CN112515925A - Walking assisting device - Google Patents

Abstract

The invention provides a walking assistance device. The walking assistance device is provided with a handle, an acting force detection unit and a control device. The control device performs forward control when a forward acting force is detected by one handle and a backward acting force is not detected by the other handle, performs backward control when the backward acting force is detected by one handle and the forward acting force is not detected by the other handle, performs right turn control when the backward acting force is detected by the right handle and the forward acting force is detected by the left handle, performs left turn control when the forward acting force is detected by the right handle and the backward acting force is detected by the left handle, and performs backward control after stopping control for a predetermined stop time when the backward acting force is not detected by both handles.

Description

Walking assisting device

Technical Field

The present disclosure relates to walking assistance devices.

Background

In recent years, various walkers have been proposed to assist a user such as an elderly person who can walk independently but needs assistance by generating an assisting force in a traveling direction by a driving means such as a motor or reducing a load when carrying a load.

For example, a cart (corresponding to a walking assistance device) described in japanese patent application laid-open No. 2017-12546 assists walking of a user by generating an assisting force for assisting movement in a traveling direction of the cart in accordance with the magnitude and direction of a handle force, which is a force for a user to hold a handle bar (corresponding to a handle) and push the cart. The handlebar is provided with a right grip sensor for detecting the grip of the right hand of the user and a left grip sensor for detecting the grip of the left hand, and when the user grips the handlebar and pushes the cart, the driving wheels assist the movement of the cart in the traveling direction of the user.

In the cart described in japanese patent application laid-open No. 2017-12546, a right grip sensor for detecting the grip of the right hand and a left grip sensor for detecting the grip of the left hand can detect whether or not the user grips the handle bar, but cannot detect the direction of the force applied to the handle bar by the user. Therefore, in the cart described in patent document 1, the user can generate the assist force in the traveling direction of the wheels by holding the handle bar, but cannot drive one of the left and right wheels to move forward and drive the other wheel to move backward, and the cart is made to turn little.

In the cart described in japanese patent application laid-open No. 2017-12546, for example, if a user who falls backward while walking out of balance pulls the handle levers to hold the posture, the cart may run backward against the user's intention and further lose balance.

Disclosure of Invention

The present disclosure provides a walking assist device that is driven by a user gripping left and right grips, and that can travel in a traveling direction (forward, backward, right turn, left turn) desired by the user in response to a force applied to the left and right grips gripped by the user, and that can prevent rearward travel against the user's intention.

According to a first aspect of the present disclosure, a walking assistance device includes: a frame; a plurality of wheels including a pair of right and left drive wheels provided on the frame; driving units for traveling, each configured to drive the pair of left and right driving wheels; a pair of left and right handles provided on the frame and configured to be held by a user; a pair of left and right handles provided on the frame, respectively, and configured to detect a front force acting forward and a rear force acting rearward in a front-rear direction of the frame, which is a front-rear direction of the frame; and a control device configured to control the driving unit for traveling. The control device performs forward control for controlling the travel drive unit so that the drive wheels are driven in the forward direction when the forward acting force is detected by the acting force detection unit on one of the handles and the backward acting force is not detected by the other of the handles, performs backward control for controlling the travel drive unit so that the drive wheels are driven in the backward direction when the backward acting force is detected by the acting force detection unit on one of the handles and the forward acting force is not detected by the other of the handles, performs backward control for detecting the backward acting force in the right handle and the forward acting force is detected by the left handle and the forward acting force is detected by the right handle, and a control unit configured to perform left turn control when the rear biasing force is detected in the left handle, and perform backward control after stopping the control unit for a predetermined stop time when the rear biasing force is detected in both the handles when the backward biasing force is not being controlled.

According to a second aspect of the present disclosure, the control device of the walking assist device of the first aspect controls the driving means for traveling respectively so that the right driving wheel is driven in the backward direction and the left driving wheel is driven in the forward direction in the right turn control, and controls the driving means for traveling respectively so that the right driving wheel is driven in the forward direction and the left driving wheel is driven in the backward direction in the left turn control.

According to a third aspect of the present disclosure, the control device of the walking assist device according to the first aspect controls the traveling drive units so that the right drive wheels are driven in the forward direction while stopping the right drive wheels in the right turn control, and controls the traveling drive units so that the left drive wheels are driven in the forward direction while stopping the left drive wheels in the left turn control.

According to a fourth aspect of the present disclosure, in the control device of the walking assistance device according to any one of the first to third aspects, when neither of the forward acting force and the rearward acting force is detected in both of the handles by the acting force detection means, stop control is performed to individually control the driving means for traveling so as to decelerate the walking assistance device in order to individually stop the driving wheels.

According to a fifth aspect of the present disclosure, the walking assistance device according to any one of the first to fourth aspects further includes a travel speed detection unit configured to detect a travel speed, which is a speed of the walking assistance device in a travel direction. The control device obtains a traveling direction acceleration, which is an acceleration in the traveling direction, based on the traveling speed detected by the traveling speed detection means, and drives the respective driving wheels so that the traveling speeds of the respective driving wheels become the predetermined speeds when the traveling speed becomes equal to or higher than a predetermined speed, or drives the respective driving wheels so that the traveling direction acceleration becomes the predetermined acceleration when the traveling direction acceleration becomes equal to or higher than a predetermined acceleration.

According to a sixth aspect of the present disclosure, in the control device of the walking assistance device according to any one of the first to fifth aspects, the acting force detection means detects, as the forward acting force, an acting force acting in the forward and backward directions of the frame when the acting force continues for a predetermined determination time or longer in each of the handles, detects, as the backward acting force, an acting force acting in the backward and forward directions of the frame when the acting force continues for the predetermined determination time or longer, and does not act on either the forward acting force or the backward acting force when the acting force does not continue for the predetermined determination time or longer in the forward and backward directions of the frame.

According to the first aspect, the left and right wheels can be independently driven to advance or retreat in accordance with the urging force applied to the left and right grips held by the user, and the vehicle can travel in the traveling direction desired by the user (forward, backward, right turn, left turn), and can be prevented from traveling backward against the user's intention.

According to the second aspect, one of the left and right drive wheels can be driven to advance and the other drive wheel can be driven to retreat, and in this case, the walking assist device can be turned while being rotated, and the turning performance can be improved.

According to the third aspect, one of the left and right drive wheels can be stopped from being driven, and the other drive wheel can be driven to move forward, so that the walking assistance device can turn while moving forward, and the user can turn more naturally while walking.

According to the fourth aspect, when the user stops holding the walking aid, the walking aid stops traveling, and therefore the walking aid does not get away from the user, which is convenient.

According to the fifth aspect, the traveling speed of the walking assistance device can be restricted so that the walking assistance device travels to a degree not exceeding the walking speed of the user, the walking assistance device does not get away from the user, and the user can walk more safely. In addition, the acceleration in the traveling direction of the walking assistance device can be restricted, and the walking assistance device can be prevented from suddenly accelerating in the traveling direction, and the user can walk more safely without being separated from the walking assistance device.

According to the sixth aspect, even when the road surface on which the user walks is, for example, a road surface having irregularities or the like on the surface, or a road surface having steps or the like, the force is not detected as the force (forward force, rearward force) unless the force applied to the handle continues for a predetermined determination time. This reduces erroneous detection of the acting force, and enables the walking assistance device to travel more appropriately in the traveling direction (forward, backward, right turn, left turn) desired by the user.

Drawings

Fig. 1 is a perspective view illustrating an external appearance of the walking assistance device according to the present embodiment.

Fig. 2 is a diagram illustrating an opened state before the main frame is folded in the left-right direction.

Fig. 3 is a diagram illustrating a state after the main frame is folded in the left-right direction.

Fig. 4 is an exploded perspective view illustrating an example of the structure of the handle and the acting force detecting unit disposed on the left handle frame.

Fig. 5 is a cross-sectional view taken along line V-V of fig. 4 when assembled.

Fig. 6 is a sectional view taken along line VI-VI of fig. 5.

Fig. 7 is a view in section from VII to VII in fig. 6.

Fig. 8 is a block diagram illustrating input and output of the control device of the walking assistance device.

Fig. 9 is a flowchart for explaining a processing procedure (overall processing) of the control device of the walking assistance device.

Fig. 10 is a flowchart for explaining a processing procedure of the input processing in the overall processing shown in fig. 9.

Fig. 11 is a flowchart illustrating a processing procedure of the forward/turning control determination processing in the overall processing shown in fig. 9.

Fig. 12 is a flowchart illustrating a processing procedure of the forward speed adjustment processing in the overall processing shown in fig. 9.

Fig. 13 is a flowchart illustrating a processing procedure of the forward speed limiting processing in the overall processing shown in fig. 9.

Fig. 14 is a flowchart illustrating a processing procedure of the forward speed drive processing in the overall processing shown in fig. 9.

Fig. 15 is a table showing control modes of the walking assist device according to the direction of the urging force of the left and right grips.

Description of reference numerals:

10 … walking assistance device; 12 … a main switch; 20L, 20R … handles; 22L … shaft member; 23L … sliding member; a 25L … handle member; 27 … screw; 28 … frame side guide groove; 30L, 30R … handle cover; 32 … through holes; 32a … bottom surface; 32B … center axis; 33 … supporting the shaft; 33A, 33B … annular grooves; 36 … ribs; 38 … spring recess; 38a … bottom face; 39 … compressing the coil spring; 40 … control device; 41-43 gaps; 50 … main frame (framework); a 50K … bag; a 50S … axis acceleration/angular velocity sensor; 51L, 51R … handle frames; 51LR … right side wall portion; 51RL … left side wall portion; 52L, 52R … wheel frames; 53 … connected body; 54L … link member; 60RL, 60RR … rear wheels (drive wheels); a 64LE, 64RE … travel speed detection unit; 64L, 64R … driving unit for running; 71L, 71R … force detection units; 72 … a base member; 72a … flat panel portion; 72B … flange portion; a through hole for 72C … position limitation; 72D … tab; 73 … moving parts; 73a … step; 73B … sensor abutment; 73C … through holes; 75 … pressure sensitive sensor; 76 … screw; ring 78 …; 90 … center angle; 221 … brake lever mounting portion; 222 … axial guide groove; 223 … screw holes; 225 … through holes; 225a … recess; 231 … cylindrical portion; 232 … clamp part; 232a … through holes; 233 … clamp portion; the L1 … distance; the L2 … distance; w1 … width (front-to-back limit range); w2 … width.

Detailed Description

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the drawings, when X, Y, and Z axes are described, the axes are orthogonal to each other. The X-axis direction indicates a direction toward the front as viewed from the walking assistance device 10, the Y-axis direction indicates a direction toward the left as viewed from the walking assistance device 10, and the Z-axis direction indicates a direction toward the vertically upper side as viewed from the walking assistance device 10. Hereinafter, with respect to the walking assistance device 10, the X-axis direction is referred to as "front", the X-axis direction is referred to as "rear", the Y-axis direction is referred to as "left", the Y-axis direction is referred to as "right", the Z-axis direction is referred to as "up", and the Z-axis direction is referred to as "down". Hereinafter, the front-rear direction of the main frame is referred to as "main frame front-rear direction (corresponding to frame front-rear direction)".

[ brief entire Structure of the Walking assistance device 10 (FIGS. 1 to 3) ]

A schematic overall structure of the walking assistance device 10 will be described with reference to fig. 1. The walking assistance device 10 includes a main frame 50 (corresponding to a frame), front wheels 60FL, 60FR, rear wheels 60RL, 60RR, driving units 64L, 64R for traveling, a battery B, a control device 40, handles 20L, 20R, handle covers 30L, 30R, a bag 50K, and the like.

The main frame 50 has: handle frames 51L, 51R extending in the vertical direction and supporting the handles 20L, 20R; and wheel frames 52L, 52R and the like that extend in the front-rear direction of the main frame 50, i.e., the main frame front-rear direction (corresponding to the frame front-rear direction), and that support wheels. The wheel frame 52L is fixed below the handle frame 51L, and the wheel frame 52R is fixed below the handle frame 51R.

Fig. 2 shows a state in which the main frame 50 is unfolded in the left-right direction, and fig. 3 shows a state in which the main frame 50 is folded in the left-right direction. In fig. 2 and 3, the bag 50K is omitted. As shown in fig. 2 and 3, the handle frame 51L and the handle frame 51R are connected by link members 54L, 54R, 55L, and 55R. As shown in fig. 2 and 3, the walking assistance device 10 can be conveniently folded as shown in fig. 3 when not in use, thereby reducing the occupied space.

Further, the walking assistance device 10 can be easily changed from the state shown in fig. 3 in which it is folded left and right to the state shown in fig. 2 in which it is opened left and right. Further, an elastically deformable coupling body 53 is provided on the upper side of the handle frame 51L and the handle frame 51R. The user enters between the wheel frame 52L and the wheel frame 52R from the open side (rear side) of the main frame 50, and operates the walking assistance device 10 by holding the handle 20L and the handle 20R with the left and right hands. Therefore, the handles 20L and 20R are provided in a left-right pair. The handles 20L and 20R (see fig. 4) will be described in detail later.

As shown in fig. 1 to 3, the handle 20L is held at the upper end of the handle frame 51L so as to extend rearward in the front-rear direction of the main frame, and a wheel frame 52L is fixed to the lower side of the handle frame 51L. The handle frame 51L is vertically extendable and retractable, and the height of the handle 20L can be adjusted according to the height of the hand of the user. Front wheels 60FL, which are turnable casters, are provided on the front side of the wheel frame 52L, and rear wheels 60RL, which are driven by the travel drive unit 64L, are provided on the rear side of the wheel frame 52L.

The handle frame 51R, the handle 20R, the wheel frame 52R, the front wheels 60FR, the travel drive unit 64R, and the rear wheels 60RR are also the same, and therefore, the description thereof is omitted. As described above, the main frame 50 is provided with a plurality of wheels (the front wheels 60FL, 60FR, the rear wheels 60RL, 60RR), and at least one of the wheels (the rear wheels 60RL, 60RR in this case) is a drive wheel.

The travel drive unit 64L is, for example, a servo-equipped electric motor, and rotationally drives the rear wheels 60RL based on a control signal from the control device 40 based on the electric power supplied from the battery B. Similarly, the travel drive unit 64R is, for example, a servo-equipped electric motor, and rotationally drives the rear wheels 60RR based on a control signal from the control device 40 based on the electric power supplied from the battery B.

The travel driving means 64L is provided with a travel speed detecting means 64LE such as an encoder, which outputs a detection signal corresponding to the rotation of the travel driving means 64L to the control device 40. The control device 40 can detect the traveling speed of the walking assistance device 10 with respect to the ground (the traveling speed based on the rear wheels 60 RL) based on the detection signal from the traveling speed detection unit 64 LE. Similarly, the travel driving means 64R is provided with a travel speed detecting means 64RE such as an encoder, which outputs a detection signal corresponding to the rotation of the travel driving means 64R to the control device 40. The control device 40 can detect the traveling speed of the walking assistance device 10 with respect to the ground (the traveling speed based on the rear wheels 60RR) based on the detection signal from the traveling speed detection means 64 RE.

The handle cover 30L is formed in a substantially box shape so as to cover an upper end portion of the handle frame 51L and the urging force detection unit 71L attached to an upper end portion of the right side wall portion 51LR of the handle frame 51L on the side facing the handle frame 51R. The handle cover 30R is formed in a substantially box shape so as to cover the upper end portion of the handle frame 51R and the urging force detection unit 71R attached to the upper end portion of the left side wall portion 51RL of the handle frame 51R on the side facing the handle frame 51L. The urging force detection means 71L, 71R (see fig. 4) will be described in detail later.

Further, a main switch 12 is provided on an upper end surface of the handle cover 30R. The main switch 12 is a switch that instructs the walking assistance device 10 to start, and when the user turns on, electric power is supplied from the battery B to the control device 40 and the travel driving units 64R and 64L, so that the walking assistance device 10 can be operated and driven for travel.

The handle 20L is held by the left hand of the user, and is provided to protrude rearward from the upper end of the handle frame 51L. As described later, the handle 20L is movable relative to the handle frame 51L (i.e., relative to the main frame 50) in a direction in which the user operates the handle from a neutral position when the user is not operating the handle to a position near the neutral position (e.g., about 1mm), that is, in a front-rear direction of the main frame (see fig. 5). That is, the range of movement of the main frame of the handle 20L in the forward and backward direction is limited to the forward and backward limit range W1 (for example, within ± 1mm from the neutral position) near the neutral position when the user is not operating (see fig. 5).

Similarly, the handle 20R is positioned to be held by the user's right hand, and is provided to project rearward from the upper end portion of the handle frame 51R. The handle 20R is movable relative to the handle frame 51R (i.e., relative to the main frame 50) in a direction from a neutral position when the user is not operating to a position near the neutral position (e.g., about 1mm), that is, in a main frame forward-backward direction. That is, the range of movement of the main frame of the handle 20R in the front-rear direction is limited to the front-rear limit range W1 (for example, within a range of ± 1mm) near the neutral position when the user is not operating (see fig. 5).

The urging force detection unit 71L detects the urging force acting on the handle 20L in the front-rear direction of the main frame by the operation of the user, and outputs a detection signal corresponding to the detected urging force to the control device 40. The control device 40 can detect a force (forward force) acting on the handle 20L forward in the main frame front-rear direction and a force (rearward force) acting on the handle 20L rearward based on a detection signal from the force detection unit 71L. That is, the control device 40 detects the forward acting force when the user presses the handle 20L and detects the backward acting force when the user pulls the handle 20L based on the detection signal from the acting force detection unit 71L. Further, the control device 40 does not detect the forward acting force or the backward acting force based on the detection signal from the acting force detection means 71L, when the user leaves the grip 20L or when the grip 20L gripped by the user is positioned at the neutral position.

Similarly, the acting force detection unit 71R outputs a detection signal corresponding to the acting force acting on the handle 20L in the main frame front-rear direction due to the operation of the user to the control device 40. The control device 40 can detect a force (forward force) acting on the handle 20R forward in the main frame front-rear direction and a force (rearward force) acting on the handle 20L rearward based on the detection signal from the force detection unit 71R. That is, the control device 40 detects the forward acting force when the user presses the handle 20R and detects the backward acting force when the user pulls the handle 20R based on the detection signal from the acting force detection unit 71R. Further, the control device 40 does not detect the forward acting force or the backward acting force based on the detection signal from the acting force detection means 71R when the user is away from the grip 20R or when the grip 20L gripped by the user is located at the neutral position.

The triaxial acceleration/angular velocity sensor 50S is provided on the main frame 50, measures acceleration for each of the three axes in the X, Y, and Z directions, measures angular velocity of rotation about each of the three axes, and outputs a detection signal based on the measurement result to the control device 40. For example, the triaxial acceleration/angular velocity sensor 50S outputs a detection signal corresponding to the inclination angle of the walking assistance device 10 with respect to the X-Y-Z axes to the control device 40 when the walking assistance device 10 travels on an inclined surface.

For example, the triaxial acceleration/angular velocity sensor 50S detects acceleration applied to the vehicle body of the walking assistance device 10 (for example, an impact on the vehicle body), and outputs a detection signal corresponding to the detected acceleration to the control device 40. The triaxial acceleration/angular velocity sensor 50S detects, for example, a pitch angle velocity (angular velocity around the Y axis), a yaw angle velocity (angular velocity around the Z axis), and a roll angle velocity (angular velocity around the X axis) of the vehicle body of the walking assistance device 10, and outputs a detection signal corresponding to the detected angular velocity to the control device 40. The control device 40 can detect the tilt angle, the magnitude of acceleration (shock), the pitch angle rate, the yaw angle rate, and the roll angle rate of the walking assistance device 10 for the X-Y-Z axes based on the detection signal from the triaxial acceleration/angular velocity sensor 50S.

Detailed structure of handle 20L and force detection unit 71L (FIGS. 4 to 7)

Next, the detailed configuration of the handles 20L, 20R and the acting force detection units 71L, 71R will be described. Further, as shown in fig. 1 and 2, since the grips 20L and 20R and the force detection units 71L and 71R are arranged in a left-right pair and in a left-right symmetry, the grip 20L and the force detection unit 71L on the left side will be described as an example, and the grip 20R and the force detection unit 71R on the right side will not be described.

As shown in fig. 4 to 7, the handle 20L includes a shaft member 22L, a slide member 23L, and a handle member 25L. Here, as shown in fig. 4, the handle 20R includes a shaft member 22R, a slide member 23R, and a handle member 25R having the same structure as the shaft member 22L, the slide member 23L, and the handle member 25L.

As shown in fig. 4 to 6, the shaft member 22L extends rearward from an upper end portion of the handle frame 51L having a substantially rectangular cross section, and is formed in a hollow shaft shape having an outer diameter slightly smaller than a width dimension of the handle frame 51L in the left-right direction. Further, a pair of brake lever attachment portions 221 having a cross-section with a substantially arc shape having an outer diameter substantially equal to the inner diameter of the cylindrical attachment cylinder portion BKL1 of the brake lever BKL and a length substantially equal to the length of the attachment cylinder portion BKL1 are provided on the base end portion side of the shaft member 22L so as to project coaxially outward in the radial direction from the outer peripheral portions at both ends in the vertical direction. An axial guide groove 222 having a predetermined width (e.g., about 30 to 40mm) is formed in the axial direction between both circumferential edges of the pair of brake lever attachment portions 221.

As shown in fig. 4 and 6, a screw hole 223 is formed in the upper brake lever mounting portion 221. The screw hole 223 is formed at a position facing the through hole BKL2 formed at the upper end of the mounting cylinder portion BKL1 when the mounting cylinder portion BKL1 of the brake lever BKL is inserted outside the shaft member 22L and is brought into contact with the grip frame 51L. Thus, the brake lever BKL can be attached to the shaft member 22L by inserting the screw 27 through the through hole BKL2 and fastening the screw to the screw hole 223 in a state where the attachment cylindrical portion BKL1 of the brake lever BKL is inserted to the outside of the shaft member 22L and brought into contact with the grip frame 51L.

As shown in fig. 4 and 5, a pair of left and right frame-side guide grooves 28 recessed in a rectangular shape in front view are provided on both side wall portions in the left and right direction of the upper end portion of the handle frame 51L, and the pair of frame-side guide grooves 28 are formed continuously in the front direction substantially in a flush manner with respect to a pair of left and right shaft-side guide grooves 222 formed on the base end portion of the shaft member 22L. The vertical width of the pair of left and right frame-side guide grooves 28 is formed to be substantially equal to the vertical width of the pair of left and right shaft-side guide grooves 222.

Further, the pair of left and right frame-side guide grooves 28 are formed with through holes (insertion holes) 32 having a rectangular cross section and penetrating left and right at the center position in the front-rear direction of the handle frame 51L. The height of the through hole 32 in the vertical direction in cross section is formed to be substantially equal to the diameter of the support shaft (shaft member) 33 having a circular cross section. The width W2 (see fig. 5) in the front-rear direction of the cross section of the through hole 32 is formed to be larger than the diameter of the support shaft 33, and the support shaft 33 is inserted so as to be movable in the front-rear direction by a predetermined dimension (for example, about 2mm to 3mm) with respect to the central axis 32B of the through hole 32 (see fig. 5).

As shown in fig. 4 and 7, on the outer peripheral surface of the shaft member 22L on the rear side of the pair of upper and lower brake lever mounting portions 221, ribs 36 having a semicircular cross-sectional shape are formed along the axial direction (front-rear direction) substantially over the entire length thereof so as to protrude radially outward from four positions at 90 ° intervals at the center angle. As shown in fig. 5 to 7, when the sliding member 23L formed in a substantially cylindrical shape is inserted and disposed outside the shaft member 22L, the radially outer tip portion of the shaft member 22L of each rib 36 abuts against the inner peripheral surface of the sliding member 23L to slidably support the sliding member 23L. Each rib 36 may be formed in a plurality of divided pieces in the longitudinal direction. The ribs 36 may be arranged at four or more positions in the circumferential direction.

Next, a schematic configuration of the slide member 23L and the handle member 25L will be described with reference to fig. 4 to 7. As shown in fig. 4 to 7, the slide member 23L includes a cylindrical portion 231 formed in a cylindrical shape, and a pair of left and right pinching portions 232 formed in an elongated plate shape extending and protruding outward in the axial direction and facing each other in the radial direction from the front end portion of the cylindrical portion 231.

As shown in fig. 4 and 6, a rubber handle member 25L formed in a bottomed cylindrical shape closed at the rear side is fitted from the rear end side to the outside of the cylindrical portion 231 of the slide member 23L. As shown in fig. 4 and 6, the handle member 25L is formed to have a length slightly shorter than the length of the cylindrical portion 231 of the slide member 23L. The grip member 25L is not limited to a bottomed cylindrical shape, and may be any shape as long as it can be gripped by a user.

As shown in fig. 6, the length of the cylindrical portion 231 of the slide member 23L is slightly longer (for example, a length of about 5mm to 10 mm) than the length of the shaft member 22L from the rear ends to the rear-side end portions of the pair of upper and lower brake lever attachment portions 221. As shown in fig. 7, the inner diameter of the cylindrical portion 231 is formed such that the radially outer tip portions of the ribs 36 slidably abut against the shaft member 22L.

Further, a pair of left and right through holes 232A each having an inner diameter substantially equal to the outer diameter of the support shaft 33 are coaxially provided so as to face each other at the distal end portions of the pair of left and right clamping portions 232. The width in the vertical direction of the pair of left and right sandwiching portions 232 is formed to be substantially the same as the width in the vertical direction of the pair of left and right shaft-side guide grooves 222 of the shaft member 22L and the width in the vertical direction of the pair of left and right frame-side guide grooves 28 formed at the upper end portion of the handle frame 51L.

As shown in fig. 4 and 5, when the cylindrical portion 231 is disposed outside the shaft member 22L, the pair of left and right pinching portions 232 are inserted into the gaps formed by the pair of left and right shaft-side guide grooves 222 of the shaft member 22L and the inner peripheral surface of the attachment tube portion BKL1 of the brake lever BKL so as to be slidable in the front-rear direction, and are inserted into the pair of left and right frame-side guide grooves 28 formed at the upper end portion of the handle frame 51L so as to be slidable in the front-rear direction.

A pair of left and right through holes 232A formed at the distal ends of the pair of left and right sandwiching portions 232 face each other with the pair of left and right frame-side guide grooves 28 interposed therebetween by the rectangular cross-sectional through holes 32. The support shaft (shaft member) 33 having a circular cross section is inserted in the left-right direction from one through hole 232A (e.g., the right through hole 232A in fig. 4) to the other through hole 232A (e.g., the left through hole 232A in fig. 4) through the through hole 32.

As shown in fig. 4 to 6, a pair of front and rear spring recesses 38 having substantially the same rectangular cross section and opening upward are formed in the center of the upper end surface of the handle frame 51L in the left-right direction so as to be recessed in the vertical direction. The pair of spring recesses 38 are spaced apart from each other about the central axis 32B of the through hole 32, and are arranged in the front-rear direction at intervals substantially equal to the diameter of the support shaft 33 or slightly smaller (for example, 0.3mm to 1.0mm smaller) than the diameter of the support shaft 33. As shown in fig. 6, the bottom surface portion 38A of each of the pair of spring recesses 38 is formed to be located at a predetermined height (e.g., a height substantially equal to the radius of the support shaft 33) below the bottom surface 32A of the through hole 32 having a rectangular cross section.

As shown in fig. 4 and 5, the width of each spring recess 38 in the left-right direction in the rectangular cross section is formed to be slightly larger (for example, approximately 0.3mm to 0.6mm) than the outer diameter of the pair of compression coil springs 39 that are pushed into each spring recess 38 from above. As shown in fig. 5 and 6, the pair of compression coil springs 39 are formed to have an outer diameter larger than the diameter of the support shaft 33, for example, an outer dimension about 2 to 3 times the diameter of the support shaft 33. As shown in fig. 5 and 6, the width of the rectangular cross section of each spring recess 38 in the front-rear direction is slightly shorter than the entire length of the compression coil spring 39 (for example, approximately 0.5mm to 2mm shorter). The pair of compression coil springs 39 have the same shape and are set to the same spring constant.

Therefore, as shown in fig. 4 and 6, the pair of compression coil springs 39 are respectively pressed into the spring concave portions 38 from above in a compressed state, and abut against the bottom surface portions 38A of the spring concave portions 38. As a result, as shown in fig. 5 and 6, the compression coil springs 39, which are press-fitted to the back sides of the pair of spring recesses 38, abut against the outer peripheral surface of the support shaft (shaft member) 33 fitted in the through hole 32, and are biased from both sides in the front-back direction such that the support shaft 33 is positioned at the center between the pair of spring recesses 38, that is, on the central axis 32B of the through hole 32.

Further, when the support shaft 33 is positioned on the central axis 32B of the through hole 32 by the biasing force of the pair of compression coil springs 39, as shown in fig. 6, slits 41 are formed between the front end surface of the cylindrical portion 231 of the slide member 23L and the rear end surfaces of the pair of upper and lower brake lever attachment portions 221 of the shaft member 22L, respectively. As shown in fig. 5 and 6, a gap 42 is formed over the entire circumference between the front end surface of the handle member 25L and the rear end surface of the mounting tube portion BKL1 of the brake lever BKL.

As shown in fig. 5, a slit 43 is formed between the front end of each clamping portion 232 of the slide member 23L and the front inner wall surface of each frame-side guide groove 28. As described later, the distance in the front-rear direction of each of the slits 41, 42, 43 is set to be greater than a distance L1 (see fig. 5 and 6) that can move in the front-rear direction from the support shaft 33 to the center axis 32B of the through hole 32 (e.g., a distance of about 1mm to 2mm from the distance L1).

Thus, when the user grips the grip member 25L and presses it forward, the support shaft 33 can be moved from the state of being positioned on the central axis 32B of the through hole 32 to the distance L1 that can be moved forward against the urging force of the compression coil spring 39. When the user grips the grip member 25L and pulls it rearward, the support shaft 33 can be moved from the state of being positioned on the center axis 32B of the through hole 32 to the distance L1 that can be moved rearward against the biasing force of the compression coil spring 39.

Next, a schematic configuration of the acting force detecting unit 71L will be described with reference to fig. 4 and 5. As shown in fig. 4, the acting force detecting unit 71L includes a base member 72, a moving member 73, and a pair of pressure sensitive sensors 75. As shown in fig. 4 and 5, the base member 72 is formed by a rectangular flat plate portion 72A and a pair of flange portions 72B, which are substantially rectangular in front view, wherein the flat plate portion 72A is attached by screws 76 so as to cover the frame-side guide grooves 28 formed at the upper end portions of the right side wall portions 51LR on the left and right sides of the handle frame 51L, and the pair of flange portions 72B extend from both side edge portions in the front-rear direction of the flat plate portion 72A over the entire length in the substantially right-angle right direction, that is, in the substantially right-angle inner direction.

The flat plate portion 72A has a stopper through hole 72C having a rectangular cross section and coaxially penetrating the center axis 32B of the through hole 32, at a position facing the through hole 32 formed in the frame-side guide groove 28. The height of the stopper through hole 72C in the vertical direction in cross section is formed to be substantially equal to the diameter of the support shaft (shaft member) 33 having a circular cross section. As shown in fig. 5, the front-rear restriction range W1, which is the width W1 in the front-rear direction (left-right direction in fig. 5) of the cross section of the stopper through hole 72C, is formed to be narrower than the width W2 in the front-rear direction of the cross section of the through hole 32.

Therefore, the support shaft 33 inserted into the stopper through hole 72C is configured to be movable in the front-rear direction by a distance L1 (for example, a distance L1 is 1mm) from a neutral position when positioned on the center axis 32B of the through hole 32 until the outer peripheral surface of the support shaft 33 comes into contact with both inner side wall surfaces in the front-rear direction of the stopper through hole 72C. As shown in fig. 4, a projecting piece 72D, which is long in the front-rear direction (left-right direction in fig. 5) when viewed from the front, projects horizontally at a predetermined height below a predetermined height of the stopper through hole 72C of the flat plate portion 72A. As shown in fig. 5, the projecting piece 72D is configured such that the lower surface of the moving member 73 attached to the right end of the support shaft 33 slidably abuts against the projecting piece 72D from above, and the moving member 73 is guided in the front-rear direction without rotating about the center axis 32B.

As shown in fig. 4 and 5, the moving member 73 has a rectangular substantially rectangular parallelepiped shape having a larger cross section than the stopper through hole 72C at a left side surface slidably contacting the flat plate portion 72A of the base member 72, and a pair of step portions 73A recessed in a left direction, that is, toward the flat plate portion 72A side are formed at both end portions in the front-rear direction of the moving member 73. Further, a pair of sensor contact portions 73B formed in a substantially cylindrical shape by an elastic body such as silicone rubber are coaxially attached to a pair of step portions 73A formed at both ends in the front-rear direction of the moving member 73 so as to protrude outward in the front-rear direction from the moving member 73.

As shown in fig. 4, the moving member 73 has a through hole 73C formed in the center thereof in front view, and having an inner diameter substantially equal to the outer diameter of the support shaft 33. As shown in fig. 5, after the right end of the support shaft 33 protruding from the stopper through hole 72C of the moving member 73 is fitted into the through hole 73C, an E-ring 78 is fixed to an annular groove 33A (see fig. 4) formed in the right end of the support shaft 33. On the other hand, the left end of the support shaft 33 is inserted into the pair of through holes 232A and 32 formed in the pair of holding portions 233 and protrudes from the through hole 232A of the left holding portion 232. An E-ring 78 is fixed to an annular groove 33B (see fig. 4) formed at the left end of the support shaft 33.

Then, as described above, the compression coil springs 39 are respectively pushed into the pair of spring concave portions 38 formed in the upper end surface of the handle frame 51L from the upper openings to the back side, whereby the support shaft 33 and the moving member 73 are positioned on the central axis 32B of the through hole 32 and the stopper through hole 72C (see fig. 5). That is, the support shaft 33 and the moving member 73 are located at the neutral position. The support shaft 33 is made of metal such as stainless steel, and the E-ring 78 is a plate-like member made of metal.

As shown in fig. 4 and 5, the pair of pressure-sensitive sensors 75 are attached to the front-rear direction inner side surfaces of the respective flange portions 72B of the base member 72 by adhesion or the like so as to face the pair of sensor contact portions 73B of the moving member 73 in the front-rear direction. The pressure-sensitive sensor 75 is an element that electrically detects pressure. For example, the pressure-sensitive sensor 75 has a pressure-sensitive resistive film composed of an electrode layer and a pressure-sensitive resistive layer.

When the biasing force is not detected, that is, when the support shaft 33 and the moving member 73 are positioned at the neutral position and the pressure sensitive sensor 75 is not pressed by the sensor contact portion 73B without the operation of the user, the electrode layer and the pressure sensitive resistance layer are not in contact with each other, and therefore, they are in an insulated state, and the resistance value of the pressure sensitive sensor 75 increases (for example, several M Ω or more). On the other hand, when the biasing force is detected, that is, when the support shaft 33 and the moving member 73 are moved in the moving direction by the user's operation and the pressure sensitive sensor 75 is pressed by the sensor contact portion 73B, the electrode layer and the pressure sensitive resistor layer come into contact with each other, and the resistance of the pressure sensitive sensor 75 corresponding to the pressure is detected. The larger the pressure, the smaller the resistance value of the pressure-sensitive sensor 75 (of the order of several k Ω).

Thus, the biasing force detection unit 71L outputs the detection signals of the pressure-sensitive sensors 75 corresponding to the movement of the support shaft 33 and the moving member 73 in the front-rear direction of the main frame when the user does not operate the handle 20L due to the biasing force generated by the user's operation, to the control device 40.

Specifically, when the handle 20L is pressed (forward acting force), the acting force detection unit 71L outputs a detection signal corresponding to the resistance corresponding to the pressure of the front pressure-sensitive sensor 75 to the control device 40, and when the handle 20L is pulled (rearward acting force), the acting force detection unit 71L outputs a detection signal corresponding to the resistance corresponding to the pressure of the rear pressure-sensitive sensor 75 to the control device 40. That is, the control device 40 can detect that the user presses the handle 20L (forward acting force), or separates from the handle 20L (the handle 20L is in the neutral position), or pulls the handle 20L (rearward acting force) based on the detection signals from the pressure-sensitive sensors 75 of the acting force detection unit 71L.

When the biasing force acting on the handle 20L forward in the main frame front-rear direction continues for a predetermined determination time or longer, the control device 40 detects the biasing force as a front biasing force by the biasing force detection unit 71L, and when the biasing force acting on the handle 20L rearward in the main frame front-rear direction continues for a predetermined determination time or longer, the control device 40 detects the biasing force as a rear biasing force by the biasing force detection unit 71L. When the main frame forward-backward direction acting force is not applied to the handle 20L for a predetermined determination time or longer, the control device 40 detects that neither the forward acting force nor the backward acting force is applied (that is, that the acting force is not detected) by the acting force detection unit 71L. This reduces erroneous detection of the acting force, and enables the vehicle to travel more appropriately in the traveling direction (forward, backward, right turn, and left turn) desired by the user. The predetermined determination time is, for example, 0.5[ sec ].

As shown in fig. 5, when the support shaft 33 and the moving member 73 are positioned at the neutral positions, gaps of a distance L2 are formed between the pressure-sensitive sensors 75 and the sensor contact portions 73B facing each other. The distance L2 is set to be smaller than a distance L1 (see fig. 5) by which the support shaft 33 and the moving member 73 can move in the front-rear direction of the main frame from a state of being positioned at the center axis 32B of the through hole 32 and the stopper through hole 72C (for example, a distance of about 0.3mm to 0.5mm smaller than the distance L1). Thus, when the handle member 25L is operated by the user and the moving member 73 moves by the distance L1 in the main frame front-rear direction, the pressure-sensitive sensor 75 in the operating direction can be reliably pressed by the sensor contact portion 73B.

[ input/output of control device 40 (FIG. 8) ]

Fig. 8 is a block diagram showing input and output of the control device 40. The control device 40 includes a control unit such as a CPU, a storage unit 44, and the like, which are not shown. Further, detection signals from the traveling speed detection means 64LE and 64RE, detection signals from the acting force detection means 71R and 71L, and detection signals from the triaxial acceleration/angular velocity sensor 50S are input to the control device 40.

The operating state of the main switch 12 is input to the control device 40. Further, the control device 40 outputs a control signal to the driving units 64L and 64R for running.

[ procedure of processing by the control device 40 (FIGS. 9 to 15) ]

Fig. 9 shows the overall processing in the processing procedure of the control device 40 (see fig. 8). When the user turns ON the main switch 12, the processing shown in fig. 9 is started at predetermined time intervals (for example, at several millisecond intervals). When the process shown in fig. 9 is started, the control device 40 advances the process to step S010. In addition, an example when the user walks so as to travel together with the walking assistance device will be described below.

In step S010, the control device 40 executes SB100 (input processing), and the process proceeds to step S030. The following describes SB100 (input processing) in detail.

In step S030, the control device 40 executes SB300 (forward/turn control determination process), and advances the process to step S050. The following describes SB300 (forward/turn control determination processing) in detail.

In step S050, the control device 40 executes SB500 (travel speed adjustment process), and advances the process to step S070. The SB500 (travel speed adjustment process) will be described in detail later.

In step S070, the control device 40 executes SB700 (traveling speed limiting process), and advances the process to step S090. The SB700 (travel speed limiting process) will be described in detail later.

In step S090, the controller 40 executes SB900 (traveling speed drive processing) and ends the processing (return). The SB900 (travel speed drive process) will be described in detail later.

[ SB 100: details of input processing (FIG. 10)

Next, the SB100 (input process) will be described in detail with reference to fig. 10. When SB100 is executed in step S010 shown in fig. 9, the control device 40 advances the process to step SB010 shown in fig. 10.

In step SB010, the control device 40 updates the direction of the force of the right handle, the right current traveling speed, the direction of the force of the left handle, the left current traveling speed, the vehicle body inclination, the pitch angle speed, the yaw angle speed, and the roll angle speed, and advances the process to step SB 030.

Specifically, the control device 40 detects a forward force acting in the forward direction and a rearward force acting in the rearward direction with respect to the main frame 50, which are the forward and rearward directions of the main frame, which are determined based on the detection signal from the force detection unit 71R (see fig. 1). When the forward acting force is detected, the direction of the acting force of the control device 40 on the right handle is set to "forward", and when the backward acting force is detected, the direction of the acting force of the control device 40 on the right handle is set to "backward". Further, when neither the forward acting force nor the rearward acting force is detected, the direction of the acting force of the control device 40 on the right handle is set to "neutral".

Further, the control device 40 detects the rotation speed of the (right) travel drive means 64R based on the detection signal from the (right) travel speed detection means 64RE of the (right) travel drive means 64R, detects the travel speed based on the rear wheels 60RR from the rotation speed of the rear wheels 60RR, and stores it as the right current travel speed (see fig. 1).

Similarly, the control device 40 stores the direction of the force of the left handle, the left present travel speed. The control device 40 stores, as the vehicle body inclination, inclination information such as the inclination angle and the inclination direction of the vehicle body of the walking assistance device 10, which is obtained based on the detection signal from the triaxial acceleration/angular velocity sensor 50S (see fig. 1). The control device 40 stores an angular velocity about the Y axis of the walking assistance device 10, which is obtained based on a detection signal from the triaxial acceleration/angular velocity sensor 50S (see fig. 1), as a pitch angular velocity, stores an angular velocity about the Z axis as a yaw angular velocity, and stores an angular velocity about the X axis as a roll angular velocity.

At step SB030, the control device 40 obtains and stores the current travel speed, which is the travel speed of the travel assisting device in the current process, based on the right current travel speed and the left current travel speed stored at step SB010, and ends the process (return). For example, the controller 40 determines the current travel speed (travel speed) by setting the current travel speed to (right travel speed + left travel speed)/2.

[ SB 300: forward/turning control determination processing (FIG. 11) ]

Next, the SB300 (forward/turn control determining process) will be described in detail with reference to fig. 11. When SB300 is executed in step S030 shown in fig. 9, control device 40 advances the process to step SB305 shown in fig. 11.

In step SB305, the control device 40 determines (temporarily) the control mode, and advances the process to step SB 310A. The (temporary) control mode is a temporary control mode until the control mode is finally determined in SB300 (forward/turn control determination process).

Specifically, the control device 40 selects one of "forward", "reverse", "right turn", "left turn" and "stop" to store as a (temporary) control mode based on the table of fig. 15 in accordance with the stored directions ("forward", "neutral" and "rearward") of the urging force of the left and right grips. For example, when the direction of the force of the right handle is "front" and the direction of the force of the left handle is "rear", the control device 40 stores "right turn" as the (provisional) control mode.

In step SB310A, the control device 40 determines whether the (previous) control mode is "back preparation", and proceeds to step SB320A when the (previous) control mode is "back preparation" (yes), and proceeds to step SB310B when the (previous) control mode is not "back preparation" (no). The control mode (last time) is the control mode finally determined in the last processing.

After the process proceeds to step SB310B, the control device 40 determines whether or not the (previous) control mode is "back", and proceeds to step SB340D when the (previous) control mode is "back" (yes), and proceeds to step SB320B when the (previous) control mode is not "back" (no).

After the process proceeds to step SB320A, the control device 40 determines whether or not the (temporary) control mode is "reverse", and proceeds to step SB330 if the (temporary) control mode is "reverse" (yes), and proceeds to step SB340A if the (temporary) control mode is not "reverse" (no).

After the process proceeds to step SB320B, the control device 40 determines whether the (temporary) control mode is "reverse", and proceeds to step SB340C when the (temporary) control mode is "reverse" (yes), and proceeds to step SB340D when the (temporary) control mode is not "reverse" (no). When the (temporary) control mode is "reverse" (yes), the control device 40 starts counting by an internal counter (not shown).

After the process proceeds to step SB330, the control device 40 determines whether or not a predetermined stop time has elapsed, and proceeds to step SB340B when the predetermined stop time has elapsed (yes), and proceeds to step SB340C when the predetermined stop time has not elapsed (no). The predetermined stop time is, for example, about 5 seconds. When the value of the internal counter reaches a value corresponding to the predetermined stop time, the control device 40 determines that the predetermined stop time has elapsed, stops counting by the internal counter, and initializes the value.

After the process proceeds to step SB340A, the control device 40 stores the mode stored as the (temporary) control mode as the (present) control mode, and proceeds to step SB 350.

After the process proceeds to step SB340B, the control device 40 stores "back" as the (present) control mode, and proceeds to step SB 350.

After the process proceeds to step SB340C, the control device 40 stores "back preparation" as the control mode (this time), and proceeds to step SB 350.

After the process proceeds to step SB340D, the control device 40 stores the mode stored as the (temporary) control mode as the (present) control mode, and proceeds to step SB 350.

After the process proceeds to step SB350, the control device 40 stores the pattern stored as the (present) control pattern as the (previous) control pattern (saves the (present) control pattern as the (previous) control pattern), and ends the process (return).

[ SB 500: details of the traveling speed adjustment processing (FIG. 12)

Next, the SB500 (travel speed adjustment process) will be described in detail with reference to fig. 12. When SB500 is executed in step S050 shown in fig. 9, the control device 40 advances the process to step SB510A shown in fig. 12.

At step SB510A, the control device 40 determines whether the control mode (this time) is "forward", and proceeds to step SB520A when the control mode (this time) is "forward" (yes), and proceeds to step SB510B when the control mode (this time) is not "forward" (no).

After the process proceeds to step SB510B, the control device 40 determines whether the control mode (this time) is "reverse", and proceeds to step SB520B when the control mode (this time) is "reverse" (yes), and proceeds to step SB510C when the control mode (this time) is not "reverse" (no).

After the process proceeds to step SB510C, the control device 40 determines whether the control mode (this time) is "left turn", and proceeds to step SB520C when the control mode (this time) is "left turn" (yes), and proceeds to step SB510D when the control mode (this time) is not "left turn" (no).

After the process proceeds to step SB510D, the control device 40 determines whether the control mode (this time) is "right turn", and proceeds to step SB520D when the control mode (this time) is "right turn" (yes), and proceeds to step SB510E when the control mode (this time) is not "right turn" (no).

After the process proceeds to step SB510E, the controller 40 determines whether the control mode (this time) is "reverse preparation", and if the control mode (this time) is "reverse preparation" (yes), the process proceeds to step SB520E, and if the control mode (this time) is not "reverse preparation" (no), the controller 40 proceeds to step SB 520F.

After the process proceeds to step SB520A, the control device 40 obtains "the current travel speed + the predetermined travel speed" and stores it as the right target speed, obtains "the current travel speed + the predetermined travel speed" and stores it as the left target speed, and ends the process (return). The predetermined travel speed is a predetermined speed amount set in advance.

After the process proceeds to step SB520B, the control device 40 obtains "the current travel speed — the predetermined travel speed" and stores it as the right target speed, obtains "the current travel speed — the predetermined travel speed" and stores it as the left target speed, and ends the process (return).

After the process proceeds to step SB520C, the control device 40 obtains "the current travel speed + the predetermined travel speed" and stores it as the right target speed, obtains "the current travel speed-the predetermined travel speed" and stores it as the left target speed, and ends the process (return).

After the process proceeds to step SB520D, the control device 40 obtains "the current travel speed — the predetermined travel speed" and stores it as the right target speed, obtains "the current travel speed + the predetermined travel speed" and stores it as the left target speed, and ends the process (return).

After the process proceeds to step SB520E, control device 40 stores "speed 0" as the right target speed and "speed 0" as the left target speed, and ends the process (return).

After the process proceeds to step SB520F, the control device 40 obtains a speed corresponding to the heading "speed 0 (stop) deceleration" and stores it as the right target speed, obtains a speed corresponding to the heading speed 0 (stop) deceleration "and stores it as the left target speed, and ends the process (return). Specifically, the controller 40 obtains the speed obtained by subtracting a predetermined speed from the current travel speed so as to gradually decelerate toward the speed 0 (stop), and stores the speed as the right target speed and the left target speed, respectively.

[ SB 700: details of traveling speed limiting processing (FIG. 13) ]

Next, the SB700 (travel speed limiting process) will be described in detail with reference to fig. 13. When SB700 is executed in step S070 shown in fig. 9, control device 40 advances the process to step SB710A shown in fig. 13.

In step SB710A, the control device 40 determines whether or not the right target speed is equal to or higher than the front limit speed (the right target speed is equal to or higher than the front limit speed), and if the right target speed is equal to or higher than the front limit speed (yes), the process proceeds to step SB730A, and if the right target speed is not equal to or higher than the front limit speed (no), the process proceeds to step SB 720A. The forward limit speed is a predetermined speed set in advance, and is a limit speed of the walking assistance device during forward travel. The forward limit speed is, for example, 3 to 4 km/h.

After the process proceeds to step SB720A, the control device 40 determines whether or not the right target speed is equal to or higher than the rear limit speed (the right target speed is equal to or lower than the rear limit speed), and if the right target speed is equal to or higher than the rear limit speed (yes), the process proceeds to step SB740A, and if the right target speed is not equal to or higher than the rear limit speed (no), the process proceeds to step SB 710B. The rear limit speed is a predetermined speed set in advance, and is a limit speed of the walking assistance device during backward traveling. The rear limit speed is, for example, 1 km/h.

After the process proceeds to step SB730A, control device 40 stores the front limit speed as the right target speed and the front limit speed as the left target speed, and proceeds to step SB 710B.

After the process proceeds to step SB740A, control device 40 stores the rear limit speed as the right target speed, stores the rear limit speed as the left target speed, and proceeds to step SB 710B.

The processing in steps SB710B to SB740B is processing for determining the left target speed, and is the same as the processing in steps SB710A to SB740A for determining the right target speed, and therefore, the description thereof is omitted.

By SB700 (traveling speed limitation processing), the walking assistance device can be caused to travel to such an extent that the walking speed of the user is not exceeded, and the user can walk more safely.

[ SB 900: details of traveling speed drive processing (FIG. 14) ]

Next, the SB900 (travel speed drive processing) will be described in detail with reference to fig. 14. When SB900 is executed in step S090 shown in fig. 9, the controller 40 advances the process to step SB910 shown in fig. 14.

In step SB910, the control device 40 controls the (right) travel driving means 64R so as to achieve the right target speed, controls the (left) travel driving means 64L so as to achieve the left target speed, and ends the processing (return).

Details of the control mode of the walking assistance device (fig. 11, 12, and 15)

Next, the control mode of the walking assistance device will be described in detail with reference to fig. 11, 12, and 15. The horizontal item in fig. 15 indicates the direction of the force of the right handle, and the vertical item indicates the direction of the force of the left handle. Based on the information from the force detection units 71L, 71R, "front" indicates that the force applied to the handle is a forward force, and "rear" indicates that the force applied to the handle is a rear force. "neutral" means that no force is applied to the handle, neither "forward" nor "rearward".

In the control mode "forward", the control device 40 performs forward control for controlling the travel drive units 64L and 64R so as to drive the drive wheels 60RL and 60RR in the forward direction, respectively, when a forward force ("forward") is detected on one of the left and right grips (20R and 20L) and a rearward force ("rearward") is not detected on the other grip (see fig. 1).

In the control mode "reverse", the control device 40 performs reverse control for controlling the travel drive units 64L and 64R so as to drive the drive wheels 60RL and 60RR in the reverse direction, respectively, when a rearward acting force ("rearward") is detected on one of the left and right grips (20R and 20L) and a forward acting force ("forward") is not detected on the other grip.

In the control mode "right turn", the control device 40 performs right turn control when detecting a rearward acting force ("rearward") in the right grip 20R and a forward acting force ("forward") in the left grip 20L. Specifically, in the right-turn control, the control device 40 controls the travel drive units 64L and 64R so as to drive the right drive wheel 60RR in the backward direction and the left drive wheel 60RL in the forward direction, respectively. In this case, the walking assistance device can be turned while being rotated, and the turning performance can be improved.

In the control mode "left turn", the control device 40 performs left turn control when detecting a forward force ("forward") in the right grip 20R and a rearward force ("rearward") in the left grip 20L. Specifically, in the left-turn control, the control device 40 controls the travel drive units 64L and 64R so as to drive the right drive wheel 60RR in the forward direction and the left drive wheel 60RL in the backward direction, respectively. In this case, the walking assistance device can be turned while being rotated, and the turning performance can be improved.

In the control mode "stop", the control device 40 performs stop control when neither the forward acting force nor the backward acting force is detected in both the handles (20R, 20L). Specifically, during the stop control, the control device 40 stops the control of each of the travel drive units 64L and 64R. Therefore, the walking assisting device can not be separated from the user, and is convenient.

In the control mode "reverse preparation", when the control device 40 is not in the reverse control, the control device stops the control for a predetermined stop time when the rearward acting force ("rearward") is detected in both the handles (20R and 20L), and then performs the reverse control. Thus, the walk assist device is controlled to retreat only when the user desires to retreat, and therefore, the walk assist device can be prevented from traveling backward against the user's intention.

[ Effect of the present application ]

As described above, the walking assist device 10 described in the present embodiment can drive the left and right wheels independently in a forward or backward direction in accordance with the biasing force applied to the left and right grips held by the user, and can travel in the traveling direction desired by the user (forward, backward, right turn, left turn), and can prevent travel to the rear against the user's intention.

The walking assistance device of the present invention is not limited to the configuration, structure, shape, processing procedure, and the like described in the present embodiment, and various changes, additions, and deletions can be made without departing from the scope of the present invention.

In the present embodiment, an example of adjusting the "traveling speed" (the current traveling speed) in the control of the traveling drive unit (electric motor with servo) has been described, but the present invention is not limited to the control of the "speed", and the "torque" may be controlled, or the motor torque may be controlled to adjust the traveling speed.

Instead of the control in the control mode of the "right turn" according to the present embodiment, the control device 40 may control the travel drive units 64L and 64R so as to stop the right drive wheel 60RR, drive the right drive wheel 60RR, and drive the left drive wheel 60RL in the forward direction. Instead of the control in the "left turn" control mode, the control device 40 may control the travel drive units 64L and 64R so as to stop the left drive wheel 60RL and drive the left drive wheel 60RL and the right drive wheel 60RR in the forward direction, respectively. This makes it possible to turn the walking assistance device while advancing forward, and the user can turn the walking assistance device more naturally while walking.

In the present embodiment, an example has been described in which the control device 40 determines, by the acting force detection units 71L, 71R, that an acting force (front acting force/rear acting force) is detected as an acting force when the acting force continues for a predetermined determination time or longer, and neither the front acting force nor the rear acting force is detected when the acting force does not act for the predetermined determination time or longer. Alternatively, the control device 40 may detect an acting force as the acting force when the acting force (the forward acting force and the rearward acting force) equal to or greater than a predetermined acting force determination threshold continues for a predetermined determination time, and may not detect either the forward acting force or the rearward acting force when the acting force is lower than the acting force determination threshold for the predetermined determination time or longer. This can further reduce erroneous detection of the acting force.

Instead of the pressure-sensitive sensor 75 described in the present embodiment, the acting force detection units 71L and 71R may detect the acting force using switches that are turned on when pressed at or above a predetermined pressure. At this time, the control device 40 determines by the acting force detection means 71L, 71R that the acting force is detected when the switch is turned on.

In the present embodiment, an example of control is described in which the walking assistance device 10 is driven so as to advance even when the grip of either the right grip 20R or the left grip 20L is stopped and the grip is in a state of being separated from the hand ("neutral") and a forward acting force acts on the gripped grip, that is, when walking forward with only one hand grip. However, the present invention is not limited to this, and for example, when walking forward while gripping only one of the right grip 20R and the left grip 20L, the control device 40 may control the walking assistance device 10 to move forward for 5 seconds and then stop. Thus, even when the user stops gripping with both hands and controls the walking assistance device 10 to advance by gripping with only one hand, the user can be facilitated to grip with both hands by setting the time limit for forward travel, and can walk more safely.

Although the example of limiting the travel speed in SB700 (travel speed limiting process) in the present embodiment has been described, the travel in the travel direction of the walking assistance device may be limited by the travel direction acceleration in addition to the limitation based on the travel speed, or may be limited by the travel direction acceleration instead of the limitation based on the travel speed. This prevents the walking assistance device from suddenly accelerating in the traveling direction, and the walking assistance device does not separate from the user, so that the user can walk more safely. The travel direction acceleration is obtained based on the travel speed from the travel speed detection means.

In addition, the above (≧ equal to), below (≦), above (>), below (<), and the like may or may not include an equal sign. The numerical values used in the description of the present embodiment are examples, and are not limited to these numerical values.

Claims (7)

1. A walking assistance device is characterized by comprising:

a frame;

a plurality of wheels including a pair of right and left drive wheels provided to the frame;

driving units for traveling, each configured to drive the pair of left and right driving wheels;

a pair of left and right handles provided on the frame and configured to be held by a user;

force detection means which are provided on the pair of left and right handles, respectively, and which detect a forward force acting forward and a rearward force acting rearward in a frame front-rear direction which is a front-rear direction with respect to the frame; and

a control device configured to control the driving unit for traveling,

the control device is connected with the acting force detection unit,

forward control is performed to control the travel drive unit so that the drive wheels are driven in forward directions when the forward acting force is detected on one of the handles and the backward acting force is not detected on the other of the handles,

a backward movement control unit configured to control the driving unit for traveling respectively so that the driving wheels are driven respectively in a backward direction when the backward acting force is detected in one of the grips and the forward acting force is not detected in the other grip,

the rear acting force is detected in the right handle, and when the front acting force is detected in the left handle, the right turning control is performed,

the forward acting force is detected in the right hand grip, and when the backward acting force is detected in the left hand grip, left-turn control is performed,

when the rearward acting force is detected by both the handles when the rearward acting force is not being controlled, the control is stopped for a predetermined stop time, and then the rearward control is performed.

2. The walking assist device of claim 1,

the control device controls the travel drive means so that the right drive wheel is driven in the backward direction and the left drive wheel is driven in the forward direction during the right turn control,

the control device controls the travel drive means so that the right drive wheel is driven in the forward direction and the left drive wheel is driven in the reverse direction during the left turn control.

3. The walking assist device of claim 1,

the control device controls the travel drive means so that the right drive wheel is driven to stop the right drive wheel and the left drive wheel is driven in the forward direction during the right turn control,

the control device controls the travel drive means so that the left drive wheel is driven to stop and the right drive wheel is driven in the forward direction during the left turn control.

4. A walking assistance device according to any one of claims 1 to 3,

the control device performs stop control for controlling the travel drive unit so as to decelerate the travel assist device, respectively, in order to stop the drive wheels, respectively, when neither of the forward acting force and the rearward acting force is detected in both of the handles by the acting force detection unit.

5. A walking aid according to any one of claims 1 to 4,

the walking assistance device is further provided with a traveling speed detection unit,

the travel speed detection means is configured to detect a travel speed that is a speed of the walking assistance device in a travel direction,

the control device obtains a traveling direction acceleration which is an acceleration in the traveling direction based on the traveling speed detected by the traveling speed detection means,

the driving device is configured to drive the driving wheels so that the traveling speeds of the driving wheels become the predetermined speeds when the traveling speeds become equal to or higher than a predetermined speed, or so that the traveling direction accelerations of the driving wheels become the predetermined accelerations when the traveling direction accelerations become equal to or higher than a predetermined acceleration.

6. A walking assistance device according to any one of claims 1 to 5,

the control device controls, by the acting force detecting unit, the operating force of the operating member,

detecting an acting force acting toward the front in the front-rear direction of the frame as the front acting force when the acting force continues for a predetermined determination time or longer,

detecting an urging force acting in the rear direction of the frame as the rear urging force when the urging force continues for the predetermined determination time or longer,

when no force acts in the frame front-rear direction for the predetermined determination time or longer, neither the front force nor the rear force acts.

7. The walking assist device of claim 1,

the walking assistance device further includes a battery serving as a power source for the driving unit for running and the control device.

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