automated guided vehicle

Abstract

To provide an unmanned carrier allowing a lowered floor of a vehicle body while securing a load amount.SOLUTION: A weight of a vehicle body 10 and a load can be dispersed into a drive wheel 23 and a driven wheel 33 as an unmanned carrier comprises the driven wheel 33, so that smaller diameters of the drive wheel 23 and the driven wheel 33 can be realized. Thus, a lowered floor of a vehicle body can be realized while securing a load amount. In this case, both the drive wheel 23 and the driven wheel 33 can be easily grounded to a road surface G where the road surface G is corrugated as an oscillation mechanism 50 interposed between the drive wheel 23 and the drive wheel 33 and the vehicle body 10 and rockably supporting the drive wheel 23 and the driven wheel 33 to the vehicle body 10 is provided. Therefore a running incapability due to a decrease of a load of the drive wheel 23 or a breakdown due to a concentrated load to the drive wheel 23 can be restricted.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an automated guided vehicle, and more particularly to an automated guided vehicle that can achieve both a low floor vehicle body and a sufficient load capacity. [Background technology]

[0002] A two-wheel speed differential type automated guided vehicle is known (Patent Document 1), which includes a body on which cargo is loaded, left and right drive wheels arranged approximately in the center of the body in the longitudinal direction and configured to be driven independently, and casters arranged on the body and configured to be swivelable horizontally. In such an automated guided vehicle, turning is possible by controlling the rotation speed of the left and right drive wheels, so a steering mechanism is not required. This allows for a simplified structure and a lower floor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2002-220048 A (for example, paragraph 0012, Figures 1 and 2, etc.) Summary of the Invention [Problem to be solved by the invention]

[0004] However, the above-mentioned conventional technology has a problem in that it is difficult to achieve both a low vehicle floor and a sufficient load capacity. That is, in an automated guided vehicle that uses a two-wheel speed differential system, the weight of the vehicle body and cargo is mainly borne by the drive wheels. Therefore, if the diameter of the drive wheels is increased to ensure a sufficient load capacity, the vehicle height increases. On the other hand, if the diameter of the drive wheels is reduced to achieve a low floor, the load capacity decreases. Furthermore, if the width of the drive wheels is increased to ensure a sufficient load capacity, frictional resistance with the road surface increases, making turning difficult.

[0005] The present invention has been made to solve the above-mentioned problems, and aims to provide an unmanned guided vehicle that can achieve both a low floor of the vehicle body and a sufficient load capacity. [Means for solving the problem]

[0006] In order to achieve this object, the automatic guided vehicle of the present invention comprises a vehicle body on which a load is loaded, left and right drive wheels arranged approximately in the center of the vehicle body in the longitudinal direction and configured to be independently drivable, casters arranged on the vehicle body and configured to be rotatable in the horizontal direction, driven wheels that rotate as the vehicle travels, and a swing mechanism interposed between the drive wheels, the driven wheels, and the vehicle body, and supporting the drive wheels and the driven wheels so that they can swing relative to the vehicle body. The driven wheels are arranged on the left and right, and the swing mechanism includes left and right supports that support the drive wheels and the driven wheels, respectively, and left and right swing means that are arranged between the drive wheels and the driven wheels of the left and right supports and support the left and right supports so that they can swing relative to the vehicle body, and the drive wheels and the driven wheels are arranged side by side in the left and right direction of the vehicle body, and the left and right supports can swing around an axis oriented along the front-rear direction of the vehicle body. do. The automated guided vehicle of the present invention comprises a vehicle body on which a load is carried, left and right drive wheels arranged approximately in the center of the vehicle body in the longitudinal direction and configured to be independently drivable, and casters arranged on the vehicle body and configured to be swivelable in the horizontal direction, and further comprises driven wheels that rotate as the vehicle travels, and a swing mechanism interposed between the drive wheels and the driven wheels and the vehicle body and supporting the drive wheels and the driven wheels so that they can swing relative to the vehicle body, the swing mechanism comprising left and right support bodies and left and right swing shafts that pivotally support the left and right support bodies so that they can swing relative to the vehicle body, one of the left and right support bodies supporting the drive wheels and the driven wheels and also supporting the one support body. The oscillating shaft that supports the body is arranged between the drive wheel and the driven wheel supported by one of the supports, the other of the left and right supports supports the drive wheel on the left-right outer side of the vehicle body than the oscillating shaft that supports the other support, the axles of the drive wheels and the axles of the driven wheels are arranged in a direction along the left-right direction of the vehicle body, the left and right oscillating shafts are arranged in a direction along the fore-and-aft direction of the vehicle body, and the lower surface of a portion of the other support that is more inward in the left-right direction of the vehicle body than the oscillating shaft that supports the other support is connected to the upper surface of a portion of the one support that is more inward in the left-right direction of the vehicle body than the oscillating shaft that supports the one support. [Effects of the Invention]

[0007] Claim 1 and 6 The described automated guided vehicle is equipped with driven wheels that rotate as the vehicle moves, so the weight of the vehicle body and cargo can be distributed between the drive wheels and the driven wheels, allowing the diameters of the drive wheels and the driven wheels to be made smaller, thereby achieving both a low floor for the vehicle body and a sufficient load capacity.

[0008] However, according to claim 1, a swing mechanism is provided between the drive wheels and the vehicle body and supports the drive wheels and the driven wheels so that they can swing relative to the vehicle body, making it easier to ensure that both the drive wheels and the driven wheels are in contact with the road surface on uneven roads. This makes it possible to prevent the vehicle from becoming unable to travel due to a loss of wheel load on the drive wheels, or to prevent breakdowns due to the load being concentrated on the drive wheels.

[0009] Claim 1 According to the listed automated guided vehicle , followSince the driving wheels are arranged on the left and right, the number of driven wheels can be secured, and the weight of the vehicle body and cargo can be more effectively distributed among the driving wheels and driven wheels. This allows the diameters of the driving wheels and driven wheels to be made smaller, achieving both a low vehicle floor and a sufficient load capacity.

[0010] Furthermore, since the drive wheels and driven wheels are supported by left and right supports, respectively, and the left and right supports are supported by left and right swinging means so that they can swing relative to the vehicle body, the drive wheels and driven wheels on the left and right supports can be easily brought into contact with the road surface on uneven road surfaces, thereby preventing the vehicle from becoming unable to travel due to loss of wheel load on the drive wheels, and preventing breakdowns due to load concentration on the drive wheels.

[0011] Claim 2 According to the described automated guided vehicle, claims 1 In addition to the effects of the described automatic guided vehicle, the swinging means is configured as left and right swinging shafts arranged between the drive wheels and driven wheels of the left and right supports and supporting each of the left and right supports so that they can swing relative to the vehicle body, thereby stabilizing the swinging of the supports relative to the vehicle body.

[0012] Claim 3 According to the described automated guided vehicle, claims 2 In addition to the effects of the described automated guided vehicle, the axles of the driven wheels are arranged in a direction that runs along the left-right direction of the vehicle body, which simplifies the structure compared to, for example, a case where the driven wheels are able to rotate horizontally relative to the support body.

[0013] Claim 4 According to the described automated guided vehicle, claims 3 In addition to the effects of the above-described automated guided vehicle, the drive wheels are disposed on the outer side of the vehicle body in the lateral direction relative to the swing shaft, and the driven wheels are disposed on the inner side of the vehicle body in the lateral direction relative to the swing shaft, so that the left and right drive wheels can be spaced apart in the lateral direction of the vehicle body. This improves turning performance. Furthermore, for example, when switching from forward to reverse travel, the vehicle body can be prevented from meandering due to the rotation of the casters.

[0014] Claim5 According to the described automated guided vehicle, claims 4 In addition to the effects of the automated guided vehicle described above, the left and right swing shafts are disposed at approximately the center between the drive wheels and the driven wheels, so the loads borne by the drive wheels and the driven wheels in each of the left and right swing mechanisms can be equalized, which means that the drive wheels and the driven wheels can be configured from the same wheels, thereby reducing parts costs.

[0015] Claim 6 According to the listed automated guided vehicle , others The lower surface of a portion of one of the supports that is laterally inward of the pivot shaft supporting the other support is connected to the upper surface of a portion of one of the supports that is laterally inward of the pivot shaft supporting the other support, allowing the one support and the other support to be interlocked. This makes it easier for the left and right drive wheels and driven wheels to contact the road surface on uneven road surfaces. This prevents the drive wheels from losing wheel load, resulting in the vehicle becoming unable to travel, and prevents the drive wheels from failing due to concentrated load on the drive wheels. Furthermore, since the number of driven wheels can be reduced to one, component costs can be reduced and the vehicle's lateral dimensions can be reduced.

[0016] Claim 7 According to the described automated guided vehicle, claims 6 In addition to the effects of the automated guided vehicle described above, on one support, the drive wheels are disposed on the outer side of the vehicle body in the lateral direction relative to the swing shaft, and the driven wheels are disposed on the inner side of the vehicle body in the lateral direction relative to the swing shaft, so that the left and right drive wheels can be spaced apart in the lateral direction of the vehicle body. This improves turning performance. Furthermore, for example, when switching from forward to reverse travel, the vehicle body can be prevented from meandering due to the rotation of the casters.

[0017] Claim 8 According to the described automated guided vehicle, claims 7 In addition to the effects of the described unmanned guided vehicle, the distance between the driven wheels and the oscillating shaft is made larger than the distance between the drive wheels and the oscillating shaft, thereby reducing the difference in load between the left and right drive wheels and the load borne by the central driven wheel. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a side view of an automated guided vehicle according to a first embodiment of the present invention. [Figure 2] FIG. [Figure 3] FIG. 3 is a cross-sectional view of the automated guided vehicle taken along line III-III in FIG. [Figure 4] FIG. 10 is a bottom view of the automatic guided vehicle according to the second embodiment. [Figure 5] 5 is a cross-sectional view of the automated guided vehicle taken along line VV in FIG. 4. DETAILED DESCRIPTION OF THE INVENTION

[0019] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Fig. 1 is a side view of an automated guided vehicle 1 according to a first embodiment of the present invention, Fig. 2 is a bottom view of the automated guided vehicle 1, and Fig. 3 is a cross-sectional view of the automated guided vehicle 1 taken along line III-III in Fig. 1.

[0020] 1 to 3, the automated guided vehicle 1 is illustrated schematically to simplify the drawings and make them easier to understand. Spring casters 40 are not shown in Fig. 3. Arrows FB, UD, and LR in the drawings indicate the front-to-rear direction (travel direction), up-down direction, and left-to-right direction (width direction) of the automated guided vehicle 1, respectively. The same applies to Figs. 4 and 5.

[0021] As shown in Figures 1 to 3, the unmanned guided vehicle 1 comprises a vehicle body 10 on which cargo is loaded, left and right running devices 20 having drive wheels 23, left and right driven bodies 30 having driven wheels 33, spring casters 40 having wheels 44, left and right swinging mechanisms 50 interposed between the running devices 20 and the driven bodies 30 and the vehicle body 10, and a control device (not shown) that controls the drive motors 24 of the running devices 20, and is configured as an unmanned guided vehicle that can move forward, backward and turn by controlling the rotation speed of the left and right drive wheels 23.

[0022] The traveling device 20 comprises a seat 21 arranged on the bottom surface of the swing mechanism 50 (support body 51), a pair of forks 22 arranged on the seat 21 and facing each other at a predetermined distance, a drive wheel 23 rotatably supported between the pair of forks 22, and a drive motor 24 that imparts a rotational drive force to the drive wheel 23.

[0023] The driven body 30 comprises a seat 31 disposed on the bottom surface of the swing mechanism 50 (support body 51), a pair of forks 32 disposed on the seat 31 and facing each other at a predetermined distance, and a driven wheel 33 rotatably journaled between the pair of forks 32, and the driven wheel 33 rotates (is driven) as the vehicle travels. In this embodiment, the driven body 30 (seat 31 and forks 32) is fixed to the vehicle body 10 via the swing mechanism 50, and therefore the structure can be simplified compared to, for example, a case where the driven body 30 is rotatable horizontally relative to the vehicle body 10.

[0024] The spring caster 40 comprises a seat 41 arranged on the bottom surface of the vehicle body 10, a housing 42 configured to be rotatable horizontally relative to the seat 41, a pair of forks 43 rotatably supported at one end by the housing 42 and facing each other at a predetermined distance, a wheel 44 rotatably supported between the other ends of the pair of forks 43, and a spring 45 interposed between the housing 42 and the fork 43, and is configured as a swivel caster in which the axle of the wheel 44 is positioned away (eccentrically) from the center of rotation of the housing 42.

[0025] The spring caster 40 is capable of changing the distance between the vehicle body 10 and the wheel 44 by elastic deformation (expansion and contraction) of the spring 45. Therefore, even if the road surface G is undulating in the fore-and-aft direction (direction of arrow FB) of the vehicle body 10 (when the road surface G shown in FIG. 1 forms hills and valleys), the drive wheel 23 can easily contact the ground.

[0026] The swing mechanism 50 comprises a support body 51 in which the seat 21 of the running device 20 is arranged at one end side in the left-right direction (arrow LR direction) (in this embodiment, on the outside in the width direction of the vehicle body 10) and the seat 31 of the driven body 30 is arranged at the other end side in the left-right direction (arrow LR direction) (in this embodiment, on the inside in the width direction of the vehicle body 10), a swing shaft 52 arranged at approximately the center of the support body 51 in the left-right direction (arrow LR direction), and a stay 53 that supports the swing shaft 52 so that it can swing and is arranged on the bottom surface of the vehicle body 10 and faces the vehicle body 10 at a distance in the fore-aft direction (arrow FB direction), and is configured to be swingable relative to the vehicle body 10.

[0027] A pair of rocking mechanisms 50 are arranged side by side in the left-right direction (direction of arrows LR) of the vehicle body 10, and the pair of (left and right) rocking mechanisms 50 are disposed at a position that is approximately the center in the fore-aft direction (direction of arrows FB) of the vehicle body 10. Note that the pair of (left and right) rocking mechanisms 50 are disposed at positions that are symmetrical with respect to an imaginary line connecting the rotation centers of the front and rear spring casters 40 in a plan view (see FIG. 2).

[0028] The swing shaft 52 of the swing mechanism 50 is disposed in a direction along the front-rear direction (direction of arrow FB) of the vehicle body 10, and the axles of the drive wheels 23 and the driven wheels 33 are disposed in a direction along the left-right direction (direction of arrow LR) of the vehicle body 10. The drive wheels 23 and the driven wheels 33 are disposed in positions where the axles are aligned in a straight line in a plan view (see FIG. 2).

[0029] According to the automatic guided vehicle 1 of this embodiment, since it is provided with the driven wheels 33, the weight of the vehicle body 10 and the cargo can be distributed to the drive wheels 23 and the driven wheels 33, and accordingly the diameters of the drive wheels 23 and the driven wheels 33 can be reduced without increasing their widths. This makes it possible to achieve both a low floor of the vehicle body 10 and a sufficient load capacity.

[0030] Here, if the drive wheels 23 and the driven wheels 33 (more specifically, the running device 20 and the driven body 30) are arranged directly on the vehicle body 10, if the road surface G has undulations along the left-right direction (arrow LR direction) of the vehicle body 10 (the road surface G shown in Figure 3 forms mountains and valleys), it will be difficult for the drive wheels 23 or the driven wheels 33 to make contact with the ground.

[0031] In contrast, according to the automated guided vehicle 1 of this embodiment, the swing mechanism 50 is interposed between the vehicle body 10 and the drive wheels 23 and driven wheels 33, and the drive wheels 23 and driven wheels 33 are supported to be swingable relative to the vehicle body 10. Therefore, even on a road surface G that is uneven in the left-right direction of the vehicle body 10, the swing of the swing mechanism 50 (support body 51) makes it easier to create a state in which both the drive wheels 23 and the driven wheels 33 come into contact with the road surface G. This makes it possible to prevent the drive wheels 23 from becoming unable to travel due to a loss of wheel load, and to prevent the drive wheels 23 and the drive motor 24 from being damaged or broken due to a load being concentrated on the drive wheels 23.

[0032] In this embodiment, in each of the left and right swing mechanisms 50, the drive wheels 23 are disposed on the outside of the swing shaft 52 in the left-right direction of the vehicle body 10 (in the direction of the arrows LR), and the driven wheels 33 are disposed on the inside of the swing shaft 52 in the left-right direction of the vehicle body 10, so that the distance between the left and right drive wheels 23 in the left-right direction of the vehicle body 10 can be secured (larged). This improves turning performance. Also, for example, when the traveling direction is switched from forward to reverse, the vehicle body 10 can be prevented from meandering as the spring casters 40 turn.

[0033] In this embodiment, the swing shaft 52 is disposed in a position that is approximately the center between the axles of the drive wheels 23 and the driven wheels 33 in a plan view (a position where the distance in the left-right direction (direction of arrows LR) of the vehicle body 10 is approximately the same) (see FIG. 2). Therefore, in each of the left and right swing mechanisms 50, the load borne by the drive wheels 23 and the load borne by the driven wheels 33 can be equalized. Therefore, the drive wheels 23 and the driven wheels 33 can be configured from the same wheel (rubber tire in this embodiment), thereby reducing parts costs accordingly.

[0034] Next, an automated guided vehicle 201 according to a second embodiment will be described with reference to Figures 4 and 5. The automated guided vehicle 1 according to the first embodiment has two driven wheels 33, but the automated guided vehicle 201 according to the second embodiment has one driven wheel 33.

[0035] Fig. 4 is a bottom view of an automated guided vehicle 201 in the second embodiment, and Fig. 5 is a cross-sectional view of the automated guided vehicle 201 taken along line VV in Fig. 4. Note that the same parts as those in the first embodiment described above are given the same reference numerals, and their description will be omitted.

[0036] As shown in Figures 4 and 5, the unmanned guided vehicle 201 comprises a vehicle body 10, left and right running devices 20, one follower 30, spring casters 40, left and right swing mechanisms 250A, 250B interposed between the running devices 20 and the follower 30 and the vehicle body 10, and a control device (not shown) that controls the running devices 20 (drive motor 24).

[0037] The swing mechanism 250A has a first support 251a in which the seat 21 of the running device 20 is arranged at one end side (in this embodiment, on the outside of the width direction of the vehicle body 10) in the left-right direction (arrow LR direction), and the seat 31 of the driven body 30 is arranged at the other end side (in this embodiment, on the inside of the width direction of the vehicle body 10) in the left-right direction (arrow LR direction), and the swing shaft 52 arranged on the first support 251a is journaled on a stay 53, so that it can swing relative to the vehicle body 10.

[0038] The swing mechanism 250B has a second support 251b in which the seat 21 of the running device 20 is arranged at one end side (in this embodiment, outside the width direction of the vehicle body 10) in the left-right direction (direction of arrow LR), and the swing shaft 52 arranged on the second support 251b is journaled on a stay 53, so that it can swing relative to the vehicle body 10.

[0039] The swing mechanisms 250A, 250B are arranged side by side in the left-right direction (arrow LR direction) of the vehicle body 10, and the swing mechanisms 250A, 250B are disposed at a position that is approximately the center of the vehicle body 10 in the front-rear direction (arrow FB direction).

[0040] As in the first embodiment, the swing shaft 52 is disposed in a direction along the front-rear direction (direction of arrow FB) of the vehicle body 10, and the axles of the drive wheels 23 and the driven wheels 33 are disposed in a direction along the left-right direction (direction of arrow LR) of the vehicle body 10. The drive wheels 23 and the driven wheels 33 are disposed in positions where the axles are aligned in a straight line in a plan view (see FIG. 4).

[0041] In a plan view, the driven wheel 33 is positioned so that the tire center line coincides with an imaginary line connecting the rotation centers of the front and rear spring casters 40, and the drive wheel 23 and the oscillating shaft 52 are positioned so as to be symmetrical with respect to the imaginary line connecting the rotation centers of the front and rear spring casters 40 (see Figure 4).

[0042] The first support body 251a and the second support body 251b overlap each other in the up-down direction (arrow UD direction) at portions that are on the inside in the left-right direction (arrow LR direction) of the vehicle body 10. That is, the lower surface of a portion of the second support body 251b that is on the inside in the left-right direction of the vehicle body 10 (left side in FIG. 5) of the swing shaft 52 is slidably connected to the upper surface of a portion of the first support body 251a that is on the inside in the left-right direction of the vehicle body 10 (right side in FIG. 5) of the swing shaft 52, and when one of the first support body 251a or the second support body 251b swings, the other can also swing in conjunction with the swing of the one.

[0043] A protrusion is provided on the underside of the second support body 251b on the other end side (in the width direction of the vehicle body 10 in this embodiment) in the left-right direction (direction of arrows LR), and the tip of the protrusion is placed on the upper surface of the first support body 251a, thereby connecting the first support body 251a and the second support body 251b. This makes it possible to reduce resistance when the protrusion of the second support body 251b slides on the upper surface of the first support body 251a in the left-right direction of the vehicle body 10 (direction of arrows LR).

[0044] According to the automated guided vehicle 201 of this embodiment, as in the first embodiment described above, by providing the driven wheels 33, the weight of the vehicle body 10 and cargo can be distributed to the drive wheels 23 and the driven wheels 33, and the diameters of the drive wheels 23 and the driven wheels 33 can be reduced accordingly. This makes it possible to achieve both a low floor of the vehicle body 10 and a sufficient load capacity.

[0045] Furthermore, even if the road surface G is undulating in the left-right direction (direction of arrows LR) of the vehicle body 10 (the road surface G shown in FIG. 5 has mountains and valleys), the swinging of the swinging mechanisms 250A, 250B (first support body 251a and second support body 251b) can easily bring the left and right drive wheels 23 and the central driven wheel 33 into contact with the road surface G. This can prevent the drive wheels 23 from losing wheel load, which can cause the vehicle to become unable to travel, and can prevent the load from concentrating on the drive wheels 23, which can cause damage or malfunction to the drive wheels 23 or the drive motor 24.

[0046] In particular, according to the automatic guided vehicle 201 of this embodiment, the number of driven wheels 33 can be reduced to one, which reduces the cost of parts and reduces the dimension of the vehicle body 10 in the left-right direction (arrow LR direction).

[0047] In this embodiment, in the swing mechanism 250A, the drive wheels 23 are disposed on the outer side of the swing shaft 52 in the left-right direction (direction of arrows LR) of the vehicle body 10, and the driven wheels 33 are disposed on the inner side of the swing shaft 52 in the left-right direction of the vehicle body 10, so that the distance between the left and right drive wheels 23 in the left-right direction of the vehicle body 10 can be secured (larged). This makes it possible to improve turning performance. Also, for example, when the traveling direction is changed from forward to reverse, it is possible to prevent the vehicle body 10 from meandering as the spring casters 40 turn.

[0048] In this embodiment, the position where the protrusion of the second support 251b is placed on the upper surface of the first support 251a is set to a position that overlaps with the tire center line of the driven wheel 33 (see FIG. 5). In addition, in a plan view, the axle of the driven wheel 33 is disposed at a position that is approximately the center between the left and right swing shafts 52 (a position where the distance in the left-right direction (arrow LR direction) of the vehicle body 10 is approximately the same), and the distance between the axle of the drive wheel 23 and the swing shaft 52 is set to be approximately twice the distance between the axle of the drive wheel 23 and the swing shaft 52 (see FIG. 4).

[0049] This makes it possible to equalize the load borne by the left and right drive wheels 23 and the load borne by the central driven wheel 33. Therefore, the drive wheels 23 and the driven wheels 33 can be configured from the same wheel (rubber tire in this embodiment), thereby reducing parts costs accordingly.

[0050] The present invention has been described above based on an embodiment, but the present invention is not limited to the above embodiment, and it can be easily inferred that various improvements and modifications are possible within the scope of the present invention.

[0051] The numerical values ​​given in the above embodiment are merely examples, and it is of course possible to adopt other numerical values. For example, in the above second embodiment, the distance between the axle of the driven wheel 33 and the swing shaft 52 is set to approximately twice the distance between the axle of the drive wheel 23 and the swing shaft 52, but the numerical value may be smaller than twice or larger than twice.

[0052] In the first embodiment, the rocker shaft 52 is disposed at a position that is approximately in the center between the axles of the drive wheels 23 and the driven wheels 33 in a plan view. However, the position of the rocker shaft 52 may be changed from the approximately central position. This allows the distribution of the load borne by the drive wheels 23 and the driven wheels 33 to be changed.

[0053] In this case, the wheel (e.g., driven wheel 33) on the side where the distance to the oscillating shaft 52 is greater will bear less load, so it may have a smaller outer diameter than the wheel (drive wheel 23) on the side where the distance to the oscillating shaft 52 is smaller.

[0054] In the second embodiment, the swing mechanism 250B may be omitted. That is, one of the left and right drive wheels 23 (traveling device 20) may be directly disposed on the vehicle body 10, and the other drive wheel 23 (traveling device 20) may be disposed on the swing mechanism 250A together with one driven wheel 33 (follower 30).

[0055] In each of the above embodiments, the driving wheels 23 are arranged on the outside of the driven wheels 33 in the left-right direction of the vehicle body 10 (in the direction of the arrow LR), but the opposite arrangement (the driving wheels 23 are arranged on the inside of the driven wheels 33 in the left-right direction of the vehicle body 10) may also be used.

[0056] In each of the above embodiments, the case where the oscillating shaft 52 is arranged on the support body 51 and is pivotally supported by the stay 53 so as to be able to oscillate has been described. However, the oscillating shaft 52 may also be arranged on the stay 53 and is pivotally supported by the support body 51 so as to be able to oscillate.

[0057] In each of the above embodiments, a damping mechanism that applies a damping force to the swing mechanism 50, 250A, 250B may be added. Examples of the damping mechanism include a shock absorber interposed between the vehicle body 10 and the support 51, the first support 251a, and the second support 251b, and a rotary damper interposed between the swing shaft 52 and the stay 53. This can improve the running stability of the automatic guided vehicle 1, 201.

[0058] An elastic body (for example, a cylindrical rubber bushing) made of a rubber-like elastic body may be interposed between the outer peripheral surface of the swing shaft 52 and the inner peripheral surface of the stay 53. By deformation of the elastic body (rubber bushing), it is possible to add a damping mechanism while allowing the support body 51, the first support body 251a, and the second support body 251b to swing relative to the vehicle body 10.

[0059] Furthermore, the swing shaft 52 may be omitted and an elastic body (swing means) may be interposed between the lower surface of the vehicle body 10 and the upper surfaces of the support body 51, the first support body 251a, and the second support body 251b, or the swing shaft 52 may be omitted and an elastic body (swing means) may be interposed between the support body 51, the first support body 251a, and the second support body 251b and the stay 53. In these cases as well, a damping mechanism can be added while allowing the support body 51, the first support body 251a, and the second support body 251b to swing relative to the vehicle body 10 by deformation of the elastic body.

[0060] In the above embodiments, the case where the driven wheel 33 (follower 30) is arranged on the support body 51 or the first support body 251a so as not to be able to turn (the seat 31 is fixed to the support body 51 or the first support body 251a) has been described. However, the driven wheel 33 (follower 30) may be arranged on the support body 51 or the first support body 251a so as to be able to turn horizontally. In other words, the driven wheel 33 (follower 30) may be configured as a swivel caster. In this case, it is possible to reduce resistance when the vehicle turns.

[0061] In the above first embodiment, the oscillating shaft 52 is arranged in a direction along the fore-and-aft direction (direction of arrow FB) of the vehicle body 10, and the drive wheel 23 and the driven wheel 33 are arranged on the support body 51 with the oscillating shaft 52 sandwiched between them in the left-right direction (direction of arrow LR) of the vehicle body 10. However, the configuration may also be such that the oscillating shaft 52 is arranged in a direction along the left-and-right direction (direction of arrow LR) of the vehicle body 10 (i.e., parallel to the axle of the drive wheel 23), and the drive wheel 23 and the caster are arranged on the support body 51 with the oscillating shaft 52 sandwiched between them in the fore-and-aft direction (direction of arrow FB) of the vehicle body 10.

[0062] In this case, the drive wheel 23 is positioned approximately in the center of the front-rear direction (arrow FB direction) of the vehicle body 10 in a plan view, and the caster disposed on the support body 51 is positioned on one side of the vehicle body 10 in the front-rear direction. The caster disposed on the vehicle body 10 is disposed on the other side of the vehicle body 10 in the front-rear direction in a plan view. These casters do not need to be spring casters 40, and may be swivel casters that can swivel horizontally. Furthermore, only one caster wheel may be disposed on the vehicle body 10.

[0063] With an automated guided vehicle configured in this manner, three-point support is provided, which makes it easy for the drive wheels 23 to contact the ground even when the road surface G is uneven in the fore-and-aft direction (direction of arrow FB) of the vehicle body 10 (when the road surface G shown in FIG. 1 has hills and valleys). Note that the distance between the axle of the caster disposed on the support body 51 and the swing shaft 52 is greater than the distance between the axle of the drive wheels 23 and the swing shaft 52 in a plan view. [Explanation of symbols]

[0064] 1,201 automated guided vehicles 10. Body 23 Drive wheels 33 Driven wheels 40 Spring Caster (Caster) 50 Swing mechanism 51 Support 52 Oscillating shaft 250A, 250B swing mechanism 251a First support (one support) 251b Second support (other support) Arrow FB forward / backward Arrow UD Up and Down Arrows LR left and right

Claims

1. An automated guided vehicle (AGV) is provided with a vehicle body on which a load is carried, left and right drive wheels arranged approximately in the center of the vehicle body in the longitudinal direction and configured to be independently drivable, and casters arranged on the vehicle body and configured to be rotatable in a horizontal direction, a driven wheel that rotates as the vehicle travels; and a swing mechanism that is interposed between the drive wheel and the driven wheel and the vehicle body and that supports the drive wheel and the driven wheel so that they can swing relative to the vehicle body; The driven wheels are disposed on the left and right sides, the swing mechanism includes left and right supports that support the drive wheels and the driven wheels, respectively, and left and right swing means that are disposed between the drive wheels and the driven wheels of the left and right supports and support the left and right supports so that they can swing relative to the vehicle body, The drive wheels and the driven wheels are arranged side by side in the left-right direction of the vehicle body, The left and right supports are capable of swinging about axes oriented along the longitudinal direction of the vehicle body.

2. the swinging means are configured as left and right swinging shafts that are disposed between the drive wheels and the driven wheels of the left and right supports and pivotally support the left and right supports so that they can swing relative to the vehicle body, The axles of the drive wheels are arranged in a direction along the left-right direction of the vehicle body, 2. The automated guided vehicle according to claim 1, wherein the left and right swing shafts are disposed in a direction parallel to the longitudinal direction of the vehicle body.

3. 3. The automated guided vehicle according to claim 2, wherein the axles of the driven wheels are disposed in a direction parallel to the left-right direction of the vehicle body.

4. 4. The automated guided vehicle according to claim 3, wherein the drive wheels are disposed on the outer side of the vehicle body in the left-right direction relative to the swing shaft, and the driven wheels are disposed on the inner side of the vehicle body in the left-right direction relative to the swing shaft.

5. 5. The automated guided vehicle according to claim 4, wherein the swing shaft is disposed at a position substantially in the center between the driving wheels and the driven wheels.

6. An automated guided vehicle (AGV) is provided with a vehicle body on which a load is carried, left and right drive wheels arranged approximately in the center of the vehicle body in the longitudinal direction and configured to be independently drivable, and casters arranged on the vehicle body and configured to be rotatable in a horizontal direction, a driven wheel that rotates as the vehicle travels; and a swing mechanism that is interposed between the drive wheel and the driven wheel and the vehicle body and that supports the drive wheel and the driven wheel so that they can swing relative to the vehicle body; the swing mechanism includes left and right support bodies and left and right swing shafts that pivotally support the left and right support bodies so that they can swing relative to the vehicle body, one of the left and right supports supports the drive wheel and the driven wheel, and the swing shaft supporting the one support is disposed between the drive wheel and the driven wheel supported by the one support, the other of the left and right supports supports the drive wheel on the outer side in the left-right direction of the vehicle body than the swing shaft that pivotally supports the other support, the axles of the drive wheels and the axles of the driven wheels are disposed along the left-right direction of the vehicle body, The left and right swing shafts are disposed in a direction along the front-rear direction of the vehicle body, an underside of a portion of the other support body that is located laterally inward of the vehicle body relative to the oscillating shaft that supports the other support body, connected to an upper surface of a portion of the one support body that is located laterally inward of the oscillating shaft that supports the one support body.

7. 7. The automated guided vehicle according to claim 6, wherein, on one of the supports, the drive wheels are arranged on the outer side of the vehicle body in the left-right direction relative to the swing shaft, and the driven wheels are arranged on the inner side of the vehicle body in the left-right direction relative to the swing shaft.

8. 8. The automated guided vehicle according to claim 7, wherein the distance between the driven wheels and the swing shaft is greater than the distance between the drive wheels and the swing shaft.

Images