METHOD FOR MARKING A VEHICLE TIRE AND MARKING STATION

Description

[0001] The invention relates to a method for marking a vehicle tire according to the preamble of claim 1 and to a marking station for marking a vehicle tire according to the preamble of claim 8.

[0002] Tire test benches are known in the art, allowing vehicle tires to be subjected to a variety of different testing procedures. These include, in particular, measuring imbalance, uniformity, cone value, and tire geometry. The determined parameters are then applied to the tire as markings, e.g., colored dots, and identify the vehicle tires according to quality levels. Depending on requirements, the colored dots can be applied to any externally visible area of ​​the vehicle tire, except for the tire tread.

[0003] WO 2015 / 086187 A1 discloses a method for automatically marking a tire after the tire has already left a tire testing machine. The tire to be marked is fed directly via conveyor belts to the marking station, which is located directly downstream of the measuring machine.

[0004] US 2013 / 233067 A1 discloses a tire test bench with a marking station for the automated changing of test rims. The test rims consist of two axial halves. Each test rim is suitable for a specific tire size, so that a rim change may be necessary to test different tire sizes. The tire test bench of US 2013 / 233067 A1 may also include a marking station (not described in detail) and a sorting station (also not described in detail).

[0005] WO 2011 / 143175 A2 discloses a system for assembling vehicle wheels. A robotic arm of the system removes a rim from a rim warehouse, places a valve in the rim, and finally installs the rim in a tire.

[0006] The thus assembled vehicle wheel is then passed by the robot arm to a tire inflation station, where it is filled with compressed air. The vehicle wheel is then subjected to a balancing test. Depending on the balancing behavior, the vehicle wheel is marked accordingly. Furthermore, a method is disclosed according to which the vehicle wheel is placed by the robot arm at different stations for further processing depending on the result of the balancing test.

[0007] From DE 10 2015 222 865 A1 a method for marking and sorting tires and for changing test rims for the tires by means of a robot known per se is known, in which the robot picks up the tested tires and feeds them to a marking device so that a marking describing the quality of the tire can be applied to the tire by the marking device.

[0008] EP3269569 A1 describes a method and a device for maintaining vehicle wheels. The method provides for a vehicle wheel to be mounted on a support of the device, the wheel comprising a rim and a tire. Furthermore, a digital code is created for uniquely identifying the tire. Finally, a marking system, preferably of an optical type, generates at least one marking on the surface of a sidewall of the tire of the wheel, which corresponds to the previously created digital code.

[0009] A problem underlying the invention is to meet the requirements existing in tire production and in the vehicle manufacturing industry regarding the shapes, colors and number of marking points on the vehicle tires to be marked with the least possible equipment expenditure and short processing times.

[0010] This object is achieved according to the invention by the method for marking a vehicle tire according to claim 1. Advantageous embodiments and further developments of the invention emerge from the dependent claims.

[0011] The invention relates to a method for marking a vehicle tire, wherein the vehicle tire is fed to a marking station, wherein the vehicle tire is aligned and centered in the marking station, wherein the marking is performed in the marking station according to the properties of the vehicle tire, and wherein the marking is performed using one of a plurality of different marking devices. The method according to the invention is characterized in that the marking device for marking the vehicle tire is positioned on the vehicle tire by means of a robot arm.

[0012] A method is thus provided that enables the marking of a vehicle tire according to its properties. The properties of the vehicle tire preferably describe one of several possible quality levels of the vehicle tire, for example, "very good," "good," and "average." Further or different quality levels are also conceivable. The quality levels, in turn, preferably represent an imbalance exhibited by the respective vehicle tire in its running behavior. The smaller the imbalance, i.e., the better the running behavior of the vehicle tire, the higher the quality level is advantageously.

[0013] Alternatively, the properties of the vehicle tire may also preferably describe a noise behavior of the vehicle tire, a road grip of the vehicle tire, a permissible maximum speed of the vehicle tire or other properties of the vehicle tire, which can be applied as a marking on the vehicle tire in addition to or alternatively to the running behavior of the vehicle tire.

[0014] The marking can, for example, be a color marking or an embossed marking. In the case of a color marking, different quality levels are preferably represented by different colors. In the case of an embossed marking, different quality levels are preferably represented by different embossed symbols. A combination of color markings and embossed markings is also possible and preferred. It is also possible and preferred to provide a specific marking material to indicate a specific quality level.

[0015] The vehicle tire is preferably a so-called PCR (Passenger Car Radial Tire) tire or a so-called TBR (Truck and Bus Radial Tire) tire.

[0016] The vehicle tire is advantageously fed to the marking station immediately after testing its properties, for example, via a conveyor belt. The vehicle tire is therefore tested in particular prior to the method according to the invention for marking the vehicle tire in a test station designed for this purpose.

[0017] After the vehicle tire is fed to the marking station, for example via a conveyor belt, the vehicle tire is first aligned and centered by the marking station.

[0018] The term "centering" refers to bringing the rotational axis of the vehicle tire into a desired position, thus positioning the vehicle tire in the desired position. The vehicle tire is then positioned centrally on a turntable. If the radial diameter of the vehicle tire is known, the marking can now be applied to the specified radial position. Centering of the vehicle tire is preferably automated using a centering arm that can move the tire on the turntable.

[0019] The term "alignment" refers to the process of bringing the vehicle tire into a specified angular position with respect to its rotational axis. This allows the marking to be applied at the specified angular position. The alignment of the vehicle tire is preferably carried out automatically via the turntable.

[0020] The actual marking of the vehicle tire is then carried out using a specific marking device from the multitude of different marking devices, with each marking device producing a different mark. Thus, by selecting a specific marking device, it is possible to determine which mark should be applied to the vehicle tire.

[0021] Advantageously, it can also be provided that each marking device can produce more than one mark; for example, it may be possible for a marking device to produce two, three, or more different marks. The two, three, or more different marks of a marking device can preferably be applied independently of one another and in accordance with information from the testing process.

[0022] According to the invention, the marking device for marking the vehicle tire is positioned on the vehicle tire by means of a robot arm. This means that - in contrast to the prior art - the vehicle tire is not picked up and fed to the marking device, but rather the marking device is picked up and fed to the vehicle tire. This advantageously reduces the required device expenditure, since the marking devices not picked up by the robot arm and required for marking can be set aside by the robot arm and do not have to be kept ready in the area of ​​the marking station so that they are accessible to the vehicle tire. The marking station according to the invention is therefore significantly more compact and also more cost-effective than known marking stations.This also makes it possible to provide a comparatively larger number of marking devices and thus a correspondingly larger number of possible different markings, which in turn expands the application possibilities of such a marking station compared to known marking stations, in particular without the need for conversions and the associated conversion times of the marking station.

[0023] In addition, it has been shown that the throughput times of the marking station according to the invention are reduced compared to the throughput times of the known marking stations, i.e. that the method according to the invention for marking a vehicle tire results in a time saving compared to the known methods.

[0024] Furthermore, the use of the robot arm offers the advantage that other work steps not directly related to the vehicle tire, such as changing the test rims, can also be performed by the robot arm. The test rims, each consisting of an upper and a lower test rim half, are changed independently of any marking or testing process, i.e., whenever a vehicle tire of a different size is to be tested in the test station. In this case, the robot arm exchanges the clamped test rim halves for other test rim halves of a different diameter.

[0025] For the purposes of the invention, a robot arm is understood to be a so-called NC-axis system, which can be designed either as a commercially available robot known in the prior art or as a freely configurable linear axis system. The robot arm is advantageously designed to be rotatable about a vertical axis of rotation and comprises several joints that enable at least one rotary movement of arm elements about a horizontal axis of rotation, but in particular also about a vertical axis of rotation. Furthermore, the robot arm advantageously comprises a tool changing system, which can be designed, for example, as a gripper, in particular as a three-finger gripper, by means of which the robot arm can pick up, actuate, and then set down a required marking device.

[0026] The robot arm preferably has six axes of movement. An example of a preferred robot type is available on the market under the name KR QUANTEC Pro from the manufacturer KUKA available.

[0027] According to the claimed invention, it is provided that the plurality of different marking devices are stored in a marking device magazine and that the robot arm selects and receives a specific marking device from the plurality of different marking devices. The marking device magazine can be designed, for example, like a shelf that stores the plurality of different marking devices next to and above one another in positions provided for them. The robot arm knows the individual position of each individual marking device and can therefore remove it from the marking device magazine in a targeted manner and also replace it again. The marking device magazine enables space-saving storage within reach of the robot arm while simultaneously ensuring individual positions in the marking device magazine for each individual marking device.

[0028] Preferably, several marking device magazines can also be provided, which are either all arranged within reach of the robot arm or can be moved automatically, for example via a rail system, so that at least one marking device magazine with a required marking device is always within reach of the robot arm.

[0029] According to a further preferred embodiment of the invention, when changing the marking device, the robot arm deposits a no longer required marking device in the marking device magazine at a position assigned to the no longer required marking device. This allows this marking device to be later retrieved from its individually assigned position, which is known to the robot arm.

[0030] According to a further preferred embodiment of the invention, the marking device is supplied with electrical and / or thermal energy for a variety of marking processes during its storage period. Depending on the design of the marking device for applying color markings, embossed markings, or material markings, it may be necessary to supply the marking device with electrical or thermal energy. The supply of thermal energy can, for example, be achieved by heating an embossing die of a marking device intended for applying embossed markings via an external heat source during the storage period in the marking device magazine. Furthermore, such a marking device can also comprise an electrical energy storage unit, by means of which the embossing die continues to be heated after removal from the marking device magazine.However, it is also conceivable that marking devices intended for applying color markings or material markings require electrical energy, which is provided via the electrical energy storage unit during operation of the respective marking device.

[0031] The electrical energy storage unit is preferably designed as a rechargeable lithium-ion storage device.

[0032] The supply of electrical energy in the marking device magazine can, for example, be carried out wirelessly by means of induction or via corresponding electrical contacts of the marking device magazine and the respective marking device, which come into contact with each other when the marking device is deposited in the marking device magazine.

[0033] According to a further preferred embodiment of the invention, the alignment and centering are performed at least partially simultaneously. This allows the throughput times of the marking station according to the invention to be further reduced.

[0034] According to a further preferred embodiment of the invention, the properties of a plurality of vehicle tires are determined simultaneously in a plurality of testing stations. Since a testing process is generally more time-consuming than a marking process, the utilization of a marking station executing the method according to the invention can be increased if a plurality of testing stations are provided, which simultaneously determine the respective properties of a plurality of vehicle tires to be examined in a plurality of testing processes. This plurality of vehicle tires is then equally fed to the marking station executing the method according to the invention.

[0035] According to a further preferred embodiment of the invention, information about the properties of the vehicle tire is also supplied during the supply process. The information is preferably supplied electronically via a data processing program designed for this purpose, which first records the information from the vehicle tire testing process and then transmits it to the marking station. The information allows at least the selection of a specific marking device from the multitude of different marking devices, the determination of an angular position, and the determination of a radial position for applying the marking.

[0036] According to a further preferred embodiment of the invention, a tire wall of the vehicle tire is supported on an inner side of the vehicle tire, at least during the marking process. This simplifies the application of the marking, as it prevents the tire wall from yielding or bending. The vehicle tire can be supported, for example, by a correspondingly designed support body, which is, in particular, automatically inserted into the interior of the vehicle tire.

[0037] The invention further relates, as defined in claim 8, to a marking station for marking a vehicle tire, comprising a robot arm and a plurality of different marking devices, wherein the marking devices are stored in at least one marking device magazine, and wherein the robot arm is designed to mark the vehicle tire according to properties of the vehicle tire using a marking device from the plurality of different marking devices. The marking station according to the invention for marking a vehicle tire is characterized in that the robot arm is further designed to position the marking device for marking the vehicle tire on the vehicle tire. The marking station according to the invention for marking a vehicle tire thus comprises all the means required to carry out the method according to the invention and thus leads to the advantages already described.

[0038] According to a preferred embodiment of the invention, the plurality of marking devices is at least partially configured as a plurality of hot-stamping devices. Hot-stamping devices enable the application of embossed markings that are particularly robust and durable.

[0039] According to a further preferred embodiment of the invention, the plurality of marking devices is at least partially equipped with an electrical energy storage unit. Thus, a corresponding marking device can draw the electrical energy required during operation from the energy storage unit and does not need to be supplied with electrical energy via the robot arm during operation. Possible energy requirements can be, for example, a heating device for heating a hot stamping die, the actuation of an ink stamp, the operation of a microcontroller, or other electronic components of the marking device.

[0040] According to a further preferred embodiment of the invention, the at least one marking device magazine and the plurality of marking devices are designed to charge each of the electrical energy storage units with electrical energy via a charging process while the plurality of marking devices is located in the at least one marking device magazine. Charging with electrical energy preferably takes place via corresponding electrical contacts of the marking device magazine and the respective marking device, which come into contact with one another when the marking device is deposited in the marking device magazine.

[0041] According to a particularly preferred embodiment of the invention, the charging process is contactless, particularly inductive. Thus, it is not necessary to provide a specific interface in the form of coordinated electrical contacts.

[0042] According to a further preferred embodiment of the invention, the plurality of electrical marking devices each has a thermal energy storage unit. The thermal energy storage unit can be designed, for example, as a metallic body having a comparatively high heat capacity and in contact with the hot stamping die. Thus, the temperature of the hot stamping die can be maintained for a comparatively long time within the temperature range required for hot stamping, which in turn correspondingly extends the uninterrupted operating time of such a marking device.

[0043] According to a particularly preferred embodiment of the invention, the at least one marking device magazine and the plurality of marking devices are designed to charge each of the thermal energy storage units with thermal energy via a charging process while the plurality of marking devices is located in the at least one marking device magazine. For this purpose, the at least one marking device magazine can, for example, have a heat source which, when the respective marking device is deposited at its individual position, comes into contact with the hot stamping die and thus supplies heat to the hot stamping die and to the thermal energy storage unit, which is also in contact with the hot stamping die.

[0044] The invention is explained below by way of example with reference to embodiments shown in the figures.

[0045] They show: Fig. 1 shows an exemplary and schematic illustration of a marking station according to the invention for marking a vehicle tire, and Fig. 2 shows an exemplary and schematic illustration of a possible embodiment of a method according to the invention for marking a vehicle tire in the form of a flow chart.

[0046] Identical objects, functional units and comparable components are designated with the same reference symbols throughout the figures. These objects,

[0047] Functional units and comparable components are identical in terms of their technical features, unless the description explicitly or implicitly states otherwise.

[0048] Fig. 1shows, by way of example and schematically, a marking station 10 according to the invention for marking a vehicle tire 20. The marking station 10 comprises a robot arm 11 and a plurality of different marking devices 12, of which, for the sake of clarity, only a single marking device 12 is shown in Fig. 1 As can be seen, the marking device 12 is stored in a marking device magazine 13, wherein the marking device magazine 13 is designed to store a plurality of marking devices 12, each at an individual position. The marking device magazine 13 also has electrical contacts 13' for each marking device 12, which are connected via correspondingly designed counter contacts (not shown in Fig. 1 ) of the marking devices 12 on the one hand charge an electrical energy storage device of the marking devices 12 and also a hot stamping stamp (also not shown in Fig. 1) of the marking devices 12 via a heating spindle structurally integrated into the marking devices 12.

[0049] The marking station 10 further comprises, for example, a turntable 14 for aligning the vehicle tire 20, i.e., for setting a predetermined angular position with respect to the rotation axis of the vehicle tire 20. Furthermore, the marking station 10 comprises a centering arm 15 that can move the vehicle tire 20 on the turntable 14 so that it is centered on the turntable 15. After alignment and centering, which, for example, occur simultaneously, the vehicle tire 20 is in the predetermined position and in the predetermined angular position.

[0050] The robot arm 11 is configured, for example, with six axes of movement. Furthermore, it is configured to remove a required marking device 12 from the marking device magazine 13, use it to mark the vehicle tire 20, and then return it to the position in the marking device magazine 13 from which the marking device 12 was previously removed. The marking of the vehicle tire 20 is thus performed by the robot arm 11 picking up a required marking device 12 from the marking device magazine 13, guiding it to the vehicle tire 20, positioning it on the vehicle tire 20, and then marking the vehicle tire 20 using the marking device 12. The marking of the vehicle tire 20 is performed according to the properties of the vehicle tire 20 using a marking representing the properties or a corresponding marking device 12.

[0051] Since the vehicle tire 20 is in a position and angular position intended for applying the marking after alignment and centering, the robot arm 11 can move the marking device 12 to the vehicle tire 20 and there apply the marking corresponding to the quality of the vehicle tire 20 at the designated location on the vehicle tire 20.

[0052] In order for the robot arm 11 to pick up the required marking device 12 and use it to apply the marking, information about the properties of the vehicle tire 20 is electronically fed to the marking station 10 via a data processing program designed for this purpose as part of the feeding of the vehicle tire 20. The data processing program first records information from the testing process of the vehicle tire 20 and then transmits it to the marking station 20. The information then allows a specific marking device 12 to be selected from the multitude of different marking devices 12. After the vehicle tire 20 has been fed to the marking station 10, for example via a conveyor belt, the vehicle tire 20 is aligned and centered by the marking station 10.

[0053] Furthermore, the marking station 10 also comprises a support body 16, which is automatically moved into the interior of the vehicle tire 20 during the marking by the robot arm 11 or by the marking device 12 and from there supports the tire wall on which the marking is applied.

[0054] Finally, the marking station 10 also comprises a conveyor belt 17 by means of which the vehicle tire 20 is, for example, transported from one or more testing stations (not shown in Fig. 1 ) is fed to the marking station 10. The test stations first determine the properties of the vehicle tire 20, and the marking station 10 applies a marking on the vehicle tire 20 that describes the properties of the vehicle tire 20.

[0055] Fig. 2shows, by way of example and schematically, a possible embodiment of a method according to the invention for marking a vehicle tire 20 in the form of a flow chart. In a first method step 100, the vehicle tire 20 is fed to a marking station 10 according to the invention. At the same time, in step 101, information describing a quality level of the vehicle tire 20 is fed to the marking station 10. In step 102, the vehicle tire 20 is then aligned, and in step 103, the vehicle tire 20 is centered. In step 104, a support body 16 is inserted into the interior of the vehicle tire 20. In step 105, the robot arm 11 selects a marking device 12 from the marking device magazine 13. Steps 102, 103, 104, and 105 occur simultaneously, for example.In step 106, the robot arm 11 picks up the selected marking device 12, guides it to the vehicle tire 20 in step 107, and positions it on the vehicle tire 20. Finally, in step 108, the actual marking takes place according to the quality level of the vehicle tire 20. Reference symbol

[0056] 10 Marking station 11 Robot arm 12 Marking device 13 Marking device magazine 13 Electrical contacts 14 Turntable 15 Centering arm 16 Support body 17 Conveyor belt 20 Vehicle tire 100 Feeding the vehicle tire 101 Feeding information describing a quality level of the vehicle tire 102 Aligning the vehicle tire 103 Centering the vehicle tire 104 Inserting a support body 105 Selecting a marking device 106 Picking up the selected marking device 107 Positioning the marking device on the vehicle tire 108 Marking the vehicle tire

Claims

1. Method for marking a vehicle tyre (20), wherein the vehicle tyre is supplied (100) to a marking station (10), wherein the vehicle tyre (20) is aligned and centred (102, 103) in the marking station (10), wherein the marking (108) takes place in the marking station (10) according to properties of the vehicle tyre (20), wherein the marking (108) takes place by means of a marking device (12) from a plurality of different marking devices (12), and wherein the marking device (12) for marking the vehicle tyre (20) is positioned (107) on the vehicle tyre (20) by means of a robot arm (11), characterized in that the plurality of different marking devices (12) are stored in a marking device magazine (13) and in that the robot arm (11) selects and picks up (105, 106) a specific marking device (12) from the plurality of different marking devices (12).

2. Method according to Claim 1, characterized in that, when changing the marking device (12), the robot arm (11) deposits a no longer required marking device (12) in the marking device magazine (13) at a position assigned to the no longer required marking device (12).

3. Method according to at least one of Claims 1 and 2, characterized in that the marking device (12) is supplied with electrical and / or thermal energy for a plurality of marking procedures during the time that it is being deposited.

4. Method according to at least one of Claims 1 to 3, characterized in that the aligning and the centring (102, 103) take place at least partly simultaneously.

5. Method according to at least one of Claims 1 to 4, characterized in that properties of a plurality of vehicle tyres (20) are determined simultaneously in a plurality of testing stations.

6. Method according to at least one of Claims 1 to 5, characterized in that information about the properties of the vehicle tyre (20) is also supplied as part of the supplying (101).

7. Method according to at least one of Claims 1 to 6, characterized in that a tyre wall of the vehicle tyre (20) is supported (104) on an inner side of the vehicle tyre (20) at least during the marking.

8. Marking station (10) for marking a vehicle tyre (20), comprising a robot arm (11) and a plurality of different marking devices (12), wherein the robot arm (11) is furthermore designed to position the marking device (12) for marking the vehicle tyre (20) on the vehicle tyre (20), characterized in that the robot arm (11) is designed to mark the vehicle tyre (20) according to properties of the vehicle tyre (20) by means of a marking device (12) from the plurality of different marking devices (12) and the marking devices (12) are stored in at least one marking device magazine (13).

9. Marking station (10) according to Claim 8, characterized in that the plurality of marking devices (12) at least in part take the form of a plurality of heat embossing devices (12).

10. Marking station (10) according to at least one of Claims 8 and 9, characterized in that the plurality of marking devices (12) at least in part feature an electrical energy storage unit.

11. Marking station (10) according to Claim 10, characterized in that the at least one marking device magazine (13) and the plurality of marking devices (12) are designed to charge the respective electrical energy storage unit with electrical energy via a charging procedure whilst the plurality of marking devices are situated in the at least one marking device magazine.

12. Marking station (10) according to Claim 11, characterized in that the charging procedure takes place contactlessly.

13. Marking station (10) according to at least one of Claims 8 to 12, characterized in that the plurality of electrical marking devices (12) each feature a thermal energy storage unit.

14. Marking station (10) according to Claim 13, characterized in that the at least one marking device magazine (13) and the plurality of marking devices (12) are designed to charge the respective thermal energy storage unit with thermal energy via a charging procedure, whilst the plurality of marking devices (12) are situated in at least one marking device magazine (13) .