CN110709314B

CN110709314B - Rocker arm bogie mechanism and walking device

Info

Publication number: CN110709314B
Application number: CN201780091262.5A
Authority: CN
Inventors: 吉田基一; 一户広隆; 横山熏
Original assignee: Investment Tianjin Continental Co ltd
Current assignee: Investment Tianjin Continental Co ltd
Priority date: 2017-07-04
Filing date: 2017-07-04
Publication date: 2022-06-21
Anticipated expiration: 2037-07-04
Also published as: WO2019008673A1; CN110709314A

Abstract

The rocker arm bogie mechanism of the present invention is a thin rocker arm bogie mechanism, which includes a center frame, and a pair of rocker arm bogies that are disposed on both sides of the center frame and can independently travel, each of the rocker arm bogies having a rocker arm frame that is pivoted to the center frame and extends substantially in a horizontal direction. The rocker arm bogie mechanism is used as a trolley, and a main body is mounted on a central frame to be used as a traveling device, so that the rocker arm bogie mechanism has strength and breakthrough performance for step difference.

Description

Rocker arm bogie mechanism and walking device

Technical Field

The invention relates to a rocker arm bogie mechanism, in particular to a rocker arm bogie mechanism suitable for a manned walking device.

Background

At present, when a four-wheel electric scooter which is widely used encounters a step section difference, one of four wheels is suspended and cannot contact the ground, so that the four-wheel electric scooter cannot move or overturn. Further, there is a problem that it is difficult to change the route on a narrow road because of the inability to go around on the spot.

On the other hand, in the field of self-propelled vehicles such as robots, a traveling device provided with a rocker arm bogie mechanism is often used to travel on irregular ground having irregularities (for example, patent document 1). The rocker arm bogie mechanism has two links (rocker arm and bogie) flexibly connected to each other, and a wheel unit is connected to the lower end of each link. Patent document 1 discloses an omnidirectional vehicle in which two links of a rocker arm bogie mechanism are rectangular, wheel units are attached to opposite sides of the two links, and six driving wheels are driven in total.

With this structure of the rocker arm bogie mechanism, even when, for example, a wheel of a bogie connected to the front in the traveling direction climbs up a step (convex portion) or falls down a step (concave portion), all the wheels can be kept in contact with the ground by the bending of the rocker arm and the bogie, and the stability when traveling on a step can be ensured.

Patent document 2 describes a wheelchair in which casters are provided in front of and behind a drive wheel, and the rear caster is fixed to a chair portion so that the drive wheel and the front caster can swing with respect to the chair portion. With this structure, it is possible to make the upper and lower step difference or the rotation around the driving wheel.

[ patent document 1] Japanese patent application laid-open No. 2001-253364

[ patent document 2] Japanese patent laid-open No. 2000-24043

Disclosure of Invention

Summary of The Invention

Problems to be solved by the invention

A traveling vehicle using a conventional rocker arm bogie mechanism as described in patent document 1 includes a frame (link) which is located at an intermediate position in the left-right direction and which is a flexible structure. Such a structure is less problematic for an unmanned traveling vehicle, but when a seat portion for carrying a person or the like is fixed to the frame, it is not possible to ensure the horizontality of the seat portion. That is, when a person seated on the seat portion goes over a step, the person is shaken back and forth, and the stability is extremely poor.

In the mechanism described in patent document 2, since the rear caster is fixed to the chair portion, when the rear caster goes over or descends from the step, the impact force is directly transmitted to the chair portion, the sitting feeling is not comfortable, and it is difficult to maintain the horizontality of the seat. A cushion device may be provided in the traveling vehicle (wheelchair) to maintain the ride and the horizontality of the vehicle, but in this case, the height of the seat surface is increased, and the vehicle is not suitable for a traveling vehicle with a limited height. And the increase in height impairs postural stability.

The invention provides a thin rocker arm bogie mechanism with strength and breakthrough to step difference. Further, a novel traveling device is provided which can achieve both riding performance and operability by using such a thin type rocker arm bogie mechanism.

Means for solving the problems

To solve the above problem, the rocker arm bogie mechanism of the present invention has a center frame, and a pair of independently traveling rocker arm bogies are arranged on both sides of the center frame. Further, each of the swing arm trucks has a swing arm frame pivotally provided to the center frame to be rotatable and extending substantially in a horizontal direction.

The traveling vehicle according to the present invention includes a body and a bogie having the above-described rocker bogie mechanism. The body is fixed to the central frame.

ADVANTAGEOUS EFFECTS OF INVENTION

The structure of the pair of rocker arm bogie mechanisms pivoted on both sides of the central frame can keep stable posture for walking when the rocker arm bogie mechanism on one side crosses or goes up and down the step difference, and can keep the horizontality of the central frame when the rocker arm bogie mechanism crosses or goes up and down the step difference. Further, since the rocker frame constituting the rocker bogie mechanism extends in the horizontal direction, the increase in the overall height can be suppressed. Therefore, when the walking device is applied to a manned walking device, stable walking can be ensured.

Other features and effects of the rocker arm bogie mechanism and the traveling vehicle according to the present invention will be described in the following embodiments.

Drawings

Fig. 1 is a perspective view of a rocker arm bogie mechanism of a first embodiment.

Fig. 2 is a top view of the rocker arm bogie mechanism of fig. 1.

Fig. 3 is a side view of the swing arm bogie mechanism of fig. 1.

Fig. 4 is a perspective view of the swing arm frame to which the wheel is fixed.

Fig. 5 is an exploded perspective view of the bogie frame.

Fig. 6(a) and (b) are views showing modified examples of wheels, respectively.

Fig. 7 is a perspective view showing a specific portion (stabilizer portion) of fig. 1.

Fig. 8(a-1) to (g-2) are views for explaining the operation of the rocker arm bogie mechanism of the first embodiment.

Fig. 9(a) is a view showing a rocker arm bogie mechanism according to the second embodiment, and (b) is a view showing a modification.

Fig. 10(a) and (b) are diagrams for explaining the functions of the rocker arm bogie mechanism of the second embodiment.

Fig. 11 is a diagram illustrating a modification of the swing arm bogie mechanism of the second embodiment.

Fig. 12 is a diagram showing an embodiment of the running gear.

Description of the symbols

1: rocker-arm bogie mechanism 100: central frame

115: central bearing

portions

200A, 200B: walking part

210: the rocker arm frame 211: first end part

212: second end portion 213: intermediate section

215: rocker arm bearing portion 216: frame part

217: the frame portion 218: first bogie bearing portion

219: plate-shaped member 220: bogie frame

221: end 222: end part

225: second bogie bearing portion 226: frame part

227: frame portions 229: angular part

310: first wheel (rear wheel) 320: second wheel (Driving wheel)

330: third wheel (front wheel) 335: shaft

400. 480: the stabilizer 410: supporting member

420: the swinging member 430: holding support

440: shaft 450: rod-like member

490: the reinforcing plate 500: main shaft

510: shaft 600: driving source (Motor)

610: mounting portion 611: fixed block

612: the cover block 650: leather belt

700: the support column 710: top board

750: a handle 760: support post

G: flat surface S, S1, S2: difference in level

Detailed Description

First, an embodiment of the rocker arm bogie mechanism of the present invention will be described.

First embodiment

The rocker arm bogie mechanism of the present embodiment includes a center frame and a pair of traveling units symmetrically attached to the center frame. The pair of traveling units each include a rocker frame supported by a shaft and fixed to the center frame, a bogie frame pivoted to one end (first end) of the rocker frame, and first, second, and third wheels pivoted to the other end (second end) of the rocker frame and to both ends of the bogie frame.

Each rocker frame of the pair of traveling units has a frame portion extending in the horizontal direction. That is, each rocker arm frame has two frame portions which are located between the first end portion and the second end portion, respectively, and are bent away from the position pivotally provided to the center frame in the horizontal direction.

The following describes the rocker arm bogie mechanism of the present embodiment with reference to the drawings. In the following description, the moving direction of the rocker arm bogie mechanism by the positive rotation of the drive wheels is referred to as a traveling direction or a front-rear direction, and the horizontal direction orthogonal to the traveling direction is referred to as a left-right direction. The side of the wheel contacting the ground is referred to as a lower side, and the opposite side thereof is referred to as an upper side.

As shown in fig. 1 and 2, the swing arm bogie mechanism 1 of the present embodiment includes a center frame 100, and a pair of traveling

units

200A and 200B attached to both left and right sides of the center frame 100. The left and right traveling

units

200A and 200B are symmetrical in structure to both sides of the center frame 100, and in the following description, the reference numerals used are omitted from the end A, B unless the two and the elements constituting the two are particularly distinguished.

The center frame 100 is formed of a member having a longitudinal direction in a traveling direction, and serves as a main structure of the swing arm bogie mechanism 1 of the present embodiment. A central bearing portion 115 is formed approximately at the center in the longitudinal direction of the central frame 100, and a main shaft 500 for mounting the traveling

portions

200A and 200B is fixed to the central bearing portion 115.

The traveling

units

200A and 200B form the rocker-arm bogie mechanism 1, and each include a rocker frame 210 pivoted to the spindle 500, a bogie frame 220 pivoted to one end (first end) 211 of the rocker frame 210, and three wheels (a first wheel 310, a second wheel 320, and a third wheel 330) pivoted to the other end (second end) 212 of the rocker frame 210 and to both ends 221 and 222 of the bogie frame 220. That is, the swing arm bogie mechanism 1 of the present embodiment is composed of a pair of swing arm bogie mechanisms symmetrical to each other with respect to the center frame 100. Since the rocker frames 210A and 210B of the traveling

units

200A and 200B are respectively pivoted to the center frame 100, they can be independently pivoted. Therefore, only one of the walking parts can climb up or down the step difference.

In addition, when the pair of first wheel 310, second wheel 320, and third wheel 330 is in contact with a flat surface (horizontal surface), the swing arm frames 210A and 210B are substantially parallel to the horizontal surface, that is, are formed in a substantially curved shape in the horizontal surface. That is, as shown in fig. 2 and 3, the polygonal shape formed by connecting the first end portion 211A and the second end portion 212A of the swing arm frame 210A to the portion (referred to as the intermediate portion) 213A connected to the center frame 100, and the polygonal shape formed by connecting the first end portion 211B and the second end portion 212B of the swing arm frame 210B to the intermediate portion 213B are substantially parallel to the flat ground surface. Therefore, the rocker arm bogie mechanism 1 having a low height and stability can be realized.

In the rocker arm bogie mechanism 1 of the present embodiment, the second wheel 320 pivoted to one end of the bogie frame 220 and located at the center of the three wheels is a driving wheel, and the third wheel 330 pivoted to the bogie frame 220 and the first wheel 310 pivoted to the rocker arm frame 210 are driven wheels, the former being a front wheel and the latter being a rear wheel. To this end, the bogie frame 220 is provided with a drive source mounting portion 610 on which a drive source 600 for driving the second wheels 320 as drive wheels, such as a motor, is mounted.

Further, the rocker arm bogie mechanism 1 of the present embodiment is provided with one or more stabilizers 400 between the traveling

portions

200A and 200B. The stabilizer 400 has a function of stabilizing the traveling

units

200A and 200B that are independently pivotable with respect to the center frame 100.

In the following, the details of each part constituting the swing arm bogie mechanism 1 of the present embodiment will be described with reference to fig. 1 to 6, following the outline of the swing arm bogie mechanism.

As shown in fig. 1 and 2, the center frame 100 is a rectangular parallelepiped member having a longitudinal direction in a traveling direction. The length of the member in the longitudinal direction is not limited, but the distance between the front wheel and the rear wheel is almost the same. A central bearing portion 115 is fixed to the center of the center frame 100 in the longitudinal direction, and the central bearing portion 115 is a bearing for pivoting the main shaft 500 of the rocker frames 210A and 210B. Further, on the upper surface of the center frame 100, support members 410 for supporting and fixing the stabilizer 400 are fixed at two positions between the center bearing portion 115 and both ends. The structure of the support member 410 will be described in detail later.

As shown in fig. 4, the rocker arm frame 210 includes, as main components, a rocker arm bearing portion 215, and

frame portions

216 and 217 fixed to both sides (front and rear sides) of the rocker arm bearing portion 215 in the front-rear direction. Further, a rocker-frame-side bogie bearing portion 218, which is coupled to a bogie-frame-side bogie bearing portion described later, is fixed to an end portion of the front frame portion 216 (the first end portion 211 of the rocker frame 210). Here, the bogie bearing portion 218 on the rocker frame side is referred to as a first bogie bearing portion, and the bogie bearing portion 225 on the bogie frame side is referred to as a second bogie bearing portion. Also, the end portion of the frame portion 217 on the rear side (the second end portion 212 of the swing arm frame 210) is provided with a configuration to mount the first wheel 310.

The rocker frames 210A, 210B of the traveling

units

200A, 200B are disposed symmetrically on the center frame 100 so that the

rocker bearings

215A, 215B sandwich the center bearing 115 of the center frame 100, and the main shaft 500 is pivotally provided on the center frame 100 so as to pass through and be fixed to the

bearings

215A, 115, 215B.

The

frame portions

216 and 217 are formed of a cylindrical member and have a two-point bent structure. The cylindrical frame portion 216 is fixed to the rocker bearing portion 215 along a direction in which the axial center thereof is orthogonal to the main shaft 500, is bent diagonally forward in the vicinity of the fixed end portion, and is bent forward (in a direction parallel to the front-rear direction) in the vicinity of the bogie bearing portion 225. Similarly, the frame portion 217 is fixed to the rocker bearing portion 215 along a direction in which the axis of the cylindrical member is orthogonal to the main shaft 500, is bent obliquely rearward in the vicinity of the fixed end portion, and is bent rearward (in a direction parallel to the front-rear direction) in the vicinity of the end portion to which the first wheel 310 is attached. Since the length of frame portion 217 in the front-rear direction is longer than the length of frame portion 216 to which bogie frame 220 is attached, the distance between the two wheels (front wheels 330, drive wheels 320) fixed to the opposite ends of bogie frame 220 and first wheels 310 attached to the ends of frame portion 217 in the front-rear direction is substantially the same.

Due to the shapes of the

frame portions

216 and 217, the first wheels 310 and the bogie frames 220 connected to the swing arm frame 210 are horizontally spaced from each other without increasing the height as shown in fig. 2.

The rocker bearing 215 and the

frame portions

216 and 217 and the frame portion 216 and the bogie bearing 225 can be fixed by conventional fixing means such as screwing, screws (bolts), welding, and the like.

The structure of the end portion of the frame portion 217 to which the first wheel 310 is attached differs depending on the type of the first wheel 310 as a driven wheel, and in the embodiment shown in the figure, an Omni wheel (Omni wheel) structure is shown. That is, the end of the frame 217 is formed of a plate-like member 219, and an omnidirectional plate for supporting and fixing a shaft (omnidirectional shaft 335) of an omnidirectional wheel is fixed to the plate-like member 219. The plate-like member 219 may be formed integrally with the cylindrical member constituting the frame portion 217, or may be formed in another form so as to be integrated with the cylindrical member by a conventional fixing method such as screwing, or welding.

As shown in fig. 5, the bogie frame 220 includes, as main components, a bogie bearing portion 225 (second bogie bearing portion), and

frame portions

226 and 227 fixed to both front and rear sides (front and rear sides) of the bogie bearing portion 225 in the front-rear direction. The bogie frame 220 is pivotally fixed to the rocker arm frame 210 by a shaft 510 (see fig. 1 and 2) that passes through the second bogie bearing portion 225 and the first bogie bearing portion 218 in common.

The front frame portion 226 is a cylindrical member, and a structure for attaching a third wheel (front wheel) 330 is provided at an end portion 221 thereof. This structure can take various structures corresponding to the wheel to be mounted, similarly to the structure of the end portion of the frame portion 217 of the swing arm frame 210, and here is constituted by the horn-shaped member 229 for fixing the omnidirectional wheel. The rear frame portion 227 is a cylindrical member having a bent portion formed therein, and includes a horizontal portion 227a extending in a direction orthogonal to the shaft 510 from the second bogie bearing portion 225 and a bent portion 227b bent upward. A mounting portion 610 is provided at the bent portion 227b, and the second wheel 320 as a driving wheel and the driving source 600 thereof are mounted on the mounting portion 610.

The rotary shaft of the second wheel 320 can be fixed to a rotor of a drive source 600, such as a motor, directly or via a power transmission mechanism. The mounting portion 610 is not particularly limited as long as it can support and fix the second wheel 320 integrally formed with the drive source 600 and can be fixed to the frame portion 227 as described above, and is fixed by sandwiching a part of the motor by a fixing block 611 fixed to the frame portion 227 and a cover block 612 detachably fixed to the fixing block. When the driving source 600 is a motor, the driving source 600 is connected to a power supply not shown, and includes a switch for turning on or off the motor.

In the present embodiment, the first wheel 310 and the third wheel 330 are driven wheels driven by driving wheels, and are omnidirectional wheels capable of rotating in all directions. An omni-directional wheel is a conventional structure having a plurality of rotating bodies installed along the circumference of a disk-shaped wheel and rotating with the circumferential direction as an axis, and the disk can be of a one-layer or multi-layer structure. In the example shown in the figure, two layers of disks are used, and the rotating bodies are overlapped on the circumferences of the disks in a staggered manner. The traveling device can obtain excellent space utilization and linear stability by using the omnidirectional wheels. However, the driven wheels are not limited to omnidirectional wheels, and caster wheels and the like can be used.

Although not shown in the drawings, the present invention may be provided with a brake or a stopper for mechanically stopping the rotation of the disc.

In addition, although only the central wheel (the second wheel 320) of the left and right three wheels is referred to as a driving wheel, all the wheels may be referred to as driving wheels, or the central wheel may be referred to as a driving wheel together with either the front wheel or the rear wheel. In the case where the front wheel is not a driving wheel, the step is more difficult to cross as the step approaches the radius of the wheel, and in the case of a driving wheel, even the step approaching the radius of the wheel can easily cross. The front wheel may be a driving wheel, a caster wheel, or an in-wheel motor shown in fig. 6 (a). Further, since the front wheel 330 is disposed on the same line as the second wheel (drive wheel) 320 via the bogie frame 220, the drive wheel may be formed by connecting a motor 600 of the drive wheel with a belt 650 or a chain as shown in fig. 6 (b).

Next, the stabilizer 400 will be described with reference to fig. 7.

The stabilizer 400 is a mechanism for preventing the frames of the left and right traveling

units

200A and 200B, which are independently operable, from being twisted and for ensuring the stability of the operation, and as shown in fig. 7, the stabilizer 400 is mainly composed of a bar-shaped member 450 which is bridged between the two traveling

units

200A and 200B and a mechanism for supporting and fixing the bar-shaped member 450. In the embodiment shown in fig. 7, the stabilizer 400 is provided at two locations between the

first end portions

211A and 211B and between the

second end portions

212A and 212B of the rocker arm frames 210A and 210B, but the basic structure is the same, and the following description is common to both unless otherwise specified.

The rod-shaped member 450 is a member (torque rod) formed of a metal rod such as a steel material, and has a diameter that varies depending on the scale or weight of the rocker arm bogie mechanism 1 or the traveling vehicle, but is rigid enough to cope with the deflection that occurs when the height difference occurs between the left and right wheels. A block (swinging member) 420 is fixed to the longitudinal center of the rod-like member 450.

The support mechanism for the rod-like member 450 is constituted by a support member (pivot member) 410 on the center frame 100 side and a support member (430) on the rocker frame 210 side.

The support member 410 on the center frame 100 side is a member having a cross section of 21274H shape, which is composed of a bottom surface, an upper surface, and a vertical surface connecting the bottom surface and the upper surface, and the bottom surface is fixed to the upper surface of the center frame 100 by bolts or the like. The swing member 420 fixed to the center of the rod member 450 is pivoted inside the vertical surface of the support member 410 by a shaft 440. The direction of the shaft 440, which pivots the swing member 420, is orthogonal to the vertical plane, so that the swing member 420 can rotate on a plane parallel to the vertical plane. Here, the height of the swing member 420 (the dimension in the direction perpendicular to the rod-shaped member 450) is designed to be slightly smaller than the distance between the top surface and the bottom surface of the support member 410, so that the rotation of the swing member 420 is restricted to a predetermined angular range, for example, ± 15 degrees. Therefore, the swing member 420 is swung within a limited angular range, and vibration generated when a difference in level occurs between the left and right wheels can be absorbed without affecting the center frame 100.

On the other hand, as shown in fig. 7, the holding brackets 430 as the support fixing members for the rod-like members 450 are fixed to the first end portions 211 and the second end portions 212 of the left and right rocker arm frames 210A, 210B, and the rod-like members 450 are slidably fixed to the holding brackets 430. The holding bracket 430 has an outer shape in which two members having an L-shaped cross section are combined in a vertically opposite and opposing manner, and a through hole is formed in an upper vertical surface thereof, and the rod-shaped member 450 is inserted through the through hole and supported and fixed thereto. With this supporting and fixing structure, even when the rod-shaped member 450 is bent due to a difference in height between the left and right wheels, the width between the left and right wheels can be maintained by the end of the rod-shaped member 450 being displaced in the direction indicated by the arrow in the figure.

As described above, the rocker arm bogie mechanism 1 of the present embodiment is fixed so that the pair of traveling

portions

200A and 200B disposed so as to sandwich the center frame 100 can rotate independently of each other with respect to the center frame 100. Therefore, if a part (or all) of the wheels of one traveling unit have a step difference between the upper and lower steps, the frame may be twisted or the verticality of the wheels may not be maintained, and the traveling posture may be unstable. In contrast, by providing the stabilizer 400 having the above-described structure, the pair of traveling

units

200A and 200B (wheels) that can independently rotate are prevented from twisting, and stability during traveling is maintained. Further, the torsion bar can be used as the stabilizer 400, and the effects of preventing twisting and maintaining stability can be obtained by a simple and lightweight structure without using a heavy mechanism such as a differential gear.

In the embodiment shown in fig. 7, the stabilizers 400 are provided at two locations between both end portions of the swing arm frame 210, but the positions where the stabilizers 400 are provided or the number of stabilizers 400 is not limited to this embodiment.

Following the above-described configuration of the swing arm bogie mechanism 1, the operation of the swing arm bogie mechanism 1 according to the present embodiment will be described below with reference to fig. 8.

Fig. 8(a-1) to (g-1) are side views (side views) of the state of the vertical step S of the swing arm bogie mechanism 1, and the swing arm bogie mechanism 1 travels forward with the third wheel 330 as the front wheel. Fig. 8(a-2) to (g-2) are diagrams (front views) of states in which one of the pair of traveling parts of the rocker bogie mechanism 1 climbs up or descends by the step S corresponding to (a-1) to (g-1) as viewed from the front (front side).

Initially, description will be made of a case where the rocker arm bogie mechanism 1 climbs the level difference S1 higher than the flat surface G while traveling, with reference to fig. 8(a-1) to (c-1).

First, the drive source 600 drives the drive wheels 320, and thus the rocker bogie mechanism 1 travels forward as indicated by arrows in the figure. In a state where the swing arm bogie mechanism 1 travels on the flat surface G (fig. 8(a-1), (a-2)), each pair of the third wheel (front wheel) 330, the second wheel (driving wheel) 320, and the first wheel (rear wheel) 310 contacts the flat surface G. In this state, the center frame 100 and the swing arm frame 210 are kept horizontal.

As shown in fig. 8(b-1), when the front wheel 330 hits the step S1 during traveling, the front wheel 330 climbs the step S1 due to the propelling force of the driving wheel. At this time, since the truck frame 220 rotates clockwise about the truck shaft 510 as an axis with respect to the swing arm frame 210, the driving wheel 320 can maintain a state of contact with the flat surface G even if the front wheel 330 is lifted. In addition, from the perspective of the center frame 100, since the difference in height between the front wheels 330 and the drive wheels 320 is absorbed by the rotation of the bogie frame 220, the center frame 100 can be kept horizontal.

As shown in fig. 8(c-1), the swing arm bogie mechanism 1 further travels forward, and when the driving wheel 320 climbs the step S1 behind the front wheel 330, the bogie frame 220 rotates counterclockwise, and therefore, both the front wheel 330 and the driving wheel 320 can contact the step S1. At this time, although a level difference is generated between the truck axle 510 and the axle of the rear wheel 310, the swing arm frame 210 rotates clockwise about the main axle 500 with respect to the center frame 100, so that the rear wheel 310 can maintain a state of contact with the flat surface G even if the driving wheel 320 is lifted. Further, since the difference in height between the truck axle 510 and the axle of the rear wheel 310 is absorbed by the rotation of the swing arm frame 210, the center frame 100 can be kept horizontal.

Next, referring to fig. 8(d-1), a case will be described in which the rocker arm bogie mechanism 1 is going to go over a convex step S, the width of which is relatively narrower than the interval between the front wheel 330 and the drive wheel 320. In this case, the front wheel 330 having the stepped portion S1 climbed as illustrated in fig. 8(b-1), and when the driving wheel 320 climbs the stepped portion S1 (convex portion), the front wheel descends to the flat surface G located lower than the convex portion. At this time, the bogie frame 220 is freely rotated counterclockwise, so that the front wheel 330 can be brought into contact with the flat surface G without being affected by the elevation of the driving wheel 320. Even if the driving wheel 320 is lifted, the rear wheel 310 can be kept in contact with the flat surface G by the free clockwise rotation of the swing arm frame 210. The difference in wheel height generated in any state is absorbed by the rotation of the bogie frame 220 and the swing arm frame 210, so that the center frame 100 can be maintained horizontally.

Fig. 8(e-1) to 8(G-1) illustrate the state in which the rocker arm bogie mechanism 1 is lowered to the step S2 having a height lower than the flat surface G when traveling on the flat surface G. In such a case, the center frame 100 can climb down or up the level difference while maintaining the horizontality, as in the case of walking on the convex level difference S1.

That is, when the front wheel 330 approaches the step S2 from the flat surface G while the rocker arm bogie mechanism 1 is traveling on the flat surface G, the front wheel 330 can freely rotate counterclockwise via the bogie frame 220, and can descend from the step S2 without floating and contact a low ground surface (fig. 8 (e-1)).

Then, when the rocker arm bogie mechanism 1 travels further forward and the drive wheel 320 descends from the step S2 after the front wheel 330, the front wheel 330 and the drive wheel 320 can descend from the step S2 without leaving the ground and contact the ground by the clockwise rotation of the bogie frame 220. At this time, the rear wheel 310 can maintain a state of contact with the flat surface G by the self-centering counterclockwise rotation of the swing arm frame 210. (FIG. 8 (f-1)).

In addition, as shown in fig. 8(g-1), when the vehicle travels in a concave portion where the interval of the step S is narrower than the width between the wheels, the bogie frame 220 rotates according to the difference in height between the front wheels 330 and the driving wheels 320, and the swing arm frame 210 rotates according to the difference in height between the driving wheels 320 and the rear wheels 310, and the wheels can travel while being maintained in contact with the ground without floating from the ground, as in the case described in fig. 8(b-1) and 8 (f-1). Therefore, the power from the drive source 600 can be efficiently transmitted to all the wheels.

The operation of the step difference between the upper and lower wheels on both sides of the traveling unit 200 is described with reference to fig. 8(a-1) to (g-1). In the present embodiment, the left and right traveling

units

200A and 200B of the rocker arm bogie mechanism 1 of the present invention are basically provided independently of the center frame 100, and therefore, even when the wheels of only one of the traveling units 200 have a step difference in the vertical direction, the operation of the bogie frame 220 and the rocker arm frame 210 is the same as the above-described operation. In this case, however, the stabilizer 400 maintains stability while walking.

Hereinafter, the operation of the stabilizer 400 during traveling will be described with reference to the drawings (a-2) to (g-2) on the right side of fig. 8. The right side of the figure is described as a traveling unit 200A, and the left side is described as a traveling unit 200B. As shown in fig. 8(B-1) and (B-2), when only the front wheel 330A of the traveling unit 200A climbs up the step S, the traveling

units

200A and 200B independently operate, respectively, and thus can travel without hindrance.

Then, as shown in fig. 8(c-1) and (c-2), when the driving wheel 320A also ascends up to the step S, the holding bracket 430A fixed to the first end 211A of the swing arm frame 210A is lifted up relative to the left traveling unit 200B. By the operation of the holding bracket 430A, one end of the rod member 450 is pulled upward, and accordingly, the swing member 420 is tilted to a certain extent like a pendulum, and the rod member 450 is deflected, thereby absorbing the difference in height between the left and right. Therefore, the center frame 100 can maintain the horizontal performance without being affected by the horizontal height difference. Further, since the rod-shaped member 450 generates a force for pressing the driving wheel 320A down to contact the ground due to its rigidity, it is possible to prevent the driving wheel 320A from being unstable in posture due to excessive rotation or lateral inclination of the swing arm frame 210A caused by an impact generated when the driving wheel 320A is lifted up.

On the other hand, as shown in fig. 8(e-1) to 8(f-2), when the front wheel 330 and the drive wheel 320 of the traveling unit 200A are lowered to the step S2 of the concave portion, the position of the holding bracket 430A fixed to the first end portion 211A of the rocker frame 210A is relatively lowered with respect to the position of the holding bracket 430B of the left traveling unit 200B, and the rod-shaped member 450 is pulled downward. Therefore, the swing member 420 is tilted to a certain degree like a pendulum, and the rod member 450 is deflected downward, thereby absorbing the height difference between the left and right. Therefore, the center frame 100 can maintain the horizontal performance without being affected by the horizontal height difference. Further, the rod-shaped member 450 can prevent the posture of the rocker arm frame 210A from becoming unstable due to excessive rotation or lateral tilting.

While the rocker arm bogie mechanism of the present embodiment has been described above with reference to the drawings, the rocker arm bogie mechanism of the present invention is characterized by a structure in which the traveling units formed by the rocker arm bogie mechanism are pivotally provided on both sides of the center frame via the rocker arm frames, but the present invention is not limited to the above-described embodiment, and it is possible to eliminate or add unnecessary elements, or to change the external shape of the constituent elements. Several modifications are listed below.

Second embodiment

The rocker arm bogie mechanism of the present embodiment is characterized in that the rocker arm bogie mechanism of the first embodiment is further provided with means for improving the resistance to torsional stress applied to the frame by a load. The other configurations are the same as those of the first embodiment. The following describes the rocker arm bogie mechanism according to the present embodiment with reference to fig. 9 and 10. Fig. 9 is a plan view of the swing arm bogie mechanism according to the present embodiment, and fig. 10 is a view illustrating the operation thereof. In the drawings referred to in the present embodiment, the same elements as those of the swing arm bogie mechanism of the first embodiment are denoted by the same reference numerals, and redundant description thereof is omitted.

In the present embodiment, as shown in fig. 9(a) and 10(b), the stabilizer 480 is disposed at the front end of the frame portion 227 of the bogie frame 220, which is a mounting portion for the motor. In the example shown in the figure, the front end of the frame portion 227 is further bent, and the stabilizer 480 is attached by this configuration. The stabilizer 480 can be a rod-shaped member (tension rod) similar to the stabilizers 400(450) disposed at the front and rear of the center. In the figure, the supporting member of the stabilizer 480 is omitted, but the same structure as the stabilizer 400 arranged in the front and rear can be adopted.

Alternatively, as shown in fig. 9(b), the reinforcing plate 490 may be fixed to the bogie frame 220 supporting and fixing the motor 600, and the stabilizer 480 as a rod-shaped member may be supported and fixed by the left and right reinforcing plates 490.

In the swing arm bogie mechanism 1 of the first embodiment, since the swing arm frame 210 and the bogie frame 220 are disposed horizontally with respect to the center frame 100, a load applied to the center frame 100 is applied to the outermost wheels as shown in fig. 10 (a). In particular, since the load applied to the second wheel (drive wheel) 320 positioned at the center is the largest, a torsional stress due to the load is generated in the frame (the frame portion 216 of the swing arm frame 210 and the frame portion 227 of the bogie frame 220) to which the drive wheel 320 and the motor 600 are connected. Therefore, the upper portion of the motor attached to the frame portion 227 is easily tilted inward, and the driving wheel 320 is easily splayed.

In contrast, in the present embodiment, when the stabilizer 480 is disposed on the center frame 100, as shown in fig. 10(b), when a load is applied to the center frame 100 and the stabilizer 480 is deflected downward by the displacement thereof, a force directed outward is generated at the front end of the bogie frame 220 (frame portion 227) supporting and fixing both ends thereof. With this arrangement, the wheel can be prevented from splaying against the force of the motor which is directed inward.

As a means for improving the resistance to the torsional stress generated by the load applied to the center frame 100, means such as replacing the stabilizer 480, increasing the diameter and thickness of the stabilizer 480 and the frame itself, and adding support reinforcement can be adopted.

For example, in addition to the reinforcing plate 490 shown in fig. 9(b), as shown in fig. 11, a diagonal bar reinforcing frame, a reinforcing plate member 219, or the like may be added between the position pivotally provided on the center frame 100 and each of the

end portions

211, 212. In this example, the reinforcing plate-like member 219 is fixed to the rocker bearing portion 215 and the first bogie bearing portion 218 of the rocker frame 210, and reinforces a portion of the rocker frame 210 that is most likely to receive a load. Further, the second bogie bearing portion 225 and the

frame portions

226 and 227 fixed to both sides thereof can be reinforced by the reinforcing plate.

According to the present embodiment, the structural problem caused by mounting the rocker frame 210 and the bogie frame 220 in the horizontal direction on the center frame 100 is solved, and the rocker bogie mechanism 1 having a strong structure is realized.

Modification examples

Although the embodiment of the swing arm bogie mechanism 1 according to the present invention has been described above with reference to the drawings, the shape of each frame constituting the swing arm bogie mechanism 1 may be different from the above-described embodiment, and a member for reinforcing the strength may be added as appropriate. For example, in the embodiment, the swing arm frame 210 includes two

frame portions

216 and 217 which are bent obliquely forward and obliquely rearward, but a circular arc frame, a frame which is bent perpendicularly to the traveling direction, or the like may be employed.

The truck frame 220 can also change the distance between the front wheels and the drive wheels by appropriately changing the bending direction.

Embodiment of running gear

The rocker arm bogie mechanism 1 of the present invention can be applied to various traveling devices such as unmanned self-propelled vehicles (robots), manned electric vehicles, wheelchairs, and the like, and is particularly suitable for use in a traveling device for people to ride on, and has a feature of a mechanism capable of maintaining the horizontality of the center frame 100 and maintaining a low and flat stable posture.

In the present embodiment, an electric scooter (electric wheelchair) in which a chair or an operation handle on which a person sits is attached to the rocker bogie mechanism 1 will be described as an example of a traveling device. The electric wheelchair is specified by JIS in accordance with specifications (full length: 1200mm, full width: 700mm, full height: 1090mm, and step height: 40mm), and the size of the rocker bogie mechanism 1 and the size of the chair mounted thereon conform to the specifications.

From the viewpoint of structural strength and smoothness of operation, it is preferable to provide the shaft (center) of the drive wheel 320 at a position on the bottom surface (lower end) of each frame (the rocker frame 210 and the bogie frame 220) of the rocker-bogie mechanism 1, and a range from the position of the shaft to the left and right of the frame thickness is acceptable. If the lower end of the frame is lower than the axle of the wheel, it is difficult to get over a step higher than the radius of the wheel, and the lower end easily touches the step. Specifically, the standard footpath has a height of 200mm, the step of the ramp when climbing up the footpath from the lane is about 50mm, and the height near the center of the ramp is about 100 mm. The height of the frame is preferably about 120 mm. On the other hand, if the lower end of the frame is positioned higher than the axis of the wheel, a load from above is applied to the upper side of the driving wheel 320, and a torsional stress is applied to the inner side of the frame. In addition, the clearance between the load on the center frame 100 and the swing arm frame 210 or the bogie frame 220 is narrowed, so that the tolerance of the frame in rotation is also narrowed when the step difference is crossed.

Fig. 12 shows an example of the electric scooter of the present embodiment. As shown, a column 700 of a chair (not shown) is fixed to a position slightly behind the central bearing portion 115 of the central frame 100 of the rocker arm bogie mechanism 1, and a top plate 710 for fixing the chair to the upper end of the column 700 is rotatably fixed to the column 700 which rotates as an axis. A handle 750 and a support 760 thereof are fixed to the front end of the center frame 100. An operation button for operating the traveling device may be provided near the handle 750. The operation button may be, for example, a switch button of the driving source, a backward button for rotating the driving wheel in the reverse direction, a button for changing the traveling speed, a swivel button, or a switch-on/off button in the case where the traveling device includes a lamp. In addition, a vertical movement mechanism capable of changing the height of the top plate 710 to which the chair is fixed may be provided, and in this case, the operation button may include an operation button of the vertical movement mechanism of the top plate 710.

In this case, the driving source 600 for driving the driving wheel 320 is provided with a control device, and the driving wheel 320 is controlled by operating the buttons. For example, when the reverse button is operated, the control device will reverse the rotation of the drive wheel. Therefore, the traveling device moves rearward in the traveling direction. When the swing button is operated, one of the left and right drive wheels is rotated in a forward direction, and the other is rotated in a reverse direction by the same rotation amount as the forward rotation. Therefore, it is possible to spin on the spot.

The operation of the handle 750 can be transmitted to the driving wheel 320 by an electric signal or a mechanical transmission mechanism. In the case of using an electric signal, the rotation amount of the left and

right driving wheels

320A and 320B is changed by detecting the output of the sensor for handle operation, and thus the left and right driving wheels can be moved in the left or right direction. For example, when the handle 750 is rotated to the left, an electric signal generated according to the rotation amount is transmitted to the control device of the driving source 600, so that the rotation amount of the right driving wheel is relatively increased.

The traveling device according to the present embodiment can easily climb over or descend a step difference while maintaining the stability of the posture by the structure of the traveling unit including a pair of rocker bogie mechanisms pivotally provided on both sides of the center frame. Further, the center frame to which the chair on which a person sits is fixed maintains two good horizontalities, so that it is possible to reduce the rocking and obtain a comfortable sitting feeling.

Further, although it is preferable that the seat surface on which a person sits is fixed to the center frame, a conventional buffer mechanism such as a spring, a backrest portion, an elbow rest, a footrest, and the like for protecting the seat surface and ensuring a sitting feeling and stability during sitting may be provided between the center frame and the seat surface, which will not be described in detail.

Possibility of industrial utilization

The invention provides a novel rocker arm bogie mechanism and a traveling device, which can ensure the stability and the horizontality when the novel rocker arm bogie mechanism travels on uneven ground.

Claims

1. A rocker arm bogie mechanism comprising:

a center frame and a pair of traveling parts symmetrically mounted on the center frame;

the pair of traveling units each include:

a rocker arm frame which is pivoted on the central frame and is parallel to the horizontal plane;

a bogie frame pivotally mounted to a first end of the rocker frame; and

a first wheel, a second wheel and a third wheel which are respectively pivoted at the second end part of the rocker arm frame and the two end parts of the bogie frame;

each rocker frame of the pair of traveling units has two frame portions located between the first end portions and the second end portions, respectively, and the portions of the two frame portions pivoted to the center frame are bent so as to be separated in the horizontal direction; a stabilizer formed of a rod-shaped member is provided between the pair of traveling units.

2. The rocker arm bogie mechanism according to claim 1, wherein the center frame includes a pivot member for pivoting the rod-shaped member, and the pair of traveling units each include a support member for slidably supporting and fixing the rod-shaped member.

3. The swing arm bogie mechanism according to claim 1, wherein the second wheel is positioned between the first wheel and the third wheel along the traveling direction, and the stabilizer is provided between frame portions of the bogie frame to which the second wheel is pivoted of the pair of traveling portions.

4. The swing arm bogie as claimed in claim 1, wherein each of the second wheels of the pair of traveling units is a drive wheel independent from each other and is located between the first wheel and the third wheel.

5. The swing arm bogie mechanism according to claim 4, wherein at least one of the first wheel and the third wheel is a driven wheel that is rotatable in all directions.

6. A traveling device comprising a body and a carriage, wherein the carriage comprises the swing arm bogie mechanism according to any one of claims 1 to 5.

7. The running gear according to claim 6, wherein the body is fixed to a center frame of the swing arm bogie mechanism.

8. A traveling device provided with a plurality of rocker arm bogie mechanisms, the rocker arm bogie mechanisms comprising: a rocker arm frame; a bogie frame pivoted to one end of the rocker arm frame; and a first wheel, a second wheel and a third wheel respectively pivoted to the other end of the swing arm frame and the two ends of the bogie frame; it is characterized in that: a center frame provided in the center in the lateral direction orthogonal to the traveling direction, and the rocker frames of the rocker bogie mechanism being pivotally provided on both sides in the lateral direction of the center frame; each rocker arm frame is parallel to the horizontal plane and has two frame portions that are bent away from each other in the horizontal direction from a position pivotally attached to the center frame.