CONVEYOR SYSTEM AND METHOD FOR CONTROLLING SUCH A CONVEYOR SYSTEM

Abstract

A conveyor system has a conveyor section, at least one first moving trolley which carries along a dedicated drive and is movable with the latter along the conveyor section and which has a first trolley parameter, and a controller which, taking into consideration the first trolley parameter triggers various actions with the aid of waypoints along the conveyor section. For more flexible use of the conveyor system, at least one second moving trolley having a second trolley parameter differing from the first trolley parameter is provided, and the controller is designed to place at least one waypoint along the conveyor section, at which waypoint a certain action is triggered, for the second moving trolley at a different position along the conveyor section than for the first moving trolley.

Claims

1. A conveyor system comprising: a) a conveyor section, b) at least one first moving trolley which carries along a dedicated drive and is movable with the latter along the conveyor section and which has a first trolley parameter, and c) a controller which, taking into consideration the first trolley parameter, triggers various actions with the aid of waypoints along the conveyor section, wherein d) at least one second moving trolley having a second trolley parameter differing from the first trolley parameter is provided, and e) the controller is designed to place at least one waypoint along the conveyor section, at which waypoint a certain action is triggered, for the second moving trolley at a different position along the conveyor section than for the first moving trolley.

2. The conveyor system as claimed in claim 1, wherein the first and second trolley parameter is a trolley length, a mass, a maximum acceleration, a speed and/or a functional length of the moving trolleys.

3. The conveyor system as claimed in claim 1, wherein the second trolley parameter -of the second moving trolley differs from the first trolley parameter of the first moving trolley due to a coupling of two moving trolleys.

4. The conveyor system as claimed in claim 1, wherein one of the two coupled moving trolleys is a moving trolley which has broken down due to a technical fault.

5. The conveyor system as claimed in claim 1, wherein one of the two coupled moving trolleys is a towing trolley.

6. The conveyor system as claimed in one claim 1, wherein the controller is designed such that the specific action which is carried out at the waypoint also takes into consideration the difference of the second trolley parameter from the first trolley parameter.

7. The conveyor system as claimed in claim 1, wherein the two moving trolleys carry a moving trolley controller with a waypoint storage device and a device for detecting the actual position along the conveyor section and the second moving trolley stores in the waypoint storage device a different waypoint for the specific action.

8. The conveyor system as claimed in claim 1, wherein the displaced waypoint leads to the application of emergency travel parameters on the second moving trolley.

9. A method for controlling a conveyor system comprising a conveyor section, at least one first moving trolley which carries along a dedicated drive and is movable with the latter along the conveyor section and which has a first trolley parameter, and a controller which, taking into consideration the first trolley parameter, triggers various actions with the aid of waypoints along the conveyor section, wherein the method comprises the following steps: providing at least one second moving trolley having a second trolley parameter differing from the first trolley parameter; placing at least one waypoint along the conveyor section, at which waypoint a certain action is triggered, for the second moving trolley at a different position along the conveyor section than for the first moving trolley.

10. The method as claimed in claim 9, further comprising the following steps: coupling a different moving trolley for towing a moving trolley which has broken down due to a technical fault, whereby the second moving trolley is produced; and moving the second moving trolley, by taking into consideration the displaced waypoint.

11. The method as claimed in claim 10, wherein the different moving trolley is coupled to the moving trolley in a portion of the conveyor section which is difficult to access for operating personnel

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0065] Exemplary embodiments of the invention are described in more detail hereinafter with reference to the drawings. In which:

[0066] FIG. 1 shows a schematic view of a conveyor system having a conveyor section which comprises different portions and branches;

[0067] FIG. 2 shows a side view of a portion of the conveyor section in which a plurality of conveyor trolleys are shown at their normal operating distance;

[0068] FIG. 3 shows a side view according to FIG. 2, wherein two of the conveyor trolleys are shown coupled together, however;

[0069] FIG. 4 shows a side view of the conveyor section in the region upstream of a track switch, with a conveyor trolley which moves toward two waypoints for controlling its drive;

[0070] FIG. 5 shows a side view according to FIG. 4, wherein the conveyor trolley is located on the first of the two waypoints;

[0071] FIG. 6 shows a side view according to FIG. 4, wherein the conveyor trolley is located on the second of the two waypoints;

[0072] FIG. 7 shows a side view according to FIG. 4, wherein two coupled conveyor trolleys move toward two waypoints which in comparison with the two waypoints of FIGS. 4 to 6 are positioned further upstream of the track switch;

[0073] FIG. 8 shows a side view according to FIG. 7, wherein the coupled conveyor trolleys are located at the first of the two waypoints shifted forward;

[0074] FIG. 9 shows a side view according to FIG. 7, wherein the coupled conveyor trolleys are located at the second of the two waypoints shifted forward;

[0075] FIG. 10 shows a side view according to FIG. 7, wherein a conveyor trolley is shown to which a towing trolley approaches;

[0076] FIG. 11 shows a side view according to FIG. 10, wherein the towing trolley has been coupled onto the conveyor trolley;

[0077] FIG. 12 shows a side view according to FIG. 10, wherein the towing trolley is located at the second waypoint which in this case has been shifted downstream.

DESCRIPTION OF PREFERRED EXEMPLARY EMBODIMENTS

[0078] In FIG. 1 a conveyor system, denoted as a whole by the reference numeral 10, is shown with a conveyor section 12 and a plurality of conveyor trolleys 14 at different positions along the conveyor section 12.

[0079] The conveyor section 12 comprises different section portions which in the plan view approximately show two circuits nested in one another, between which the conveyor trolleys 14 and the workpieces conveyed thereby, here by way of example vehicle bodies 15, may alternate to and fro by means of a plurality of track switches 16 as track alteration devices.

[0080] In order to illustrate where the invention is particularly useful, FIG. 1 shows in the center a section portion of the conveyor section 12 which represents an area which is difficult to access for operating personnel, which here by way of example is intended to be a painting booth 18. Thus as becomes clear below by means of the further figures, inside the painting booth 18 the conveyor trolleys 14 are guided below a partition floor and the vehicle bodies 15 are guided above the partition floor.

[0081] Via the two track switches 16 upstream and downstream of the painting booth 18 the conveyor trolleys 14, in which the conveyed vehicle bodies 15 are not intended to be painted, are guided on a bypass section 20 which runs parallel to the painting booth 18.

[0082] In the lower region of FIG. 1, a servicing section 22 of the conveyor section branching off from the main section is identifiable, conveyor trolleys 14 generally without a conveyed vehicle body 15 being able to be serviced and/or parked therein.

[0083] An idling buffer 24, in which conveyor trolleys 14 including the vehicle bodies 15 may be buffered, is shown by way of example in the upper region of FIG. 1.

[0084] Moreover, along the conveyor section 12 (top right in FIG. 1), a transfer unit 26 is also shown, the conveyor trolleys 14 being able to be relocated thereby onto a different transport plane, for example for further assembly of the motor vehicle. The transfer unit 26 is also a section portion of the conveyor section 12 which is difficult to access for operating personnel.

[0085] Finally, the conveyor section 12 comprises links 28 to further conveyor systems of an entire higher-order production plant.

[0086] A system controller 30, which here by way of example may communicate via a wireless communication link 32 with the conveyor trolleys 14, is provided for controlling the conveyor system 10. Alternatively or additionally, primarily in a rail-guided conveyor system 10 as shown here, communicating sliding conductor lines may be used along the conveyor section 12 for communicating with the conveyor trolleys 14.

[0087] Moreover, the system controller 30 is also connected via a communication link 34 to the manufacturing systems, in this case the painting booth 18 and/or the working components thereof such as the painting robots. Typically, the manufacturing systems have individual controllers dedicated thereto which only receive higher-order commands from the system controller 30 and internally control the appropriate movement, for example, of the painting robots.

[0088] Finally, the system controller 30 is connected via a communication link 36 to the conveyor section 12, i.e. in particular to the track switches 16 arranged along the conveyor section 12 and/or other actuators and sensors influencing the track.

[0089] In FIGS. 2 and 3 a section portion of the conveyor section 12 in the painting booth 18 is shown in a sectional view.

[0090] In this case only one partition floor 38 of the painting booth is shown, said partition floor dividing a travel space of the booth, in which the conveyor trolleys 14 move and in which the vehicle bodies 15 are guided. To this end the partition floor 38 has a longitudinal gap through which supporting rods 39 of the conveyor trolleys 14 protrude.

[0091] Initially it may be identified that the conveyor section 12 is predetermined by a rail 40, along which a conveyor trolley 14 with the conveyed vehicle body 15 is moved. To this end, the conveyor trolley 14 has a chassis 42 which has a dedicated drive 44 by which the conveyor trolley may move by its own power along the rail 42. For controlling the drive 44 the conveyor trolley 14 also carries a moving trolley controller 46 which reads by means of a reader device 48, for example, barcodes or other markings attached to the rail 42, in order to determine the position of the conveyor trolley along the route 12. For details of an exemplary barcode positioning system, reference should be made to DE 10 2012 010 677 A1.

[0092] Moreover, the trolley 14 has a separating device 50 by which the non-positive connection between the drive motor 44 and the conveyor section 12 may be disconnected, by actuating elements 52, 54 being actuated on the front and/or rear end of the conveyor trolley. Typically, the power flow is interrupted at a transmission of the drive. For details of the design of the separating device 50, reference should be made to the hitherto still unpublished DE 10 2018 109 584 of the applicant.

[0093] As shown in FIG. 3, the separating device 50 may be used to tow a broken-down conveyor trolley 14′ with a further conveyor trolley 14.

[0094] To this end, as visible in FIG. 3, the trailing conveyor trolley 14 travels toward the broken-down conveyor trolley 14′, whereby the separating device 50 is actuated. Additionally, a coupling of the two trolleys may be carried out. The drive 44 of the broken-down conveyor trolley 14′ is now virtually idling so that the trailing conveyor trolley 14 forms with the broken-down conveyor trolley 14′ a coupled vehicle combination.

[0095] Frequently, a conveyor trolley 14′ remains stationary since an electrical component malfunctions. Thus it may be advantageous if an electrical bypass contact is produced at the same time as the coupling, by which the towing conveyor trolley 14, for example, may perform a diagnosis or may use still functioning sensors, such as for example a front distance sensor of the damaged conveyor trolley 14′.

[0096] The controller 30 may identify a broken-down conveyor trolley 14′, for example by a distance sensor system on the trailing conveyor trolley 14 identifying a safety distance being dropped below, and communicating this to the controller 30. Moreover, sensor systems along the conveyor section 12 may report that an anticipated conveyor trolley 14 has not reached a sensor position within a predetermined time. The controller 30 may then issue the command to move toward the broken-down conveyor trolley 14.

[0097] After being successfully coupled-on, the controller 30 establishes where the broken-down conveyor trolley 14′ has to be moved to and prepares the corresponding track alteration devices. The controller 30 may also inform the remaining process controller about the loss of the two conveyor trolleys.

[0098] By the coupling of the two conveyor trolleys 14 and 14′ the trolley parameter which is relevant for the movement of the still functioning conveyor trolley 14 is changed. For example, a trolley parameter is its functional length in normal operation BL (see FIG. 2) which increases by the coupling to a functional length in emergency operation NL (see FIG. 3).

[0099] As described hereinafter the trolley parameters play an important role in the control of the conveyor system 10.

[0100] FIGS. 4 and 6 show a portion of the conveyor section 12 upstream of a track switch 16.

[0101] For controlling the conveyor system 10 the system controller 30 of the moving trolley controller 46 predetermines waypoints in which specific actions are carried out when reached. These waypoints are virtual waypoints which are defined in the system controller 30 and during the design of the conveyor system 10 are fixed when designing the conveyor section 12.

[0102] Thus in FIGS. 4 to 6, a braking waypoint 60 is arranged upstream of the track switch 16 with a predetermined operating braking distance BBA, and slightly downstream along the conveyor section a stop waypoint 62 is arranged at the operating stopping distance BSA. All of the waypoints, i.e. also the braking waypoint and the stop waypoint 62, are adapted in each case to the functional length in normal operation BL of the conveyor trolleys 14.

[0103] In FIG. 5 the conveyor trolley 14 has reached the braking waypoint 60 which is identified by the reader device 48 of the moving trolley controller 46. Due to a previous prediction on the part of the system controller 30, the moving trolley controller 46 at this position reduces the travel speed of the conveyor trolley 14.

[0104] In FIG. 6 the conveyor trolley 14, traveling more slowly, has reached the stop waypoint 62 which is identified in turn by the reader device 48. In this position the conveyor trolley 14 stops and waits until the track switch 16 provides the correct track.

[0105] Since the functional length BL and the placing of the braking waypoint 60 and the stop waypoint 62 are taken into consideration when designing the conveyor system 10, the conveyor trolley 14 comes to a halt such that its front end does not protrude into the track switch 16.

[0106] In FIGS. 7 to 9, the same portion of the conveyor section 12 upstream of a track switch 16 is shown. However, here a coupled vehicle combination consisting of a conveyor trolley 14 and a broken-down conveyor trolley 14′ moves toward the track switch 16.

[0107] For this emergency travel situation the controller 30 has transferred other waypoints to the moving trolley controller 46 of the towing conveyor trolley 14 (see FIG. 7). Due to the increased functional length in emergency operation NL, an emergency braking waypoint 66 has been displaced upstream of an emergency braking distance NBA. An emergency stop waypoint 68 has also been displaced upstream.

[0108] In this manner, the vehicle combination consisting of the two conveyor trolleys 14 and 14′, as visible in FIG. 9, also optimally comes to a standstill upstream of the track switch 16 in spite of its greater functional length NL.

[0109] The braking waypoint 60 and the stop waypoint 62 once again apply to the conveyor trolley 14 following the vehicle combination, so that effectively the waypoints have been only temporarily displaced.

[0110] In FIGS. 10 to 12 the portion of the conveyor section 12 upstream of the track switch 16 is shown once again.

[0111] However, here a specially designed towing trolley 14″ is used. This is clearly of shorter construction than the conveyor trolley 14 and is not provided for conveying workpieces. Additionally the towing trolley 14″ may be designed as a mobile emergency device which may be used by operating personnel on any point of the track. Should the towing trolley 14″ lack the required weight in order to transmit a sufficient drive force, spring-loaded contact rollers may be provided for the drive 44.

[0112] In FIG. 10 the towing trolley 14″, coming from the right, moves toward the broken-down conveyor trolley 14′. In this case, for the towing procedure, the conveyor trolley 14 is not pushed but pulled.

[0113] In the coupled-on state the vehicle combination consisting of the broken-down conveyor trolley 14′ and the towing trolley 14″ has an only slightly extended functional length in emergency operation NL, relative to the functional length in normal operation BL.

[0114] As visible in FIGS. 11 and 12, the controller 30 displaces the emergency braking waypoint 66 to an emergency braking distance NBA downstream relative to the original position, since now the reader device 48 in the vehicle combination is located further forward than on a normal conveyor trolley 14. Similarly, the emergency stop waypoint 68 has been displaced downstream. Since the towing trolley 14″ is also able to generate less braking acceleration, as a further differing trolley parameter compared to a conveyor trolley 14, the emergency braking distance NBA is located relatively further upstream of the emergency stop waypoint 68.