Driverless transport system for transporting objects and method for operating a driverless transport system for transporting objects

Description

[0001] The present invention relates to a driverless transport system for transporting objects. The invention further relates to a method for operating a driverless transport system for transporting objects.

[0002] As industrial processes become increasingly digitized, the transport of goods is also becoming more and more automated. This is achieved using so-called driverless transport devices and automated guided vehicles (AGVs), which are also known as automated guided vehicles (AGVs). "Automated Guide Vehicles"(AGV). In automated guided vehicles (AGVs), a number of these vehicles are grouped together and operated like a swarm. AGVs are used particularly in logistics and manufacturing, where various items, such as semi-finished products or other components, need to be transported from one location to another. For example, trucks can be automatically loaded and unloaded.

[0003] In many cases, the items are transported using load carriers, such as crates, boxes, or pallets. German patent DE 10 2013 017 062 A1 discloses a driverless transport system which has two conveyor skids that can be inserted into the elongated cavities of a pallet, similar to the forks of a forklift. The conveyor skids have a lifting device that raises the pallet slightly from the ground, transports it to the desired location, and then lowers it again.

[0004] Due to the fact that the conveyor skids have a significantly greater longitudinal extent compared to the transverse extent, maneuverability is limited, particularly because sufficient space must be available in front of the pallet to align the conveyor skids with the cavities. The device shown in EP 2 765 101 A1 also has a similar extent to the aforementioned conveyor skids, resulting in limited maneuverability.

[0005] Another automated guided vehicle (AGV) system is described in DE 10 2013 101 561A1 and DE 20 2014 104 780 U1, which uses reference markers that define the path along which the AGV can move. This results in limited flexibility, as operation outside the reference markers is not possible. Furthermore, laying the reference markers requires considerable effort. Reference is also made to US 2018 / 039258 A1, DE 10 2015 110 555 A1, US 2019 / 310 656 A1, US 2015 / 125 252 A1, US 2017 / 308 084 A1, US 2015 / 182 083 A1, and EO 2 425 700 A2.

[0006] One embodiment of the invention is based on the objective of creating a driverless transport system and a method with which a plurality of driverless transport devices can be reliably operated while providing additional functions.

[0007] This problem is solved by the features specified in claims 1 and 13. Advantageous embodiments are the subject of the dependent claims.

[0008] One embodiment of the invention relates to a driverless transport system comprising comprising a plurality of driverless transport devices, ∘ a supporting structure with an outer contour, ∘ a chassis attached to the supporting structure with at least one first wheel and a second wheel, wherein the first wheel is rotatably mounted in the chassis about a first axis of rotation and the second wheel about a second axis of rotation, ∘ a drive unit with which the first wheel and the second wheel can be driven independently of each other, and ∘ at least one support section which cooperates with the objects for transporting them, a control unit for controlling or regulating the driverless transport devices, and a communication device with which information can be exchanged between the control unit and the driverless transport devices, wherein one of the driverless transport devices is designed as a master and the others of the driverless transport devices are designed as slaves.

[0009] The items that can be transported with the automated guided vehicle (AGV) system are primarily load carriers such as pallets, crates, or boxes on or in which goods and merchandise are placed. However, other items can also be transported with the AGV using appropriate adapters, for example, strollers, hospital beds, or garbage cans.

[0010] The automated guided vehicle (AGV) system comprises multiple AGVs, the number of which can be chosen arbitrarily. The minimum number should be two. Depending on the items to be transported, three or four AGVs will be most suitable. The system can also include several subgroups, for example, of four AGVs each, where the number of AGVs in each subgroup does not have to be the same.

[0011] To transport objects using multiple automated guided vehicles (AGVs), these vehicles must be coordinated, which is the function of the control unit. Furthermore, information must be exchanged between the control unit and the AGVs to facilitate this coordination; this is the function of the communication unit. The communication unit can utilize a Wi-Fi network or similar technology. Each AGV and the control unit has a transmitter / receiver unit for this purpose. This transmitter / receiver unit can also function as a relay station and operate as a repeater to maintain the stability of the Wi-Fi network. The Wi-Fi network may be insufficient, especially when some of the AGVs are located behind goods. The repeater function also amplifies the Wi-Fi network in areas with weak Wi-Fi coverage.

[0012] The control unit allows you to define the tasks that the automated guided vehicle (AGV) system is to perform. In particular, you can identify the items to be transported. Furthermore, you can define the current location and the destination location of the items to be transported.

[0013] Due to the fact that the first wheel and the second wheel can be driven independently of each other, the driverless transport device can be turned with a very small radius or even on the spot, which significantly increases the maneuverability of the driverless transport system and the transported object compared to known transport devices.

[0014] The master differs from the slaves in that it is not involved in transporting the objects. Rather, the master acts as a kind of guide, particularly for assessing the surroundings of the transported object. For example, if the slaves lift a pallet, the pallet severely restricts the area they can detect, while the master can move independently of the transported object and is therefore not limited by it. Furthermore, the master can explore areas with limited visibility, such as corners of factory buildings, and only issue a movement command to the slaves if the surroundings pose no hazards. This increases operational safety. Two or more masters can also be defined if necessary or desirable for operational safety.The distinction between master and slave can only be made by the software, so the master and the slave can be identical in construction.

[0015] According to another embodiment, the master has a master sensor unit for sensing its surroundings, and the master transmits information about its surroundings to the control unit and / or the slaves. The master differs from the slaves in that only the master has the master sensor unit. The slaves either have no sensor unit at all or only a significantly simpler one. The master sensor unit is designed to detect not only the immediate surroundings of the master itself, but also the surroundings of all slaves. Therefore, the master sensor unit must be correspondingly powerful. Because the slaves need not have a sensor unit, or only a significantly simpler one, the complexity of the sensor units used can be reduced.The more slaves are used, the greater the achievable benefit. The master can also be equipped with a particularly powerful communication device to ensure sufficient network coverage, for example, within the factory hall. The master can be positioned to amplify the network, such as the WLAN network, particularly effectively, thus guaranteeing information exchange with all slaves. The master can continuously adjust its position to the network strength and the location of the slaves.

[0016] A further developed version is characterized by the fact that Each of the transport devices has a sensor unit for detecting the environment of the transport device, wherein the sensor unit is arranged in a sensor section bounded by the outer contour and the first axis of rotation or the second axis of rotation, and the sensor unit is designed such that it detects only the part of the environment on the side of the first axis of rotation or the second axis of rotation on which the sensor unit is arranged, wherein at least one first of the sensor units is oriented in a first direction and at least one second of the sensor units is oriented in a second direction.

[0017] In this configuration, all automated guided vehicles (AGVs) combined into a transport system have the same sensor units. For example, if two AGVs are combined into a transport system, the sensor unit of the first AGV can face forward (in the direction of travel) and the sensor unit of the second AGV can face backward. This allows for sufficient monitoring of the AGV's surroundings without requiring particularly powerful sensor units.

[0018] In a further embodiment, one or more driverless transport devices are equipped with a force measuring device that can determine the force acting on the load-bearing section interacting with the object. This prevents overloading of the driverless transport device and the resulting damage. Furthermore, the weight of the transported object can be determined. This opens up various areas of application. As mentioned earlier, waste containers can also be transported using the driverless transport device. Since the weight of the respective waste container can be determined, usage-based billing of waste disposal fees is possible. As also mentioned, the driverless transport device can also be used to load trucks. Overloading of the truck can also be avoided.Furthermore, this allows for a more even loading of the truck's cargo area. This can, in particular, reduce the risk of the truck skidding during transport and contribute to road safety.

[0019] According to a further embodiment, the outer contour of the support structure is substantially rotationally symmetrical about an axis of rotation in plan view, with the support section and / or the first and second wheels arranged within or flush with the outer contour. The first and second axes of rotation typically run substantially parallel to a surface on which the first and second wheels roll. This surface is, for example, the loading platform of a truck or the floor of a factory building. In the intended use of the automated guided vehicle (AGV), particularly when it is rolling on the surface, the axis of rotation should run substantially perpendicular to the surface. The outer contour is understood to be the outer edge of the support structure, which can also be formed by a housing.

[0020] Due to the fact that the outer contour is rotationally symmetrical with respect to the axis of rotation and the support section and / or the first and second wheels are arranged within the outer contour, the automated guided vehicle (AGV) according to this embodiment has no eccentric sections. For example, if the AGV is located in the elongated cavities of a pallet and is to be rotated on the spot, it is ensured that a 360° rotation is possible without the AGV striking the pallet with eccentric sections.

[0021] In a further developed embodiment, the transport device can have a sensor unit for detecting the environment of the transport device, wherein the sensor unit is arranged in a sensor section bounded by the outer contour and the first axis of rotation or the second axis of rotation, and the sensor unit is designed such that it detects only the part of the environment on the side of the first axis of rotation or the second axis of rotation on which the sensor unit is arranged.

[0022] Known driverless transport systems incorporate sensor units that can detect their immediate surroundings. For example, obstacles can be identified and appropriate countermeasures initiated. Depending on the type of obstacle, it can be avoided or the driverless transport system can be stopped. Since driverless transport systems pose a significant risk to people in the vicinity, and to ensure smooth operation, the surroundings must be continuously monitored. Consequently, the sensor unit must be capable of capturing 360° of the environment. The necessary sensor technology for this is comparatively complex.

[0023] In this embodiment, the sensor unit is positioned to detect a maximum of 180° of the surroundings. Particularly due to the possibility of designing the outer contour to be rotationally symmetrical and the ability to rotate the automated guided vehicle (AGV) more or less on the spot, reversing is unnecessary. Therefore, it is sufficient to detect only 180° of the surroundings. The sensor unit is positioned to detect the area in front of the AGV in the direction of travel. Consequently, the sensor unit can be designed much more simply, and the corresponding AGV can be provided more cost-effectively.

[0024] By definition, the sensor section is the section of the automated guided vehicle (AGV) between the axis of rotation and the outer contour. If the AGV has multiple axes of rotation, the sensor section is the one that covers the smallest area perpendicular to the axis of rotation or in a top view.

[0025] In a further developed embodiment of the driverless transport system, the transport device can have a storage device for electrical energy which, in plan view, protrudes section by section beyond the outer contour of the supporting structure, wherein the storage device is movably attached to the supporting structure.

[0026] Again, the top view refers to the intended use, in which the first and second wheels roll on a surface. In this top view, one therefore looks along the aforementioned axis of rotation. Depending on the embodiment, the outer contour can be rotationally symmetrical to the axis of rotation, so that when the automated guided vehicle (AGV) rotates around the axis, no eccentric sections can, for example, strike the walls of the cavities of a pallet. The energy storage unit, which is required, for example, to drive the wheels and operate the sensor unit, protrudes section by section beyond the outer contour of the support structure, thus forming an eccentric section.

[0027] This allows the storage unit to expand its enclosed space and increase its load capacity. However, there is a risk that the storage unit might collide with adjacent objects, such as the aforementioned walls of the pallet cavities, when rotating. However, the storage unit is movably attached to the support structure, so that if it does collide with the walls of the pallet cavities, for example, it does not impede the further rotation of the automated guided vehicle (AGV). Consequently, in this embodiment, the storage unit's load capacity can be increased without restricting the maneuverability of the AGV.

[0028] In another embodiment, the storage unit can be rotatably attached to the support structure about the axis of rotation. Particularly when the outer contour of the support structure is rotationally symmetrical to the axis of rotation, it is advantageous to also attach the storage unit to the support structure so that it can be rotatably attached about the axis of rotation. For this purpose, an annular groove can be provided into which the storage unit engages with a correspondingly shaped projection in a form-fitting manner. This is especially beneficial when the automated guided vehicle (AGV) is to be rotated on the spot and the storage unit comes into contact with an adjacent object, as the rotation is not impeded.

[0029] A further developed embodiment is characterized in that the memory is arranged outside the sensor section. As already mentioned, the memory can be movably attached to the support structure. However, to prevent the memory from being positioned in a way that impairs the sensor's functionality, its movement can be restricted. This can be achieved, for example, by ensuring that the aforementioned annular groove does not protrude into the sensor section. In this way, the sensor's proper functioning is guaranteed despite the memory's movable attachment to the support structure.

[0030] According to a further embodiment, the storage unit is detachably attached to the support structure. This detachable attachment simplifies the charging process. In particular, an empty storage unit can be quickly replaced with a fully charged one. The empty unit can be charged while the fully charged unit ensures the operation of the automated guided vehicle (AGV). Replacing an empty unit with a full one can be automated, allowing for timely replacement with minimal operational disruption and without user intervention.

[0031] Another embodiment is characterized by the transport device having at least one support wheel and / or a bristle section. The number of wheels mounted in the chassis is generally freely selectable. For example, it is possible to provide three or four wheels to prevent the transport device from tipping over. However, the technical complexity is kept low and maneuverability is increased if only two wheels are provided. In this case, however, the driverless transport device can tip over, causing part of its supporting structure to rest on the surface and drag. To prevent this tipping, a support wheel and / or a bristle section can be provided. The support wheel should differ from the wheels in that it is not driven, but in particular, it is rotatable about an axis of rotation parallel to the axis of rotation and can therefore steer.It is understandable that several such support wheels may be provided.

[0032] The bristle section can be fitted with a number of appropriately durable bristles. Providing a bristle section also prevents tipping and scraping. Furthermore, the bristles act like a broom, removing at least minor obstacles such as dirt particles from the area in front of the transport device in the direction of travel. These obstacles therefore do not impede the wheels' rolling motion on the surface.

[0033] According to a further embodiment, all wheels can be rotatably arranged about a common axis of rotation, and the automated guided vehicle (AGV) can have a self-stabilizing device. In this embodiment, the AGV is rotatable about the common axis of rotation, so that it can tip over if the load is not perfectly even. As a result, the support structure can, as already mentioned, drag on the surface. In this embodiment, the AGV has a self-stabilizing device, which can include, for example, a tilt sensor or a gyroscope. If it is detected that the AGV is rotating about the common axis of rotation and there is a risk that the support structure will come into contact with the surface, stabilizing countermeasures can be taken to reduce the tilt of the AGV to a non-critical level.This can be achieved, for example, by controlling the drive unit so that the wheels are rotated in such a way as to generate a torque that counteracts tilting. It is also possible to incorporate counterweights or balance shafts that can be shifted within the supporting structure depending on the inclination, thereby also generating a torque that counteracts tilting.

[0034] In a further developed embodiment, the transport device can have a signal transmitter for emitting a warning signal. The warning signal can be emitted, in particular, in visual and / or acoustic form. The warning signal can be emitted in various situations, for example, if the automated guided vehicle (AGV) is defective, if an unexpected obstacle is detected that cannot be overcome, or if it is determined that the object to be transported is too heavy and the AGV would consequently be overloaded.

[0035] In a further developed embodiment, the transport device can have a carrying handle for gripping it. Depending on the design of the transport device, it can weigh less than 10 kg, allowing it to be carried by one user. This enables the transport device to be moved flexibly from one place to another without having to travel the distance itself. The carrying handle makes carrying easier.

[0036] According to a further embodiment, the automated guided vehicle (AGV) comprises a lifting device that interacts with the supporting structure for raising and lowering at least one support section, which, in conjunction with the objects themselves, facilitates their transport. It is generally possible to place the object to be transported onto the AGV using, for example, a crane or forklift, and then move it to the desired destination. In this case, however, it is necessary to lift the object to remove it from the ground. The AGV can also be used to move objects that have their own wheels, such as hospital beds or garbage cans. These objects do not necessarily need to be lifted to be moved.

[0037] Using the lifting mechanism, the automated guided vehicle (AGV) can be moved into a corresponding recess in the item being transported, for example, the aforementioned elongated cavity of the pallet, while the pallet is still on the ground. Once the AGV is in the desired position, the lifting mechanism is activated, raising the pallet from the ground. The spreading mechanism is then activated, allowing the AGV to align itself with the pallet. Furthermore, the AGV is frictionally engaged with the pallet, largely preventing the pallet from slipping relative to the AGV. This can be particularly important when the pallet is to be transported along an inclined surface.It is therefore also possible to transport objects without having to lift them and place them on the automated guided vehicle (AGV) beforehand. Furthermore, it is also possible to transport objects that do not have wheels or similar components and therefore cannot be pulled.

[0038] One embodiment of the invention relates to a method for operating a driverless transport device according to one of the previously presented embodiments, comprising the following steps: Designating one of the driverless transport devices (10) as the master and the other driverless transport devices as slaves, positioning the master such that ∘ the environment of the master can be detected by means of the master sensor unit, and ∘ transmitting information relating to the environment of the master to the control unit and / or to the slaves by means of the communication device, and / or ∘ the wireless network is available for all slaves.

[0039] The master differs from the slaves in that it is not involved in transporting the objects. Rather, the master acts as a kind of guide, particularly for assessing the surroundings of the transported object. For example, if the slaves lift a pallet, the pallet severely restricts the area they can detect, while the master can move independently of the transported object and is therefore not limited by it. Furthermore, the master can explore areas with limited visibility, such as corners of factory buildings, and only issue a movement command to the slaves if the surroundings pose no hazards. This increases operational safety. Two or more masters can also be defined if necessary or desirable for operational safety.

[0040] Furthermore, a properly functioning wireless network, such as a WLAN network, is essential for operating the transport system. However, it can happen that the network is blocked by objects like machinery or similar equipment located, for example, in a factory hall, preventing some of the slaves from receiving a signal. In this implementation of the system, the master can be positioned so that the network is receivable for every slave. For this purpose, the master can be operated like a repeater or relay station.

[0041] For further training, the process includes the following steps: Detection of the environment of the transport device by means of a sensor unit with regard to selectable properties, and raising or lowering of the carrying section by means of the lifting device depending on the detected properties of the environment.

[0042] One of the selectable properties is the flatness of the surface on which the transport device rolls. If the sensor unit detects unevenness, such as bumps in the ground, which could cause the transported items to slip or fall off the device, the support section can be raised or lowered accordingly. This minimizes shocks and vibrations affecting the transported items, thus protecting them.

[0043] For further training, the process includes the following steps: Defining a loading area that is to be loaded with a plurality of objects using the driverless transport device, transporting a first object onto the loading area, determining the first force acting on the support section using the force measuring device, placing the first object at a first position on the loading area, transporting a second object onto the loading area, determining the second force acting on the support section using the force measuring device, and placing the second object at a second position on the loading area, wherein the second position is selected depending on the first force and the second force such that the loading area is loaded evenly.

[0044] As mentioned, the transport device can be designed to determine the weight of the transported item(s). When loading a cargo area, such as the bed of a truck, the transport device can be operated to ensure the cargo area is loaded as evenly as possible. This is achieved by selecting the positions where items are placed on the cargo area based on their weight. Even loading contributes to the road safety of the truck and, in particular, reduces the risk of skidding. This principle also applies to loading other means of transport, such as ships and aircraft.

[0045] A more advanced training in the procedure prescribes the following step: Changing the first position and / or the second position to even out the loading of the cargo area.

[0046] Since the weight of the items to be placed on the loading platform is not necessarily known in advance, it may be possible to adjust the initially selected positions to even out the load. The procedure according to this design can, for example, be carried out by first loading the platform until all items to be transported by the truck are placed on it. The automated guided vehicle (AGV) then records the position and weight of the items placed on the loading platform. After loading is complete, the AGV then adjusts the positions of the corresponding items within the loading platform to ensure the most even load possible, if necessary.

[0047] According to advanced training, the procedure comprises the following steps: Defining a maximum load for the loading area, and issuing a warning signal via the signal transmitter when the defined maximum load is reached or exceeded.

[0048] In this version of the procedure, the transport device emits a warning signal when the maximum load is reached or exceeded. Alternatively or additionally, the transport device can suspend further loading of the loading platform. This prevents overloading of the loading platform.

[0049] One implementation of the present invention relates to a method for operating a driverless transport system according to one of the previous embodiments, comprising the following steps: Determining the force acting on the respective support sections of the transport device using the force measuring devices, transmitting the determined forces to the control unit using the communication device, comparing the determined forces using the control unit, and raising or lowering one or more of the support sections using the lifting devices depending on the comparison at the instigation of the control unit.

[0050] This implementation of the invention is used when an object is lifted and transported by several transport devices. If it is observed that the force acting on a support section of a first transport device differs significantly from the force acting on the support section of a second or third transport device, this can be interpreted as an indication that the weight of the object is unevenly distributed among the transport devices involved. The support section of the first transport device is lowered until the force acting on this support section is approximately equal to that acting on the other support sections. This evens out the load on the transport devices and prevents excessive stress on any single device. The wear and tear on the transport devices used also becomes more uniform.

[0051] One variant of the present invention relates to a method for operating a driverless transport system according to one of the preceding embodiments, comprising the following steps: Transporting an object with at least two transport devices, detecting the environment of at least one transport device by means of a sensor unit with regard to selectable properties, and raising or lowering the support sections by means of the lifting devices depending on the detected properties of the environment.

[0052] As mentioned previously, one of the selectable properties can be the flatness of the surface on which the transport devices roll. If unevenness, such as bumps in the floor, is detected that could cause the transported object to come to rest on the surface between the two transport devices, the support sections are raised to prevent this. This prevents disruptions in the operational process.

[0053] Exemplary embodiments of the invention are explained in more detail below with reference to the accompanying drawings. These show Figure 1A a perspective view of a first embodiment of a transport device according to the invention for transporting objects, Figure 1Legs a general and not to scale top view of the in Figure 1AFigure 1 shows an embodiment of the transport device, Figure 2 a perspective view of a second embodiment of the transport device according to the invention, Figure 3A an isolated and perspective exploded view of a lifting device of the transport device, Figure 3B an isolated view of a force measuring device according to a first embodiment, which is integrated into the lifting device, Figure 3C an isolated view of a force measuring device according to a second embodiment, which is integrated into the lifting device, Figure 4 a schematic view of a part of a support structure of the transport device according to a third embodiment, to which an electrical energy storage device is movably attached, Figure 5 a top view of an object which is transported by a transport system,Figure 6A a side view of a third embodiment of the transport device according to the invention, which has a spreading device, Figure 6Legs top view of the in , Figure 6A Figure 6C shows the third embodiment of the transport device according to the invention; Figure 6C shows a sectional view through the third embodiment of the transport device along the section plane AA defined in Figure 6B; Figure 6B shows a sectional view through the third embodiment of the transport device along the section plane BB defined in Figure 6B; Figure 6E shows an enlarged view of the transport device shown in Figure 6B. Figure 6Dcharacterized section Q, Figure 6Fine isolated view of an actuating element of a decoupling unit, Figure 7Aa perspective view of a fourth embodiment of the transport device according to the invention, which has a spreading device, Figure 7Bthe spreading device of the transport device according to the fourth embodiment in an isolated top view, wherein the spreading device is in a first position, Figure 7Cthe in Figure 7B Figure 8 shows a spreading device in a second position based on a bottom view, Figure 8 a loading area which is loaded with a plurality of objects using a transport system, and Figure 9 a factory hall in which a transport system is used.

[0054] In the Figures 1A and 1B A first embodiment of a transport device 10 1 according to the present invention is shown. Figure 1AThe transport device 10 1 is shown using a perspective view, while in the Figure 1B a top view of the in the Figure 1A The transport device 10 1 shown is reproduced, wherein the Figure 1B not to scale and only of a general nature.

[0055] The transport device 10 1 has a support structure 12, which in the present embodiment is formed by a housing 13 having an outer contour 14. The outer contour 14 denotes the outer surfaces and edges of the support structure 12 or the housing 13. A chassis 16 is attached to the support structure 12, in which a first wheel 18 and a second wheel 20 are rotatably mounted about a first axis of rotation D1 and a second axis of rotation D2. In the illustrated embodiment, the first axis of rotation D1 and the second axis of rotation D2 coincide, so that a common axis of rotation D exists.

[0056] The transport device 10 1 further comprises a drive unit 22, which is also attached to the support structure 12. In this case, the drive unit 22 has a first drive motor 24 and a second drive motor 26, with the first drive motor 24 being located adjacent to the first wheel 18 and the second drive motor 26 adjacent to the second wheel 20. The first drive motor 24 is connected to the first wheel 18 via a first gearbox 28, and the second drive motor 26 is connected to the second wheel 20 via a second gearbox 30, so that the rotary motion provided by the first drive motor 24 and the second drive motor 26 can be transmitted directly to the first wheel 18 and the second wheel 20, respectively.The first drive motor 24 can be operated independently of the second drive motor 26, so that the first wheel 18 and the second wheel 20 can also be driven in different directions and at different speeds, which allows the transport device 10 1 to be rotated.

[0057] Furthermore, the transport device 10 1 includes a lifting device 32, which is located in Figure 3AThe lifting device 32 is shown separately. The lifting device 32 is equipped with a spindle nut 34, which can be rotated about a rotational axis R by means of a third drive motor 36. The rotational axis R runs perpendicular to the common axis of rotation D and is vertical in normal use. The spindle nut 34 interacts with a non-rotating spindle 37, which in turn is connected to a support section 39. In the first embodiment of the transport device 101, this support section is designed as a turntable that is rotatable relative to the housing 13. When the spindle nut 34 is rotated about the rotational axis R by means of the third drive motor 36, the spindle 37 and the support section 39 connected to it are moved along the rotational axis R. With regard to the normal use of the transport device 101, which occurs when the first wheel 18 and the second wheel 20 are on a surface in the Figures 1A and 1BAs the load rolls off the support surface (not shown), the support section 39 is either raised or lowered depending on the direction of rotation of the third drive motor 36. To transport an object 38, for example a pallet 40 (see Figure 5 The transport device 101 is moved into a cavity in the pallet 40, and then the lifting device 32 is activated such that the support section 39 is raised. The support section 39 is thus brought into contact with the pallet 40, which is consequently lifted so that it no longer makes contact with the base. The pallet 40 can then be moved to the desired location using the transport device 101.

[0058] Referring to the Figure 3AIt can be seen that the support section 39 of the lifting device 32 has a plate 42 and a studded mat 44 connected to the plate 42. The studded mat 44 can, for example, be glued to the plate 42. The plate 42 is connected to the spindle 37 by means of a clamping sleeve 46. The clamping sleeve 46 also simultaneously fastens a plate housing 48, open towards the plate 42, to the spindle 37. An O-ring 50 is inserted into a circumferential groove of the clamping sleeve 46 and seals the clamping sleeve 46 against the plate 42. An axial roller bearing 52 is arranged in the plate housing 48, so that the support section 39 can rotate relative to the plate housing 48 and the rest of the transport device 10 1. A rubber ring 54 is arranged between the axial roller bearing 52 and the plate 42. The rubber ring 54 allows tilting movements between the plate 42 and the axial roller bearing 52, which are caused by an uneven load on the support section 39.

[0059] Furthermore, a force measuring device 56 1 is arranged in the plate housing 48 according to a first embodiment, which is located in the Figure 3BThe force measuring device 56 1, in the first embodiment, comprises a total of six capacitive force sensors 58, which can be divided into a first group 60 and a second group 62, each containing three force sensors 58. The main surfaces of the force sensors 58 of the first group 60 lie in a horizontal plane with respect to the intended use of the transport device 10 1, while the main surfaces of the force sensors 58 of the second group 62 are oriented perpendicular to the main surfaces of the force sensors 58 of the first group 60. The force sensors 58 of the first group 60 are annular sector-shaped, while the force sensors of the second group 62 are cylindrical sector-shaped. The main surfaces of the force sensors 58 of the second group 62 lie in a vertical plane during the intended use of the transport device 10 1.Instead of the capacitive force sensors 58, resistive force sensors, strain gauges or printed electronics can also be used.

[0060] In Figure 3C A second embodiment of the force measuring device 56 2 is shown, which differs from the force measuring device 56 1 according to the first embodiment essentially in that it has only three capacitive force sensors 58, which can be assigned to the first group 60.

[0061] In both cases, it is possible to measure horizontally acting and vertically acting forces. Furthermore, depending on how the force sensors 58 are mechanically mounted, tilting, rotating, and sliding movements can be measured.

[0062] In the first embodiment of the force measuring device 56 1, the force sensors 58 of the first group 60 are used to determine vertically acting forces. The force sensors 58 of the second group 62 are used to determine horizontally acting forces. Due to the division of the force sensors 58 into the first group 60 and the second group 62, the different load cases can be distinguished from one another more precisely than is the case in the second embodiment of the force measuring device 56 2. Since, in principle, the different load cases can be described better with an increasing number of force sensors 58, efforts are being made to increase the number of force sensors 58. However, this increases the space requirement.The arrangement of the force sensors 58 of the first group 60 perpendicular to the force sensors 58 of the second group 62 increases, on the one hand, the accuracy with which the load cases can be described, and on the other hand, keeps the installation space required for this within reasonable limits.

[0063] The force sensors 58 interact with an evaluation unit 63 to determine the forces acting on the support section 39. The evaluation unit 63 also allows the distribution of these forces across the support section 39 to be determined. Due to the degrees of freedom provided by the mounting of the support section 39 in the lifting device 32, specific load cases, such as tipping, can be defined and analyzed. Furthermore, the loads that can be determined depend on the arrangement of the force sensors 58 relative to the support section 39.

[0064] The information on the magnitude and distribution of the forces acting on the support section 39 can be used in various ways, which will be discussed in more detail later. At this point, it should only be noted that overloading of the transport device 10 1 can be prevented. If the force acting on the support section 39 exceeds a certain value, the lifting of the support section 39 can be interrupted and stopped by means of a signal transmitter 64 (see Figure 1B ) a corresponding warning signal will be issued. The warning signal can be issued, for example, in visual and / or audible form.

[0065] Referring to the Figures 1A and 1BThe transport device 101 has a sensor unit 66 with which the environment of the transport device 101 can be detected. In particular, obstacles and the condition of the surface on which the wheels roll can be determined. The sensor unit 66 can comprise cameras 67, ultrasonic sensors 69, laser-based sensors 71, radar-based sensors, or the like, with which the environment can be detected with sufficient accuracy even under different conditions. The sensor unit 66 is arranged in a sensor section 68, which is bounded by the outer contour 14 and by the common axis of rotation D or by a plane passing through the common axis of rotation D and the axis of rotation R. According to this definition, the transport device 101 has two such sensor sections 68, but the sensor unit 66 is arranged in only one of these sensor sections 68.This arrangement means that the sensor unit 66 can only detect the part of the environment which is located on the side of the common axis of rotation D or the plane passing through it, on which the sensor unit 66 is located.

[0066] In addition, the transport device 10 1 is equipped with a storage unit 70 for electrical energy so that the relevant components can be supplied with electrical energy.

[0067] As can be seen in particular from the Figure 1BAs can be seen, the outer contour 14 is at least partially rotationally symmetrical about the axis of rotation R. Furthermore, the support section 39 and the first wheel 18 and the second wheel 20 are arranged within the outer contour 14. Therefore, no components project radially beyond the outer contour 14. This results in the effect that when the transport device 10 is rotated on the spot, which can be achieved by appropriately controlling the first wheel 18 and the second wheel 20, there are no eccentric sections that could collide with adjacent objects and impede the rotation, as long as the adjacent objects are at a distance that is at least equal to the radius of the outer contour 14 around the axis of rotation R.

[0068] Out of Figure 1AIt can be seen that a bristle section 72 is arranged at the lower edge of the housing 13, which consists of a multitude of bristles not explicitly visible here. As mentioned, the first wheel 18 and the second wheel 20 are arranged on a common axis of rotation D. Consequently, the transport device 10 1 can tilt about the common axis of rotation D, so that the housing 13 rests on the surface on one side of the common axis of rotation D and then, when the transport device 10 1 is moved, drags along the surface. This dragging is prevented by the bristle section 72, which also has a stabilizing effect on the transport device 10 1. Furthermore, the bristle section 72 has the effect of a broom, so that at least smaller particles are removed and cannot negatively affect the rolling of the wheels 18, 20 on the surface.

[0069] To stabilize the transport device 10 1 around the common axis of rotation D, one or more support wheels (not shown) can alternatively be used.

[0070] In the illustrated embodiment, the transport device 10 1 is further equipped with a self-stabilizing device 74 ( Figure 1B), which can detect and counteract the inclination and change in inclination of the transport device 10 1 about the common axis of rotation D. For example, the self-stabilizing device 74 can include a gyroscope or an inclination sensor. If the self-stabilizing device 74 detects that the inclination about the common axis of rotation D exceeds a critical value, it can initiate countermeasures. These countermeasures can consist, for example, of selectively accelerating or decelerating the first wheel 18 and / or the second wheel 20. Alternatively, a counterbalance shaft (not shown) can be driven, or weights (also not shown) can be displaced. All measures serve to generate a torque around the axis of rotation D within the transport device 10 1 that counteracts the inclination, in order to reduce the inclination back to values ​​below the critical value.It should be noted that the self-stabilizing device 74 can only be used if no objects are being transported with the transport device 10 1.

[0071] Furthermore, the transport device 10 1 is equipped with a communication device 76, with which the transport device 10 1 can exchange information with other communication partners, which will be discussed in more detail later.

[0072] In Figure 2Figure 1 shows a perspective view of a second embodiment of the transport device 10 2 according to the invention. The transport device 10 2 according to the second embodiment is largely constructed in the same way as the transport device 10 1 according to the first embodiment. In addition, the transport device 10 2 has a carrying handle 78, which is rotatably attached to the support structure 12. The transport device 10 1 can therefore be grasped and transported by the carrying handle 78, similar to a bucket.

[0073] In Figure 4A third embodiment of a support structure 12 of the transport device 10 3 according to the invention is shown in a schematic and perspective view, wherein the support structure 12 is designed as a housing 13. Two annular sector-shaped grooves 80 are arranged on one of the two curved outer surfaces AW of the housing 13, into which an electrical energy storage device 70 can engage in a form-fitting manner and be detachably connected to the housing 13. In this embodiment, the storage device 70 is therefore arranged outside the housing 13 in the manner of a backpack and forms an eccentric section. The storage device 70 can be moved within the two grooves 80, rotating about the axis of rotation R. The transport device 10 1 can therefore be moved on the spot within certain limits in spaces that are only slightly wider than the housing 13 at its two flat outer surfaces AP.Such spaces can be the cavities of pallets 40. During rotation, the storage unit 70 abuts the walls of the pallet 40 and, due to the rotational movement of the transport device 10 1, is rotated along the grooves 80 about the axis of rotation R of the transport device 10 1. The storage unit 70 does not impede the further rotation of the transport device 10 1.

[0074] In the Figure 5 A top view of an object 38 is shown, which can be transported by a transport system 81 according to the present invention. In the Figure 5 The object 38 is designed as a pallet 40, on which items such as boxes or the like, not shown in detail, may be placed. The pallet 40 shown has three crossbeams 82, onto which a total of five boards 84 are nailed. In each crossbeam 82 are two Figure 5Inconspicuous recesses are arranged, each aligned with the recesses of the adjacent crossbeams 82.

[0075] The transport system 81 comprises a total of seven transport devices 10, which are located in the Figures 1A and 1B are described and in the Figure 5 These are only shown in principle. Six of the transport devices 10 are each moved into one of the recesses in the crossbeams 82. The lifting device 32 is then raised so that the pallet 40 can be removed from the base and subsequently transported to the desired location. As shown in the Figure 5It is also apparent that a seventh transport device 10 1 is not inserted into the recesses of the pallet 40. The seventh transport device 10 1 is configured as a so-called master 86, while the other six transport devices 10 are designed as slaves 88. The master 86 serves in particular to detect the surroundings, since it is positioned outside the pallet 40 and can therefore detect the surroundings better than the slaves 88. Using the communication device 76, the master 86 can transmit commands to the slaves 88, especially regarding obstacles.

[0076] The master 86 accompanies the slaves 88 until the pallet 40 has been transported to the desired location. The lifting device 32 is then activated, so that the pallet 40 is placed back on the base. The slaves 88 then move out of the pallet 40 and can be used to transport another item. The seven transport devices 10 can be identical in construction. However, it is also possible to equip the master 86 with a particularly powerful master sensor unit 90 so that the surrounding area can be monitored over a larger area.

[0077] If the transport devices 10 are identical in design, each of them can be defined as either a master 86 or a slave 88. This distinction is determined solely by the software. The transport devices 10 can therefore be used in different ways. As mentioned, the master 86 serves to detect the environment of the pallet 40 as comprehensively as possible. For this purpose, the sensor unit 66 requires an above-average amount of electrical energy. Because one of the other transport devices 10 can also be used as a master 86, the memory 70 of one transport device 10 is prevented from being emptied faster than those of the other transport devices 10. Furthermore, all transport devices 10 are loaded evenly, thus preventing one or more of them from wearing out faster and requiring maintenance sooner than others.To transport the further item 38, another of the transport devices 10 can be used as Master 86.

[0078] In the Figure 6A A fourth embodiment of the proposed transport device 10 4 is shown in a side view and in Figure 6B shown using a top view. Figures 6C to 6E The sectional views show the fourth embodiment of the proposed transport device 10 4. The basic structure of the transport device 10 4 according to the fourth embodiment largely corresponds to that of the previously described embodiments, so that only the differences will be discussed below.

[0079] The transport device 10 4 according to the fourth embodiment comprises a spreading device 98, which in the fourth embodiment of the transport device 10 4 comprises two spreading arms 100 that are adjustable between a first position and a second position by means of an adjusting unit 106. Figure 6BThe two spreading arms 100 are shown in a second position, in which they project beyond the outer contour 14 of the support structure 12. In the first position (not shown), the spreading arms 100 are located within the outer contour 14, so that there are no eccentric sections that could collide with adjacent objects 38 when the transport device 104 rotates on the spot and thus impede rotation. The spreading arms 100 are slidably mounted in guide tracks 102, which are formed by grooves arranged in the support section 39. The guide tracks 102 extend radially outwards from the center of the transport device 104, allowing the spreading arms 100 to move in a radial direction.

[0080] To move the spreading arms 100 between the first and second positions, the spreading device 98 comprises, in addition to the adjusting unit 106, a further drive unit 107, which is described below in particular with reference to the Figures 6C to 6E The adjusting unit 106 and the further drive unit 107 interact using a drive train 109. The drive train 109 runs eccentrically to the axis of rotation R and comprises a first gear 111 and a second gear 113, which are in meshing engagement with each other, which is particularly evident from Figure 6A The first gear 111 is non-rotatably connected to the support section 39. This allows the rotary motion of the further drive unit 107 to be transmitted to the adjusting unit 106. The rotary motion allows the spreading arms 100 to be moved between the first and second positions. The mechanisms used for this will be discussed in more detail later.

[0081] As mentioned previously, the spindle 37 is mounted in the support structure 12 to prevent rotation. A corresponding bearing unit 119 is provided to allow the support section 39, and consequently the spreading device 98, to move relative to the housing 13. An angle sensor 121 is provided to determine the rotational position of the spreading device 98, for example, with respect to the first axis of rotation D1 and / or the second axis of rotation D2.

[0082] A decoupling unit 115 is arranged in the drive train 109, which allows the drive train 109 to be selectively opened and closed. The decoupling unit 115 serves the following purpose: The spreading arms 100 serve to connect the transport device 104 in the second position to the object 38 to be transported, in particular to a pallet 40 (see figure). Figure 5), to clamp it in order to prevent uncontrolled slippage. However, rotating the transport device 10 4 in the clamped state, especially for steering, would not be easily possible, as this would require overcoming the resistances present in the drive train 109 and in the further drive unit 107.

[0083] The decoupling unit 115 comprises a cam disk 117, which is in Figure 6F shown separately. The cam disk 117 is rotationally fixed but axially displaceable with an output shaft 124 of the further drive unit 107. The cam disk 117 has a groove 120 in its cylindrical surface with a helical profile and a specific pitch. A pin 122 anchored in the support structure 12 projects into the groove 120 ( Figure 6EWhen the cam disk 117 is rotated by the output shaft 124, it performs not only a rotational movement but also a translational movement parallel to the axis of rotation R. The translational movement of the cam disk 117 is transmitted to a coupling element 126, which is ring-shaped. The coupling element 126 makes contact with the cam disk 117 via a first end face 128. On a second end face 130, the coupling element 126 has a first spur gear 132, which, depending on its position, can engage with a corresponding second spur gear 134 of the second gear 113. Figure 6EIn the illustrated operating state, the first spur gear 132 and the second spur gear 134 are not engaged. When the first spur gear 132 and the second spur gear 134 are engaged, the rotary motion of the output shaft 124 of the further drive unit 107 is transmitted to the first gear 111, thereby moving the spreading arms 100. Depending on the direction of rotation of the output shaft 124, the coupling element 126 is moved from the cam disk 117 towards or away from the second gear 113. Accordingly, the first spur gear 132 and the second spur gear 134 can be brought into or out of engagement. To ensure contact between the cam disk 117 and the coupling element 126, the coupling element 126 interacts with a return spring 136.

[0084] For example, if the spreading arms 100 are moved from the second position to the first position, and the further drive unit 107 is rotated further in this direction after reaching the first position, this causes a rotation of the support section 39. In this way, the spreading device 98 and consequently the spreading arms 100 can be brought into any rotational position relative to the support structure 12 or the housing 13. The rotational position can be determined with the angle sensor 121. The same applies when the spreading arms have reached the second position.

[0085] In the Figures 7AA fifth embodiment of the transport device 10 5 according to the invention is shown in a perspective view. The construction of the transport device 10 5 according to the fifth embodiment is largely the same as that of the fourth embodiment of the transport device 10 4, in particular with regard to the construction of the drive train 109 and the adjustment unit 106.

[0086] The spreading device 98 comprises a total of six spreading arms 100, which are located in the Figure 7B in the first position and in the Figure 7C is in a second position. Also in the Figure 7AThe spreading arms 100 are in the first position. It can be seen that the spreading arms 100 do not protrude beyond the outer contour 14 of the support structure 12 when the spreading arms 100 are in the first position. As in the fourth embodiment of the transport device 10 4, the spreading arms 100 are slidably mounted in the guide tracks 102, the guide tracks 102 extending from grooves arranged in the support section 39, so that the support section 39 forms a corresponding number of circular sector elements 104 (see Figure 7A For presentation purposes, the circular sector elements 104 are shown in Figure 7C not shown.

[0087] The guide rails 102 extend radially outwards from the center of the transport device 104, so that the spreading arms 100 can also move in a radial direction, as can also be seen from a comparison of the Figures 7B and Figure 7CThe adjusting unit 106 comprises a toggle lever unit 108 for each spreading arm 100. These units can be extended or compressed by rotating a synchronizing unit 110, which in the illustrated embodiment includes a cam disk 112. Extending the toggle lever unit 108 moves the spreading arms 100 radially outward into the second position, and compressing the toggle lever unit 108 moves them into the first position. Since the cam disk 112 interacts with all toggle lever units 108 in the same way, all spreading arms 100 are moved simultaneously when the cam disk 112 is rotated.

[0088] The spreading device 98 includes a locking device 138, which allows the adjusting unit 106 to be locked at least when the spreading arms 100 are in the second position. In the fifth embodiment of the transport device, the locking device 138 is implemented as follows: The cam disk 112 interacts with the toggle lever units 108 in such a way that the two legs of the toggle lever units 108 are moved beyond an angle of 180° in the second position and are consequently forced over, resting against a stop 140 in the second position. This locks the spreading arms 100 in the second position without requiring a locking force. This makes it possible to hold the spreading arms 100 in the second position even when the drive train 109 is open.Therefore, the locking device 138 is largely formed by the adjusting unit 106 itself, so that no additional elements need to be provided for this purpose. Alternatively, however, the locking device 138 can comprise one or more movable bolts or the like with which the adjusting unit 138 can be locked.

[0089] Furthermore, a stop element 114 is connected to each radially outer end of the spreading arms 100. As can be seen in particular from the Figures 7A and 7B As can be seen, in the first position the stop elements 114 strike against the two adjacent stop elements 114. In addition, the stop elements 114 also strike against the circular sector elements 104. This clearly defines the first position of the spreading arms 100.

[0090] Each of the stop elements 114 has a support element 116 movably attached, the support elements 116 being pre-tensioned by means of a spring 118.

[0091] As particularly in Figure 5 As shown, a pallet 40 can be transported, for example, with a total of six transport devices 10. If transport devices 104, 105 are used according to the fourth or fifth embodiment, they are moved into a cavity of the pallet 40 until they are in the area of ​​the aforementioned crossbeam 82. The spreading device 98 is in the first position in this case.

[0092] Once the transport device 104, 105 has reached the desired position within the cavity, the lifting device is activated, raising the pallet 40. The spreading device 98 is then activated, moving the spreading arms 100 from the first position to the second position. This brings the support elements 116 into contact with the side walls of the pallet 40's cavity, thus frictionally connecting the transport device 104, 105 to the pallet 40. This compresses the springs 118, preventing impact loads. Furthermore, the support elements 116 can be floating, allowing manufacturing inaccuracies to be compensated for by the springs 118. As a result, the transport device 104, 105 is precisely aligned with the pallet 40. Consequently, pallet 40 can no longer move relative to the transport device 10 4 , 10 5.Now the pallet 40 can be moved to the desired destination using the transport device 10 5.

[0093] As mentioned, the transport device 10 5 according to the fifth embodiment differs from the transport device 10 4 according to the fourth embodiment, particularly in the number of spreading arms 100. Due to the higher number of spreading arms 100, the angle sensor 121 can be dispensed with, since the spreading device 98 can align itself so that the spreading arms 100 run largely parallel to the surface of the object 38 with which the transport device 10 4 is to be clamped.

[0094] In the Figure 8A transport system 81 is shown, comprising a total of six transport devices 10, which are distributed within a factory hall 92. Various items are stored in the factory hall 92 and are to be transported by the transport system 81. The transport system 81 includes a control unit 94 with which the transport devices 10 can be controlled or regulated. As already mentioned, the transport devices 10 are equipped with communication devices 76 (see Figure 1B), which enable the exchange of information between them. The control unit 94 is also equipped with such a communication device 76, so that the transport devices 10 can not only exchange information among themselves, but also between the transport devices 10 and the control unit 94. The control unit 94 can, for example, define tasks for the transport devices 10 to perform, which could, for example, consist of transporting the various items 38 from one location to the destination location. As mentioned, the transport devices 10 are located within a factory hall 92. The control unit 94 can be located outside the factory hall 92, but it can also be located inside the factory hall 92. The communication device 76 uses a wireless network, such as WLAN or Bluetooth, for information exchange.Depending on the design and size of the objects, it is not always guaranteed that the Wi-Fi will be sufficiently available throughout the entire Hall 92. However, the functionality of the transport system depends on a sufficiently available Wi-Fi network. To stabilize the Wi-Fi network, some or all of the transport devices 10 can be operated as repeaters or relay stations, ensuring that the Wi-Fi is also available in the corners of Hall 92 or behind or under the objects. As in connection with the... Figure 5 As described, one or more of the transport devices 10 can be operated as a master 86. As also mentioned, the master 86 primarily serves to detect the environment around the object 38 to be transported; however, the master 86 can also be positioned so that the WLAN network is available at least to the slaves 88 assigned to it.

[0095] In the Figure 9 A loading platform 96, for example that of a truck, is shown, which is loaded with the transport system 81 according to the invention. Due to the fact that the force acting on the support section 39 of at least one transport device 10 according to one of the previously described embodiments can be determined by means of the force measuring device 56, this information can also be used to load the loading platform 96 of the truck as evenly as possible. In the Figure 9In the example shown, the loading platform 96 is to be loaded with a total of six pallets 40, all of which are supposed to have the same weight. However, the transport system 81 cannot initially assume this. First, the transport system 81 places three pallets 40 side by side in a first row and records the exact position and weight of each pallet 40 on the loading platform 96. The transport device 10 1 then moves a fourth pallet 40 into a second row, and finally a fifth and sixth pallet 40 into a third row. After the sixth and final pallet 40 has been moved onto the loading platform 96, the transport system 81 receives the information that no further pallets 40 should be loaded onto the loading platform 96. The transport system 81 determines that the loading platform 96 is unevenly loaded.The transport system 81 changes the position of the fourth loading platform 96 so that the loading platform 96 is now evenly loaded. The position of the fourth loading platform 96 is changed as indicated by the arrow.

[0096] As mentioned, the transport devices 10 each have a signal transmitter 64 (see Figure 1B The signal transmitter 64 can issue a warning signal if the pallets 40 are so heavy that the maximum load of the relevant transport devices 10 is exceeded. The force measuring device 56 can detect that the maximum load has been exceeded.

[0097] Furthermore, from the Figure 9It is evident that the sensor units 66 of the transport devices 10 are oriented in opposite directions. One of the transport devices 10 detects the environment on one side of the pallet 40, while the other of the transport devices 10 detects the environment on the other side of the pallet 40. Reference symbol list

[0098] 10 Transport device 10 1 - 10 5 Transport device 12 Support structure 13 Housing 14 Outer contour 16 Chassis 18 First wheel 20 Second wheel 22 Drive unit 24 First drive motor 26 Second drive motor 28 First gearbox 30 Second gearbox 32 Lifting device 34 Spindle nut 36 Third drive motor 37 Spindle 38 Object 39 Support section 40 Pallet 42 Base 44 Studded mat 46 Tension sleeve 48 Disc housing 50 O-ring 52 Axial roller bearing 54 Rubber ring 56 Force measuring device 58 Force sensors 60 First group 62 Second group 63 Evaluation unit 64 Signal transmitter 66 Sensor unit 67 Camera 68 Sensor section 69 Ultrasonic sensor 70 Memory 71 Laser-based sensor 72 Bristle section 74 Self-stabilizing device 76 Communication device 78 Carrying handle 80 Groove 81 Transport system 82 Crossbeam 84 Board 86 Master 88 Slave 90 Master sensor unit 92 Workshop 94 Control unit 96 Loading platform 98 Spreader device 100 Spreader arm 102 Guide rail 104 Circular sector element 106 Adjustment unit 107 Additional drive unit 108 Toggle lever unit109 Drive train 110 Synchronizing unit 111 First gear 112 Cam disc 113 Second gear 114 Stop element 115 Decoupling unit 116 Support element 117 Cam disc 118 Spring 119 Bearing unit 120 Groove 121 Angle sensor 122 Pin 124 Output shaft 126 Clutch element 128 First face 130 Second face 132 First spur gear 134 Second spur gear 136 Return spring 138 Locking device 140 Stop AP plane outer surface AW curved outer surface D common axis of rotation D1 first axis of rotation D2 second axis of rotation R axis of rotation

Claims

1. Driverless transport system (81) for transporting objects (38), comprising - a plurality of driverless transport devices (10) comprising ∘ a support structure (12) having an outer contour (14) ∘ a chassis (16) that is fastened to the support structure (12) and has a least one first wheel (18) and one second wheel (20), wherein the first wheel (18) is mounted in the chassis (16) to be rotatable about a first axis of rotation (D1) and the second wheel (20) is mounted therein so as to be rotatable about a second axis of rotation (D2), ∘ a dive unit (22), by means of which the first wheel (18) and the second wheel (20) can be driven independently of one another, ∘ at least one support portion (39), which interacts with the objects (38) for transporting them, - a control unit (94) for controlling the driverless transport devices (10), and - a communication means (76), by which information can be exchanged between the control unit (94) and the driverless transport devices (10), wherein - one of the driverless transport devices (10) is configured as a master (86), and the remainder of the driverless transport devices (10) are configured as slaves (88), wherein - the master (86) comprises a master sensor unit (90) for sensing the surroundings of the master (86), and - the master (86) transmits information relating to the surroundings of the master (86) to the control unit (94) and / or to the slaves (88), characterised in that the master (86) is not provided for transporting the objects (38).

2. Driverless transport system (81) according to claim 1, characterised in that - each of the transport devices (10) in each case comprises a sensor unit (66) for sensing the surroundings of the transport device (10), wherein - the sensor unit (66) is arranged in a sensor portion (68) that is delimited by the outer contour (14) and the first axis of rotation (D1) and the second axis of rotation (D2), and - the sensor unit (66) is configured in such a way that it senses only the part of the surroundings on the side of the first axis of rotation (D1) or the second axis of rotation (D2), on which the sensor unit (66) is arranged, wherein - the sensor unit (66) of a first of the transport devices (10) is oriented towards the front in a direction of travel, and the sensor unit (66) of a second of the transport devices (10) is oriented towards the rear in the direction of travel.

3. Driverless transport system (81) according to either of the preceding claims, characterised in that one or more of the transport devices (10) comprise a force measuring means (56), by which the force acting on the support portion (39) can be determined.

4. Driverless transport system (81) according to any of the preceding claims, characterised in that - in plan view, the outer contour (14) of the support structure (12) is substantially rotationally symmetrical abut an axis of rotation (R), and - the support portion (39) and / or the first wheel (18) and the second wheel (20) are arranged within the outer contour (14) or end flush with the outer contour (14).

5. Driverless transport system (81) according to any of the preceding claims, characterised in that - the transport devices (10) comprise a sensor unit (66) for sensing the surroundings of the transport device (10), wherein - the sensor unit (66) is arranged in a sensor portion (68) delimited by the outer contour (14) and the first axis of rotation (D1) or the second axis of rotation (D2), and - the sensor unit (66) is configured in such a way that it senses only the part of the surroundings on the side of the first axis of rotation (D1) or the second axis of rotation (D2) on which the sensor unit (66) is arranged.

6. Driverless transport system (81) according to any of the preceding claims, characterised in that the transport devices (10) comprise a store (70) for electrical energy which, in plan view, protrudes in portions beyond the outer contour (14) of the support structure (12), wherein the store (70) is movably fastened on the support structure (12).

7. Driverless transport system (81) according to claim 6, characterised in that the store (70) is fastened to the support structure (12) so as to be rotatable about the axis of rotation (R).

8. Driverless transport system (81) according to claim 2 and either claim 6 or claim 7, characterised in that the store (70) is arranged outside the sensor portion (68).

9. Driverless transport system (81) according to any of claims 6 to 8, characterised in that the store (70) is detachably fastened to the support structure (12).

10. Driverless transport system (81) according to any of claims 6 to 8, characterised in that all the wheels (18, 20) are arranged so as to be rotatable about a common axis of rotation (D) and the driverless transport system (10) comprises a self-stabilising means (74).

11. Driverless transport device (10) according to any of the preceding claims, characterised in that the driverless transport devices (10) comprise a lifting means (32) for raising and lowering the at least one support portion (39), which interact with the objects for transporting them.

12. Method for operating a driverless transport system (81) according to any of the preceding claims, comprising the following steps: - specifying one of the driverless transport devices (10) as the master (86) and the remaining driverless transport devices (10) as slaves (88), - positioning the master (86) in such a way that o the master (86) is movable independently of the transported object (38), and o the surroundings of the master (86) can be sensed by means of the master sensor unit (90), and o transmitting information relating to the surroundings of the master (86) to the control unit (94) and / or to the slaves (88) by the communication means (76) which uses a wireless network, and o the wireless network is available for all the slaves (88).

13. Method for operating a driverless transport system (81) according to claim 12, wherein the transport system (81) comprises a plurality of transport devices (10) according to claim 12, said method comprising the following steps: - determining the force acting on the respective support portions (39) of the transport device (10) using the force measuring means (56), - transmitting the determined forces to the control unit (94) via the communication means (76), - comparing the determined forces by means of the control unit (94), and - raising or lowering one or more of the support portions (39) using the lifting means (32), depending on the comparison, when prompted by the control unit (94).

14. Method for operating a driverless transport system (81) according to claim 13, comprising the following steps: - transporting the object (38) with at least two transport devices (10), - sensing the surroundings of at least one transport device (10) by means of a sensor unit (66) with respect to selectable properties of the surroundings, and - raising or lowering the support portions (39) using the lifting means (32), depending on the sensed properties of the surroundings.