CONVEYOR SYSTEM OF A PRODUCTION CELL

Description

[0001] The invention relates to a conveying system of a manufacturing cell with a stationary control module and with at least one rail- or track-bound self-driving vehicle, as well as a manufacturing cell with a programmable logic controller and with a conveying system.

[0002] German patent DE 10 2017 012 077 A1 discloses a conveyor system with workpiece carriages that can travel along a support rail. Machining of the workpieces can lead to interference with data and signal transmission.

[0003] From EP 3 170 776 A1, a conveying device is known with a stationary control unit, conveying units having a master communication interface, and conveying units having a slave communication interface. Each vehicle has a control unit that controls a load-handling device carried on the vehicle. The control unit can periodically request the conveying units to transmit position data.

[0004] The present invention is based on the problem of increasing the reliability of the conveying system.

[0005] This problem is solved by the features of the main claim. For this purpose, the control module has at least one antenna for bidirectional wireless transmission of data and signals between the vehicle and the control module. The vehicle has at least one antenna, which is assigned to a drive unit of the vehicle. The drive unit has a converter for converting a data set transmitted by the control module in a protocol format into digital control signals for a drive motor of the drive unit. Furthermore, the drive unit has a speed-related sensor, and the drive unit is configured to transmit the output signal of this speed-related sensor to the control module in a protocol format, so that the control module regulates the vehicle's driving profile in real time in a closed loop.

[0006] In the manufacturing cell, the control module is connected to the programmable logic controller.

[0007] The control module regulates the movement of all connected vehicles in the production cell. For this purpose, a driving profile is transmitted to each individual vehicle. This driving profile includes values ​​for acceleration, travel speed, and distance. Based on feedback from the current state of each vehicle, the control module calculates and transmits new target values. The transmitted data is stored in protocol format and is transmitted wirelessly between the control module and each individual vehicle in both directions.

[0008] Each handling device, for example, which is assigned to at least one vehicle, has an internal control loop with a controller, a measuring element, and a gripper sequence program memory. To start a gripper sequence program, binary identification and start signals are wirelessly transmitted from the memory module to the handling device. When the gripper sequence program is completed, a status signal is wirelessly transmitted from the handling device to the control module. This establishes a point-to-point connection for information transmission between the respective sender and receiver.

[0009] This eliminates the need to lay data and signal cables in the production hall and along the vehicle. Electrical resistance at the contact points of the signal and data cables, caused by contamination, is prevented.

[0010] Further details of the invention will become apparent from the dependent claims and the following description of schematically illustrated embodiments. Figure 1: Manufacturing cell; Figure 2: Control module; Figure 3: Workpiece trolley with power rail; Figure 4: Workpiece trolley; Figure 5: Workpiece trolley without housing; Figure 6: Block diagram of the conveyor system control.

[0011] The Figures 1 to 5Figure 10 shows a manufacturing cell and its individual components. The manufacturing cell (10) is, for example, part of a flexible manufacturing system. In the flexible manufacturing system, workpieces (211, 212) are fed to various, unlinked stations for multi-stage processing. After completion of a machining operation, the individual workpiece (211; 212) is conveyed to the next manufacturing cell (10) or manufacturing station, depending on the sequence and type of machining operations required for the workpiece. However, complete machining of a workpiece (211; 212) can also be carried out in a single manufacturing cell (10). The individual machining operation can, for example, be forming, cutting, and / or joining.

[0012] The workpieces (211, 212) processed in the illustrated manufacturing cell (10) are plate- or board-like. The material of the workpiece (211, 212) can be wood, metal, a composite material, glass, plastic, etc. It can have a constant cross-section along its length oriented in the longitudinal direction (15). However, it is also conceivable to use, for example, a pre-machined workpiece, an already assembled sub-assembly, etc., as the workpiece (211, 212). In the following, the manufacturing cell (10) with a wooden panel as the workpiece (211; 212) is described. This panel (211; 212) has, for example, a length of three meters, a width of 600 millimeters, and a thickness of 25 millimeters.

[0013] The illustrated manufacturing cell (10) comprises a first processing station (40), a second processing station (60), and a workpiece transport device (81). The workpiece transport device (81) is part of a conveying system (80) of the manufacturing cell (10). The two processing stations (40, 60) are connected in series in the material flow. A workpiece (211; 212) can be conveyed by means of the conveying system (80) from an insertion area (31) to the first processing station (40), to the second processing area (60), and to a removal area (201). For this purpose, the workpiece (211; 212) is inserted into handling devices (121) of track-bound or rail-bound vehicles (100; 130) of the conveying system (80), which transport the workpiece (211; 212) through the manufacturing cell (10). In the illustrated embodiment, the vehicles (100; 130) are track-bound workpiece trolleys (100; 130).The manufacturing cell (10) can also have more than two processing stations (40, 60).

[0014] The manufacturing cell (10) has, for example, a central programmable logic controller (PLC) (141) that coordinates the functions of all processing stations (40, 60), the conveyor system (80), and other functions. This PLC is housed, for example, in a control cabinet (140). The individual functions are controlled, for example, by means of sub-controllers. For the conveyor system (80), for example, the control module (150) shown in Figure 2 is used. This is also located, for example, in the control cabinet (140). It is connected to the higher-level functional modules of the PLC (141), for example, by means of data lines (155).

[0015] The Figure 6Figure 80 shows a simplified block diagram of the conveyor system control. The control module (150) has a program memory (151), a controller (152), a converter (153), and a transmitter / receiver (154). Driving programs for the vehicles (100; 130) are stored in the program memory (151) and can be retrieved. These programs contain, for example, all parameters required for a driving command. These include, for example, acceleration during starting and deceleration, speed, and time specifications for the individual parameters. Waypoints may also be stored. The individual driving programs can be retrieved individually for each vehicle (100; 130) or for groups of vehicles (100; 130).

[0016] The controller (152) has three controller inputs (156-158) and one controller output (159). The data line (155) is connected to the first controller input (156). Among other things, commands to start the control loop of the conveyor system (80) are transmitted via this data line (155). In the opposite direction, confirmation messages for the completion of travel orders or partial travel orders are transmitted, for example.

[0017] The program memory (151) is connected to the second controller input (157). The second controller input (157) is, for example, a setpoint input (157).

[0018] The third controller input (158) is a measured value input (158). A measured value determined at the controlled system (161) is fed to the controller (152) here. This measured value may be processed and / or compressed. In the exemplary embodiment, the measured value is, for example, a value of the vehicle's speed (100; 130) and / or a value derived from it, such as the distance traveled or the acceleration.

[0019] The control signals are output at the controller output (159) to the controlled system (161). The controlled system (161) of this control loop is the vehicle's movement (100; 130) relative to the track support (11). For this purpose, the control signals are transmitted in a first transmission direction (191) to a converter (153). In the converter (153), the received digital data is converted into a protocol format. This protocol format is, for example, a data format according to IEC EN 61131 Part 9 for communication over a point-to-point connection. The use of a different protocol format is also conceivable. The converter (153) can be a network processor. If necessary, different converters can be used to forward data in different protocol formats. It is also conceivable to transmit individual data, e.g., binary data, without conversion.

[0020] The signal travels from the transmitter-receiver (154) towards the measured value input (158) of the controller (152) in a second transmission direction (192), which is oriented opposite to the first transmission direction (191). In the second transmission direction (192), the data packet arriving in protocol form is converted into digital data in the converter (153). Instead of a single converter (153), two separate converters (153) can also be used for the two transmission directions (191, 193; 192, 194).

[0021] The data set coming from the controller (152) is fed by the converter (153) in the converted data format along a data line (162) to the transmitter-receiver (154). The data line (162) can be an unshielded three-core cable. The transmitter-receiver (154) has a modulator-demodulator (163) and an antenna (164). The transmitter-receiver can also have, for example, at least one high-frequency generator, at least one amplifier, and at least one filter assembly. In the first transmission direction (191), for example, a high-frequency carrier signal is modulated in the modulator-demodulator (163) using the data protocol. The modulated signal is radiated by means of the antenna (164). The radiation occurs, for example, in a frequency range of 2.4 gigahertz. Radiation in the range of 3.6 gigahertz, 5.8 gigahertz, etc., is also conceivable. The antenna (164) can be arranged offset from the control cabinet (140) in the production hall.

[0022] In the second transmission direction (192), for example, the same transceiver (154) is used. The data packets received by the antenna (164) are demodulated in the transceiver (154) by means of the modulator-demodulator (163). The low-frequency data packet is then routed, for example, via the data line (162) to the converter (153).

[0023] Instead of the described transceiver (154) with a transmit branch and a receive branch, a separate transmitter and receiver can also be used. The transmitter then has the modulator. The receiver has a demodulator. The same antenna (164) can be used for both the transmitter and the receiver. However, it is also conceivable to use separate antennas for transmitting and receiving.

[0024] In the production hall, more than one antenna (164) can be provided for transmitting the modulated signal. Each antenna (164) is then assigned a modulator-demodulator (163) or a modulator. Different carrier frequencies are used, for example, for modulating the individual transmitters.

[0025] Multiple antennas can also be used for receiving signals. These can be connected to a common modulator-demodulator (163) or a common demodulator. However, it is also conceivable to assign a modulator-demodulator (163) or a demodulator to each receiving antenna or group of receiving antennas.

[0026] When using a single antenna (164) for both transmitting and receiving, a signal is either transmitted or received in a given sequence. The switch between transmitting and receiving can occur, for example, within milliseconds. When using separate antennas for the transmitting and receiving branches, transmitting and receiving can occur simultaneously. In this case, the transmitting and receiving frequencies are, for example, spaced far enough apart to prevent interference.

[0027] The manufacturing cell (10) shown in the figures above has a rail support body (11) oriented in the longitudinal direction (15), on which a guide grid (12), a transport track (82) and a return track (83) are arranged.

[0028] Both the transport track (82) and the return track (83) are longitudinally oriented (15) straight rails (82; 83) for ball bearing shoes (101). They have an identical cross-sectional profile. A rack (19) and electrical conductors (21-25) are arranged below each of the transport track (82) and the return track (83). Turntables (13, 14) are arranged at both ends of the rail support body (11) for transferring the workpiece carriages (100; 130) from the transport rail (82) to the return rail (83) and vice versa. Alternatively, the workpiece carriages (100; 130) can be moved parallel between the support rails (82, 83) instead of the turntables (13, 14). A continuous rail is also conceivable with appropriate design of the workpiece carriage rail supports (100; 130). For a rail-bound vehicle (100; 130), this could, for example, run along the hall floor.It can be driven as a forklift along a rail, an induction loop, etc. In the case of rail-bound guidance of the vehicle (100, 130), the guidance can also be virtual.

[0029] The guide grid (12) is, for example, arranged at an angle of 10 degrees to a vertical plane. It can also be arranged vertically. The guide grid (12) maintains a constant distance from the transport rail (82). In the longitudinal direction (15), it is interrupted in the area of ​​two support devices (41, 61). For example, it limits the working area of ​​the processing stations (40, 60) in a transverse direction (16).

[0030] The individual workpiece trolleys (100; 130), see the Figures 3-5 They are, for example, identically designed. More or fewer than the number of workpiece trolleys shown (100; 130) can also be used.

[0031] Each workpiece carriage (100; 130) has a recirculating ball bearing (101) that engages the respective support rail (82; 83). Below the recirculating ball bearing (101), each workpiece carriage (100; 130) has a motor-driven drive wheel (115) that meshes with the rack (19). For power supply, the workpiece carriage (100; 130) has, for example, sliding contacts (103–107) that contact the electrical conductors (21–25). Inductive power transfer is also conceivable. The workpiece carriages (100; 130) are self-propelled.

[0032] In the illustrated embodiment, five conductor tracks (21-25) are arranged on both sides of the rail support body (11). A DC voltage of 48 volts is present between the uppermost two conductor tracks (21, 22). This voltage potential is referred to below as the load voltage. A DC voltage of 24 volts exists between the third conductor track (23) and the fourth conductor track (24). This voltage potential is referred to below as the control voltage. The fifth conductor track (25) is at ground potential. For example, it is connected to the ground connection of the production hall at a neutral point.

[0033] On the vehicle side, each conductor track (21-25) is assigned a sliding contact (103-107). All sliding contacts (103-107) are of identical construction and are held, for example, by a parallelogram linkage (108). They are spring-loaded in the direction facing away from the housing (109) of the workpiece carriage (100; 130). In the exemplary embodiment, the load voltage circuit is designed to be separate from the control voltage circuit, at least on the vehicle side. The housing (109) is at ground potential.

[0034] It is also conceivable to transmit only the control voltage or only the load voltage, in addition to the ground potential, via the conductor tracks (21-25) and the sliding contacts (103-107). Any additional voltage potential that may be required can then be generated from this voltage, for example, by means of a voltage divider or a voltage multiplier. At least one accumulator can also be arranged in or on the vehicle (100; 130). The vehicle (100; 130) then has a mobile power source. This can be permanently installed or quickly replaceable. The accumulator can be recharged at a maintenance station. The only electrical connection between the vehicle (100; 130) and the rail support structure (11) is then the equipotential bonding of the ground potential.

[0035] The individual workpiece carriage (100; 130) has a drive unit (111) and, for example, at least one handling device (121). The drive unit (111) is arranged in a housing (109) on which the handling device (121) is mounted. A rear cover (112) closes the housing (109) in the area of ​​the drive unit (111). This cover (112) can be made, for example, of plastic, glass, or another non-metallic material.

[0036] The drive unit (111) has a flange support (113) that carries a drive motor (114) and the drive wheel (115) driven by it. The drive motor (114) is, for example, a servo motor (114) that is individually controlled, for example, via a control assembly (170). The drive wheel (115) is coupled to the drive motor (114), for example, via a multi-stage rolling gear. In the illustrated embodiment, the drive wheel (115) has helical teeth.

[0037] A lubrication wheel (116) is rotatably mounted in the flange support (113) at a distance from the drive wheel (115). The lubrication wheel (116) also has helical teeth and meshes with the rack (19) during operation. For example, the lubrication wheel (116) is designed as a felt wheel. The lubrication wheel (116) can have a different diameter than the drive wheel (115). For example, the flanks of the lubrication wheel (116) are lubricated with a lubricant, e.g., oil from a lubrication unit, via a lubrication wheel shaft mounted in the flange support (113). This lubricant is transferred to the rack (19) during rolling. Other rack lubrication configurations are also conceivable.

[0038] In this embodiment, the drive motor (114) is connected to the load voltage potential. The components of the control assembly (170) arranged in the housing (109) are electrically connected to the control voltage potential. In this embodiment, the control assembly (170) comprises a transceiver (171) with an antenna (172), a converter (174), and optionally a microcomputer. In this embodiment, the antenna (172) is located near the cover (112) in the housing (109) of the workpiece carriage (100; 130). The signals received by the control module (150) via the antenna (172) are demodulated by a demodulator-modulator (173) and transmitted along a data line to the converter (174). The demodulator-modulator (173) and the converter (174) can, for example, be constructed in the same way as the components described in connection with the control module (150). The digital signals transmitted from the converter (174) to the drive motor (114) control, for example,the drive current of the drive motor (114).

[0039] The drive unit (111) also has at least one speed-related sensor (117). This is, for example, an absolute rotary encoder mounted on the motor shaft of the drive motor (114). Its analog output signal is converted into a protocol format, for example, in the converter (174). The data protocol can correspond to the data protocol mentioned above. The converted signal is modulated onto a carrier and transmitted via the antenna (172). The transmitter and receiver for controlling the drive unit (111) can also be separate components.

[0040] At least one distance sensor (136) can be arranged on the workpiece carriage (100; 130). This sensor is oriented, for example, in the direction of travel (135) of the workpiece carriage (100; 130). If, for example, an obstacle is detected by means of the distance sensor (136), the workpiece carriage (100; 130) is slowed down or stopped.

[0041] Above the ball screw (101), the individual workpiece carriage (100; 130) has a handling device (121). The handling device (121) is, for example, interchangeably attached to a basic assembly of the vehicle (100; 130) which includes the drive unit (111). It can also be integrated into this basic assembly.

[0042] The handling device (121) has a workpiece holder (122). This is, for example, a straight groove into which a workpiece (211; 212) can be inserted. The individual workpiece (211; 212) can be secured in the workpiece holder (122), for example, by means of two gripping elements (123).

[0043] The handling device (121) has a housing (124) in which, for example, two gripper slides (125) are mounted so as to be displaceable relative to each other. Each gripper slide (125) carries a gripping element (123). The gripper slides (125) are driven by a common gripper drive motor (126). This motor is operated, for example, with the load voltage. The gripper drive motor (126) can also be operated with the control voltage potential. A displacement measuring system (127), for example, is arranged on the gripper slides (125) and on the housing (124) as a gripping force-related sensor (127). The output signal of this displacement measuring system (127) is, for example, an analog signal proportional to the gripping force, for example, in the range between 4 and 20 milliamperes. Instead of or in addition to the displacement measuring system (127), a force sensor can, for example, be used on the gripping elements (123). This can be a deformation sensor in the form of a strain gauge.A bridge circuit can be used to generate an output signal that is proportional to, for example, the gripping force.

[0044] The device housing (124) contains a controller (181) and a gripper sequence program memory (182). These are connected to the control voltage circuit. Each gripper sequence program stored in the gripper sequence program memory (182) contains all the parameters required to control and regulate a gripping task specific to the workpiece. The gripper sequence program is started from the control module (150) by inputting or transmitting a program identification, e.g., a program number, and a start signal.

[0045] The program sequence and the successful completion of the gripper sequence program are checked by means of a setpoint-actual comparison in the controller (181) of the handling device (121). Upon successful completion of the gripper sequence program or in the event of a fault, the controller (181) outputs a binary digital signal in a fourth transmission direction (194). In the handling device (121), the controller (181) and the position measuring system (127) are parts of a control loop (188). The controlled system (189) consists of the gripper carriages (125).

[0046] The device housing (124) has, for example, a removable cover (128). This cover is located, for example, on the outside of the handling device (121). After removing the cover (128), the electrical components of the handling device (121) are accessible. The cover (128) can be made of a non-metallic material, e.g. . It may be made of plastic, glass, etc.

[0047] In the exemplary embodiment, the handling device (121) also includes an antenna (184), a modulator and demodulator (185), and a converter (186) as further electrical components. The antenna (184) is, for example, arranged in the device housing (124) below the cover (128). This antenna (184) is used for data exchange with the control module (150). Instead of a single antenna (184) used for both transmitting and receiving, two antennas can also be used. In this case, for example, one antenna is used for transmitting and the other for receiving data and / or signals.

[0048] The antenna (184) is connected to the modulator and demodulator (185) by means of a high-frequency cable (187). Signal transmission occurs in the third transmission direction (193). It is also conceivable to connect the handling device (121) to the antenna (172) of the drive unit (111), for example, by means of the high-frequency cable (187). During reception, a low-frequency signal is produced from the high-frequency signal received by the antenna (172; 184) using the demodulator. This takes place, for example, in the receiver branch of the transmitter-receiver (183) of the handling device (121). The signal is then fed, for example, to the converter (186). During transmission, a high-frequency carrier signal is modulated in the modulator and demodulator (185) using the transmission signal output by the converter (186). This takes place, for example, in the transmitter branch of the transceiver (183). The modulated signal is then radiated by means of the antenna (172; 184).

[0049] The converter (186) is constructed, for example, in the same way as the converter (153) described in connection with the control module (150). Using the converter (186), a data packet transmitted in the aforementioned protocol format is converted into digital data, which is then processed by the controller (181) and the gripper sequence program memory (182). With a signal propagation direction in the fourth transmission direction (194), the signals output by the controller (181) are converted into a data protocol format by means of the converter (186). When transmitting binary signals between the control module (150) and the handling device (121), the converter (186) can optionally be omitted in both the receiving and transmitting branches.

[0050] The handling device (121) can have a separate transmitter instead of the described transceiver (183). For example, the receiving branch and the transmitting branch can then have their own antennas. The converters (186) for the transmitting branch and the receiving branch can also be arranged separately within the handling device (121). All these components are supplied, for example, by means of the control voltage.

[0051] In this embodiment, the control voltage (176) and load voltage (177) lines run between the drive unit (111) and the handling device (121). These lines, along with the ground potential, can be routed via a common connector. After disconnecting this connector, the handling device (121) can be detached from the rest of the workpiece carriage (100; 130).

[0052] A measuring station (17) is arranged on the rail support body (11). When the workpiece carriages (100; 130) loaded with a workpiece (211; 212) are moved, the length of a workpiece (211; 212) to be processed is determined, for example, by means of a light barrier and the position or speed signal of the workpiece carriages (100; 130). Workpiece release can also take place at the measuring station (17).

[0053] The individual machining robot (51; 71) stands on a base (52) on the hall floor. It carries a tool unit (53; 73) that can be swivelled and moved along multiple axes relative to the transport rail (82). The individual tool unit (53; 73) has several driven tools. These are, for example, milling, drilling, and sawing tools. The tool unit (53) of the first machining robot (51) can have different tools than the tool unit (73) of the second machining robot (71). The kinematics of the machining robots (51; 71) can also be configured differently.

[0054] In addition to the rail support body (11), the illustration shows the Figure 1A loading robot (221) is located on the hall floor. The loading robot (221) has a workpiece gripping device (222). This device is designed to swivel and move relative to the transport rail (82). The workpiece gripping device (221) can grip the workpiece (211; 212) to be processed pneumatically and / or mechanically. For example, before or during gripping, two reference edges of the workpiece (211; 212) are determined. This can be done optically and / or by means of a mechanical system.

[0055] The one in Figure 1The illustrated manufacturing cell (10) also has a workpiece removal device (231). In the exemplary embodiment, this includes a removal robot (231). The removal robot (231) is similar in design to the loading robot (221). The workpieces (211; 212) processed in the manufacturing cell (10) are removed from the work area by means of the removal robot (231) and, for example, placed on a stack. To grip the workpiece (211; 212), the removal robot (231) has, for example, a gripping device (232), such as a two-jaw parallel gripper. This gripper has, for example, two steel jaws with plastic inserts, each with a stroke of 13 millimeters. The closing force is, for example, 1920 Newtons.

[0056] The workpieces (211; 212) can be conveyed to the receiving area of ​​the loading robot (221) as stacks, individually incrementally, or in small batches. This allows the coupling of the production cell (10) with the preceding production stations in the material flow to be influenced. The production cell (10) can also be connected to a preceding production station by means of tracks. The workpieces (211; 212) can then, for example, already be conveyed to the production cell (10) on workpiece trolleys (100; 130).

[0057] Before the workpiece (211; 212) is inserted, two workpiece carriages (100, 130) are positioned, for example, offset from each other in the longitudinal direction (15) in a predetermined position in the insertion area (31). The handling devices (121) are each open. The standstill of the tool carriages (100, 130) in the insertion area (31) is transmitted wirelessly from the drive unit (111) to the control module (150) as a data protocol. After demodulation and conversion, the data protocol is available to the processing unit of the control module (150) as a digital data record for each individual workpiece carriage (100; 130). The open state of the handling devices (121) is transmitted wirelessly to the control module (150) as a binary signal. From the data of the drive units (111) and the signals of the handling devices (121), the control module (150) determines, for example, a binary enable signal, which is transmitted to the programmable logic controller (141).

[0058] The programmable logic controller (PLC) (141) controls the loading robot (221), which inserts the workpiece (211; 212) into the handling devices (121). As soon as the workpiece (211; 212) is in the intended position between the gripping elements (123), the PLC (141) sends a release signal to the control module (150). The control module (150) transmits, for example, a handling device-specific signal, a gripping item-specific signal, and a start signal as binary signals via its antenna (164). Simultaneously, the control module (150) blocks the movement of the two associated workpiece carriages (100, 130) along the transport track (82).

[0059] In the handling devices (121) mentioned above, the intended gripper sequence program specific to the workpiece is started. The gripper drive motor (126) moves the gripper slides (125) so that they engage the workpiece (211; 212) and clamp it. As soon as the signal value transmitted by the gripping force sensor (127) to the controller (181) is within a predefined tolerance range, the handling device (121) sends an end signal of the gripper sequence program to the control module (150).

[0060] The control module (150) locks the two handling devices (121) and controls the two workpiece carriages (100, 130) carrying the workpiece (211; 212). The two workpiece carriages (100, 130) are moved, for example, using a common travel profile, so that they always maintain the same distance from each other. This can be supported, if necessary, by the distance sensor (136). In this case, for example, the carriage (100; 130) at the front in the conveying direction is the master carriage and the other carriage (130; 100) the slave carriage. The travel profile transmitted to the drive units (111) of the workpiece carriages (100, 130) includes, for example, values ​​for acceleration, speed, and travel distance. During movement, there is a regular exchange of data between the control module (150) and the workpiece carriages (100; 130). The driving profile of the workpiece carriages (100; 130) is thus controlled in real time in a closed control loop.

[0061] The workpiece (211; 212) is conveyed by the workpiece carriages (100, 130) to the measuring station (17) downstream of the feeding point in the material flow. Here, in addition to the length measurement described above, a height and / or thickness measurement of the workpiece (211; 212) can also be carried out.

[0062] As soon as the first processing station (40) downstream of the measuring station (17) in the material flow is free, the first workpiece (211) is moved into the working area of ​​the first processing robot (51) by means of the workpiece carriages (100, 130). The workpiece carriages (100, 130) coming to a standstill in the designated position enables the subsequent functions of the manufacturing cell (10). The control module (150) sends a corresponding release signal to the higher-level control system (141). The support device (41) is moved to position itself against the first workpiece (211) and fixed to it. The support device (41) now supports the first workpiece (211) during the subsequent processing at the first processing station (40).

[0063] To machine this first workpiece (211), the first machining robot (51) swivels and / or moves the tool-equipped tool unit (53) to the first workpiece (211). If through-holes are provided in the workpiece (211), the suction cups of the support device (41) behind them can be retracted. After completion of the machining of the first workpiece (211) at the first machining station (40), the tool unit (53) and the support device (41) are returned to their respective starting positions. For example, the first support device (41) is moved back to its ready position. The workpiece carriages (100, 130) move the workpiece (211) to the second machining station (60).

[0064] The machining of the first workpiece (211) at the second machining station (60) is carried out analogously to the machining of this workpiece (211) at the first machining station (40). At this second machining station (60), for example, further recesses are made into the first workpiece (211), fittings are attached, etc. The execution time of the operations at the second machining station (60) largely corresponds to the execution time of the operations on this workpiece (211) at the first machining station (40). The execution time at each individual machining station (40; 60) is defined here as the time interval between the start of the first tool insertion of the machining robot (51; 71) and the completion of the last tool insertion of this machining robot (51; 71) on the individual workpiece (211; 212).

[0065] While the first workpiece (211) is being processed at the first processing station (40), a second workpiece (212) is provided in the insertion area (31), for example by means of the loading robot (221). As soon as the first workpiece (211) is moved from the first processing station (40) to the second processing station (60), which is coupled to it, for example without buffers, the second workpiece (212) is released for processing and conveyed to the first processing station (40).

[0066] The machining of the second workpiece (212) at the first machining station (40) is carried out analogously to the machining of the first workpiece (211) at this machining station (40). The operations and tools used for the two workpieces (211; 212) may differ. For example, the execution time of the operations performed on the second workpiece (212) at the first machining station (40) is at least approximately equal to the execution time of the operations performed on the first workpiece (211) at the second machining station (60). "At least approximately" here means that the execution times differ by a maximum of 10%.

[0067] After the first workpiece (211) has been machined at the second machining station (60), it is conveyed to the unloading area (201) by the workpiece carriages (100, 130). The second workpiece (212) is conveyed to the second machining station (60). The machining of the second workpiece (212) at the second machining station (60) is carried out as described above. The tools of the second tool unit (73) used for machining the second workpiece (212) may differ from those of the same tool unit (73) used for the first workpiece (211). For example, the machining time of the second machining station (60) for machining the second workpiece (212) is at least approximately the same as the machining time used for the first workpiece (211).

[0068] It is also conceivable to provide different processing times at the individual processing stations (40; 60). For example, the first processing station (40) or the second processing station (60) could alternately have a longer processing time than the other processing station (60; 40). The output rate can be slightly modified compared to the embodiment described above. The range of variation in the output rate is increased.

[0069] The individual workpiece (211; 212) can also be completely machined at one of the machining stations (40; 60). In this case, two workpieces (211; 212) are provided at each station. The processing time for the individual workpiece (211; 212) is, for example, the same at both machining stations (40, 60). The output rate in this case corresponds to the output rate described in connection with the first embodiment.

[0070] After processing is complete, the individual workpiece (211; 212) is conveyed to the unloading area (201) by the workpiece carriages (100, 130). The workpiece carriages (100, 130) stop at a predetermined position. In the control module (150), the drive units (111) of the workpiece carriages (100, 130) are locked and the handling devices (121) are activated. The unloading robot (231) grips the workpiece (211; 212) by means of the gripper (232), e.g., at the top edge. The control module (150) sends a start signal to both handling devices (121). The handling devices (121) open according to the intended gripper sequence program. The unloading robot (231) removes the workpiece (211; 212), swivels it, and places it, e.g., onto a transport cart, a conveyor belt, etc. The finished workpieces (211; 212) can be conveyed either individually or in batches.

[0071] After the workpiece (211; 212) has been removed and the release switch has been activated, the empty workpiece carriages (100, 130) continue from the removal area (201) along the transport rail (82). Their distance from each other may be smaller than during the process with the workpiece (211; 212).

[0072] They arrive, for example, individually at a first turntable (13). Here they are stopped. The turntable (13) pivots 180 degrees so that the individual workpiece carriage (100, 130) can move onto the rear return rail (83). For example, the workpiece carriage (100, 130) and / or the handling device (121) can now be addressed by means of a second transmitter of the control module (150). In this case, the receiving frequency of the respective receiver adjusts itself, for example, to the stronger transmit signal of the control module (150).

[0073] The same process is carried out for the subsequent workpiece carriages (130; 100). The workpiece carriages (100, 130) now move along the return rail (83) to the second rotary table (14), which is located near the insertion area (31). Here, the workpiece carriages (100, 130) are redirected back onto the transport rail (82). In the insertion area (31), they can then be loaded with new workpieces (211; 212) to be processed. For example, up to 18 workpiece carriages (100, 130) are in circulation in the production cell (10). Reference symbol list:

[0074] 10 Production cell 11 Rail support body 12 Guide grid 13 Turntable 14 Turntable 15 Longitudinal direction 16 Transverse direction 17 Measuring station 19 Rack 21 electrical conductors 22 electrical conductors 23 electrical conductors 24 electrical conductors 25 electrical conductors 31 Application area 40th processing station 41st support device 51 Machining robot 52 Base 53 Tool unit 60 Second machining device 61 Second support device 71 Machining robot 73 Tool unit 80 Conveyor system 81 Workpiece transport device 82 Transport track, transport rail 83 Return track, return rail 100 vehicles, workpiece trolleys, 101 ball recirculating shoes 103 Sliding contacts 104 Sliding contact 105 Sliding contact 106 Sliding contact 107 Sliding contact 108 Parallelogram guide 109 Housing 111 Drive unit 112 Cover 113 Flange support 114 Drive motor 115 Drive wheel 116 Lubrication wheel 117 Speed-related sensor, rotary encoder 121 Handling device 122 Workpiece holder 123 Gripping element 124 Device housing 125 Gripper slide 126 Gripper drive motor 127 Gripping force sensor, gripping force sensor, displacement measuring system 128 Cover 130 Vehicles, workpiece trolleys 135 Direction of travel 136 Distance sensor 140 control cabinet 150 Control module 151 Program memory 152 Controller 153 Converter 154 Transceiver 155 Data line to higher-level controller 156 First controller input 157 Second controller input, setpoint input 158 ​​Third controller input, measured value input 159 Controller output 161Control system 162Data line 163Modulator-demodulator 164Antenna 170 Control module 171 Transceiver 172 Antenna 173 Demodulator-modulator 174 Converter 176 Control voltage 177 Load voltage 181 Controller 182 Gripper sequence program memory 183 Transceiver 184 Antenna 185 Modulator and demodulator 186 Converter 187 High-frequency cable 188 Control loop 189 Controlled system 191 first transmission direction, transmission direction 192 second transmission direction, transmission direction 193 third transmission direction 194 fourth transmission direction 201 Extraction area 211Workpiece 212Workpiece 221 Loading robot 222 Workpiece gripping device 231 Workpiece removal device, removal robot 232 Gripping device m / s Unit of measurement for speed [meters per second] N Unit of measurement for force [Newton] M Symbol for motor

Claims

1. A conveying system (80) of a production cell (10) having a stationary control module (150) and at least one track- or line-bound, self-driving vehicle (100; 130), - wherein the control module (150) has at least one antenna (164) for the bidirectional wireless transmission of data and signals between the vehicle (100; 130) and the control module (150), - wherein the vehicle (100; 130) has at least one antenna (172), which is assigned to a drive unit (111) of the vehicle (100; 130), - wherein the drive unit (111) has a converter (174) for converting a data set transferred in a protocol format by the control module (150) into digital actuation signals of a drive motor (114) of the drive unit (111), characterised - in that the drive unit (111) has a speed-related sensor (117), wherein the drive unit (111) is designed to transmit the output signal of this speed-related sensor (117) in a protocol format to the control module (150) so that the control module (150) controls a driving profile of the vehicle (100; 130) in real time in a closed loop.

2. The conveying system (80) according to Claim 1, characterised - in that the vehicle (100, 130) bears at least one handling device (121), - in that the handling device (121) is assigned at least one second antenna (184) of the vehicle (100; 130), or the handling device (121) is connected to the antenna (172) assigned to the drive unit (111), - in that the handling device (121) has a control unit (181) and a gripper sequence program memory (182) so that a binary signal of the control module (150) starts a gripper sequence program, - in that the handling device (121) has a gripping-force-related sensor (127), the data of which are transmitted to the control unit (181) of the handling device (121), and - in that the handling device (121) outputs a binary signal to the control module (150) after the gripper sequence program is completed.

3. The conveying system (80) according to Claim 2, characterised - in that the control module (150) has at least one transmitter and at least one receiver or at least one transceiver (154), and - in that each drive unit (111) and each handling device (121) has a transmitter and a receiver or a transceiver (171, 183) for communication with the control module (150).

4. The conveying system (80) according to Claim 2, characterised in that the wireless connection of the control module (150) to the drive unit (111) and to the handling device (121) of the vehicle (100; 130) is in each case a point-to-point connection.

5. The conveying system (80) according to Claim 1, characterised in that the control module (150) has a converter (153), which is connected upstream of a modulator of the transmitter or of the transmitter branch of the transceiver (154), for transmitting the transferred data in a data protocol.

6. The conveying system (80) according to Claim 1, characterised in that the drive unit (111) and the handling device (121) are mutually locked in the control module (150) so that the control module (150) alternatively actuates either the drive unit (111) or the handling device (121).

7. The conveying system (80) according to Claim 1, characterised in that the data cable (162) between the receiver or the receiver branch of the transceiver (154; 171; 183) and the converter (153; 174; 186), and / or the data cable between the converter (153; 174; 186) and the transmitter or the transmitter branch of the transceiver (154; 171; 183) is an unshielded cable.

8. The conveying system (80) according to Claim 1, characterised in that the individual vehicle (100; 130) has at least one distance sensor (136), which is oriented in a direction of travel (135).

9. The conveying system (80) according to Claim 1, characterised in that the control module (150) is assigned at least two vehicles (100, 130), which each have at least one handling device (121).

10. A production cell (10) having a programmable logic controller (141) and having a conveying system (80) according to Claim 1, characterised in that the control module (150) is connected to the programmable logic controller (141).