Mobile vehicle

Abstract

To easily and affordably establish an operation unit in a vehicle for transfer that can adjust a rotation range of a wheel by operation of the operation unit.SOLUTION: A walking vehicle includes: a protruding pin 47 disposed on a rotation shaft 41b of a front wheel extending in an up-down direction and protruding in a direction intersecting with the rotation shaft 41b; and a recessed portion 62 opened to the protruding pin 47 side in the up-down direction. The recessed portion 62 includes a first region 62a on the open side and a second region 62b disposed behind the first region 62a and having a width narrower than that of the first region 62a. When the protruding pin 47 is inserted into the first region 62a, the displacement of the protruding pin 47 in a rotation direction of the front wheel is restricted within the width of the first region 62a, and thus the rotation range of the front wheel is restricted to 90°. When the protruding pin 47 is inserted into the second region 62b, the displacement of the protruding pin 47 toward both sides in the rotation direction of the front wheel is restricted, and thus the rotation of the front wheel is prohibited. The recessed portion 62 is displaceable in the up-down direction and is provided with an operation unit 55 displaceable in the up-down direction with the recessed portion 62.SELECTED DRAWING: Figure 4

Description

【Technical Field】 【0001】 The present invention relates to a vehicle for movement. 【Background Art】 【0002】 Conventionally, as vehicles for movement that assist in the movement of people and luggage, walking aids for assisting the walking of the elderly, etc., carrier carts used when carrying luggage, wheelchairs, baby strollers, etc. are known. The vehicle for movement has a handle on the upper end side and wheels on the lower end side. Also, some vehicles for movement are configured such that the wheels can rotate about a rotation shaft portion extending in the vertical direction. For example, there are those in which the wheels are provided integrally with the rotation shaft portion and can rotate together with the rotation shaft portion. In such a vehicle for movement, by rotating the wheels, the direction in which the vehicle for movement moves can be changed. 【0003】 Patent Document 1 discloses a walking aid provided with an adjustment mechanism capable of adjusting the rotation range of the front wheels. In this walking aid, the front wheels are casters, and the adjustment mechanism is provided on a caster cover provided above the front wheels. Specifically regarding the adjustment mechanism, a notch that is open upward is formed on the front side of the caster cover, and an engaging portion that can engage with the notch is provided above the notch. The notch is formed to have a wide upper region and a narrow lower region. Also, the engaging portion has a convex shape protruding downward and is provided so as to be vertically movable. Further, a protrusion is provided on the engaging portion, and the engaging portion is vertically moved by pinching the protrusion. 【0004】 The engaging portion can be displaced between an upper position where it engages with the upper region of the notch and a lower position where it engages with the lower region of the notch by moving vertically. When the engaging portion is in the upper position, the displacement of the engaging portion is restricted within the width of the upper region, and as a result, the rotation range of the front wheels is restricted to a predetermined angle (for example, 90°). Also, when the engaging portion is in the lower position, the displacement of the engaging portion itself is restricted, and as a result, a locked state is achieved in which the rotation of the front wheels is prohibited. Thus, according to the adjustment mechanism of Patent Document 1, the rotation range of the front wheels can be adjusted in multiple steps. [Prior art documents] [Patent Documents] 【0005】 [Patent Document 1] Japanese Patent Publication No. 2001-224642 [Overview of the Initiative] [Problems that the invention aims to solve] 【0006】 By the way, in the adjustment mechanism of Patent Document 1 described above, since the operating part (operating part) is provided on the convex engaging part that fits into the notch, the operating part tends to become small, which may make it difficult to operate. 【0007】 This invention has been made in view of the above circumstances, and its main purpose is to make it easier to construct an operating unit in a mobile vehicle in which the range of rotation of the wheels can be adjusted by operating the operating unit. [Means for solving the problem] 【0008】 To solve the above problems, the first invention provides a mobile vehicle equipped with wheels that are rotatable together with a pivot shaft that extends vertically, the mobile vehicle being equipped with a projection provided on the pivot shaft and projecting in a direction intersecting the pivot shaft, and a concave portion that is open on the side of the projection in the vertical direction, the concave portion having a first region on the open side and a second region provided further back than the first region and narrower than the first region, and when the projection enters the first region, the projection in the rotation direction of the wheel The rotation range of the wheel is limited to a first range by restricting the displacement to within the width of the first region, and when the protrusion enters the second region, the rotation of the wheel is prohibited by restricting the displacement of the protrusion on both sides in the rotation direction, or the rotation range of the wheel is limited to a second range smaller than the first range by restricting the displacement of the protrusion in the rotation direction to within the width of the second region, and the concave portion is displaceable in the vertical direction, and the device is equipped with an operating part that can be displaced vertically together with the concave portion by user operation. 【0009】 According to the first invention, a projection is provided on the pivot axis of a wheel that extends vertically, projecting in a direction intersecting the pivot axis. Furthermore, a concave portion is provided that is open on the side of the projection in the vertical direction, and this concave portion has a first region on the open side and a second region located further back than the first region and narrower than the first region. When the projection enters the first region of the concave portion, the displacement of the projection in the direction of rotation of the wheel is restricted to within the width of the first region, thereby limiting the range of rotation of the wheel to a first range. When the projection enters the second region, the displacement of the projection on both sides in the direction of rotation of the wheel is restricted, thereby prohibiting the rotation of the wheel, or the displacement of the projection in the direction of rotation of the wheel is restricted to within the width of the second region, thereby limiting the range of rotation of the wheel to a second range smaller than the first range. This makes it possible to adjust the range of rotation of the wheel. 【0010】 Furthermore, the concave portion is displaceable in the vertical direction and is equipped with an operating portion that is displaceable in the vertical direction along with the concave portion. In this case, the range of rotation of the wheel can be adjusted by operating the operating portion to insert the protruding portion into either the first or second region of the concave portion. In this configuration, the protruding portion is the fixed side and the concave portion is the movable side, and the concave portion on the movable side is displaceable in the vertical direction along with the operating portion, making it easy to construct the operating portion in a way that allows for a larger operating portion or improved operability. 【0011】 The mobile vehicle of the second invention is provided with a cylindrical portion that extends vertically and has a cylindrical shape through which the pivot shaft portion is inserted, the operating portion is arranged on the outer circumference of the cylindrical portion, a movable portion is provided between the cylindrical portion and the pivot shaft portion that is connected to the operating portion via a connector and is displaceable vertically together with the operating portion, the cylindrical portion has an elongated through hole that extends vertically and through which the connector is inserted, and the concave portion is formed in the movable portion. 【0012】 According to the second invention, a cylindrical portion is provided through which a pivot shaft is inserted, and an operating portion is provided on the outer circumference of the cylindrical portion. A movable portion is provided between the cylindrical portion and the pivot shaft, connected to the operating portion via a connector. Furthermore, an insertion hole is formed in the cylindrical portion through which the connector is inserted, and this insertion hole is formed as an elongated hole extending in the vertical direction. In this configuration, when the operating portion is operated in the vertical direction, the movable portion is displaced vertically together with the operating portion. At this time, the connector is also displaced vertically along the insertion hole. In this configuration, the second invention has a concave portion formed in the movable portion located inside the cylindrical portion. In this case, it is possible to prevent foreign matter such as dust from entering the concave portion, and thus prevent the problem of foreign matter accumulating in the concave portion and making it impossible to limit the rotation range of the wheel. 【0013】 The mobile vehicle of the third invention is, in the second invention, wherein the movable part is cylindrical in shape surrounding the pivot shaft, the connectors are provided on both sides of the movable part in the radial direction, the cylindrical part has an insertion hole for each connector, and the operating part extends along the circumferential direction of the cylindrical part and is connected to the connectors inserted through each of the insertion holes. 【0014】 According to the third invention, in the above-described configuration in which the movable part is displaced vertically by operating the operating part, the movable part can be displaced in a stable state. Furthermore, since the operating part can be formed to be relatively large along the circumferential direction of the cylindrical part, the operating part can be made easier to hold, thus improving operability. 【0015】 The mobile vehicle of the fourth invention, in the third invention, has extensions at both ends in the vertical direction that extend to the side opposite to the cylindrical part. 【0016】 According to the fourth invention, when operating the operating part in the vertical direction, it is possible to further improve operability by, for example, placing a finger on the extended part to operate it. 【0017】 The mobile vehicle of the fifth invention is formed such that, in the third invention, the operating part is sized to cover the entirety of each insertion hole, regardless of which position it is in which it is displaceable in the vertical direction. 【0018】 According to the fifth invention, regardless of the position in which the operating part is displaceable in the vertical direction, the entire insertion hole of the cylindrical part is covered by the operating part. This prevents foreign matter from entering the inside of the cylindrical part through the insertion hole. Therefore, the accumulation of foreign matter in the concave part located inside the cylindrical part can be further suppressed. 【0019】 The mobile vehicle of the sixth invention is, in the second invention, wherein the protrusion is a first protrusion, the cylindrical portion is provided with a second protrusion that protrudes toward the operating portion, an engaging member that can engage with the second protrusion is attached to the back side of the operating portion, and the engaging member engages with the second protrusion when the first protrusion enters the first region of the concave portion which is displaced vertically together with the operating portion, and when the first protrusion enters the second region. 【0020】 According to the sixth invention, a second projection is provided on the cylindrical portion that protrudes toward the operating portion, and an engaging member that can engage with the second projection is attached to the back side of the operating portion. The engaging member engages with the second projection when the first projection enters a first region of a concave portion that displaces vertically together with the operating portion, and when the first projection enters a second region. In this case, it is possible to maintain a state in which the rotation range of the wheel is limited to a first range when the first projection enters the first region, and it is also possible to maintain a state in which the rotation of the wheel is restricted or the rotation range of the wheel is limited to a second range when the first projection enters the second region. 【0021】 Furthermore, since the engaging member is provided on the back side of the operating part, the engaging member can be covered by the operating part regardless of its position. This effectively prevents foreign matter from entering the engaging member, and as a result, prevents the accumulation of foreign matter in the engaging member, which would prevent it from engaging with the second protrusion. 【0022】 The seventh invention is a mobile vehicle in which, in any of the second to sixth inventions, the cylindrical portion is an axle holder in which a pair of upper and lower bearing portions for receiving the pivot shaft portion are disposed inside, and the movable portion is displaceable in the vertical direction between the respective bearing portions. 【0023】 The rotating shaft portion of the wheel may be supported by a pair of upper and lower bearing portions disposed inside the shaft holder. Therefore, in the seventh invention, in such a configuration, the movable portion is displaceable in the vertical direction between the respective bearing portions inside the shaft holder. In this case, the internal space of the shaft holder can be effectively used to move the movable portion up and down. 【Brief Description of the Drawings】 【0024】 [Figure 1] It is a perspective view of the walking vehicle seen from obliquely in front. [Figure 2] It is a perspective view showing the vicinity of the front wheel. [Figure 3] It is a perspective view showing the vicinity of the shaft holder with the operation portion removed. [Figure 4] It is a perspective view showing the internal structure of the shaft holder with the operation portion and the shaft holder removed. [Figure 5] It is a front view showing the internal structure of the shaft holder with a part of the shaft holder broken, where (a) shows the case where the slider is in the first position, (b) shows the case where the slider is in the second position, and (c) shows the case where the slider is in the third position. [Figure 6] It is a perspective view of the vicinity of the operation portion and the slider seen obliquely from behind with the shaft holder removed. [Figure 7] It is a cross-sectional view showing the back side of the operation portion, where (a) shows the case where the slider that moves up and down together with the operation portion is in the first position, (b) shows the case where the slider is in the second position, and (c) shows the case where the slider is in the third position. 【Embodiments for Carrying Out the Invention】 【0025】 Hereinafter, an embodiment embodying the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of the walking vehicle 10 seen obliquely from the front. In the following description, the moving direction when moving the walking vehicle 10 is defined as the front-back direction, and the direction orthogonal to the front-back direction is defined as the left-right direction for the description. 【0026】 As shown in Figure 1, the walker 10 comprises a pair of left and right frame sections 11 extending in the vertical direction, and a front wheel 12 and a rear wheel 13 provided on the lower end of each frame section 11. Each frame section 11 is connected to the others via a connecting member 14. The walker 10 corresponds to a vehicle for mobility. 【0027】 Each frame section 11 has a lower frame 15 located at its lower part and extending in the front-rear direction, and a vertical frame 16 extending upward from the middle of the lower frame 15. The front wheel 12 is attached to the front end of the lower frame 15, and the rear wheel 13 is attached to the rear end of the lower frame 15. 【0028】 The vertical frames 16 are formed from metal pipes. Inside each vertical frame 16, a support frame 17 is inserted from above. The support frame 17 is formed from metal pipes and extends vertically. The support frame 17 can be adjusted vertically while inserted into the vertical frames 16. The support frame 17 is then fixed to the vertical frames 16 in its adjusted position using a screw member 18. 【0029】 A handle 22 and a brake lever 23 are provided on the upper end of the support frame 17 via a mounting member 21. The handle 22 is the part that the user grips when moving the walker 10. The height of the handle 22 can be adjusted by adjusting the vertical position of the support frame 17. The brake lever 23 is for operating the brakes and is located below the handle 22. The mounting member 21 also has a handle 24 formed therein for gripping when lifting the walker 10 over steps or other obstacles. 【0030】 A seat 31 is provided between each of the vertical frames 16. The seat 31 can be sat on from the rear. Behind the seat 31, a pair of basket support sections 32 are provided on the left and right. In stores such as supermarkets, shopping baskets can be placed on each basket support section 32 and the seat 31 for shopping. The basket support sections 32 can also be rotated outwards in the left and right directions (see the dashed line in Figure 1). When sitting on the seat 31, each basket support section 32 is rotated outwards in the left and right directions before sitting down. 【0031】 A backrest 34 is provided above the seat 31. The backrest 34 supports the back of the user seated on the seat 31 and is stretched across the upper ends of each vertical frame 16. In addition, a storage compartment 36 capable of accommodating items is provided in front of the seat 31. 【0032】 Next, the configuration around the front wheel 12 will be explained based on Figures 2 to 4. Figure 2 is a perspective view showing the area around the front wheel 12. Figure 3 is a perspective view showing the area around the axle holder 43 with the operating unit 55 removed. Figure 4 is a perspective view showing the internal structure of the axle holder 43 with both the operating unit 55 and the axle holder 43 removed. Note that the front wheel 12 corresponds to the wheel. 【0033】 As shown in Figure 2, a shaft member 41 is attached to the front wheel 12. The shaft member 41 is formed by bending a round bar at multiple points. The shaft member 41 has a rotating shaft portion 41a that extends in the left-right direction and is attached to the front wheel 12, a pivot shaft portion 41b that extends in the vertical direction above the front wheel 12, and an intermediate shaft portion 41c that connects the rotating shaft portion 41a and the pivot shaft portion 41b. The rotating shaft portion 41a is inserted through the center of the front wheel 12. This allows the front wheel 12 to rotate around the rotating shaft portion 41a. The pivot shaft portion 41b is supported by a shaft holder 43 provided at the front end of the lower frame 15, as shown in Figures 2 and 3. The shaft holder 43 is formed in a cylindrical shape that extends in the vertical direction, and its upper end opening is closed by a cap 44. The shaft holder 43 corresponds to the cylindrical portion. 【0034】 As shown in Figure 4, a pair of upper and lower bearings 45 are arranged inside the shaft holder 43. Each bearing 45 is an annular rolling bearing and is spaced apart in the vertical direction. The pivot shaft portion 41b is inserted into the shaft holder 43 from below and passes through the inside of each bearing 45. As a result, the pivot shaft portion 41b is rotatably supported by each bearing 45, and consequently the shaft member 41 is supported by the shaft holder 43 via each bearing 45. With this configuration, the front wheel 12 can rotate (swivel) together with the shaft member 41 around the pivot shaft portion 41b. Therefore, in this walker 10, the direction of movement of the walker 10 can be changed by rotating the front wheel 12. 【0035】 Furthermore, the portion of the pivot shaft 41b that protrudes above the upper bearing 45 is threaded. A nut 46 is fastened to this threaded portion, thereby preventing the pivot shaft 41b from falling out of the bearing 45. The nut 46 is covered by a cap 44. The bearing 45 corresponds to the bearing portion. 【0036】 Here, the walking vehicle 10 is provided with an adjustment mechanism that allows the rotation range of the front wheels 12 to be adjusted in multiple stages. The adjustment mechanism is provided for each of the left and right front wheels 12. The adjustment mechanism will be explained below with reference to Figures 2 to 4, as well as Figure 5. Figure 5 is a front view showing the internal structure of the axle holder 43 with a part of the axle holder 43 cut away, where (a) shows the case where the slider 51 is in the first position E1, (b) shows the case where the slider 51 is in the second position E2, and (c) shows the case where the slider 51 is in the third position E3. 【0037】 As shown in Figures 4 and 5(a), a cylindrical protruding pin 47 is provided on the pivot shaft portion 41b. A radially extending hole 48 is provided on the pivot shaft portion 41b, and the protruding pin 47 is inserted into the hole 48 with a portion protruding from the circumferential surface of the pivot shaft portion 41b. Therefore, the protruding pin 47 is provided in a state where it protrudes in a direction perpendicular to the pivot shaft portion 41b. The protruding pin 47 corresponds to the protruding portion and the first protruding portion. 【0038】 More specifically, a female thread is formed on the inner circumferential surface of the hole 48, and a male thread is formed on the outer circumferential surface of the projection pin 47. The projection pin 47 is installed in a screwed state into the hole 48. When screwing in the projection pin 47, a hexagonal wrench is inserted into the hexagonal hole formed at the tip of the projection pin 47, and the pin is screwed in using the hexagonal wrench. In addition, a hole 49 is formed in the shaft holder 43 at a position corresponding to the projection pin 47, through which a hexagonal wrench can be inserted, allowing the projection pin 47 to be tightened further using the hexagonal wrench through the hole 49. 【0039】 A slider 51 is provided inside the shaft holder 43. The slider 51 is an annular shape that surrounds the pivot shaft portion 41b and is positioned between each bearing 45. The slider 51 is slidable (displaceable) in the vertical direction along the pivot shaft portion 41b. The slider 51 is the movable part. 【0040】 The slider 51 is positioned below the protruding pin 47. The slider 51 has a recessed portion 52 that is open upward. In this case, the recessed portion 52 is open towards the protruding pin 47. The recessed portion 52 has a first region 52a on the open side and a second region 52b located further back than the first region 52a. The first region 52a and the second region 52b are continuous regions vertically. The width W1 of the first region 52a (more specifically, the width in the circumferential direction of the slider 51; the same applies to the width W2 below) is greater than the width W2 of the second region 52b. Therefore, the first region 52a is a wide region, and the second region 52b is a narrow region. The width W2 of the second region 52b is approximately the same as the diameter of the protruding pin 47, and more specifically, slightly larger than the diameter of the protruding pin 47. 【0041】 The slider 51 is displaceable between a first position E1 (shown in Figure 5(a)) where the protruding pin 47 does not enter the concave portion 52, a second position E2 (shown in Figure 5(b)) where the protruding pin 47 enters the first region 52a of the concave portion 52, and a third position E3 (shown in Figure 5(c)) where the protruding pin 47 enters the second region 52b of the concave portion 52. The second position E2 is above the first position E1, and the third position E3 is above the second position E2. Therefore, the first position E1 can also be called the lower position, the second position E2 the intermediate position, and the third position E3 the upper position. 【0042】 As described above, since the protruding pin 47 is provided on the pivot shaft portion 41b of the front wheel 12, when the front wheel 12 rotates together with the pivot shaft portion 41b, the protruding pin 47 is displaced in the direction of rotation of the front wheel 12 (in other words, in the circumferential direction of the pivot shaft portion 41b). When the slider 51 is in the first position E1, as shown in Figure 5(a), the displacement of the protruding pin 47 in the direction of rotation of the front wheel 12 is not restricted by the concave portion 52. Therefore, the rotation range of the front wheel 12 is not restricted, and the front wheel 12 can rotate 360°. 【0043】 Furthermore, when the slider 51 is in the second position E2, as shown in Figure 5(b), the displacement of the protruding pin 47 in the rotational direction of the front wheel 12 is limited to within the width of the first region 52a of the concave portion 52. Therefore, the rotational range of the front wheel 12 is limited to a range of 90° (corresponding to the first range). In this case, the front wheel 12 can rotate 45° to the left and 45° to the right. 【0044】 Furthermore, when the slider 51 is in the third position E3, the displacement of the protruding pins 47 on both sides in the rotational direction of the front wheel 12 is prohibited, as shown in Figure 5(c). As a result, the rotation of the front wheel 12 is prohibited, and the front wheel 12 becomes locked. 【0045】 An operating section 55, which is operable in the vertical direction, is provided on the outer circumference of the shaft holder 43. The operating section 55 is located on the front side of the shaft holder 43 and is made of, for example, a hard resin. The operating section 55 extends in a substantially arc shape along the circumferential surface of the shaft holder 43, and more specifically, in a semi-circular arc shape. The operating section 55 has a pair of dividing members 55a and 55b that are divided in the left-right direction, and these dividing members 55a and 55b are connected to each other by screws 56. 【0046】 The operating section 55 has extensions 57 that extend forward from both its upper and lower ends. In this case, each extension 57 extends to the side opposite to the shaft holder 43. Each extension 57 extends in the left-right direction of the operating section 55, and more specifically, extends across the entire left-right area of ​​the operating section 55. When operating the operating section 55 up and down, it is possible to operate it by placing a finger on the extension 57. 【0047】 The operating section 55 is connected to the slider 51 via connecting pins 58. The connecting pins 58 are provided on both radial sides of the slider 51, and more specifically, on both left-right sides of the slider 51. Each connecting pin 58 extends in the left-right direction, with one end inserted into a hole 61 formed in the slider 51 and the other end inserted into a concave hole 62 formed on the back surface of the operating section 55. The connecting pins 58 correspond to the connectors. 【0048】 The shaft holder 43 has a pair of through holes 65 through which each connecting pin 58 is inserted. Each through hole 65 is an elongated hole shape that extends in the vertical direction. In this configuration, when the operating part 55 is operated in the vertical direction, the slider 51 is displaced vertically together with the operating part 55. At the same time, the connecting pin 58 inserted through the through hole 65 is displaced vertically along the through hole 65. 【0049】 By operating the control unit 55 in the vertical direction, the slider 51 can be displaced to the first position E1 (see Figure 5(a)), the second position E2 (see Figure 5(b)), and the third position E3 (see Figure 5(c)) as described above (see also Figure 7). As a result, by operating the control unit 55, the rotation range of the front wheel 12 can be adjusted to 360°, 90°, and 0°, respectively. 【0050】 Furthermore, when the operating section 55 is operated in the vertical direction, the connecting pin 58 is displaced vertically along the insertion hole 65 of the shaft holder 43, as described above. In this case, the range in which the operating section 55 can be displaced vertically is defined by the vertical length of the insertion hole 65. In this embodiment, when the slider 51 is in the first position E1, the operating section 55 is in its lowest position (see Figure 7(a)), and when the slider 51 is in the third position E3, the operating section 55 is in its highest position (see Figure 7(c)). In this embodiment, regardless of which position the operating section 55 is in within its vertical displacement range, the operating section 55 covers the entirety of each insertion hole 65 (see Figures 7(a) to (c)). 【0051】 Next, the configurations for holding the slider 51 in the first position E1, second position E2, and third position E3 will be explained using Figures 6 and 7. Figure 6 is a perspective view of the area around the operating section 55 and the slider 51 from the rear at an oblique angle with the shaft holder 43 removed. Figure 7 is a cross-sectional view showing the back side of the operating section 55, where (a) shows the case where the slider 51, which displaces vertically with the operating section 55, is in the first position E1, (b) shows the case where the slider 51 is in the second position E2, and (c) shows the case where the slider 51 is in the third position E3. Note that Figures 7(a) to (c) show cross-sectional views cut along a plane perpendicular to the connecting pin 58 and the engaging pin 67. Also, in Figures 7(a) to (c), for the sake of explanation, the slider 51 is shown by a dashed line and the insertion hole 65 of the shaft holder 43 is shown by a dashed line. 【0052】 As shown in Figures 4 to 6 and Figure 7(a), the shaft holder 43 has engagement pins 67 attached to both sides in the left-right direction. Each engagement pin 67 extends in the left-right direction and is attached by being inserted through a hole 69 formed in the shaft holder 43. In this case, the engagement pin 67 protrudes toward the operating part 55, and its end is inserted into a concave passage 68 formed on the back surface of the operating part 55. The passage 68 extends in the vertical direction and is positioned above the hole 62 into which the connecting pin 58 is inserted. When the operating part 55 is displaced vertically together with the slider 51, the engagement pin 67 is displaced along the passage 68 accordingly. The engagement pin 67 corresponds to the second protrusion. 【0053】 An engaging member 71, which can engage with an engaging pin 67, is attached to the back side of the operating section 55. The engaging member 71 is housed in a housing recess 72 formed on the back side of the operating section 55. The housing recess 72 extends vertically along the passage section 68 and is continuous with the passage section 68 in the width direction of the passage section 68. 【0054】 The engaging member 71 is formed by bending a long, elastic spring plate. The engaging member 71 has a plate portion 71a extending in the vertical direction and a pair of bent portions 71b bent in a U-shape at both ends of the plate portion 71a so as to be convex in opposite directions. In addition, the engaging member 71 has a pair of engaging portions 71c and 71d provided on the opposite side of the plate portion 71a from the bent portion 71b. These engaging portions 71c and 71d are located at both ends of the engaging member 71 and are arranged side by side in the vertical direction. 【0055】 The engaging member 71 is arranged such that each engaging portion 71c, 71d is located on the passage portion 68 side relative to the plate portion 71a. Each engaging portion 71c, 71d is formed in a mountain shape that protrudes toward the passage portion 68. Each engaging portion 71c, 71d can be displaced toward the opposite side from the protruding side by the elastic deformation of the bent portion 71b. Of the engaging portions 71c, 71d, the upper engaging portion is engaging portion 71c, and the lower engaging portion is engaging portion 71d. 【0056】 As shown in Figure 7(a), when the slider 51, which displaces vertically together with the operating section 55, is in the first position E1, the engagement pin 67 is in the upper position K1 in the passage section 68. In this case, the engagement portion 71c of the engagement member 71 engages with the engagement pin 67 from below, and this engagement restricts the upward displacement of the operating section 55, and consequently restricts the displacement of the slider 51 toward the second position E2. Therefore, the slider 51 is held in the first position E1. 【0057】 When the operating part 55 is operated upward, the slider 51 is displaced from the first position E1 to the second position E2, causing the engagement pin 67 to be displaced (relatively displaced) from the upper position K1 to the lower intermediate position K2 in the passage portion 68. At this time, the engagement pin 67 is displaced from the upper position K1 to the intermediate position K2, overcoming the engagement portion 71c. More specifically, at this time, the engagement pin 67 pushes the engagement portion 71c to the opposite side of the engagement pin 67, releasing the engagement of the engagement portion 71c with respect to the engagement pin 67, and in this released state, the engagement pin 67 is displaced to the intermediate position K2. 【0058】 As shown in Figure 7(b), when the engagement pin 67 is located at the intermediate position K2 in the passage 68, the engagement portion 71c of the engagement member 71 engages with the engagement pin 67 from above, and this engagement restricts the downward displacement of the operating portion 55, and consequently restricts the displacement of the slider 51 toward the first position E1. In this case, the engagement portion 71d of the engagement member 71 also engages with the engagement pin 67 from below, and this engagement restricts the upward displacement of the operating portion 55, and consequently restricts the displacement of the slider 51 toward the third position E3. As a result, the slider 51 is held at the second position E2. 【0059】 As the operating section 55 is operated further upward, the slider 51 is displaced from the second position E2 to the third position E3, causing the engagement pin 67 to be displaced (relatively displaced) from the intermediate position K2 to a lower position K3 in the passage section 68. At this time, the engagement pin 67 is displaced from the intermediate position K2 to the lower position K3, overcoming the engagement portion 71d. More specifically, at this time, the engagement portion 71d is pushed by the engagement pin 67 to the opposite side of the engagement pin 67, releasing the engagement of the engagement portion 71d with respect to the engagement pin 67, and in this released state, the engagement pin 67 is displaced to the lower position K3. 【0060】 As shown in Figure 7(c), when the engagement pin 67 is in the lower position K3 in the passage 68, the engagement portion 71d engages with the engagement pin 67 from above, and this engagement restricts the downward displacement of the operating portion 55, and consequently restricts the displacement of the slider 51 toward the second position E2. As a result, the slider 51 is held in the third position E3. 【0061】 As described in detail above, the configuration of this embodiment provides the following excellent effects. 【0062】 The front wheel 12 is provided with a protruding pin 47 that is located on the pivot shaft portion 41b and protrudes in a direction intersecting the pivot shaft portion 41b, and a concave portion 52 that is open on the side of the protruding pin 47 in the vertical direction. The concave portion 52 has a first region 52a on the open side and a second region 52b which is located further inside than the first region 52a and is narrower than the first region 52a. The concave portion 52 is also displaceable in the vertical direction and is further provided with an operating part 55 that is displaceable in the vertical direction together with the concave portion 52. In this case, the rotation range of the front wheel 12 can be adjusted by operating the operating part 55 to insert the protruding pin 47 into either the first region 52a or the second region 52b of the concave portion 52. In this configuration, the protruding pin 47 is fixed and the concave portion 52 is movable, and the concave portion 52 on the movable side is displaced vertically together with the operating portion 55. This makes it easy to construct the operating portion 55 in a way that allows for a larger operating portion 55 or improved operability. 【0063】 An axle holder 43 is provided through which a pivot shaft portion 41b is inserted, and an operating portion 55 is provided on the outer circumference of the axle holder 43. Between the axle holder 43 and the pivot shaft portion 41b, a slider 51 is provided, connected to the operating portion 55 via a connecting pin 58. In addition, an insertion hole 65 is formed in the axle holder 43 through which the connecting pin 58 is inserted, and the insertion hole 65 is formed as an elongated hole that extends in the vertical direction. In this configuration, when the operating portion 55 is operated in the vertical direction, the slider 51 is displaced vertically together with the operating portion 55. At this time, the connecting pin 58 is displaced vertically along the insertion hole 65. In this configuration, in the above embodiment, a concave portion 52 is formed in the slider 51 inside the axle holder 43. In this case, it is possible to suppress foreign matter such as dust from entering the concave portion 52, and thus it is possible to suppress the problem of foreign matter accumulating in the concave portion 52 and making it impossible to limit the rotation range of the front wheel 12. 【0064】 The slider 51 is cylindrical in shape and surrounds the pivot shaft portion 41b, and the connecting pins 58 are provided on both sides of the slider 51 in the radial direction. The operating portion 55 extends along the circumferential direction of the shaft holder 43 and is connected to the connecting pins 58 inserted through each of the insertion holes 65 of the shaft holder 43. In this configuration, the slider 51 is displaced vertically by operating the operating portion 55, and the slider 51 can be displaced in a stable manner. In addition, in this case, the operating portion 55 can be made relatively large along the circumferential direction of the shaft holder 43, which improves operability, such as making the operating portion 55 easier to hold. 【0065】 The operating section 55 has extensions 57 at both ends in the vertical direction, each extending away from the shaft holder 43. This allows for further improvement in operability, such as by using the extensions 57 to operate the operating section 55 in the vertical direction. 【0066】 The operating section 55 is formed to be large enough to cover the entire insertion hole 65, regardless of its position in the vertical direction where it can be displaced. This prevents foreign matter from entering the inside of the shaft holder 43 through the insertion hole 65. Therefore, the accumulation of foreign matter in the concave portion 52 inside the shaft holder 43 can be further suppressed. In this case, the operating section 55 can be made larger not only in the circumferential direction of the shaft holder 43 but also in the vertical direction, thereby further improving the operability of the operating section 55. 【0067】 An engagement pin 67 is provided on the shaft holder 43, protruding toward the operating section 55, and an engagement member 71 that can engage with the engagement pin 67 is attached to the back side of the operating section 55. The engagement member 71 engages with the engagement pin 67 in both cases: when the protruding pin 47 is in the first region 52a of the concave portion 52 which displaces vertically together with the operating section 55, and when the protruding pin 47 is in the second region 52b. In this case, it is possible to maintain a state in which the rotation range of the front wheel 12 is limited to a range of 90° when the protruding pin 47 is in the first region 52a, and a state in which the rotation of the front wheel 12 is restricted when the protruding pin 47 is in the second region 52b. 【0068】 Furthermore, since the engaging member 71 is provided on the back side of the operating section 55, the engaging member 71 can be covered by the operating section 55 regardless of the position of the operating section 55. This effectively prevents foreign matter from entering the engaging member 71, and as a result, prevents the accumulation of foreign matter in the engaging member 71, which would prevent it from engaging with the engaging pin 67. 【0069】 In a configuration where the pivot shaft portion 41b of the front wheel 12 is supported by a pair of upper and lower bearings 45 disposed inside the shaft holder 43, the slider 51 is made capable of vertical displacement between the bearings 45 inside the shaft holder 43. In this case, the slider 51 can be moved up and down by making good use of the internal space of the shaft holder 43. 【0070】 The present invention is not limited to the embodiments described above, and may be implemented, for example, as follows. 【0071】 In the above embodiment, when the protruding pin 47 enters the second region 52b of the concave portion 52, the rotation of the front wheel 12 is prohibited by restricting the displacement of the protruding pin 47 to both sides in the rotational direction of the front wheel 12. However, this may be changed. For example, by making the width of the second region 52b larger than in the above embodiment, when the protruding pin 47 enters the second region 52b, the displacement of the protruding pin 47 in the rotational direction of the front wheel 12 may be limited to within the width of the second region 52b. In this case as well, the width of the second region 52b is made smaller than the width of the first region 52a. By doing so, when the protruding pin 47 enters the second region 52b, the rotational range of the front wheel 12 is limited to a predetermined range (corresponding to the second range) that is smaller than 90° (i.e., the rotational range of the front wheel 12 when the protruding pin 47 enters the first region 52a). 【0072】 The concave portion 52 may be formed to open downwards. In this case, the slider 51 is positioned above the protruding pin 47, so that the concave portion 52 opens towards the protruding pin 47. In this configuration, the second position of the slider 51 (the position where the protruding pin 47 enters the first region 52a of the concave portion 52) is lower than the first position (the position where the protruding pin 47 does not enter the concave portion 52), and the third position (the position where the protruding pin 47 enters the second region 52b of the concave portion 52) is lower than the second position. 【0073】 In the above embodiment, a recessed portion 52 is formed on the slider 51, but this may be changed to form a recessed portion on the operating portion. In this case, the following configuration is possible: The slider 51 and the shaft holder 43 are omitted, and the operating portion is formed in a cylindrical shape surrounding the pivot shaft portion 41b. Then, a recessed portion is formed on the operating portion. In this case as well, the operating portion can be displaced vertically together with the recessed portion. 【0074】 In the above embodiment, a shaft holder 43 supporting the pivot shaft portion 41b was used as the cylindrical portion, but the cylindrical portion may be formed from something other than the shaft holder 43. 【0075】 In the above embodiment, the mobility vehicle of the present invention was embodied in a walker 10 for assisting elderly people and others with walking. However, the present invention is not limited to walkers 10, but can be applied to various mobility vehicles such as strollers, trolleys, wheelchairs, carts, and single-wheeled transport vehicles. Furthermore, the present invention does not necessarily have to be applied to the front wheels, but may be applied to rear wheels or other wheels besides the front wheels. [Explanation of Symbols] 【0076】 10... Walker as a vehicle for movement, 12... Front wheel as a wheel, 41b... Rotating shaft, 43... Shaft holder as a cylindrical part, 45... Bearing as a bearing part, 47... Protruding part and protruding pin as the first protruding part, 51... Slider as a movable part, 52... Concave part, 52a... First region, 52b... Second region, 55... Operating part, 57... Extension part, 58... Connecting pin as a connector, 65... Through hole, 67... Engaging pin as the second protruding part, 71... Engaging member.

Claims

[Claim 1] A mobile vehicle equipped with wheels that are rotatable together with a pivot shaft that extends in the vertical direction, A projection is provided on the aforementioned pivot shaft portion and protrudes in a direction intersecting the pivot shaft portion, It comprises a concave portion that is open to the side of the protruding portion in the vertical direction, The concave portion has a first region on the open side and a second region located further back than the first region and narrower than the first region. When the protrusion enters the first region, the displacement of the protrusion in the rotational direction of the wheel is limited to within the width of the first region, thereby limiting the rotational range of the wheel to the first range. When the protrusion enters the second region, the rotation of the wheel is prohibited by restricting the displacement of the protrusion on both sides in the rotation direction, or the rotation range of the wheel is limited to a second region smaller than the first region by limiting the displacement of the protrusion in the rotation direction to within the width of the second region. A cylindrical part that extends vertically, through which the pivot shaft portion is inserted, The cylindrical portion is provided with an operating part located on the outer circumference and which can be displaced vertically by user operation, Between the cylindrical portion and the pivot shaft portion, there is a movable portion that is connected to the operating portion via a connector and is capable of being displaced vertically together with the operating portion. The cylindrical portion has an elongated insertion hole that extends vertically and through which the connector is inserted. The aforementioned concave portion is a movable wheel formed in the movable portion. [Claim 2] The movable part is cylindrical in shape and surrounds the pivot shaft. The aforementioned connectors are provided on both sides of the movable part in the radial direction, The cylindrical portion has the insertion hole formed for each of the connectors, The mobile vehicle according to claim 1, wherein the operating section extends along the circumferential direction of the cylindrical portion and is connected to the connectors inserted into each of the insertion holes. [Claim 3] The mobile vehicle according to claim 2, wherein the operating section has extensions at both ends in the vertical direction that extend to the side opposite to the cylindrical section. [Claim 4] The mobile vehicle according to claim 2, wherein the operating section is formed to be large enough to cover the entirety of each of the insertion holes, regardless of which position it is in which it can be displaced in the vertical direction. [Claim 5] The aforementioned protrusion is the first protrusion, The cylindrical portion is provided with a second projection that protrudes toward the operating portion side. An engaging member that can engage with the second protrusion is attached to the back side of the operating part. The mobile vehicle according to claim 1, wherein the engaging member engages with the second protrusion when the first protrusion enters the first region of the concave portion which is displaced vertically together with the operating portion, and when the first protrusion enters the second region. [Claim 6] The cylindrical portion is a shaft holder in which a pair of upper and lower bearing portions are disposed inside to receive the rotating shaft portion. The movable part is displaceable in the vertical direction between the bearing parts, as described in any one of claims 1 to 5.

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