Cart towing vehicle

Abstract

Provided is a towing vehicle which has a towing device for towing a cart disposed at the rear thereof, and which can easily enclose and restrain the cart when the cart is being towed, and release the cart from the towing vehicle, using an extremely simple mechanism. The towing device is an unmanned conveying vehicle not intended to be ridden on by an operator, wherein: the towing device does not have running driving wheels; the towing device is provided with a cart enclosing bar including two side bars that run along each side of the cart and two rear bars that are continuous with the side bars and that run inward from the corners thereof at the rear of the cart; end portions of the two side bars on the towing vehicle side are each attached to the towing device, and tip ends of each of the two rear bars can move between an inside position and an outside position at the rear of the cart; when the cart is being released, the tip ends of each of the two rear bars move to the outside positions at the rear of the cart, enabling the cart to be released from the cart enclosing bar; and when the cart is being towed, the tip ends of each of the two rear bars move to the inside positions at the rear of the cart to surround the cart along the inside thereof, from the sides of the cart and the corner portions at the rear of the cart, and the rear bars push the cart from the rear as the towing vehicle progresses, thereby enabling the cart to be towed in the direction of progress.

Description

dolly towing vehicle

[0001] The present invention relates to a towing vehicle having a towing device disposed at the rear for towing a cart used in commercial facilities, logistics facilities, etc.

[0002] Various carts are used to transport goods and packages in commercial facilities, logistics facilities, etc. These carts are often pushed by hand, but in recent years, to alleviate labor shortages, attempts have been made to use towing vehicles such as unmanned automated guided vehicles (AGVs) to tow these carts and transport them to their destinations.

[0003] Many such towing means and towing methods have been proposed in recent years (see Patent Documents 1 to 9). However, these conventionally proposed means for connecting the towed cart to a towing vehicle such as an automated guided vehicle use special connection methods such as pin connections or clamp connections, which require changes to the shape of the connection part depending on the shape of the towed cart, making it difficult to tow various shapes of carts and resulting in low versatility. In particular, when the towed cart is in the shape of a flatbed truck, there are essentially no hooking or clamping parts, making it difficult to create a simple and safe connection.

[0004] Furthermore, the conventionally proposed means for towing a bogie are based on the premise that the bogie and towing vehicle are coupled together, and therefore, when releasing the bogie from the towing vehicle, a special coupling state must be released, which is an extremely complicated and time-consuming process.

[0005] In response to this problem, the applicant has proposed a towing vehicle that can safely restrain and tow a bogie in various configurations without directly connecting the towing vehicle and the bogie by arranging a towing device for towing the bogie at the rear of the towing vehicle and enclosing both sides and each rear corner of the bogie with a bogie encirclement bar extending rearward from the towing device (see Patent Documents 10 and 11). These towing vehicles enclose and restrain the bogie during towing, and release the bogie from the towing vehicle by moving the two side bars of the bogie encirclement bar closer or farther apart in the width direction, or by moving the entire bogie encirclement bar between an upper position and a lower horizontal position with the towing vehicle side as a fulcrum.

[0006] However, these towing vehicles require the two long side bars of the bogie encirclement bar to be moved widthwise apart or the entire bogie encirclement bar to be moved between upper and lower positions in order to encircle and release the bogie, making the process extremely cumbersome and, even when automated, posing the problem of mechanical complexity.

[0007] JP 2021-70420 A JP 2019-131046 A JP 2017-100575 A JP 2016-150692 A JP 2016-150691 A JP 2015-131591 A JP 2014-210528 A JP 2011-102076 A JP 2009-113650 A Japanese Patent No. 7251004 A Japanese Patent No. 7289382 A

[0008] The present invention was devised to solve the above-mentioned problems of the prior art, and its object is to provide a towing vehicle having a towing device disposed at the rear for towing a bogie, which can easily enclose and restrain the bogie when towing and release the bogie from the towing vehicle using an extremely simple mechanism.

[0009] As a result of extensive research into achieving the above-mentioned object, the inventor discovered that in a towing vehicle having a towing device located at the rear for towing a bogie, by providing two side bars that can each fit along each side of the bogie as bogie encirclement bars extending rearward from the towing device, and two rear bars that are continuous with these and can each fit along the inward from each corner of the rear of the bogie, and by configuring the tips of each of the two rear bars to be movable between an inner position and an outer position at the rear of the bogie, when the tips are in the inner position the bogie can be enclosed and restrained and towed, and when the tips are in the outer position the bogie can be released from the bogie encirclement bars of the towing vehicle, and thus the invention was completed.

[0010] That is, the present invention was completed based on the above findings and has the following configurations (1) to (7): (1) A towing vehicle having a towing device disposed at the rear for towing a carriage, the towing vehicle being an unmanned guided vehicle not intended for an operator to ride on, the towing device having no running drive wheels, the towing device having carriage surrounding bars including two side bars that can respectively fit along each side of the carriage, and two rear bars that are continuous with the side bars and can respectively fit along the inside from each corner of the rear of the carriage, the towing vehicle-side ends of the two side bars being attached to the towing device, and the tips of the two rear bars being movable between an inside position and an outside position at the rear of the carriage. (2) A towing vehicle as described in (1), characterized in that when the bogie is released without being towed, the tips of each of the two rear bars move to an outer position at the rear of the bogie, thereby releasing the bogie out of the bogie encirclement bar, and when the bogie is to be encircled and towed, the tips of each of the two rear bars move to an inner position at the rear of the bogie, thereby encircling the bogie from the inside corners of the side and rear of the bogie, and as the towing vehicle moves forward with the bogie surrounded, the rear bars of the bogie encirclement bar push the bogie from the rear in the direction of travel, thereby towing the bogie in the direction of travel. (3) A towing vehicle as described in (1), characterized in that each of the two rear bars is attached to each of the two side bars so as to be horizontally movable in the width direction of the towing vehicle, and this horizontal movement allows the tip of each of the two rear bars to move between an inner position and an outer position at the rear of the bogie.(4) The towing vehicle described in (1), characterized in that each of the two rear bars is attached to each of the two side bars in a manner that allows them to swing open like hinged doors so that the tips of the two rear bars can move between a closed position facing each other in the width direction of the towing vehicle and an open position facing toward the rear of the towing vehicle, and this swing-open movement allows the tips of the two rear bars to move between a position on the inside of the rear of the bogie and a position on the outside. (5) The towing vehicle described in (1), characterized in that each of the two side bars is movable in the width direction of the towing vehicle so that they can move toward or away from each other while remaining parallel to each other. (6) The towing vehicle described in (1), characterized in that the towing device is detachable from the towing vehicle. (7) The towing vehicle described in (1), characterized in that the bogie is a flatbed truck, a six-wheeled truck, or a cage truck.

[0011] The towing vehicle of the present invention has a towing device at its rear for towing a bogie, and two side bars extending rearward from the towing device as bogie encirclement bars that can fit along each side of the bogie, and two rear bars that are continuous with the side bars and can fit along each corner of the rear of the bogie from the rear corner to the inside, and the tips of the two rear bars are movable between an inner position and an outer position at the rear of the bogie, so that simply moving the tips of the two rear bars makes it extremely easy to encircle and restrain the bogie when towing and to release the bogie from the towing vehicle.Furthermore, since the bogie can be enclosed and restrained and released by moving only the tips of the two rear bars without moving the entire bogie encirclement bar, these operations are not cumbersome even when performed manually, and can be automated with a simple mechanism.

[0012] [Amendment under Rule 91 20.06.2024] (a) Schematic plan view, (b) schematic side view, (c) schematic perspective view, and (d) schematic rear view of an example of a tractor of the present invention in which the tips of each of the two rear bars are in an inward position. (a) Schematic plan view, (b) schematic side view, (c) schematic perspective view, and (d) schematic rear view of an example of a tractor of the present invention in which the tips of each of the two rear bars are in an outward position. (a) Schematic plan view, (b) schematic side view, and (c) schematic perspective view of a tractor of the present invention in which the tips of each of the two rear bars are in an inward position at the rear of the tractor to enclose and restrain a dolly. (a) Schematic plan view, (b) schematic side view, and (c) schematic perspective view of a tractor of the present invention in which the tips of each of the two rear bars are in an outward position at the rear of the tractor to release the dolly. 6A and 6B show (a) a schematic plan view, (b) a schematic side view, and (c) a schematic perspective view of a towing vehicle of the present invention with the tips of the two rear bars in the outboard position and the dolly being removed from the towing device.

[0023] Fig. 6B is an explanatory diagram of an example of a rear bar movement mechanism of a towing vehicle of the present invention, showing (a) a schematic view from the rear when the tips of the rear bars are in the inboard position, (b) a schematic view of the mechanism for (a), (c) a schematic view from the rear when the tips of the rear bars are in the outboard position, and (d) a schematic view of the mechanism for (c).

[0024] Fig. 6B is an explanatory diagram of another example of a rear bar movement mechanism of a towing vehicle of the present invention, showing (a) a schematic view when the tips of the rear bars are in the inboard position, (b) a schematic view when the tips of the rear bars are in the outboard position, and (c) a schematic view of the mechanism for horizontally moving the rear bar. (a) A schematic plan view of another example of the rear bar movement mechanism of the towing vehicle of the present invention when the tip of the rear bar is in the inner position, (b) A schematic side view of (a), (c) A schematic plan view of (a) when the tip of the rear bar is in the outer position, and (d) A schematic side view of (c). Three schematic views of a flatbed truck that is surrounded and towed by the towing device of the towing vehicle of the present invention are shown.

[0013] Typical embodiments of a towing vehicle and a towing device disposed at the rear of the towing vehicle according to the present invention will be described below with reference to the drawings, but the present invention is not limited thereto.

[0014] The towing vehicle of the present invention is generally used in industries that handle sorting and delivery of goods, by disposing a towing device at the rear of the towing vehicle and towing a dolly with the towing device. The towing vehicle body is not particularly limited as long as it can tow the dolly under its own power, but an automated guided vehicle (AGV) is preferably used, for example. The towing device is preferably configured to be detachable from the towing vehicle for ease of storage and maintenance. The dolly is not particularly limited as long as it can carry goods and has running wheels on its bottom, but a dolly with an overall rectangular planar bottom on which the goods are placed is preferably used, for example, a flatbed truck, a six-wheeled truck, or a basket truck. As the flatbed truck, for example, the one shown in FIG. 10 is used.

[0015] Figures 1 and 2 are (a) a schematic plan view, (b) a schematic side view, (c) a schematic perspective view, and (d) a schematic rear view of an example of a towing vehicle of the present invention, with the tips of each of the two rear bars in an inward position in Figure 1 and the tips of each of the two rear bars in an outward position in Figure 2. Figure 3 shows the towing vehicle of Figure 1 in a state where a dolly can be enclosed and restrained and towed, and Figure 4 shows the towing vehicle of Figure 2 in a state where the dolly can be released. Figure 5 shows the state where the dolly is being removed from the towing vehicle of Figure 2. Figures 3 to 5 (a) to (c) are (a) a schematic plan view, (b) a schematic side view, and (c) a schematic perspective view.

[0016] In the drawings, reference numeral 1 denotes the towing vehicle of the present invention, which is preferably an automated guided vehicle (AGV) with driving wheels. The automated guided vehicle (AGV) is preferably not intended for an operator to ride on. Reference numeral 2 denotes a carriage, the bottom of which is preferably rectangular. Reference numeral 3 denotes a traction device for towing the carriage 2, which is disposed at the rear of the towing vehicle 1. The traction device 3 preferably does not have driving wheels. The traction device 3 has a carriage encircling bar 4 extending rearward from its rear. The carriage encircling bar 4 is essentially intended to encircle the carriage 2 from each side and each rear corner to the inside. To perform this function, the carriage encircling bar 4 includes two side bars 5 that can fit along each side of the carriage 2, and two rear bars 6 that are formed contiguous with the side bars 5 and can fit along each rear corner of the carriage 2, respectively. The towing vehicle 1 of the present invention is not directly connected to the bogie 2, so that the bogie 2 can be easily towed even if the bogie has various shapes, and there is no need to provide a towing means on the bogie itself.

[0017] The greatest feature of the towing vehicle 1 of the present invention is that the tip of each of the two rear bars 6 of the bogie encirclement bar 4 is configured to be movable between an inner position and an outer position at the rear of the bogie 2 when viewed in a state where the bogie 2 is surrounded by the bogie encirclement bar 4. It is preferable that the two rear bars 6 can be fixed at the inner position and the outer position, respectively.

[0018] Here, the "inner position" at the rear of the bogie 2 refers to a position where, when the two side bars 5 are viewed along the sides of the bogie 2 (in contact with or close to the sides), the tips of each of the two rear bars 6 extend inward from the rear corners of the bogie 2. When the bogie encircling bars 4 are in this inner position, they can surround the bogie 2 along the inside from each side of the bogie 2 and each of the rear corners connected to them. When the towing vehicle 1 advances in the direction of travel while the bogie 2 is surrounded, the rear bars 6 of the bogie encircling bars 4 push the bogie 2 from the rear in the direction of travel, thereby towing the bogie 2 in the direction of travel. In this inner position, it is preferable that the tips of each of the two rear bars 6 protrude inward from the inner edges of the two side bars 5, and that the distance between the tips of the two rear bars 6 is shorter than the width of the rear of the bogie 2. For example, the rear bars 6 in FIGS. 1 and 3 correspond to this inner position.

[0019] Furthermore, the outer position at the rear of the bogie 2 refers to a position where the tip of each of the two rear bars 6 is not at the rear of the bogie 2 (i.e., a position where each of the two rear bars 6 is not directly behind the bogie 2) when viewed with the two side bars 5 along the sides of the bogie 2 (in contact with or close to the sides), and when the bogie 2 is in this outer position, it can be removed and released from the bogie encircling bars 4. In this outer position, it is preferable that the tip of each of the two rear bars 6 does not protrude inward beyond the inner edges of the two side bars 5. This outer position corresponds to the rear bars 6 in Figures 2, 4 and 5, for example.

[0020] When towing a bogie 2 with the towing device 3 of the present invention, first, the tips of the two rear bars 6 of the bogie encircling bar 4 are set to the outward position as shown in Fig. 2. In this state, the bogie 2 is introduced from the rear of the towing device 3 as shown in Fig. 4. Then, the tips of the two rear bars 6 are set to the inward position as shown in Fig. 3 to surround the bogie 2, thereby restraining the bogie 2 to the towing vehicle 1. Then, by moving the towing vehicle 1 in the forward direction with the bogie 2 surrounded and restrained, the rear bars 6 of the bogie encircling bar 4 push the bogie 2 from the rear in the forward direction, thereby towing the bogie 2 in the forward direction. When it is desired to release the bogie 2 without towing it, the tips of the two rear bars 6 of the bogie encircling bar 4 are moved from the inner position as shown in Fig. 3 to the outer position as shown in Fig. 4. Then, the bogie 2 is removed to the rear of the towing vehicle 1 as shown in Fig. 5, thereby releasing the bogie 2 from the bogie encircling bar 4. In the towing vehicle of the present invention, the encircling and restraining of the bogie 2 for towing and the release of the bogie 2 from the towing vehicle 1 can be achieved by simply moving the tip of the rear bar 6, which is part of the bogie encircling bar 4, between an inner position and an outer position at the rear of the bogie 2 without moving the entire bogie encircling bar 4, making the operation extremely simple and reliable.

[0021] In the towing vehicle 1 of the present invention, the bogie encircling bar 4 is preferably configured so that each of the two side bars 5 can move toward or away from each other while remaining parallel to each other in the width direction of the towing vehicle 1. Such a configuration can be achieved, for example, by means such as those disclosed in Patent Documents 9 and 10. This allows the distance between the two side bars 5 of the bogie encircling bar 4 to be quickly adjusted when the width of the bogie 2 being towed changes, so that the two side bars 5 can be properly aligned along each of the two sides of the bogie 2.

[0022] The two side bars 5 of the bogie encircling bar 4 preferably extend in the direction of travel long enough to fit along the entire sides of the bogie 2. It is also preferable to provide two front bars on the sides of the two side bars 5 in the direction of travel that can fit along each corner of the front of the bogie 2. This allows the bogie 2 to be firmly restrained, ensuring stability of the bogie 2 when towing. It is preferable that each of the two side bars 5 has a wheel on the floor surface behind it.

[0023] In the towing vehicle 1 of the present invention, the means for allowing the leading ends of each of the two rear bars 6 to move between inner and outer positions at the rear of the bogie 2 is not particularly limited as long as the object of the present invention is achieved, and conventionally known methods and mechanisms can be employed. Examples of such means include (i) a means for axial rotation (first embodiment), (ii) a means for horizontal movement (second embodiment), and (iii) a means for opening doors like double doors (third embodiment) so that the leading ends of each of the rear bars 6 of the bogie 2 can move between inner and outer positions at the rear of the bogie 2. In all embodiments, it is preferable that each of the two rear bars 6 be attached to the rear ends of the two side bars 5, respectively. This allows the floor space occupied by the towing device to be minimized relative to the size of the bogie. These embodiments will be described in order below.

[0024] (First embodiment) Figure 6 shows an example in which two rear bars 6 are each attached to two side bars 5, respectively, so as to be rotatable around the axis in the direction of travel of the towing vehicle 1, where (a) shows that the tip of each of the two rear bars 6 is in an inner position, (b) shows details of the mechanism when achieving (a), (c) shows that the tip of each of the two rear bars 6 is in an outer position, and (d) shows details of the mechanism when achieving (c).

[0025] 6A and 6C, each of the two rear bars 6 can rotate about its axis, so that the leading end of each of the two rear bars 6 can move between an inner position and an outer position at the rear of the bogie. This axial rotation is achieved by a driving means such as a motor or rotary actuator, and if necessary, via gears, as shown in 6B and 6D. By rotating the towing vehicle 1 about its axis in the direction of travel, the leading end of each of the two rear bars 6 can be moved between the inner position and the outer position.

[0026] In the embodiment of Figure 6, (a) and (b) are shown as having the tips of each of the two rear bars 6 in an inner position, and (c) and (d), which are rotated 90 degrees relative to these, are shown as having the tips of each of the two rear bars 6 in an outer position.However, in the present invention, this is not limited to these, and even if the bar is rotated 90 degrees in the opposite direction as in Figure 7(a) or rotated to an oblique position as in Figure 7(b), if the bogie 2 can be removed rearward from the bogie surrounding bar 4 without interfering with the two rear bars 6, the tips of each of the two rear bars 6 are also considered to be in an outer position.

[0027] (Second embodiment) Figure 8 shows an example in which two rear bars 6 are attached to two side bars 5, respectively, so as to be horizontally movable in the width direction of the towing vehicle 1, where (a) shows that the tip of each of the two rear bars 6 is in an inner position, (b) shows that the tip of each of the two rear bars 6 is in an outer position, and (c) shows details of the mechanism for horizontally moving the rear bars 6.

[0028] 8A and 8B, the two rear bars 6 each move horizontally, allowing the tip of each of the two rear bars 6 to move between an inner position and an outer position at the rear of the carriage. This horizontal movement can be achieved, for example, by a rack-and-pinion mechanism as shown in 8C. In this case, when a pinion 8 (gear) connected to a driving means 7 such as a motor or rotary actuator rotates, a linear movement (horizontal movement) is performed on the horizontally placed rack 9 side, and the direction of horizontal movement can be controlled by the direction of rotation of the pinion 8, allowing the tip of each of the rear bars 6 to move between the inner position and the outer position.

[0029] (Third embodiment) Figure 9 shows an example in which two rear bars 6 are attached to two side bars respectively so as to be able to swing outwards like doors so that the tips of the two rear bars 6 can move between a closed position in which they face each other in the width direction of the towing vehicle 1 and an open position in which they face towards the rear of the towing vehicle 1, (a) and (b) respectively showing a schematic plan view and a schematic side view when the tips of the two rear bars 6 are in an inward position, and (c) and (d) respectively showing a schematic plan view and a schematic side view when the tips of the rear bars 6 are in an outward position.

[0030] 9(a), (b), (c), and (d), when each of the two rear bars 6 opens backward like a double door, the leading ends of the two rear bars 6 can be positioned on the outside at the rear of the bogie, and conversely, when they close like a double door, they can be positioned on the inside. This double door movement can be achieved by rotating the side bars around a vertical shaft attached to the rearmost part of the side bars using driving means such as a motor or rotary actuator, if necessary via a gear, as in the first embodiment.

[0031] While typical examples of the towing vehicle and towing device of the present invention have been described above, changes and modifications to the details of the technology and additions of conventional technology can be made as appropriate without departing from the scope of the claims of the present invention. Therefore, the inside and outside positions of the two rear bars of the towing device of the present invention are not limited to the above-described examples. When in the inside position, it is sufficient that the rear bars can surround and restrain the inside of the sides and corners of the bogie, and that the rear bars can push the bogie from behind when the towing vehicle is moving. When in the outside position, it is sufficient that the bogie can be moved in and out between the two side bars of the towing device. Furthermore, the mechanism for moving the two rear bars between the inside and outside positions is not limited to the above-described example, and may be configured to be operated manually or by other mechanisms.

[0032] The towing vehicle of the present invention can easily and safely tow any type of dolly without directly connecting the towing vehicle to the dolly, and the operation is extremely simple because the dolly can be enclosed, restrained, and released simply by moving the rear bar, which is part of the dolly enclosure bar. Therefore, the towing vehicle of the present invention is extremely useful in industries that handle the sorting and delivery of large quantities of goods.

[0033] 1 Traction vehicle 2 Bogie 3 Traction device 4 Bogie encircling bar 5 Side bar 6 Rear bar 7 Drive means 8 Pinion 9 Rack

Claims

1. A towing vehicle having a towing device disposed at the rear for towing a dolly, the towing vehicle being an unmanned guided vehicle not intended for an operator to ride on, the towing device having no running drive wheels, the towing device having a dolly encircling bar including two side bars capable of running along each side of the dolly, and two rear bars continuous therewith and capable of running along the inside from each corner of the rear of the dolly, the towing device being attached to each of the ends of the two side bars on the towing vehicle side, and the tip of each of the two rear bars being movable between an inside position and an outside position at the rear of the dolly. When the bogie is to be released without being towed, the tips of the two rear bars each move to an outer position at the rear of the bogie, thereby releasing the bogie out of the bogie encircling bar, and when the bogie is to be surrounded and towed, the tips of the two rear bars each move to an inner position at the rear of the bogie, thereby surrounding the bogie along the inside from the side and rear corners of the bogie, and as the towing vehicle moves forward with the bogie surrounded, the rear bars of the bogie encircling bar push the bogie from the rear in the direction of travel, thereby towing the bogie in the direction of travel.

2. A towing vehicle as described in claim 1, characterized in that each of the two rear bars is attached to the rear ends of the two side bars respectively so as to be rotatable about an axis in the direction of travel of the towing vehicle, and this rotation of the axis is configured so that the tip of each of the two rear bars can be moved between an inner position and an outer position at the rear of the bogie.

3. A towing vehicle as described in claim 1, characterized in that each of the two rear bars is attached to each of the two side bars so as to be horizontally movable in the width direction of the towing vehicle, and this horizontal movement enables the tip of each of the two rear bars to move between an inner position and an outer position at the rear of the bogie.

4. A towing vehicle as described in claim 1, characterized in that each of the two rear bars is attached to each of the two side bars in a manner that allows the distal ends of the two rear bars to open outwardly from each other in the width direction of the towing vehicle and move between a closed position in which the distal ends face each other in the width direction of the towing vehicle and an open position in which the distal ends face the rear of the towing vehicle, and this opening movement allows the distal ends of each of the two rear bars to move between a position on the inside of the rear of the bogie and a position on the outside.

5. A towing vehicle as claimed in claim 1, characterized in that each of the two side bars is configured to be movable in the width direction of the towing vehicle so that they can move away from or towards each other while remaining parallel to each other.

6. The towing vehicle according to claim 1, wherein the towing device is configured to be detachable from the towing vehicle.

7. The towing vehicle according to claim 1, characterized in that the bogie is a flatbed truck, a six-wheeled truck, or a cage truck.

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