm 13 Is possible. The bracket 12 may be provided with angle detection means (angle sensor) for detecting the swing angle of the thigh swing arm 13 with respect to the bracket 12, and the bracket 12 may be provided with the lower thigh swing arm 33 with respect to the bracket 12. You may make it provide the angle detection means (angle sensor) which detects a rocking angle.

● [Lower leg composed of electric motor 31, bracket 32, power transmission unit (32P, 32B), lower leg swing arm 33, lower leg relay arm 34, lower leg arm 35, toe holding portion 36, lower leg mounting portion 39, etc. Swing part (Fig. 1 to 4)]
The lower thigh rocking arm 33 is formed with a through hole 33H through which the drive shaft member 6 is inserted. When the drive shaft member 6 is inserted into the through hole 33H, the lower leg swing arm 33 is swingably supported around the drive shaft member 6. A belt 32B is put on the lower leg rocking arm 33, and power is transmitted from a power transmission unit constituted by the electric motor 31, the pulley 32P and the belt 32B to rock around the drive shaft member 6.

  The upper leg of the lower leg relay arm 34 is connected swingably to the tip of the lower leg swing arm 33, and the lower end is connected swingably to the end of the parallel link forming portion 35M on the upper end side of the lower leg arm 35 It is done. The length extending downward of the lower leg relay arm 34 is adjustable, and the length of the lower leg relay arm 34 is adjusted according to the adjusted length of the thigh swing arm 13.

  The lower leg arm 35 has a substantially inverted L shape, and a link hole 35L for connecting to the link hole 13L at the lower end of the thigh swing arm 13 is formed at a position corresponding to the L-shaped bent portion. Accordingly, the lower leg arm 35 has one end of the parallel link forming portion 35M on the upper end side pivotally connected to the lower end of the lower leg relay arm 34, and the other end of the parallel link forming portion 35M is the thigh swing arm 13 It is pivotally connected to the lower end. The lower end of the lower leg arm 35 is swingably connected to the upper end of the toe holding portion 36. The length of the lower arm 35 extending downward is adjustable to fit the lower leg of the user. Further, the toe holding portion 36 is substantially L-shaped, and the lower end portion is disposed on the sole of the user's foot. Also, the lower leg attachment portion 39 is attached to the lower leg arm 35, and the lower leg attachment portion 39 is applied to the user's lower leg (around the calf) to facilitate attachment of the lower leg arm 35 to the user's lower leg portion. Do.

  The bracket 32 is a member for fixing the electric motor 31, and is fixed to the base 2. Further, through holes 32 H are formed in the bracket 32.

  The electric motor 31 has a reduction gear 31D attached to its tip, and the reduction gear 31D is inserted into the through hole 32H of the bracket 32. Further, a pulley 32P is attached to the reduction gear 31D, and a belt 32B is put on the pulley 32P and the lower leg swing arm 33. Further, electric power is supplied to the electric motor 11 from the battery accommodated in the control unit 5 and the control means together with the drive signal. The electric motor 31 can rock the lower leg rocking arm 33 in the front-rear direction around the drive shaft member 6 via the pulley 32P and the belt 32B (see FIG. 4). Further, the electric motor 31 is provided with rotation angle detection means 31S such as an encoder. The rotation angle detection means 31S outputs a signal according to the rotation angle of the shaft of the electric motor 31 to the control means. The control means is capable of detecting the rotation angle of the lower leg swing arm 33 based on the detection signal from the rotation angle detection means 31S and the reduction ratio and pulley ratio of the reduction gear 31D. It is possible to detect the movement angle.

  Next, with reference to FIG. 4, operations of swing support of the thigh UL1 of the user wearing the thigh swing arm 13 and swing support of the lower thigh UL2 of the user wearing the lower arm 35 will be described. The thigh swinging arm 13 swings around the drive shaft member 6 by the power of the electric motor 11. Similarly, the lower leg swing arm 33 swings around the drive shaft member 6 by the power of the electric motor 31. The thigh swinging arm 13, the lower thigh swinging arm 33, the lower thigh relay arm 34, and the parallel link forming portion 35M (of the lower thigh arm 35) constitute a parallel link formed of a parallelogram. Therefore, the lower leg relay arm 34 and the lower leg arm 35 are connected to the thigh swing arm 13 and the lower leg swing arm 33, and the swing angle of the thigh swing arm 13 (angle θ1 in FIG. 4) and the lower leg swing It corresponds to a rocking link member that operates based on the rocking angle of the arm 33 (angles θ1 to θ2 in FIG. 4). Note that the positions of the thigh swinging arm 13, the lower thigh swinging arm 33, the lower thigh relay arm 34, and the lower thigh arm 35 shown by solid lines in FIG. 4 are the initial positions of the arms (the positions at which the user stands upright). Do.

  When the thigh swinging arm 13 is swung forward from the initial position of the thigh swinging arm 13 at an angle θ1, as shown in FIG. 4, the user's thigh UL1 is pulled forward at an angle θ1. Can. At the same time, when the lower leg swing arm 33 is swung forward from the initial position of the lower leg swing arm 33 at an angle (θ1−θ2), as shown in FIG. The lower leg UL2 of the user can be pulled forward so as to have a slope of. Since the rocking motion of the thigh rocking arm 13 by the electric motor 11 and the rocking motion of the lower leg rocking arm 33 by the electric motor 31 can be controlled independently, the angle θ1 and the angle θ2 can be It can be freely adjusted to the desired angle. Moreover, according to this configuration, the swing-out of the thigh that requires a large torque can be performed with the torque of both the electric motor 11 and the electric motor 31, so a large-sized motor is not required.

  Further, when the thigh rocking arm 13 is rocked, the interlocking rocking member 16 interlocks to rock (reciprocate and pivot). The energy of the rocking motion is stored in the spring unit 23 via the interlocking rocking member 16 and is used for the rocking motion in the opposite direction. That is, the energy when swinging the thigh swing arm 13 forward is stored in the spring unit 23 and used when swinging the thigh swing arm 13 backward, the energy when swinging the thigh swing arm 13 backward Is stored in the spring unit and used when swinging the thigh swing arm 13 forward. Next, the rigidity adjusting unit including the spring unit 23 will be described.

[Stiffness adjustment unit (FIGS. 1 to 3) configured by interlocking rocking member 16, electric motor 21, bracket 22, spring unit 23, etc.]
The bracket 22 is coaxial with the spring locking member 16 K provided on the outer peripheral portion of the interlocking rocking member 16 when the rigidity adjustment axis member 21 D (in this case, the reduction gear) of the electric motor 21 is zero. The electric motor 21 is fixed to the position (see FIGS. 8 and 9), and is fixed to the base 2. A through hole 22H is formed in the bracket 22 at a position coaxial with the spring locking member 16 of the interlocking rocking member 16 when the interlocking rocking angle is zero. The rigidity adjustment shaft 21DJ (see FIGS. 5 to 7), which is the rotation shaft of the rigidity adjustment shaft member 21D, is parallel to the drive shaft 6J and the driven shaft 7J.

  The interlocking rocking member 16 is a disk-shaped member having gear teeth 16G formed on the outer peripheral surface. A through hole 16H is formed at the center of the interlocking rocking member 16, and the driven shaft member 7 is inserted through the through hole 16H. Accordingly, the interlocking swinging member 16 is swingably supported around the driven shaft member 7. Further, the gear teeth on the outer peripheral surface of the disc portion 13G of the thigh swing arm 13 and the gear teeth on the outer peripheral surface of the interlocking swing member 16 are engaged with each other, and interlocked with the swing motion of the thigh swing arm 13 The interlocking pivoting member 16 pivots. The diameter of the interlocking rocking member 16 is set sufficiently larger than the diameter of the disc portion 13G. For example, the number of gear teeth of the interlocking rocking member 16 with respect to the number of gear teeth of the disc portion 13G is 1:10. It is set to. In this case, for example, when the thigh swing arm 13 swings at a swing angle of 60 °, the interlocking swing member 16 swings interlockingly at a swing angle of 6 °. Further, it is a position near the outer peripheral portion of interlocking rocking member 16, which is coaxial with rigidity adjusting shaft member 21D (a reduction gear provided on the shaft of electric motor 21) when the interlocking rocking angle is zero. A spring locking member 16K (corresponding to a spring swing end, see FIG. 1) is provided in (see FIGS. 8 and 9). One end of the expansion spring of the spring unit 23 is connected to the spring locking member 16K as described later.

  The electric motor 21 has a rigid adjustment shaft member 21D attached at its tip, and the rigid adjustment shaft member 21D is inserted into the through hole 22H of the bracket 22 and attached to the mounting portion 23H of the spring unit 23. The electric motor 21 is fixed to the bracket 22. Electric power is supplied to the electric motor 21 from the battery contained in the control unit 5 and the control means together with the drive signal. Then, the electric motor 21 can turn the spring unit 23 around the rigidity adjustment shaft member 21D with respect to the bracket 22 (that is, the base portion 2) (see FIG. 4). Further, the electric motor 21 is provided with rotation angle detection means 21S such as an encoder. The rotation angle detection means 21S outputs a signal according to the rotation angle of the shaft of the electric motor 21 to the control means. The control means can detect the rotation angle of the stiffness adjustment shaft member 21D based on the detection signal from the rotation angle detection means 21S and the reduction ratio of the stiffness adjustment shaft member 21D. It is possible to detect the turning angle. The bracket 22 may be provided with angle detection means (angle sensor) for detecting the turning angle of the spring unit 23 (turning member 23A) with respect to the bracket 22. The spring unit 23 will be described in detail below.

[Configuration and operation of spring unit 23 (FIGS. 5 to 9)]
As shown in FIG. 5 (V-V cross-sectional view in FIG. 4), the spring unit 23 includes a pivoting member 23A having a mounting portion 23H, a bearing 23B, a pivoting following member 23M having a pivoting following shaft member 23C, and a shaft 23D. The elastic transmission member 23E, the washers 23F and 23G, and the elastic spring 23K.

  The rigidity adjustment shaft member 21D of the electric motor 21 is fitted in a mounting portion 23H provided in the vicinity of one end of the rotation member 23A, and the rotation member 23A rotates around the rigidity adjustment shaft 21DJ. Further, a through hole 23A1 for attaching a bearing 23B and a rocking following shaft member 23C is provided at the other end (a position away from the rigidity adjusting shaft member) of the turning member 23A.

  The rocking following shaft member 23C (corresponding to a spring fixed end) is attached via a bearing 23B at a position away from the rigidity adjusting shaft member 21D in the turning member 23A. Therefore, the rocking following member 23M having the rocking following shaft member 23C is supported so as to be able to turn around the spring support shaft 23CJ parallel to the rigidity adjusting shaft 21DJ. In the rocking follow member 23M, through holes 23M1 and 23M2 for inserting the shaft 23D are formed in a direction orthogonal to the stiffness adjustment shaft 21DJ.

  A telescopic transmission member 23E, a washer 23F, a telescopic spring 23K, and a washer 23G are fitted in the shaft 23D, and the shaft 23D is inserted through the through holes 23M1 and 23M2 of the rocking following member 23M. A spring locking member 16K (see FIG. 1) provided on the outer peripheral portion of the interlocking rocking member 16 is attached to the mounting portion 23E1 of the expansion / contraction transmission member 23E via a bearing 23N. When the stiffness adjustment shaft 21DJ and the spring swinging shaft 16KJ, which is a central axis of the spring locking member 16K, are coaxial, the expansion spring 23K has a free length, and neither compression nor expansion is possible.

  In the spring unit 23, when the interlocking rocking member 16 is moved downward from the state shown in FIG. 5 due to the above configuration, as shown in FIG. 6, the spring locking member 16K includes the expansion / contraction transmission member 23E and the washer 23F. Push it down. Then, the expansion spring 23K is compressed, and the biasing force of the expansion spring 23K works in a direction to make the distance ΔLd between the stiffness adjustment shaft 21DJ and the spring swinging axis 16KJ zero.

  Further, when the interlocking rocking member 16 moves upward from the state shown in FIG. 5, as shown in FIG. 7, the spring locking member 16K pulls up the expansion transmission member 23E, the shaft 23D and the washer 23G. Then, the expansion spring 23K is compressed, and the biasing force of the expansion spring 23K works in a direction to make the distance ΔLu between the stiffness adjustment shaft 21DJ and the spring swinging axis 16KJ zero.

  FIG. 8 is a perspective view of the periphery of the spring unit 23 when the swing angle of the thigh swing arm 13 is zero. When the swing angle of the thigh swing arm 13 is zero, the stiffness adjustment shaft 21DJ and the spring swing shaft 16KJ are coaxial, and the expansion spring 23K has a free length. The swing member 23A of the spring unit 23 can swing around the stiffness adjustment shaft 21DJ of the stiffness adjustment shaft member 21D of the electric motor 21, and the swing angle is adjusted by the electric motor 21. Further, the rocking following member 23M of the spring unit 23 can pivot around the spring support shaft 23CJ.

  FIG. 9 shows the case where the thigh swinging arm 13 swings in the direction of the code R8 from the state of FIG. 8, and shows the case where the interlocking swinging member 16 interlocks and swings in the direction of the code L8. When the thigh swinging arm 13 swings in the R8 direction, the interlocking swinging member 16 meshing with the gear teeth on the outer periphery of the disk portion 13G of the thigh swinging arm 13 interlocks and swings in the L8 direction. Then, the spring locking member 16K on the outer peripheral portion of the interlocking rocking member 16 moves in the direction away from the stiffness adjustment shaft 21DJ, and pulls the extension transmission member 23E in the direction away from the spring support shaft 23CJ. Then, the expansion spring 23K is compressed (see FIG. 7), and the biasing force generated in the expansion spring 23K is a force that causes the interlocking rocking member 16 to pivot in the direction in which the spring rocking shaft 16KJ is coaxial with the rigidity adjustment shaft 21DJ. It works as (a force to turn the interlocking rocking member 16 in the direction opposite to the L8 direction).

● [Schematic view of spring unit and rigidity adjustment angle (Fig. 10, Fig. 11)]
Next, the rigidity adjustment angle will be described using FIGS. 10 and 11. In FIGS. 10, 11, and 14, the structure of the spring unit 23 shown in FIG. 5 will be described using a spring unit 23Z in a schematic view. The spring unit 23Z shown in the schematic view leaves only the turning member 23A, the swing following shaft member 23C and the expansion spring 23K from the configuration of the spring unit 23 shown in FIG. 5, and one end of the expansion spring 23K is the swing following shaft member 23C. The other end of the expansion spring 23K is locked to the spring locking member 16K. In the case where the interlocking rocking angle shown in FIG. 10 is zero and the stiffness adjustment shaft 21DJ and the spring rocking shaft 16KJ are coaxial, the expansion spring 23K is a free length which is neither expanded nor compressed.

  In FIGS. 10 and 11, a virtual interlocking oscillation circle (in this embodiment, interlock oscillation is a circle whose radius is the distance from the driven shaft member 7 to the stiffness adjustment shaft member 21D with the driven shaft member 7 as the center A tangent line on the circumference of the outer circumferential circle of the member, and a tangent line at the position of the stiffness adjustment shaft member 21D is taken as an imaginary tangent line VS. Further, a straight line connecting the spring fixed end (corresponding to the rocking following shaft member 23C) and the spring rocking end (corresponding to the spring locking member 16K) when the interlocked rocking angle is zero is taken as an imaginary straight line V23. Further, a straight line connecting the driven shaft 7J of the driven shaft member 7 and the stiffness adjustment shaft 21DJ of the stiffness adjustment shaft member 21D is a virtual reference line VX. When the spring rocking shaft 16KJ is at a position overlapping the virtual reference line VX, the rocking angle of the thigh rocking arm 13 is zero, and the interlocking rocking angle of the interlocking rocking member 16 is zero. The virtual tangent VS and the virtual reference line VX are orthogonal to each other. Then, an angle φa in FIG. 10 and an angle φb in FIG. 11, which are angles formed by the virtual tangent VS and the virtual straight line V23, are set as the stiffness adjustment angle.

  FIG. 10 shows an example in the case where the electric motor 21 is controlled such that the rigidity adjustment angle φa is substantially at right angles. Then, the thigh swing arm 13 swings in the direction of code L10 from the state where the swing angle is zero, and the interlocking swing member 16 from the state where the interlocked swing angle is zero to the interlocked swing angle θR10 in the direction of code R10 Suppose that it rocked. In this case, the spring locking member 16K moves from the position coaxial with the rigidity adjustment shaft member 21D to the position of the spring locking member 16K 'rotated to the right by the interlocking swing angle θR10. As a result, the expansion spring 23K is in the state of the expansion spring 23K ', and is expanded by ΔLR10. The biasing force of the expansion spring 23K 'causes the interlocking rocking member 16 to rock in the direction in which the interlocking rocking angle becomes zero.

  FIG. 11 shows an example in the case where the electric motor 21 is controlled so that the rigidity adjustment angle φb is approximately 45 degrees as compared with FIG. In this case, as in FIG. 10, the thigh swing arm swings in the direction L10 from the state where the swing angle is zero, and the interlocking swing member 16 moves in the direction R10 from the state where the interlock swing angle is zero. It is assumed that the interlocking rocking angle θR10 is rocked. The expansion spring 23 K in this case is in the state of the expansion spring 23 K ′ and is expanded by ΔLR 11, but although it is the same interlocking swing angle θR 10 as in the case of FIG. It is longer than ΔLR10 shown. That is, the biasing force of the expansion spring 23K 'in FIG. 11 is larger than the biasing force of the expansion spring 23K' in FIG.

  Thus, even if the interlocking swing angle is the same, the amount of expansion and contraction of the expansion spring 23K can be changed by changing the rigidity adjustment angle. That is, when the stiffness adjustment angle is changed, it is possible to change the apparent spring constant of the expansion spring 23K as viewed from the interlocking rocking member 16. That is, by adjusting the rigidity adjustment angle, the rigidity around the drive shaft member 6 can be adjusted. The apparent spring constant of the expansion spring 23 K viewed from the interlocking rocking member 16 is smallest when the stiffness adjustment angle is at a right angle, and largest when the stiffness adjustment angle is zero (0 [°] ≦ stiffness adjustment When the angle ≦ 90 [°]).

  The spring unit 23, the rigidity adjusting shaft member 21 D, and the electric motor 21 (rigidity adjusting shaft turning device) described above constitute an apparently variable spring constant. The apparent spring constant varying means varies the apparent spring constant of the expansion spring 23 K as viewed from the interlocking rocking member 16 and varies the rigidity around the drive shaft member 6. Also, apparently, the rigidity variable means is configured by the spring constant variable means, the driven shaft member 7 and the interlocking rocking member 16.

● [Input and output of control means (Fig. 12)]
Next, input and output of the control means 50 will be described with reference to FIG. The control unit 5 houses the control means 50 and the battery 60. Further, the control unit 5 is provided with a start switch 54, a touch panel 55 which is an input / output means, a connector 61 for charging the battery 60, and the like. The control means 50 (control device) has a CPU 50A, motor drivers 51, 52, 53 and the like. In addition, although the storage device which memorize | stores the program for performing the process of the control means 50, various measurement results, etc. is also provided, illustration is abbreviate | omitted.

  The control means 50 obtains a target rocking cycle and a target rocking angle for rocking movement of the thigh rocking arm 13 as described later, and outputs a drive signal to the electric motor 11 through the motor driver 51. The electric motor 11 causes the thigh swinging arm 13 to swing at a predetermined angle at a predetermined cycle via the reduction gear 11D based on the drive signal from the control means 50. The rotation speed and rotation amount of the shaft of the electric motor 11 are detected by the rotation angle detection means 11S, and the detection signal is input to the motor driver 51 and to the CPU 50A through the motor driver 51. The CPU 50A performs feedback control so that the actual swing cycle and the actual swing angle based on the detection signal from the rotation angle detection means 11S approach the target swing cycle and the target swing angle.

  Further, as described later, the control means 50 determines a target stiffness adjustment angle so that the apparent spring constant seen from the interlocking rocking member 16 becomes an optimum value as the stiffness adjustment angle of the spring unit 23 A drive signal is output to the electric motor 21 via 52. The electric motor 21 pivots the spring unit 23 through the stiffness adjustment shaft member 21D based on the drive signal from the control means 50. The rotation speed and rotation amount of the shaft of the electric motor 21 are detected by the rotation angle detection means 21S, and the detection signal is input to the motor driver 52 and to the CPU 50A through the motor driver 52. The CPU 50A performs feedback control so that the actual turning angle based on the detection signal from the rotation angle detection means 21S approaches the target stiffness adjustment angle.

  The control means 50 obtains a target rocking cycle and a target rocking angle for rocking the lower leg rocking arm 33, as described later, and outputs a drive signal to the electric motor 31 through the motor driver 53. The electric motor 31 causes the lower leg rocking arm 33 to rock at a predetermined angle in a predetermined cycle via the reduction gear 31D, the pulley 32P and the belt 32B based on the drive signal from the control means 50. The rotation speed and rotation amount of the shaft of the electric motor 31 are detected by the rotation angle detection means 31S, and the detection signal is input to the motor driver 53 and to the CPU 50A through the motor driver 53. The CPU 50A performs feedback control so that the actual swing cycle and the actual swing angle based on the detection signal from the rotation angle detection means 31S approach the target swing cycle and the target swing angle.

  The start switch 54 is a switch for starting the control means 50. The touch panel 55 is a device for inputting the height and weight of the user, displaying the setting state, and the like. The charging connector 61 is a connector to which a charging cable is connected when the battery 60 is charged.

[Process procedure of control means (FIG. 13)]
Next, the processing procedure of the control means 50 will be described using the flowchart shown in FIG. When the user operates the start button of the control unit (step S10), the control means proceeds to step S15.

  In step S15, the control means waits for the user's initial setting input from the touch panel. After confirming the input of height and weight from the user, the control means proceeds to step S20. When the input from the user is not confirmed even after the predetermined time has elapsed, the control means, for example, sets a standard height and a standard weight set in advance, and proceeds to step S20.

  In step S20, the control means measures the walking state (or running state) of the user without energizing the electric motors 11, 21 and 31 for a predetermined period, and makes the rotation angle detecting means 11S correspond to the measurement time. The detection signal from 31S is stored in the storage device as measurement data. The shafts of the electric motors 11 and 31 are configured to idle when not energized. The shaft of the electric motor 21 is configured to be locked without idling when not energized. When the control means collects measurement data, for example, for a predetermined number of steps or for a predetermined time, the process proceeds to step S25.

  At step S25, the control means walks from the measurement data based on the detection signal from the rotation angle detection means 11S based on the rocking angle (swing amplitude) of the thigh rocking arm and the angular velocity and angular acceleration of the thigh rocking arm. Calculate the cycle (swing cycle). Similarly, from the measurement data based on the detection signal from the rotation angle detection means 31S, the control means performs the walking cycle from the rocking angle (rocking amplitude) of the lower leg rocking arm and the angular velocity and angular acceleration of the lower leg rocking arm. Calculate (oscillation cycle). Then, the control means proceeds to step S30.

  At step S30, the control means calculates the swing angle of the thigh swing arm, the swing cycle of the thigh swing arm, the height and weight of the user input at step S15, etc., calculated at step S25. A target stiffness adjustment angle which is the optimum joint stiffness is calculated, and the process proceeds to step S35. A specific calculation method of the target stiffness adjustment angle will be described later.

  In step S35, the control means controls the electric motor 21 to set the stiffness adjustment angle of the spring unit 23 (turning member 23A) to the target stiffness adjustment angle obtained in step S30, and proceeds to step S40.

  In step S40, the control means calculates the swing angle of the thigh swing arm, the swing cycle of the thigh swing arm, the swing angle of the lower thigh swing arm, and the swing cycle of the lower thigh swing arm, which are calculated in step S25. The assist pattern of the user's thigh (output pattern of drive signal to the electric motor 11, etc.) and the assist pattern of the user's lower thigh (drive signal to the electric motor 31) The output pattern is calculated, and the process proceeds to step S45.

  At step S45, the control means starts outputting a drive signal to the electric motor 11 and the electric motor 31 based on the assist pattern calculated at step S40 to rock the thigh swing arm 13 and the lower leg swing arm 33. The user's walking motion (or traveling motion) is supported so that the user makes a motion exercise and continues the user's walking motion (or traveling motion), and the process proceeds to step S50. The output of the drive signal to the electric motor 11 and the electric motor 31 continues even when shifting to another step.

  In step S50, the control means operates the electric motor 11 and the electric motor 31 to support the user's walking (or traveling) operation, and as in step S20, the rotation angle is made to correspond to the measurement time. The detection signals from the detection means 11S and 31S are stored in the storage device as measurement data, and the process proceeds to step S55. In addition, collection of measurement data is continued also when shifting to another step.

  At step S55, the control means determines whether or not the user desires to stop the support of the walking operation (or the traveling operation) based on the measurement data collected at step S50, and desires the stopping of the support. If it is determined that it is determined (Yes) that the output of the drive signal to the electric motor 11 and the electric motor 31 is stopped and the process is ended, and it is determined that the stopping of support is not desired (No) Return to S25.

● [How to calculate the target stiffness adjustment angle (Figure 14)]
Next, the calculation procedure of the target stiffness adjustment angle performed in step S30 of the flowchart shown in FIG. 13 will be described using FIG. FIG. 14 is a view schematically showing the thigh rocking arm 13, the interlocking rocking member 16, the spring locking member 16, the rocking following shaft member 23C, and the expansion spring 23K. In the example shown in FIG. 14, the rocking motion of the thigh rocking arm 13 is transmitted to the interlocking rocking member 16 via the belt VB.

  In FIG. 14, a tangent in contact with the stiffness adjustment shaft 21DJ set on the outer periphery of the interlocking rocking member 16 is taken as an imaginary tangent VS. Further, a straight line passing through the stiffness adjustment shaft 21DJ and the driven shaft 7J is assumed to be a virtual straight line VT. Further, the interlocking rocking member 16 is assumed to be a true circle of radius r centered on the driven shaft 7J. In addition, one end (a part corresponding to one end) of the expansion spring 23K is locked to the swing following shaft member 23C (corresponding to a spring fixed end) of the spring unit, and a part corresponding to the other end (the other end) of the expansion spring 23K ) Is locked to the spring locking member 16K (corresponding to the spring swinging end). The expansion spring 23K has a free length when the spring locking member 16K is coaxial with the rigidity adjustment shaft 21DJ, and this free length is L. When the interlocking rocking angle of the interlocking rocking member 16 is zero, the spring locking member 16K is assumed to be coaxial with the stiffness adjustment shaft 21DJ.

  When the interlocking rocking member 16 interlocks rocking clockwise by an angle θ from a state in which the interlocking rocking angle of the interlocking rocking member 16 is zero (a state in which the spring locking member 16K and the stiffness adjustment shaft 21DJ are coaxial), The spring locking member 16K moves from a position coaxial with the stiffness adjustment shaft 21DJ to a position indicated by reference numeral 16K ', and the position and expansion state of the expansion spring 23K are as indicated by reference numeral 23K'. In addition, let the length of the expansion-contraction spring of code | symbol 23 K 'be L'. A straight line passing through the code 16K 'and parallel to the virtual tangent VS is taken as a virtual straight line VS'. Also, set the position of the intersection of the perpendicular drawn from the position (A) to the virtual straight line VS ′ and the virtual straight line VS ′ as the position (C). The position of the code 16K 'is set to the position (B). Further, a stiffness adjustment angle which is an angle formed by an imaginary straight line V23 connecting the swing follow-up shaft member 23C and the stiffness adjustment axis 21DJ and the imaginary tangent VS is defined as an angle φ.

  By the above settings, the distance from the driven shaft 7J to the code 16K 'is r. Further, the distance from the driven shaft 7J to the virtual tangent VS is r. Further, the distance from the position (B) to the virtual straight line VT is r · sin θ. Further, the distance from the position (C) to the virtual straight line VT is L · cos φ. Further, the distance between the virtual tangent VS and the virtual straight line VS ′ is r−r · cos θ = r · (1−cos θ). Further, the distance from the position (A) to the virtual tangent VS is L · sin φ. When the interlocking rocking angle of the interlocking rocking member 16 is small enough, the displacement of the interlocking rocking member 16 in the circumferential direction, which is the moving length of the belt VB, is r · θ. is there.

Here, assuming that the walking frequency of the user is f and the angular velocity in that case is ω. The following equation (1) is established. The walking frequency f can be obtained from the measured period of walking (or running) of the user. Therefore, the value of ω in the following equation (1) can be obtained.
ω = 2 · π · f Formula (1)

Also, assuming that the spring constant when the expansion spring 23K expands and contracts in the direction of the free length is k, the apparent spring constant of the expansion spring seen from the interlocking rocking member 16 when the rigidity adjustment angle is the angle φ is k And '. Also, let I be the moment of inertia about the driven shaft 7 J including the lower limbs of the user, the thigh swing arm 13 and the interlocking swing member 16. For example, the moment of inertia I is the total mass of each member (known) swinging about the driven shaft 7J, the position of the center of gravity of the total mass (known), and the mass and center of gravity of the lower limb estimated from the weight and height of the user It is possible to obtain from the position of and the following equation (2) holds. Since the value of ω is known from the above and the moment of inertia I is also known, the spring constant k ′ can be obtained apparently from the following equation (2).
ω = √ (k '/ I)
k ′ = I · ω ² equation (2)

Further, the following equation (3) is established from the energy conservation law. Since L, r, θ, k and k ′ are already known from the above, L ′ can be obtained from equation (3).
(1/2) · k ′ · (r · θ) ² = (1/2) · k · (L′−L) ²
L ′ = L + r · θ · √ (k ′ / k) Equation (3)

Further, in FIG. 14, a triangle having a position (A), a position (B), and a position (C) as a vertex is a right triangle, and therefore the following equation (4) holds from the theorem of three squares.
(R · sin θ + L · cos φ) ² + [r · (1−cos θ) + L · sin φ] ²
= L ' ² equation (4)

By arranging the above equation (4), the following equation (5) can be obtained.
cos [(θ / 2) −φ]
^{= [L'2 -L 2 -2 ·} r 2 · (1-cosθ)] / 4 · L · r · sin (θ / 2)
Formula (5)

Here, when replacing with [L ′ ² −L ² −2 · r ² · (1−cos θ)] / 4 · L · r · sin (θ / 2) = χ, when θ = 0, χ = √ Since it is (k '/ k), the following formula (6) can be obtained. Since L ′, L, r, θ, k, k ′ are already known from the above, χ can be determined and φ can be determined. The determined angle φ is the target stiffness adjustment angle.
If φ> θ / 2, then φ = (θ / 2) + cos ⁻¹ χ
In the case of φ ≦ θ / 2, φ = (θ / 2) −cos ⁻¹式 Formula (6)

  As described above, using the control means 50, the rocking frequency (f) of the thigh rocking arm 13 around the drive shaft 6, and the driving shaft 6 in the rocking object including the thigh rocking arm 13. The moment of inertia (I), the spring constant (k) of the expansion spring 23K, the free length (L) of the expansion spring 23K, the distance (r) from the driven shaft member 7 to the stiffness adjustment shaft member, and continuous oscillation Based on the movement angle (angle θ), the stiffness adjustment angle (angle φ) is adjusted such that the resonance point of the expansion spring coincides with the frequency of the movement of the movement target.

  Thus, the energy conservation law holds true that the resonance point of the expansion spring 23K matches the frequency of the rocking object including the rocking arm 13 (the entire object rocking around the drive shaft member 6). Thus, by setting the rigidity adjustment angle φ, the power consumed by the electric motor 11 can be minimized. Note that the rigidity adjustment angle is changed by a small angle without obtaining the rigidity adjustment angle from the above equation, and after measuring the power consumption of the electric motor 11 for a predetermined cycle in the rigidity adjustment angle, the rigidity adjustment is again performed by a small angle It is also possible to repeat the measurement of the power consumption of the electric motor 11 for a predetermined cycle by changing the angle to obtain the stiffness adjustment angle with the least power consumption.

[Example of attaching two spring units to interlocking rocking member 16 (FIG. 15)]
When the expansion spring in the spring unit is effective only in the extension direction and not effective in the compression direction (for example, in the case of the expansion spring shown in the schematic view of FIG. 10), or the spring unit shown in FIG. Although the expansion spring is effective also in the direction, the spring unit 23 and the spring unit with respect to the interlocking rocking member 16 as shown in the example of FIG. You may make it attach two of 23 '. A portion corresponding to the other end of the expansion spring in the spring unit 23 is connected (locked) to a spring locking member (not shown) disposed in the vicinity of the rigidity adjustment shaft 21DJ. A portion corresponding to the other end of the inner expansion spring is connected (locked) to a spring locking member (not shown) disposed in the vicinity of the stiffness adjustment shaft 21DJ '.

  In this case, the pivoting member 23A of the spring unit 23 (swinging around the stiffness adjustment shaft 21DJ) is driven to rotate by the electric motor 21. Further, the pivoting member 23A 'of the spring unit 23' (sliding around the stiffness adjustment shaft 21DJ ') is a gear G1 attached to the pivoting member 23A, gears G2 and G3 supported by the bracket 22 (see FIG. 1), and pivoting. The turning drive force is transmitted by the gear G4 attached to the member 23A '. The rigidity adjustment angle of the spring unit 23 can be matched with the rigidity adjustment angle of the spring unit 23 'by appropriately setting the gear ratios of the adjacent gears.

  The swing joint device 1 according to the first embodiment described above is for the left leg of the user, but the base portion for the right leg (a symmetrical version of the base portion 2), the thigh swing for the right leg Parts (left-right symmetric version of each member indicated by reference numerals 11, 12, 13 and 19), stiffness adjusting part for right leg (right-left symmetric versions of each member indicated by reference numerals 16, 21, 22 and 23), From the control unit 5, both legs of the user are added by adding the lower leg rocking portions for the right leg (symbols 31, 32, 32P, 32B, 33, 34, 35, 36, 39). The walking motion (or traveling motion) of the vehicle may be supported.

● ● [Swaying joint device of the second embodiment]
In the rocking joint device of the second embodiment, the electric motor 11 (and the rotation angle detection means 11S) is omitted from the rocking joint device 1 of the first embodiment shown in FIGS. The rotation angle detection means capable of detecting the swing angle of the moving arm 13 is added. In the second embodiment, although the motion of the thigh during walking (or traveling) of the user can not be assisted by the electric motor, the motion of the lower leg can be assisted by the electric motor 31. Further, since the rigidity adjustment unit 23 is provided, by setting the rigidity adjustment angle to an appropriate angle based on the energy conservation law, it is possible to appropriately reduce the amount of exercise of the user's thighs.

  Further, as in the first embodiment, the base portion for the right leg (the left-right symmetric version of the base portion 2), and the thigh rocking portion for the right leg (the reference numerals 12, 13 and 19) Left and right symmetrical version), rigidity adjustment section for right leg (left and right symmetrical version of each member shown by reference numerals 16, 21, 22 and 23), lower thigh swinging section for right leg (reference numerals 31, 32, 32P, 32B) 33, 34, 35, 36, 39 may be added to support the walking operation (or traveling operation) of the user's legs from the control unit 5.

● ● [Swaying joint device of the third embodiment]
The rocking joint device according to the third embodiment includes the electric motor 31, the bracket 32, the pulley 32P, the belt 32B and the lower leg rocking motion from the rocking joint device 1 according to the first embodiment shown in FIGS. The arm 33, the lower leg relay arm 34, the lower leg arm 35, the toe holding portion 36, and the lower leg mounting portion 39 are omitted. In the third embodiment, the motion of the thigh during walking (or traveling) of the user is assisted by the electric motor 11, and the motion of the lower thigh is not. Since the rigidity adjustment unit is provided, power consumption of the electric motor 11 can be further reduced by setting the rigidity adjustment angle to an appropriate angle based on the energy conservation law.

  Further, as in the first embodiment, the base portion for the right leg (a symmetrical version of the base portion 2) and the thigh rocking portion for the right leg (respectively indicated by reference numerals 11, 12, 13 and 19) Left-right symmetrical version of the members) and rigidity adjustment part for right leg (left-right symmetrical version of each member indicated by reference numerals 16, 21, 22, 23) is added, and the walking operation of both legs of the user from the control unit 5 ( Alternatively, the driving operation may be supported.

● ● [Swaying joint device of the fourth embodiment]
In the rocking joint device of the fourth embodiment, the electric motor 11 (and the rotation angle detecting means 11S) is omitted from the rocking joint device of the third embodiment, and the rocking angle of the thigh rocking arm 13 is It adds a detectable rotation angle detection means. In the fourth embodiment, it is not possible to support the exercise of the lower leg in walking (or traveling) of the user. In addition, the motion of the user's thigh can not be assisted by the electric motor. However, since the stiffness adjustment unit 23 is provided, by setting the stiffness adjustment angle to an appropriate angle based on the energy conservation law, it is possible to appropriately reduce the amount of exercise of the user's thighs.

  Further, as in the first embodiment, the base portion for the right leg (the left-right symmetric version of the base portion 2), and the thigh rocking portion for the right leg (the reference numerals 12, 13 and 19) Left-right symmetrical version), rigidity adjustment part for right leg (left-right symmetrical version of each member shown with the code 16, 21, 22, 23) is added, and walking operation (or running of both legs of the user from the control unit 5) Operation) may be supported.

  Various modifications, additions, and deletions can be made without departing from the scope of the present invention as to the rigidity control method and the like of the swing joint according to the present invention.

  The stiffness control method of the swing joint described in the present embodiment is not limited to a method for supporting the swing motion of the user's lower limb, and can be applied to various objects that perform periodic swing motion. .

  In the present embodiment, the rocking motion of the thigh rocking arm 13 is transmitted to the interlocking rocking member 16 by a gear, but the power transmission means is not limited to a gear, and the power transmission means may be a belt or a pulley. It may be configured. Similarly, although the swinging rotational movement of the electric motor 31 is transmitted to the lower leg swinging arm 33 by the pulley and the belt, it is not limited to the pulley and the belt, and may be transmitted using a gear or the like. Further, in the example of FIG. 15, the turning driving force is transmitted using the turning member driving force transmission means using a gear, but the invention is not limited to the gear, and the turning driving force is transmitted via a pulley and a belt or a link mechanism. You may do it.

Reference Signs List 1 rocking joint device 2 base portion 3 waist mounting portion 4 shoulder belt 5 control unit 6 drive shaft member 6J drive shaft 7 driven shaft member 7J driven shaft member 11, 21 and 31 electric motor 11D, 31D reduction gear 11S, 21S, 31S rotation Angle detection means 12 Bracket 13 thigh swing arm 13G disc portion 16 interlocking swing member 16K spring locking member (spring swing end)
16KJ Spring rocking shaft 19 Thigh mounting part 21D rigidity adjustment shaft member (reduction gear)
21DJ rigidity adjusting shaft 22 bracket 23 spring unit 23A turning member 23C swing following shaft member (spring fixed end)
23CJ Spring Fixing Shaft 23D Shaft 23E Stretch Transmission Member 23K Stretch Spring 23M Swing Follower 32B Belt 32P Pulley 33 Lower Thigh Swing Arm 34 Lower Thigh Relay Arm 35 Lower Thigh Arm 35M Parallel Link Forming Part 39 Lower Thigh Attachment Part 50 Control Means

Claims (3)

Drive shaft member,
A swing arm supported swingably around the drive shaft member;
A driven shaft member disposed parallel to the drive shaft member;
It is connected to the swinging arm via power transmission means and interlocked swinging around the driven shaft member interlockingly with swinging of the swinging arm and interlocked swinging smaller than the swinging angle of the swinging arm An interlocking pivoting member that interlocks and pivots at an angle;
An elastic spring connected to the interlocking rocking member to generate the urging force corresponding to the interlocking rocking angle and in a direction opposite to the interlocking rocking direction of the interlocking rocking member;
Apparent spring constant varying means for varying an apparent spring constant of the expansion spring as viewed from the interlocking swing member;
Control means for controlling the apparent spring constant variable means;
A stiffness control method of a swing joint device having the
Apparently has a spring constant adjustment step,
In the apparent spring constant adjustment step, the control means
The apparent spring constant of the expansion spring as viewed from the interlocking rocking member is adjusted according to the interlocking rocking angle using the apparent spring constant variable means .
Stiffness control method. The stiffness control method according to claim 1, wherein
The apparent spring constant variable means is
A stiffness adjustment shaft member disposed at a position near the outer peripheral portion of the interlocking rocking member and disposed parallel to the driven shaft member;
Rigidity adjustment shaft turning means for turning the rigidity adjustment shaft member;
A pivoting member connected to the stiffness adjustment shaft member and pivoted with the stiffness adjustment shaft member;
Said telescopic spring, and
A point corresponding to one end of the expansion spring is connected to a spring fixed end which is a position away from the rigidity adjusting shaft member in the turning member,
A portion corresponding to the other end of the expansion spring is a position near the outer peripheral portion of the interlocking rocking member, and is a position coaxial with the rigidity adjusting shaft member when the interlocking rocking angle is zero. Connected to the swing end,
When the interlocking rocking angle is zero, the spring fixed end and the expansion spring connected to the spring rocking end have a free length,
Wherein,
In the apparent spring constant adjustment step,
A tangent line on a circle of a virtual interlocking swing circle which is a circle whose radius is a distance from the driven shaft member to the rigidity adjusting shaft member centering on the driven shaft member by controlling the rigidity adjusting shaft turning means And an angle formed by an imaginary tangent which is a tangent at the position of the rigidity adjustment shaft member and an imaginary straight line connecting the spring swing end and the spring fixed end when the interlocked swing angle is zero. Adjusting a stiffness adjustment angle according to the interlocking rocking angle to adjust an apparent spring constant of the expansion spring viewed from the interlocking rocking member;
Stiffness control method. The stiffness control method according to claim 2,
Wherein,
When adjusting the stiffness adjustment angle in the apparent spring constant adjustment step,
A swing frequency of the swing arm around the drive shaft member;
Moment of inertia about the drive shaft member in a swing target including the swing arm;
A spring constant of the elastic spring;
A free length of the telescopic spring;
A distance from the driven shaft member to the stiffness adjustment shaft member;
The rigidity adjustment angle is adjusted based on the interlocking rocking angle such that the resonance point of the expansion spring coincides with the rocking frequency of the rocking object.
Stiffness control method.