JP2011143243A - Walking assist device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a walking assist device, decreasing the forward jumping amount of a second joint part corresponding to a knee joint from a user's trunk. <P>SOLUTION: This walking assist device D includes: a support member 10, which supports a user P to transmit the load of the user; a leg link 14 having a first link 22 and a second link 26 connected thereto through a second joint part 30, which is connected to the support member 10 through a first joint part 20 including a rocking mechanism to freely rock around a rocking fulcrum 32a; and an actuator 16, wherein the actuator 16 is driven to relatively displace the first link 22 and the second link 26, thereby generating the assist force for supporting at least some of load of the user P to assist the user's P walking. The leg link 14 is provided with a third link 50 connected to the first joint part 20, and the third link 50 and the first link 22 are connected through a third joint part 52 to relatively displace. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a walking assistance device, and more particularly to a walking assistance device that is attached to the lower body of a user and assists the walking so as to reduce the amount of knee protrusion.

  2. Description of the Related Art In recent years, for example, a technique described in Patent Document 1 below is known as a walking assistance device that assists a user's walking.

  The walking assist device described in Patent Document 1 swings around a swing fulcrum on a support member through a first joint part that includes a swing mechanism and a support member that can support the user and transmit the user's load. A leg link having a second link connected to the first link and the first link via a second joint portion, and an actuator, and the actuator is driven to drive the first link and the first link. The two links are relatively displaced to generate an assist force that supports at least a part of the user's load, thereby assisting the user's walking.

JP 2007-20909 A

  The walking assist device described in Patent Document 1 is configured as described above, so that it is possible to absorb the difference in the height of the user by adjusting the angle of the second joint portion corresponding to the knee joint. On the other hand, since the second joint part protrudes forward from the trunk of the user, it increases the inertial force around the vertical axis, interferes with surrounding members, and gives an uncomfortable appearance. was there.

  Accordingly, an object of the present invention is to solve the above-described problems and to provide a walking assistance device that reduces the amount of the second joint portion corresponding to the knee joint jumping forward from the trunk of the user.

  In order to solve the above-described problem, in claim 1, the support member can support the user and transmit the user's load, and the support member via a first joint portion including a swing mechanism. A leg link having a first link, a second link connected to the first link via a second joint portion, and an actuator. In the walking assistance device for assisting a user's walking by generating an assist force that drives an actuator to relatively displace the first link and the second link to support at least a part of a user's load. The link includes a third link connected to the first joint portion, and is configured to connect the third link and the first link so as to be relatively displaceable via the third joint portion.

  In the walking assist device according to claim 2, when the actuator is driven to relatively displace the first link and the second link, the second joint portion has at least one inflection point in a side view. The trajectory is configured to be drawn.

  In the walking assist device according to claim 3, when the actuator is driven to relatively displace the first link and the second link, the first link and the second link are centered on the second joint portion. As the angle formed by the link decreases, the distance from the second joint portion to the swing fulcrum changes according to a trajectory having nonlinear characteristics in a side view.

  In the walking assistance device according to claim 4, the fourth link connected to the first link, the first link connected to the fourth link at one end, and the third link connected to the third link at the other end. And a four-bar linkage mechanism constituted by the first, third, fourth, and fifth links is configured to be driven by the actuator.

  In the walking assist device according to claim 5, the four-joint link mechanism is configured to have a dead point where at least three positions of the even number of points overlap on the same straight line.

  The walking assist device according to claim 6 is configured to drive the first link and the second link by distributing the driving force of the actuator.

  In the walking assist device according to claim 7, a second four-joint link mechanism is connected to the second link, and the driving force of the actuator is transmitted to the second link via the second four-joint link mechanism. Configured to dispense.

  In the walking assist device according to claim 8, a chain mechanism is connected to the second link, and the driving force of the actuator is distributed to the second link via the chain mechanism.

  In the walking assist device according to the ninth aspect, the second four-joint link mechanism is configured to share at least one of the paired points with the first four-joint link mechanism.

  In the walking assist device according to claim 10, the second link is provided with a link length adjusting unit capable of adjusting a link length.

  According to the first aspect of the present invention, the support member can support the user and transmit the user's load, and the support member can swing about the swing fulcrum via the first joint portion including the swing mechanism. And a leg link having a first link and a second link connected to the first link via a second joint portion, and an actuator, and driving the actuator, the first link and the second link In a walking assistance device that assists a user's walk by generating an assist force that relatively displaces the link and supports at least a part of the user's load, a third link that connects the leg link to the first joint portion Since the third link and the first link are connected so as to be relatively displaceable via the third joint part, the second joint part is set to the knee joint by appropriately setting the positional relationship of the third link and the like. When the knee from the swing fulcrum It is possible to change the distance to the section. Therefore, the amount of the knee joint protruding forward from the user's trunk can be reduced, the inertial force around the vertical axis can be reduced, and it can interfere with surrounding members or give a strange appearance. Less.

  That is, since the third link and the first link are configured to be connected to each other via the third joint portion so as to be relatively displaceable, the third joint portion is driven to swing as the angle of the second joint portion increases. It is possible to increase the distance from the moving fulcrum to the leg link tip, and as a result, the angle of the second joint when the user is standing upright can be increased, and thus the knee joint is the trunk of the user. It is possible to reduce the amount of jumping out from the front.

  In the walking assist device according to claim 2, when the actuator is driven to relatively displace the first link and the second link, the second joint portion draws a locus having at least one inflection point in a side view. In addition to the effects described above, it is possible to increase the distance from the swing fulcrum to the tip of the leg link in accordance with the increase in the angle of the second joint, in addition to the above-described effects. The angle of the second joint when the user is standing upright can be further increased.

  In the walking assist device according to claim 3, when the actuator is driven to relatively displace the first link and the second link, the angle formed by the first link and the second link with the second joint portion as a center decreases. Accordingly, since the distance from the second joint portion to the swing fulcrum changes according to the trajectory having a non-linear characteristic in a side view, in addition to the above-described effect, the second trajectory can be similarly set by appropriately setting the trajectory. As the angle of the joint portion increases, the distance from the swing fulcrum to the tip of the leg link can be increased, and as a result, the angle of the second joint portion when the user is standing upright can be further increased. it can.

  In the walking assistance device according to claim 4, a fourth link connected to the first link, a fifth link connected to the fourth link at one end, and connected to the third link at the other end In addition to the above effects, the length of the link constituting the four-joint link mechanism is configured so that the four-joint link mechanism comprising the first, third, fourth, and fifth links is driven by the actuator. By appropriately setting the length, it becomes possible to make the input / output characteristics of the four-bar linkage mechanism a curved characteristic, and the movement of the leg link can be made smooth.

  In the walking assistance device according to claim 5, the four-bar link mechanism is configured to have dead points where at least three positions of the even number of points overlap on the same straight line. It is possible to more effectively reduce the amount of protrusion of the knee joint before and after the leg is fully extended.

  In the walking assist device according to the sixth aspect of the present invention, since the driving force of the actuator is distributed to drive the first link and the second link, in addition to the above effects, one actuator is sufficient. Therefore, the structure is simplified and the weight is reduced.

  In the walking assist device according to claim 7, the second four-bar linkage mechanism is connected to the second link, and the driving force of the actuator is distributed to the second link via the second four-bar link mechanism. In addition to the above-described effects, the input / output characteristics of the second four-bar linkage mechanism are set to be curved characteristics by appropriately setting the lengths of the links constituting the second four-bar linkage mechanism. It is possible to make the movement of the leg link smoother.

  In the walking assist device according to the eighth aspect, the chain mechanism is coupled to the second link, and the driving force of the actuator is distributed to the second link via the chain mechanism. In addition, it is not necessary to consider the problem of buckling inherent in the link mechanism, and the relative displacement of the second link with respect to the first link can exceed 180 degrees, and the degree of freedom in design can be increased.

  In the walking assist device according to claim 9, the second four-bar linkage mechanism is configured to share at least one of the kinematic points with the first four-bar link mechanism. In addition, the configuration can be simplified by the number of common kinematic points.

  In the walking assist device according to claim 10, since the second link is provided with the link length adjusting unit capable of adjusting the link length, in addition to the above-described effect, the length of the second link is linked. By adjusting with the length adjustment unit, the length of the second link can be set (adjusted) according to the height of the user without increasing the amount of the knee joint protruding forward from the trunk of the user. Therefore, it is easier to use for the user, and it is less likely to give an uncomfortable appearance.

  In addition, by providing the link length adjusting unit on the second link, the amount of adjustment when setting (adjusting) the length according to the height of the user is smaller than when the link length adjusting unit is provided on the first link or the third link. Therefore, a wider range of height differences can be handled.

  Furthermore, by providing the link length adjusting section on the second link, there are no interlocking links in the lower part of the second link as compared with the case where the link length adjusting section is provided on the first link or the third link. The structure can be simplified and the adjustment (setting) itself according to the height of the user can be facilitated.

1 is a partial cross-sectional side view of a walking assist device according to a first embodiment of the present invention. It is a front view of the walking assistance apparatus shown in FIG. It is an enlarged side view of the leg link shown in FIG. It is explanatory drawing which shows the change of the leg link in the leg link shown in FIG. 1 etc. from the attitude | position which the user bent the knee to the attitude | position extended. Similarly, it is explanatory drawing which shows the locus | trajectory of the leg link in the leg link shown in FIG. 1 etc. from the attitude | position which the user bent the knee to the attitude | position extended. Similarly, in the leg link shown in FIG. 1 and the like, it is a graph showing the change characteristics of the distance from the swing fulcrum to the knee joint with respect to the knee joint angle. It is a partial cross section side view of the walking assistance apparatus which concerns on 2nd Example of this invention. FIG. 8 is an enlarged side view of the leg link shown in FIG. 7. It is explanatory drawing which shows the change of the leg link between the attitude | position which the user bent the knee in the leg link shown in FIG. 8, and the attitude | position extended. Similarly, in the leg link shown in FIG. 8, it is a graph showing the characteristics of the change in the distance from the swing fulcrum to the knee joint with respect to the knee joint angle. It is an enlarged side view of the leg link of the walking assistance apparatus which concerns on 3rd Example of this invention. It is an expansion partial perspective view of the leg link of the walking assistance apparatus which concerns on 4th Example of this invention. It is explanatory drawing similar to FIG. 5 which shows the modification of the leg link of the walk assistance apparatus which concerns on 1st Example of this invention. Similarly, it is explanatory drawing similar to FIG. 5 which shows the modification of the leg link of the walk assistance apparatus which concerns on 1st Example of this invention. Similarly, it is explanatory drawing similar to FIG. 9 which shows the modification of the leg link of the walk assistance apparatus which concerns on 2nd Example of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out a walking assist device according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a partial sectional side view of a walking assistance device according to a first embodiment of the present invention, and FIG. 2 is a front view thereof.

  Referring to FIG. 1 and FIG. 2, the symbol D indicates a walking assist device, and the walking assist device D supports the user P (shown in FIG. 1) and can support the load of the user P. A member (load transmission member) 10, a pair of left and right shoes 12 that can accommodate the foot of the user P, and a pair of left and right leg links 14 provided between the support member 10 and the pair of left and right shoes 12. The electric motor (actuator) 16 is provided, and is attached to the lower half of the user P via a fixture (not shown) provided on the support member 10 to assist the walking.

  The support member 10 has a saddle-like seat portion 10a that can be seated so that the user P straddles it, and a support frame 10b that is disposed below the seat portion 10a (in FIG. 1 and the like) and supports the seat portion 10a. And a backrest portion 10c that rises from the support frame 10b beyond the rear end (as viewed from the user P) of the seat portion 10a and can contact the waist of the user P. A hole 10d is formed in the waist pad 10c so that the user P can grip it, thereby forming a grip 10d.

  The seat portion 10a is manufactured from a cushion material, and is manufactured from a material having higher rigidity than the support frame 10b and the waistrest portion 10c. Thus, the support member 10 is configured to support the user P and transmit the load of the user P freely.

  The left and right leg links 14 are made of an aluminum material, and are connected to each other through a first joint portion 20 made of a swing mechanism (corresponding to a hip joint in humans), and a first link (thigh link) 22 and a shoe portion. 12, a second link (lower leg link) 26 connected via a second joint portion 24 having a three-axis structure (corresponding to an ankle joint in humans), and a first link 22 and a second link 26. And a third joint portion 30 (corresponding to a knee joint in human terms).

  The first joint portion 20 formed of a swing mechanism is a guide rail 32 having a circular arc when viewed from the side that is fixed to the support member 10, and a slider that is engaged with the guide rail 32 and that is fixed to one end of each leg link 14. (Movable body) 34.

  The first joint portion 20 supports the leg link 14 so as to be swingable in the longitudinal direction (front-rear direction) of the support member 10 about a swing fulcrum 32a (shown in FIG. 1) corresponding to the center of curvature of the guide rail 32. Configured as follows.

  Further, the guide rail 32 is pivotally supported on a support shaft 32b (schematically shown in FIG. 1) disposed in the longitudinal direction of the waist of the support member 10, so that the first joint portion 20 comprising the swing mechanism has the leg link 14 attached thereto. The support member 10 is configured to be swingably supported in the lateral direction about the support shaft 32b.

  As shown in FIG. 2, the shoe portion 12 includes an L-shaped connecting member 12b (as viewed from the direction of travel of the user P) that extends into the shoe 12a and can be placed on the foot of the user P, and above the connecting member 12b. The insole 12c placed on is provided. The connecting member 12 b is connected to the second link 26 of each leg link 14 via the second joint portion 24.

  The first link 22 and the second link 26 of the leg link 14 are connected to the electric motor 16, and the first link 22 and the second link 26 are relatively displaced (driven) around the third joint portion 30 by the electric motor 16. . More specifically, as shown in FIG. 12 later, the tip of the first link 22 has a bifurcated fork shape, and the second link 26 is inserted between the forks and connected.

  As shown in FIG. 1, a pressure sensor 40 is provided inside the shoe 12 a to generate an output corresponding to the pedaling force (load or pressure) of the user P and to the second joint portion 24, a biaxial force sensor 42. Is generated, and an output corresponding to the force acting on the second joint portion 24 (the resultant force of the support member 10 and the force due to the weight of each leg link 14) is generated.

  The outputs of these sensors are sent to a controller (not shown) comprising a microcomputer. The controller detects the load of the user P transmitted to the shoe part 12 with the force sensor 42, detects the pedaling force of the user P with the pressure sensor 40, and the electric motor 16 based on the outputs of the sensors 40, 42. To assist the user P in walking.

  As described above, the walking assistance device D supports the user P and transmits the user's load, and the swing fulcrum is supported on the support member 10 via the first joint portion 20 including the swing mechanism. A leg link 14 having a second link 26 coupled to the first link 22 and the first link 22 via a third joint part (second joint part) 30 while being pivotably coupled about 32a. An electric motor (actuator) 16, and driving the electric motor 16 to relatively displace the first link 22 and the second link 26 to generate an assist force that supports at least a part of the load of the user P. It is configured to assist the user P in walking. However, since the details of the operation of the walking assist device D are described in Patent Document 1 described above, further explanation is omitted.

  Since the feature of this embodiment is the structure of the leg link 14 of the walking assist device D, this will be described below.

  3 is an enlarged side view of the leg link 14 shown in FIG. 1 and the like, FIG. 4 is an explanatory view showing the change of the leg link 14 from the posture in which the user P bends the knee to the extended posture, and FIG. FIG. 6 is a diagram showing the trajectory of the leg link 14 from the posture in which the knee is bent to the posture in which the knee is extended, and FIG. 6 shows the characteristics of the change in the distance from the swing fulcrum to the knee joint with respect to the knee joint angle in the leg link 14. It is a graph. 3 is a side view of the leg link 14 shown in FIG. 4B when the user P is in a posture in which the knee is fully extended.

  As shown in FIG. 3, the leg link 14 includes a third link 50 connected to the first joint portion 20 formed of a swing mechanism, and the third link 50 and the first link 22 are connected to a fourth joint portion (third It is configured to be connected so as to be relatively displaceable via a joint portion 52.

  More specifically, the third link 50 includes a link portion 50a that is fixed to a slider (movable body) 34 that is engaged with a guide rail 32 that constitutes the swing mechanism of the first joint portion 20, and a fourth joint. It consists of a rocker arm 50b fixed via a portion 52.

  A ball bearing 52a is disposed at the fourth joint 52, and the third link 50 is rotatably connected to the first link 22 by the ball bearing 52a. A bell crank 54 is disposed on the first link 22 adjacent to the fourth joint portion 52 and the like. An output shaft of the electric motor 16 is disposed in the vicinity of the bell crank 54. The bell crank 54 is supported by a ball bearing 54a.

  The output of the electric motor 16 is transmitted to the bell crank 54, and the bell crank 54 is swung around its rotating shaft 54b. One end of the rocker arm 50 b and one crank (fourth link) 54 c of the bell crank 54 are rotatably connected by a connecting rod (fifth link) 56.

  A connecting rod 60 is disposed on the first link 22. The connecting rod 60 extends over substantially the entire length of the first link 22 and reaches the vicinity of the third joint portion 30. A driven crank arm 26a is formed on the second link 26 that is connected to the third joint portion 30 via the ball bearing 30a so as to be rotatable (relatively displaced).

  The other crank 54d of the bell crank 54 functions as a drive crank arm, is connected to the driven crank arm 26a via the connecting rod 60, transmits the output of the electric motor 16 to the driven crank arm 26a, and transmits the second link 26 to the second link 26. The first link 22 is displaced relative to the third joint 30 as a center.

  As described above, the leg link 14 including the first link 22 and the second link 26 includes the rocker arm 50b, the connecting rod 56, one crank 54c of the bell crank 54, the rotation shaft 54b of the bell crank 54, and the fourth link. A first four-joint link mechanism 62 including a link connecting the joint axes of the joint portion 52, that is, the first link 22 is provided.

  Further, the leg link 14 is adjacent to the first four-joint link mechanism 62, and connects the other crank 54d of the bell crank 54, the connecting rod 60, the third joint portion 30, and the rotation shaft 54b of the bell crank 54. 2 (ie, the first link 22) and a second four-bar linkage mechanism 64 including a driven crank arm 26a (ie, the second link 26).

  As shown in the figure, the first four-joint link mechanism 62 and the second four-joint link mechanism 64 are configured so that the rotating shaft 54b of the bell crank 54, in other words, at least one of the kinematic points constituting them is made common. Composed.

  Next, the operation of the above-described leg link 14 will be described with reference to FIGS. In FIG. 5, the trajectory of the third joint portion 30 previously proposed in Japanese Patent Application No. 2009-018291 is shown in contrast to the trajectory of the third joint portion 30.

  In the prior application, as the angle formed by the first link 22 and the second link 26 around the third joint portion 30, that is, the knee joint angle decreases, the distance from the third joint portion 30 to the swing fulcrum 32a. Thus, the third joint portion (knee joint) 30 is configured to reduce the amount of the user P projecting forward from the trunk. This embodiment intends to obtain the same effect with another configuration.

  In FIG. 3, when the bell crank 54 of the first four-bar linkage mechanism 62 is rotated counterclockwise about the rotation shaft 54b as the electric motor 16 rotates, the user P shown in FIG. The position corresponds to the posture that raised the heel.

  When the rotation of the electric motor 16 is reversed in this state, the bell crank 54 rotates clockwise in FIG. 3 about the rotation shaft 54b. When the rotation continues and the rotation of the bell crank 54 reaches an angle near the position shown in FIG. 4 (e), the three rotation axes (the even number of points) are located on the same straight line so as to have a dead center. Composed.

  That is, in the first four-bar linkage mechanism 62, the rotation shaft 50b1 of the rocker arm 50b, the rotation shaft 54c1 of one crank 54c of the bell crank 54, and the rotation shaft 54d1 of the other crank 54d of the bell crank 54 overlap on the same straight line. In other words, at least three kinematic points are arranged on the same straight line, that is, have dead points.

  Next, when the electric motor 16 is further rotated in that direction, the positions of the three rotary shafts 50b1, 54c1, 54d1 exceed the dead center, and the knee of the user P shown in FIG. Move in the direction of the turn.

  In addition, the first four-bar linkage mechanism 62 and the second four-bar linkage mechanism 64 are configured to share the rotation axis (pair point) 54b of the bell crank 54, and thus the first four-bar linkage mechanism. The movement of 62 is transmitted to the second four-bar linkage mechanism 64 through the rotation shaft 54b.

  That is, in this embodiment, the driving force of the electric motor 16 is distributed to drive the first link 22 and the second link 26, and the second link 26 is connected to the first link (the first four sections). A second four-joint link mechanism 64 (which shares the rotation axis with the link mechanism 62) is connected, and the driving force of the electric motor 16 is distributed (transmitted) to the second link 26 via the second four-joint link mechanism 64. Configured to do.

  More specifically, the movement of the crank 54d functioning as the drive crank arm of the bell crank 54 is transmitted to the driven crank arm 26a via the connecting rod 60, and the second link 26 is connected to the first link 22 with the third joint. It is configured to be relatively displaced about the axis of the portion (knee joint) 30.

  Further, in this embodiment, when the second link 26 is displaced relative to the first link 22 about the axis of the third joint portion (knee joint) 30, as shown in FIG. The portion 30 is configured to draw a locus having at least one inflection point Pi in a side view.

  Further, as the angle formed by the first link 22 and the second link 26 around the third joint portion 30, that is, the knee joint angle decreases, as shown in FIG. The distance is changed according to a trajectory having a non-linear characteristic in a side view.

  In the walking assistance device D according to the first embodiment, as described above, the leg link 14 includes the third link 50 connected to the first joint portion 20, and the third link 50 and the first link 22 are provided. Since the fourth joint portion (third joint portion) 52 is connected so as to be relatively displaceable, the third joint portion (second joint portion) can be configured by appropriately setting the positional relationship of the third link 50 and the like. When 30 is a knee joint, the distance from the swing fulcrum 32a to the knee joint can be changed. Therefore, the amount of the knee joint protruding forward from the trunk of the user P can be reduced, the inertial force around the vertical axis can be reduced, and it can interfere with surrounding members or give a strange appearance. Less.

  In other words, the third link 50 and the first link 22 are configured to be connected to each other via a fourth joint portion (third joint portion) 52 so as to be relatively displaceable. As the angle (knee joint angle) of the joint part (second joint part) 30 increases, the distance from the swing fulcrum 32a to the tip of the leg link 14 (shoe part 12) can be increased and used as a result. The angle (knee joint angle) of the third joint portion 30 when the person P is standing upright can be increased, and thus the amount of the knee joint jumping forward from the trunk of the user P can be reduced.

  Further, when the electric motor 16 is driven to relatively displace the first link 22 and the second link 26, the third joint portion (second joint portion) 30 has a locus having at least one inflection point Pi in a side view. Since it is configured as depicted, in addition to the effects described above, the trajectory is set as appropriate so that the angle from the swing fulcrum 32a to the tip of the leg link 14 can be increased as the angle of the third joint (second joint) 30 increases. The distance can be increased, and as a result, the angle of the third joint portion 30 when the user P stands upright can be further increased.

  Further, when the electric motor 16 is driven to relatively displace the first link 22 and the second link 26, an angle formed by the first link 22 and the second link 26 with the third joint part (second joint part) 30 as a center. As the distance decreases, the distance from the third joint portion 30 to the swing fulcrum 32a changes in accordance with a trajectory having a non-linear characteristic in a side view. Similarly, the distance from the swing fulcrum 32a to the tip of the leg link 14 can be increased in accordance with the increase in the angle of the third joint portion 30, and as a result, the third joint when the user P stands upright. The angle of the portion 30 can be further increased.

  Further, one crank (fourth link) 54c of the bell crank 54 connected to the first link 22 is connected to one crank 54c at one end and the third link 50 at the other end, more precisely, the first link 54c. And a connecting rod (fifth link) 56 connected to the rocker arm 50 b of the three links 50, and a first four-link mechanism 62 including the first link 22, the third link 50, the crank 54 c, and the connecting rod 56. Is driven by the electric motor (actuator) 16, and in addition to the above-described effects, the length of the link constituting the first four-joint link mechanism 62 is set appropriately, so that the first four-joint The input / output characteristic of the link mechanism 62 can be a curved characteristic, and the movement of the leg link 14 can be made smooth.

  In addition, since the first four-joint link mechanism 62 is configured to have a dead center where at least three positions of the even number of points overlap on the same straight line, in addition to the above-described effects, the leg of the user P is fully extended. It becomes possible to more effectively reduce the amount of protrusion of the front and rear knee joints.

  In addition, since the driving force of the electric motor (actuator) 16 is distributed to drive the first link 22 and the second link 26, in addition to the above-described effects, one electric motor 16 is sufficient. The structure is simple and light weight.

  Further, the second four-bar linkage mechanism is connected to the second link, and the driving force of the electric motor 16 is distributed to the second link 26 via the first four-bar linkage mechanism 62 and the second four-bar linkage mechanism 64. In addition to the above-described effects, the input and output characteristics of the second four-bar linkage mechanism 64 can be curved by appropriately setting the length of the link constituting the second four-bar linkage mechanism 64. Thus, the movement of the leg link 14 can be made smoother.

  In addition, since the second four-bar linkage mechanism 64 is configured to share at least one of the pair points with the first four-bar link mechanism 62, in addition to the above-described effects, the common pair points are separated. Only the configuration can be simplified.

  7 is a partial sectional side view of a walking assist device D according to the second embodiment of the present invention, FIG. 8 is an enlarged side view of the leg link 14 shown in FIG. 7, and FIG. 9 is a user in the leg link 14 shown in FIG. FIG. 10 is an explanatory view similar to FIG. 5 showing the change of the leg link 14 from the posture in which the knee is bent to the posture in which the knee is extended. FIG. It is a graph which shows the characteristic of change of distance.

  Description will be made with a focus on differences from the first embodiment. In the second embodiment, as shown in FIG. 8, the leg link 14 is connected to the first joint portion 20 comprising a swing mechanism. 3 link 500 is provided, and it is comprised so that the 3rd link 500 and the 1st link 22 may be connected via the 4th joint part 520 so that relative displacement is possible.

  Specifically, the third link 500 includes a portion that is fixed to the slider 34 that is engaged with the guide rail 32 that constitutes the swing mechanism of the first joint unit 20, and extends to the upper end of the first link 22. It consists of a wide plate-like link portion 500a and a rocker arm 500b connected to the link portion 500a via a fourth joint portion 520. The first link 22 is tapered near the third link 500, and one end of the rocker arm 500 b is connected to the first link 22.

  That is, one end side of the rocker arm 500b is rotatably connected to the link portion 500a via the fourth joint portion 520, and a ball bearing is disposed on the rotation shaft 500b1 on the other end side, and the rocker arm 500b is The one link 22 is rotatably connected to the proximal end side of the tapered portion.

  A crank 540 is rotatably connected to the distal end side of the tapered portion of the first link 22. In other words, the tapered portion of the first link 22 functions as the connecting rod 560, and the crank 540 disposed on the distal end side of the first link 22 is connected to the connecting rod 560 via the rotary shaft 540a having a ball bearing. .

  Further, the crank 540 is connected to the output shaft of the electric motor 16 via a rotary shaft 540b having a ball bearing on the other end side, so that the output of the electric motor 16 is transmitted to the crank 540 so that the crank 540 is centered on the rotary shaft 540b. Rocks.

  The movement of the crank 540 is transmitted to the rocker arm 500b via the connecting rod 560, and the rocker arm 500b is swung. That is, the crank 540 and the rocker arm 500b are configured as parallel links, and swing in parallel according to the output of the electric motor 16, thereby moving the first link 22 in the swing direction.

  The rocker arm 500b is provided with a rotating shaft 500b2 in the vicinity of the fourth joint portion 520, and one end of the connecting rod 600 is rotatably connected thereto. The connecting rod 600 extends over substantially the entire length of the first link 22 and is connected to the driven crank arm 26 a of the third joint portion 30.

  Thus, the output of the electric motor 16 is transmitted to the driven crank arm 26a via the crank 540, the rocker arm 500b, and the connecting rod 600, and the second link 26 is relative to the first link 22 around the third joint portion 30. Displace.

  Thus, even in the second embodiment, the leg link 14 composed of the first link 22 and the second link 26 includes the rocker arm 500b, the connecting rod 560, the crank 540, and the rotation shaft 540b of the crank 540. A first four-joint link mechanism 620 including a link connecting the joint axes of the fourth joint portion 520, that is, the first link 22 is provided.

  Further, the leg link 14 is adjacent to the first four-joint link mechanism 620, and the rocker arm 500b, more precisely, the rocker arm 500b composed of the axis connecting the rotation axes 500b1 and 500b2, the connecting rod 600, and the third joint portion 30. And a rocker arm 500b (and a connecting rod 560) and a rotation shaft 500b1 connected to each other (ie, the first link 22) and a driven crank arm 26a (ie, the second link 26). The four-bar linkage mechanism 640 is provided.

  As shown in the figure, the first four-joint link mechanism 620 and the second four-joint link mechanism 640 have at least one of the rotational axes 500b1 of the rocker arm 500b (and the connecting rod 560), in other words, at least one of the kinematic points constituting them. Configured to be common.

  Next, the operation of the leg link 14 will be described with reference to FIGS. 8 to 10 and FIG. 4 of the first embodiment.

  In FIG. 8, the position of the crank 540 is the position when the user P of FIG. 4B has fully extended his knee to the limit of the leg link 14, and thus the rotation of the electric motor 16 is reversed in that state. The crank 540 rotates counterclockwise in FIG. 8 about the rotation shaft 540b.

  Next, when the rotation of the crank 540 reaches a certain angle in the vicinity of FIG. 4E, the first four-bar linkage mechanism 620 has three rotation shafts (paired points), that is, the rotation shaft 500b1 of the rocker arm 500b and the crank 540. The rotation shaft 540a and the other rotation shaft 540b of the crank 540 overlap on the same straight line. In other words, at least three paired points are located on the same straight line, that is, have dead points.

  Next, when the electric motor 16 is further rotated in that direction, the positions of the three rotation shafts 500b1, 540a, and 540b exceed the dead point, and the direction in which the knee of the user P is bent as shown in FIG. Move towards

  Further, the first four-joint link mechanism 620 and the second four-joint link mechanism 640 are configured to share the rotation axis (pair point) 500b1 of the rocker arm 500b (and the connecting rod 560). The movement of the four-joint link mechanism 620 is transmitted to the second four-joint link mechanism 640 via the rotation shaft 500b1.

  As described above, even in the second embodiment, the driving force of the electric motor 16 is distributed to drive the first link 22 and the second link 26, and the second link 26 (the first link) The second four-bar linkage mechanism 640 is connected to the four-bar linkage mechanism 620 and the rotation axis in common, and the electric motor 16 is driven via the first four-bar link mechanism 620 and the second four-bar link mechanism 640. The force is distributed (transmitted) to the second link 26.

  Also in the second embodiment, when the second link 26 is displaced relative to the first link 22 around the axis of the third joint portion (knee joint) 30, as shown in FIG. The joint 30 draws a trajectory having at least one inflection point Pi in side view, and as the knee joint angle decreases, the distance from the third joint 30 to the swing fulcrum 32a increases as shown in FIG. The distance from the third joint portion 30 to the swinging fulcrum 32a is reduced as the non-linear characteristic in the side view, more specifically, as the knee joint angle decreases.

  Also in the second embodiment, the first four-joint link mechanism 620 and the second four-joint link mechanism 640 are configured to have the same structure as that of the first embodiment.

  As described above, even in the walking assistance device D according to the second embodiment, the leg link 14 includes the third link 500 connected to the first joint portion 20 including the swing mechanism, and the third link 500 Since the first link 22 is configured to be relatively displaceable via the fourth joint portion (third joint portion) 520, the first link 22 swings when the third joint portion (second joint portion) 30 is a knee joint. It becomes possible to change the distance from the fulcrum 32a to the knee joint. Therefore, the amount of the knee joint protruding forward from the trunk of the user P can be reduced, the inertial force around the vertical axis can be reduced, and it can interfere with surrounding members or give a strange appearance. Less. The remaining configuration and effects are not different from those of the first embodiment.

  FIG. 11 is an enlarged side view of the walking assist device D according to the third embodiment of the present invention, more specifically, the leg link 14 similar to that of FIG. 3 of the first embodiment.

  The description will focus on the differences from the previous embodiment. In the third embodiment, as indicated by the phantom line in the figure, the second four-bar linkage mechanism 64 (or 640) is replaced with a chain. A mechanism 70 is provided. The chain mechanism 70 is wound around the bell crank 54 and the third joint portion 30 via an idler 72.

  That is, even in the third embodiment, the driving force of the electric motor 16 is distributed to drive the first link 22 and the second link 26, and the chain mechanism 70 is connected to the second link 26. The driving force of the electric motor 16 is distributed (transmitted) to the second link 26 via the first four-bar linkage mechanism 62 (or 620) and the chain mechanism 70. Except for the point that the second four-bar linkage mechanism 64 is removed, the remaining configuration and effects are the same as in the first embodiment.

  Thus, in the third embodiment, the chain mechanism 70 is connected to the second link 26, and the driving force of the electric motor 16 is distributed to the second link 26 via the chain mechanism 70. In addition to the effects described above, it is not necessary to consider the problem of buckling inherent in the link mechanism, and the relative displacement of the second link 26 with respect to the first link 22 can exceed 180 degrees. Can be raised. The remaining effects are not different from the previous examples.

  In the third embodiment, it is needless to say that a similar chain mechanism 70 may be provided in place of the second four-bar linkage mechanism 640 of the second embodiment.

  FIG. 12 is an enlarged partial perspective view of the walking assist device D according to the fourth embodiment of the present invention, more specifically, the vicinity of the second link 26 of the leg link 14.

  A description will be given focusing on differences from the previous embodiment. In the fourth embodiment, the second link 26 is provided with a link length adjusting unit 80 that can adjust the link length of the second link 26. Configured. That is, the second link 26 is formed in a hollow shape and is cut halfway to be divided into an upper link piece 26b and a lower link piece 26c, and a core material 80a can be inserted into the upper and lower link pieces 26b and 26c. Is done.

  Two cylinders 80b are attached near the ends of the upper and lower link pieces 26b and 26c, respectively. A pin 80b1 is provided in the center of the cylinder 80b so that it can be pushed in, and several holes 80c (three are shown) are formed in the core member 80a in the vertical direction. The inner diameter of the hole 80c is configured to be slightly larger than the outer diameter of the pin 80b1.

  Thus, the link length adjustment part 80 is comprised from the core material 80a, the cylinder 80b, and the hole 80c. The number of cylinders 80b and holes 80c is not limited to the illustrated example.

  The user moves the upper and lower link pieces 26b, 26c up and down relative to the core material 80a according to his / her height, and then searches for one (or two or more) cylinders 80b and holes 80c closest to it. The upper and lower link pieces 26b, 26c can be fixed to the core member 80a by pushing the pin 80b1 into the corresponding hole 80c with an appropriate tool (for example, a driver) and engaging with the hole 80c.

  In the walking assist device according to the fourth embodiment, the second link 26 is configured to be provided with the link length adjusting unit 80 capable of adjusting the link length, so that the length of the second link 26 is adjusted to the link length. The length of the second link 26 is adjusted according to the height of the user without increasing the amount of the third joint portion (knee joint) 30 jumping forward from the trunk of the user by adjusting the portion 80. Can be set.

  That is, in the case of the technique described in Patent Document 1, if the length according to the height is set, the amount of the third joint portion 30 protruding forward increases, but in addition to the configuration of the first embodiment, the link length adjustment unit 80 is provided. By providing, it is easier for the user to use, and it is less likely to give an uncomfortable appearance.

  In addition, by providing the link length adjusting portion 80 on the second link 26, compared to the case where it is provided on the first link 22 or the third link 50, 500, the core material 80 a of the upper and lower link pieces 26 b, 26 c of the second link 26. Since it is only necessary to change the engagement position, the amount of adjustment when setting (adjusting) the length according to the height of the user is sufficient, so it is possible to cope with a wider range of height differences. it can.

  Furthermore, by providing the link length adjusting unit 80 in the second link 26, there is no link to be linked to the lower portion of the second link 26, compared to the case where the link length adjusting unit 80 is provided in the first link 22 or the third link 50, 500. There are few parts that require adjustment, the structure can be simplified, and adjustment (setting) itself according to the height of the user can be facilitated. The remaining configuration and effects are not different from the previous examples.

  As described above, in the first to fourth embodiments, the support member (load transmission member) 10 that can support the user P and transmit the user's load and the first joint including the swing mechanism. The first link 22 and the first link 22 are connected to the support member 10 via the second joint portion (third joint portion) 30 via the portion 20 so as to be swingable about the swing fulcrum 32a. A leg link 14 having a second link 26 and an actuator (electric motor) 16, and the actuator 16 is driven to relatively displace the first link 22 and the second link 26. A third link 50 in which the leg link 14 is connected to the first joint portion 20 in the walking assist device D that assists the walking of the user P by generating an assist force that supports at least a part of the load of P; With 500 And wherein the third link 50, 500 of the first link 22 through a third joint portion (fourth joint portion) 52,520 and composed as relatively displaceably coupled.

  When the actuator (electric motor) 16 is driven to relatively displace the first link 22 and the second link 26, the second joint portion 30 has a locus having at least one inflection point Pi in a side view. It was configured as drawing.

  Further, when the actuator (electric motor) 16 is driven to relatively displace the first link 22 and the second link 26, the first link 22 and the second link 24 centering on the second joint portion 30. As the angle formed by the knee joint angle (knee joint angle) decreases, the distance from the second joint portion 30 to the swing fulcrum 32a changes according to a trajectory having a non-linear characteristic in a side view.

  Also, a fourth link (bell crank 54, crank 540) connected to the first link 22 is connected to the fourth link at one end, and connected to the third links 50, 500 at the other end. The fifth link (connecting rods 56 and 560) is provided, and the four-joint link mechanisms 62 and 620 including the first, third, fourth, and fifth links are configured to be driven by the actuator.

  The four-joint link mechanisms 62 and 620 have at least three positions (the rotation shaft 50b1 of the rocker arm 50b, the rotation shaft 54c1 of one crank 54c of the bell crank 54, and the rotation of the other crank 54d of the bell crank 54). The shaft 54d1, the rotation shaft 500b1 of the rocker arm 500b, the rotation shaft 540a of the crank 540, and the other rotation shaft 540b of the crank 54 have dead centers that overlap on the same straight line.

  Further, the driving force of the actuator 16 is distributed to drive the first link 22 and the second link 26.

  Also, the second four-link mechanism 64, 640 is connected to the second link 26, and the driving force of the actuator 16 is distributed to the second link 26 via the second four-link mechanism. Configured.

  Further, a chain mechanism 70 is connected to the second link 26, and the driving force of the actuator 16 is distributed to the second link 26 via the chain mechanism 70.

  Further, the second four-joint link mechanisms 64 and 640 are at least one of the paired points with the first four-joint link mechanisms 62 and 620 (the rotating shaft 54b of the bell crank 54, the rocker arm 500b (and the connecting rod 560). The rotation shaft 500b1) is made common.

  Further, the second link 26 is provided with a link length adjusting unit 80 capable of adjusting the link length.

  In addition, although this invention was demonstrated from the Example, this invention is not limited to an Example, A various deformation | transformation is possible. For example, although the electric motor 16 is illustrated as an example of an actuator, it is not restricted to it.

  In the first and second embodiments, the lengths of the links constituting the first and second four-bar linkage mechanisms 62, 620, 64, and 640 can be variously changed. For example, FIGS. 13 and 14 show a modification of the first embodiment, and FIG. 15 shows a modification of the second embodiment. The present invention is also applicable to such a modified example, whereby the trajectory of the third joint portion (knee joint) 30 can be made different as shown in the figure.

  Further, although the output shaft of the electric motor 16 is arranged on the rotating shaft of the bell crank 54 in the first embodiment and the crank 540 in the second embodiment, the present invention is not limited to this, and the output shaft of the electric motor 16 is not limited thereto. Various modifications including the arrangement of are possible.

  D walking assist device, 10 support member, 12 shoe part, 12a shoe, 12b connecting member, 14 leg link, 16 electric motor (actuator), 20 first joint part, 22 first link, 24 second joint part, 26 first 2 links, 26a driven crank arm, 26b upper link piece, 26c lower link piece, 30 third joint, 32 guide rail, 32a rocking fulcrum, 32b rocking fulcrum, 34 slider, 36 roller, 40 pressure sensor, 42 force Sensor, 50, 500 Third link, 50a, 500a Link part, 50b, 500b Rocker arm, 52, 520 Fourth joint part (third joint part), 54 bell crank, 54a Ball bearing, 54b Rotating shaft, 54c One crank 54d The other crank, 540 crank, 56,560 connecting Head, 60,600 connecting rod, 62,620 first four-link mechanism, 64,640 second four-link mechanism, 70 a chain mechanism, 80 the link length adjustment unit

Claims (10)

  A support member capable of supporting a user and transmitting a user's load and a first joint portion including a swing mechanism are connected to the support member so as to be swingable about a swing fulcrum. A leg link having a first link and a second link connected to the first link via a second joint, and an actuator, and driving the actuator to relatively displace the first link and the second link In the walking assistance device that assists the walking of the user by generating an assist force that supports at least a part of the load of the user, the leg link includes a third link that is coupled to the first joint portion. The walking assist device, wherein the third link and the first link are connected to each other via a third joint so as to be relatively displaceable.   When the actuator is driven to relatively displace the first link and the second link, the second joint portion is configured to draw a trajectory having at least one inflection point in a side view. The walking assist device according to claim 1.   When the actuator is driven to relatively displace the first link and the second link, as the angle formed by the first link and the second link with respect to the second joint portion decreases, the second joint The walking assist device according to claim 1, wherein the distance from the swinging fulcrum to the swinging fulcrum changes according to a trajectory having a non-linear characteristic in a side view.   A fourth link connected to the first link; and a fifth link connected to the fourth link at one end and connected to the third link at the other end, the first, third, The walking assist device according to any one of claims 1 to 3, wherein a four-joint link mechanism including fourth and fifth links is configured to be driven by the actuator.   The walking assist device according to claim 4, wherein the four-joint link mechanism is configured to have a dead point where at least three positions of the even number of points overlap on the same straight line.   The walking assist device according to any one of claims 1 to 5, wherein the driving force of the actuator is distributed to drive the first link and the second link.   A second four-bar link mechanism is connected to the second link, and the driving force of the actuator is distributed to the second link via the second four-bar link mechanism. Item 7. A walking assistance device according to item 6.   The walking assist device according to claim 6, wherein a chain mechanism is connected to the second link, and the driving force of the actuator is distributed to the second link via the chain mechanism.   The walking assist device according to claim 7, wherein the second four-joint link mechanism is configured to share at least one of the paired points with the first four-joint link mechanism.   The walking assist device according to any one of claims 1 to 9, wherein the second link is provided with a link length adjusting unit capable of adjusting a link length.

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