Personal mobility

Abstract

This invention provides a personal mobility device that is easy to lift from the front and less prone to damage to the left and right arms and their surrounding components in the event of a collision with an obstacle. [Solution] The personal mobility device comprises a left arm supporting the left front wheel and a right arm supporting the right front wheel, and a bar spanning in front of the left arm and the right arm, wherein the bar is made of a pipe material having ends attached to the left arm or the right arm and an intermediate portion positioned in front of each end, and the thickness of each end of the pipe material is greater than the thickness of the intermediate portion.

Description

Technical Field

[0001] The present invention relates to personal mobility.

Background Art

[0002] As an example of personal mobility, Patent Document 1 discloses a so-called senior car. In front of the vehicle body frame constituting this senior car, a bar bent in a U shape is provided. This bar is used, for example, to lift the front part of the vehicle body when the front wheels of the senior car come off the road into a side ditch.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The bar as described above may be attached to the left and right arms that support the left and right front wheels instead of the vehicle body frame. The bar is designed to withstand the load when lifting the front part of the vehicle body. However, when the front part of the vehicle body collides with an obstacle, the load acting on the bar may cause excessive deformation of the left and right arms. In addition, various sensors such as a steering angle sensor may be provided in the front part of the vehicle body. If various sensors necessary for driving are damaged due to a collision, there is a risk of the vehicle becoming inoperable.

[0005] One object of the present invention is to provide a personal mobility that is easy to lift the front part and is less likely to cause damage to the left and right arms and the members in the vicinity thereof when colliding with an obstacle.

Means for Solving the Problems

[0006] A personal mobility device according to one aspect of the present invention comprises a left arm supporting the left front wheel and a right arm supporting the right front wheel, and a bar spanning in front of the left arm and the right arm. The bar is made of a pipe material having ends attached to the left arm or the right arm and an intermediate portion positioned in front of each end. The thickness of each end of the pipe material is greater than the thickness of the intermediate portion.

[0007] In this specification, "personal mobility" includes all small mobile vehicles equipped with an electric motor as a power source and capable of traveling at speeds considered to be those of a pedestrian. For example, standard electric wheelchairs, simple electric wheelchairs, and handlebar-type electric wheelchairs are all included in "personal mobility." Simple electric wheelchairs include both switchable types that can switch between electric and manual powered driving, and assist types that can use electric power to assist human driving. [Effects of the Invention]

[0008] According to the personal mobility device described above, the bar spanning the left and right arms can be used to lift the front of the vehicle. By making the thickness of each end of the pipe material thicker than the thickness of the middle section, the middle section is relatively thinner compared to the ends. When the personal mobility device collides with an obstacle, the deformation of the middle section makes it easier to absorb the impact of the collision. The impact absorption by the middle section can reduce damage to the left and right arms and nearby components. The relative thickness of each end of the bar compared to the middle section increases the mounting strength of the bar to both arms and reduces buckling of the ends of the bar and deformation of both arms. In particular, reducing buckling of the ends of the bar and deformation that causes the tips of both arms to spread apart can reduce the risk of obstacles coming into contact with and damaging various sensors and other components located near both arms. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic perspective view showing the front of the personal mobility device according to this embodiment. [Figure 2]Figure 2 is a schematic perspective view showing the configuration near the arm in Figure 1. [Figure 3] Figure 3 is a partial longitudinal cross-sectional view of the arm shown in Figure 2. [Modes for carrying out the invention]

[0010] Specific examples of personal mobility according to the embodiments of the present invention will be described with reference to the drawings. Hereinafter, "personal mobility" may be simply referred to as "vehicle". In each figure, the same or corresponding parts are denoted by the same reference numerals. The sizes and proportions of the components shown in each figure are represented for the purpose of clarifying the explanation and do not necessarily represent the actual dimensions and proportions. In the figures, "FR" indicates the front of the vehicle, "RR" indicates the rear of the vehicle, "LH" indicates the left side of the vehicle, "RH" indicates the right side of the vehicle, "UP" indicates the top of the vehicle, and "LWR" indicates the bottom of the vehicle. In the following description, the direction of each component will be described based on the direction of the vehicle described above.

[0011] <Personal Mobility> The personal mobility device 1 according to the embodiment will be described with reference to Figures 1 to 3. The personal mobility device 1 of the embodiment is a single-seater electric vehicle. The personal mobility device 1 shown in Figure 1 is a handlebar-type electric wheelchair (mobility scooter). Handlebar-type electric wheelchairs are sometimes called senior scooters.

[0012] One of the features of the vehicle 1 of this embodiment is the structure of the bar 90 attached to the left arm 80L, which supports the left front wheel 20L, and the right arm 80R, which supports the right front wheel 20R. Specifically, the bar 90 is made of pipe material with different thicknesses at both ends, consisting of the left end 90L and the right end 90R, and in the middle section 90M. First, an overview of the vehicle 1 and the main components of the front of the vehicle 1 will be described, and then the details of the bar 90 will be described. In the following description, when the left arm 80L and the right arm 80R are not distinguished, they will simply be referred to as arm 80.

[0013] Vehicle Overview The outline of Vehicle 1 will be explained based on Figure 1. Figure 1 shows only the front of Vehicle 1. However, even in the front of Vehicle 1, exterior members such as covers and members unrelated to the configuration of the invention are removed, and the rear of Vehicle 1 is not shown.

[0014] As shown in Figure 1, Vehicle 1 comprises a frame 10, left and right front wheels 20, and a handle 30. The rear of Vehicle 1 further comprises a seat (not shown), left and right rear wheels, and a motor. Vehicle 1 is a four-wheeled vehicle. The occupant sits in the seat and operates the handle 30. Vehicle 1 is driven by the motor driving the rear wheels. The motor is powered by electricity supplied from a battery. The battery is detachably housed in a battery holder 13. The battery holder 13 is fixed to the rear of the steering column 12. This Vehicle 1 has a maximum speed of, for example, 6 km / h.

[0015] ≪Main components of the front of the vehicle≫ The frame 10 forms the skeleton of the vehicle 1. The frame 10 comprises a main frame 11 and a steering column 12. In this example, the main frame 11 is composed of a pair of pipe members that extend side by side from the front to the rear of the vehicle 1. The front end of the main frame 11 is connected to the steering column 12.

[0016] The steering column 12 supports a steering wheel 30 that steers the front wheels 20. The steering column 12 extends generally vertically so as to intersect with the main frame 11. The steering column 12 is inclined such that its lower end is located forward of its upper end. A steering shaft (not shown) is rotatably inserted through the steering column 12. The steering wheel 30 is attached to the upper end of the steering shaft. The steering shaft transmits the rotational operation of the steering wheel 30 to the front wheels 20.

[0017] A plate-shaped oscillating arm (not shown) is attached to the lower end of the steering shaft. The oscillating arm is a component that transmits the rotation of the steering shaft as the oscillation of the tie rod 50. The lower end of the steering shaft is connected to the front end of the oscillating arm. The end of each tie rod 50 that is closer to the steering shaft is connected to the rear end of the oscillating arm. When the steering shaft is rotated, the rear end of the oscillating arm oscillates from side to side. Each tie rod 50 also oscillates in conjunction with this oscillation of the oscillating arm. The left and right ends of the oscillated tie rods 50 are attached to the knuckle arms of the steering knuckle 60. The steering knuckle 60 is composed of a U-shaped bent plate. As shown in Figure 2, this plate has an upper plate 61, a lower plate 62, and a middle plate 63. The upper plate 61 and the lower plate 62 are connected by the middle plate 63. The upper plate 61 extends further back than the lower plate 62 and constitutes the knuckle arm. A kingpin 65 is positioned between the upper plate 61 and the lower plate 62. A cylindrical portion 66 is positioned on the outer circumference of the kingpin 65. The ends of the left arm 80L and the right arm 80R, which will be described later, are connected to this cylindrical portion 66. A spindle 67 passes through the middle plate 63. The spindle 67 protrudes from the middle plate 63 toward the outside of the vehicle 1. A hub is attached to this spindle 67 via a bearing (not shown). Furthermore, wheels (not shown) that make up each front wheel 20 are attached to the hub.

[0018] A steering angle sensor 45 is provided near the lower end of the steering shaft. The steering angle sensor 45 is attached to the front of the vehicle 1 via a bracket (not shown). A gear 40 is provided at the lower end of the steering shaft. The gear 40 transmits the rotation of the steering shaft to the steering angle sensor 45. The detection result of the steering angle sensor 45 is used to control the driving of the vehicle 1.

[0019] A connecting plate (not shown) is bridged between the main frame 11 and the lower end of the steering column 12. An arm support 70 shown in FIG. 2 is fixed to the lower part of this connecting plate. The arm support 70 is composed of a plate bent in a U shape. This plate has a front plate 71, a rear plate 72, and a middle plate 73. The middle plate 73 connects the front plate 71 and the rear plate 72. A rotating shaft 74 is bridged between the front plate 71 and the rear plate 72. A rotating cylinder (not shown) is provided on the outer periphery of the rotating shaft 74. The base ends of the left arm 80L and the right arm 80R are fixed to the outer peripheral surface of the rotating cylinder. That is, the left arm 80L and the right arm 80R are swung so that the tip of each of the left arm 80L or the right arm 80R moves up and down around the rotating shaft 74. A cylindrical elastic member 80E is attached to the upper part of each of the left arm 80L and the right arm 80R. The elastic member 80E buffers the swing when the left arm 80L and the right arm 80R are swung as the left front wheel 20L and the right front wheel 20R move up and down. Also, the base end of the arm 80 is located above the tip of the arm 80. That is, each arm 80 extends obliquely downward from the base end of the arm 80. The tip of the arm 80 is arranged in front of the base end of the arm 80. That is, each arm 80 extends so as to spread left and right obliquely forward from the base end.

[0020] <<Bar>> In front of the left arm 80L and the right arm 80R, a bar 90 is spanned. The bar 90 may be directly connected to the left arm 80L and the right arm 80R, or may be indirectly connected via other members. In this example, the bar 90 is attached to the left arm 80L and the right arm 80R via brackets 100. The brackets 100 are formed by bending a metal plate. These brackets 100 are welded so as to project forward from the lower part of each of the left arm 80L and the right arm 80R. The mounting position of each bracket 100 along the axis direction on the arm 80 is approximately the middle position of each arm 80. Bolt holes are provided in the brackets 100.

[0021] The bar 90 is composed of a pipe material bent in a U shape. The bar 90 in this example is composed of a round pipe material. This bar 90 includes a left end portion 90L, a right end portion 90R, and an intermediate portion 90M. All of the left end portion 90L, the right end portion 90R, and the intermediate portion 90M are arranged at a height that does not interfere with the road surface. The left end portion 90L and the right end portion 90R are arranged substantially horizontally and extend substantially along the front and rear of the vehicle 1. The intermediate portion 90M extends along the left and right of the vehicle 1 and connects the left end portion 90L and the right end portion 90R. The intermediate portion 90M is located in front of the left end portion 90L and the right end portion 90R and in front of the lower end of the steering shaft, that is, in front of the gear 40 and the steering angle sensor 45. With such an arrangement of the bar 90, when the vehicle 1 has a frontal collision, the bar 90 first contacts an obstacle. Therefore, it is easy to avoid damage to other component members located behind the bar 90.

[0022] As shown in Figure 3, the left end 90L and the right end 90R each have a non-deformable portion N proximal to the intermediate portion 90M and a flat plate portion F proximal to the bracket 100. The non-deformable portion N is the part in which the shape of the pipe material constituting the bar 90 is maintained without deformation. The flat plate portion F is the part in which the inner circumferential surfaces of the pipe material are in substantially contact with each other. The flat plate portion F is formed by pressing both ends of the pipe material. Bolt holes Fh are provided in the flat plate portion F. The flat plate portion F is placed on top of the bracket 100, and bolts 95 (see Figure 2) are inserted through the bolt holes Fh of the flat plate portion F and the bolt holes of the bracket 100, and then tightened with nuts to fix it to the left and right arms 80. Since the axis of the bolt 95 is positioned almost vertically, the nuts can be tightened by arranging a tightening tool from below the flat plate portion F. Therefore, the tightening tool does not interfere with the arms 80.

[0023] When the bar 90 in this example is viewed from the front, the axis of the intermediate section 90M is located below the line segment connecting the left end of the axis of the left arm 80L and the right end of the axis of the right arm 80R. Furthermore, the axis of the intermediate section 90M is located below the steering angle sensor 45. When vehicle 1 is involved in a frontal collision, the load acting on the intermediate section 90M acts on the arm 80 from the front and below of vehicle 1 diagonally upward and rearward via the left end 90L, the right end 90R, and the bracket 100. Therefore, it is difficult for a load to act on the left and right arms 80 that would cause both ends of the arms 80 to spread apart.

[0024] The thickness of the left end (90L) and right end (90R) of the pipe material is greater than the thickness of the middle section (90M). Here, the thicknesses of the left end (90L), right end (90R), and middle section (90M) refer to the distance between the outer and inner surfaces of the pipe material. As will be described later, if the pipe material is made up of multiple tubes, the sum of the thicknesses of all the pipe materials corresponds to the thickness of the left end (90L) and right end (90R). If the pipe material is made up of a single tube, the difference between the inner and outer diameters of that pipe material corresponds to the thickness of the left end (90L), right end (90R), or middle section (90M).

[0025] To make the thickness of the left end 90L and the right end 90R thicker than the thickness of the middle section 90M, for example, only the left end 90L and the right end 90R can be formed by stacking multiple pipe materials in a multi-layered manner. That is, the middle section 90M is made of a single pipe, while the left end 90L and the right end 90R are made of multi-layered pipes. In this example, the left end 90L and the right end 90R are made of double pipes consisting of an outer pipe 90o and an inner pipe 90i, as shown in Figure 3. The material and thickness of the outer pipe 90o and the inner pipe 90i may be the same or different. In this example, the material and thickness of the outer pipe 90o and the inner pipe 90i are the same. The material of the outer pipe 90o and the inner pipe 90i is, for example, STKM13A (carbon steel pipe for machine structures). Unlike this example, the left end 90L and the right end 90R may be made of multi-layered pipes of three or more layers. Furthermore, unlike this example, a pipe material with a uniform thickness along its entire length may be prepared, and the outer circumference of the section corresponding to the middle part 90M of the pipe material may be partially removed by cutting or grinding. In this case as well, the thickness of the left end 90L and the right end 90R will be relatively thicker than the thickness of the middle part 90M.

[0026] The thickness of the 90M middle section should be selected so that it can deform and absorb the impact of a frontal collision at the vehicle's maximum speed. One example of a thickness for the 90M middle section is 1.6 mm.

[0027] The thickness of the left end (90L) and the right end (90R) should be selected based on the following considerations. An example of a thickness for the left end (90L) and right end (90R) is 3.2 mm. (A) It must have sufficient strength to not deform under the load when lifting the front of vehicle 1. An example of the load when lifting the front of vehicle 1 is 100 kg. (B) When the vehicle 1 collides head-on with an obstacle at its maximum speed, the intermediate section 90M must be deformed, but the bar 90 must have sufficient strength so that it does not interfere with the gear 40 and the steering angle sensor 45. (C) In the event of a frontal collision of vehicle 1, even if the middle section 90M of bar 90 deforms, the left end 90L and the right end 90R will not undergo excessive deformation, including buckling, and the left arm 80L and the right arm 80R will not undergo excessive deformation.

[0028] Of the left end 90L and the right end 90R, the regions where the thickness is greater than the intermediate section 90M are, for example, the flat section F, the transition section T from the non-deformable section N to the flat section F, and the vicinity of the transition section T in the non-deformable section N, as shown in Figure 3. The transition section T is the part between the non-deformable section N and the flat section F where the inner surface of the pipe material approaches the flat section F from the non-deformable section N. By constructing the entire area from the non-deformable section N to the tip of the flat section F with multiple tubes, it is easier to satisfy the requirements (A) to (C) described above.

[0029] With the configuration described above, vehicle 1 in this example achieves the following effects. When lifting the front of vehicle 1, the bar 90 can be used as a handle. When vehicle 1 has come off a wheel or the like, the worker can usually lift vehicle 1 by gripping the bar 90 with their legs bent and then extending their legs. Because the axis of the middle section 90M of the bar 90 is located below the line segment connecting the left end of the axis of the left arm 80L and the right end of the axis of the right arm 80R, it is easier to gain lift from the ground of the front wheels 20 compared to when the axis of the middle section 90M of the bar 90 is located above the aforementioned line segment. The position of the bar 90 is offset both forward and downward relative to the gear 40 and the steering angle sensor 45. Therefore, even if the middle section 90M of the bar 90 deforms during a collision, it is less likely to interfere with the gear 40 and the steering angle sensor 45. This makes it easier to avoid the vehicle 1 becoming immobile during a collision. - The thickness of the left end 90L and the right end 90R of the pipe material is greater than the thickness of the middle section 90M, making the middle section 90M relatively thinner than the left and right ends 90L and 90R. When vehicle 1 collides with an obstacle, the middle section 90M deforms preferentially, making it easier to absorb the impact of the collision. The absorption of impact by the middle section 90M can reduce damage to the left and right arms 80 and the members in their vicinity. The members in the vicinity include the gear 40 and the steering angle sensor 45. The relative thickness of the left and right ends 90L and 90R of the bar 90 compared to the middle section 90M increases the mounting strength of the bar 90 to both arms 80, and makes the left and right ends 90L and 90R of the bar 90 and both arms 80 less prone to deformation. In particular, it is difficult for loads to act on the left and right arms 80 that would cause both ends of the arms 80 to spread apart to the left and right. If a load is applied that causes both ends of the arm 80 to open, the intermediate section 90M may not be able to deform effectively, or an obstacle that collides with the front may come into contact with the gear 40 and the steering angle sensor 45. If it is difficult for a load to be applied to the arm 80 that causes both ends to open, the risk of damage to the gear 40 and the steering angle sensor 45 can be reduced. In addition, the left and right ends 90L and 90R of the bar 90 are resistant to buckling. Because the ends 90L and 90R are resistant to buckling, the intermediate section 90M can be deformed preferentially.

[0030] The present invention is not limited to these examples, but is intended to include all modifications within the meaning and scope equivalent to the claims as shown by the claims. In the above embodiment, the flat plate portion F is positioned substantially horizontally, and the axis of the bolt 95 is positioned substantially vertically. The creepage direction of the flat plate portion F is not limited to substantially horizontal as in the embodiment. For example, the flat plate portion F may be formed so that it is positioned substantially vertically and the axis of the bolt 95 is positioned substantially horizontally. In that case, it goes without saying that the creepage direction of the surface to which the flat plate portion F is attached in the bracket 100 should also be changed to match the creepage direction of the flat plate portion F. [Explanation of Symbols]

[0031] 1. Personal mobility (vehicle) 10 frames 11 Mainframe 12 Steering column 13 Battery holder 20 Front Wheel 20L left front wheel 20R Right front wheel 30 handle 40 gears 45. Steering angle sensor 50 Tie Rod 60 Steering Knuckle 61 Upper Plate 62 Lower Plate 63 Middle Plate 65 Kingpin 66 Cylinder part 67 spindles 70 Armrest 71 Front Plate 72 Rear Plate 73 Middle Plate 74 Rotation axis 80 Arm 80L Left Arm 80R Right Arm 80E Elastic material 90 bar 90L left end 90R Right end 90M middle part 90o outer tube 90i inner tube 95 volts 100 brackets F flat plate part Fh bolt hole N Non-deformable part T transition section

Claims

[Claim 1] The left arm supporting the left front wheel and the right arm supporting the right front wheel, The left arm and the right arm are provided with a bar that spans across them, The bar is made of a pipe material having each end attached to the left arm or the right arm, and an intermediate portion positioned forward of each end. The thickness of each end of the pipe material is greater than the thickness of the intermediate portion. Personal mobility.

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