Abstract:
A process module for a processing station ( 18 ) for performing a predetermined function. The module comprises a controller ( 60 ) associated with a program control unit ( 76; 76 ′) to which a program for controlling the process module is supplied. The controller ( 60 ) comprises a program data administrator unit ( 74 ) which co-ordinates the transfer of the program associated with the process module ( 30 ) out of a program data memory ( 72, 72′, 72″ ) into the program control unit ( 76, 76′ ). The invention also relates to a processing station with at least one such process module ( 30 ) for performing a predetermined function, as well as a method for starting up such a processing station.

Description:
BACKGROUND 
   The present invention relates to a process module for a processing station for performing a predetermined function, comprising a controller associated with a program control unit which runs a program for controlling the process module. The invention also relates to a processing station with at least one such process module and a bus system for transmitting data to the controller of the process module. The invention also relates to a method for starting up such a processing station. 
   A processing station of the mentioned type is disclosed for example in the German patent application DE 197 41 671 A1. Such processing stations are normally part of a modular processing, assembly and testing system for the processing, assembly and testing of products. Each processing station within the assembly system has at least one given function to be carried out on the product. For example, the function can be the connection of two parts of a housing. Another function may be the marking of a housing part with a laser. These functions are automatically performed in the processing stations. In addition, an assembly system also comprises for example manual processing stations, where the functions are manually performed, as well as pure transfer stations which only convey pallets carrying the products. 
   Processing stations are shown in the above-mentioned document having several so-called process modules. These process modules are each separate devices for carrying out a separate function. Since a processing station can have several such process modules, it is possible for the processing station to carry out several functions. 
   Due to the modular construction, the process modules can be built into and removed from the processing station with little effort. Apart from plugging in the necessary connections for supply media, such as compressed air, electricity, etc., it is necessary for starting up the module to read in the program (software module) for controlling the function into a central basis controller of the processing station, where it is then run together with the other programs for the other process modules. The basis controller for example is a so-called SPS. The program is read in through a notebook, which is connected to the basis controller. 
   Although this procedure is fast and simple in practice, the need still exists for further simplifying the installation of process modules. In particular, the installation should be so simple that it can be readily carried out even by unskilled personnel, i.e. it should have a so-called “plug and work” functionality. 
   The German patent application DE 199 06 341 A1 discloses a method for loading a program in peripheral computers for peripheral devices in the printing industry. The German patent DE 195 06 957 C2 discloses a method for updating and loading application programs in a memory of a microprocessor system. The German patent application DE 196 24 929 A1 discloses a process automation system and the German patent application DE 196 15 190 A1 discloses a network based controller for industrial plants. 
   In view of the above, the object of the invention is to improve the process module of the mentioned type such that it can be rapidly and simply installed also by unskilled personnel. A further object of the invention is to simplify testing and servicing tasks. 
   SUMMARY OF THE INVENTION 
   The mentioned objects are achieved with the process module of the mentioned type in that the controller comprises a program data administrator unit, which co-ordinates the transfer of the program associated with the process module out of a program data memory into the program control unit. The advantage achieved is that the program necessary for controlling the process module (control program) no longer needs to be read in manually by the operating personnel, but this procedure is automatically carried out after connecting the process module to the processing station. Thus, the process module has enough “intelligence” that it can directly transmit the program to the program control unit for running the program or at least can transmit information as to where the program is located. 
   The possibility of automatically transferring the program necessary for control of the process module leads to a distinct simplification of the structure of the processing station, so that not only time, but money can be saved, which was previously required for a technician for start-up. 
   As already mentioned, the transmission of the program is coordinated by the program data administrator unit. The term “co-ordination” in this respect is to be understood in the simplest case in that the program data administrator unit contains the information which is necessary for example for the basis controller to find the memory location of the program and to then transfer the program out of the memory into the program control unit. The program data administrator unit in this case plays a passive role. In the broadest sense, the term “co-ordination” however is to be understood in that the program data administrator unit actively removes the desired program from the program data memory and transfers it to the program control unit. It will be understood that intermediate solutions are also possible. The control program thus can be loaded from different sources, for example from a memory in the process module, from the Internet, from a disk, CD-ROM, etc. 
   In a preferred embodiment, the controller of the process module comprises the program data memory. The feature has the advantage that the process module includes all software and hardware components which in the end are necessary for startup and operation of the process module. It is also very simple to test this process module, also outside of the processing station. The person carrying out the tests need not be concerned for example whether the program used in the tests corresponds to the program used or to be used in the processing station. Rather, access is made to the program stored in the program data memory, which is used in normal operation. 
   In a preferred embodiment, the controller of the process module comprises the program control unit, preferably configured as a microprocessor. In other words, this means that the controller within the process module comprises a microcomputer upon which the program runs. The feature has the advantage that functions for which time is critical can be carried out, because the program is no longer run in a central basis controller associated with all process modules together with other programs for the other process modules in a processing station. 
   The duration between the completion of the program and a new start of the program (time cycle of the program) is distinctly reduced. In addition, the program control unit can be optimised with respect to the program to be run, which not only leads to an improvement in the control of the process module, but also to certain cost advantages. In particular, it is no longer necessary to design the basis controller to account for running the most complex and the most time critical program. In addition, an autark process module is realised. 
   In a preferred embodiment, the program data administrator unit comprises a memory for storing data specific to the process module. In addition, the program data administrator unit is preferably connectable through a bus to the program data memory. 
   The data specific to the process module stored in the memory is for example an identification number of the process module, which among other things depends on the function to be performed, or is data on the memory location of the program, for example the memory address within the process module memory, or is an Internet address from which the program can be uploaded. Further product specific information is for example the location of the program control unit necessary for running the program, for example the process module or the basis controller. 
   As already mentioned, these data are necessary when the program data administrator unit works passively. In this case, the basis controller calls up the data through the bus and carries out the corresponding actions. 
   Alternatively, the program data administrator unit can operate actively, so that the transmission of program data is carried out directly by the unit to the program control unit without operation of the basis controller. In the best case, the basis controller can even be completely relinquished. 
   The object underlying the invention is also achieved by a processing station of the mentioned type, characterised in that the controller of the process module comprises a program data administrator unit which co-ordinates the transmission of the program associated with the process module out of a program data memory into the program control unit. The advantages explained in conjunction with the process module are also present here. 
   In a preferred embodiment, the preferably provided basis controller of the processing station includes the program control unit. That is, the programs necessary for controlling functions of the individual process modules run centrally in the basis controller, where preferably several microprocessors are provided, so that the programs run in parallel, i.e. simultaneously, and interruptions do not result due to the duration of the program cycle. It is also contemplated that the programs be run in a time sharing mode, quasi parallel on one microprocessor. 
   Depending on the application, the processing station can be equipped with several process modules, preferably up to a maximum of four process modules, so that the processing station itself can carry out a number of functions corresponding to the number of process modules. 
   In a preferred embodiment, the basis controller and/or the controller of a process module are configured such that they can establish a connection to the program data memory, which is located outside of the processing station, for example in the memory of a central control system, in a databank of a computer or on an Internet server. 
   This feature has the advantage that the program can be loaded, for example over the Internet from a server connected to the Internet, so that especially the care of the program and the installation of updates is greatly simplified. It will be understood that other data networks can be used for this purpose instead of the Internet. 
   The object underlying the invention is also achieved by a method for starting up a processing station with the above-mentioned features, which is characterised in that after connection of a process module to the processing station, preferably through an interface, the program for controlling the process module, depending on data specific to the process module stored in the program data administrator unit, is read out from the program data memory and transmitted to the program control unit. Preferably, the data specific to the process module comprise at least one of the following data: memory location of the program, location of the transmission target of the program and identification data of the process module. The above-described advantages are also realised by this method. 
   Further advantages and embodiments of the invention result from the following description and the attached drawings. It will be understood that the above-mentioned features and those to be described below are applicable not only in the given combinations but may be used in other combinations or taken alone without departing from the scope of the present invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will now be described in more detail in terms of an embodiment with reference to the drawings. 
       FIG. 1  shows a schematic illustration in side and plan view of a complete processing station and a processing, testing and assembly facility. 
       FIG. 2  shows a schematic illustration of an automatic processing station with exchangeable process modules. 
       FIG. 3  shows a schematic illustration of the control structure of the processing facility. 
       FIG. 4A  shows a schematic block diagram of the control of a processing station. 
       FIG. 4B  shows a schematic block diagram of the control of a processing station of  FIG. 4A , without a basis controller. 
   

   DETAILED DESCRIPTION 
   An assembly system or processing facility is shown in  FIG. 1  with the numeral  10 . The processing facility  10  is shown in side view in the upper illustration and in plan view in the lower illustration. The processing facility  10  comprises several units  12 . 1  to  12 . 6  arranged in series. The number of six units is exemplary and this is not a limitation in practice. Rather, the processing facility can consist of more or fewer than six units, which need not be arranged in a line, but can be provided in other geometrical forms. 
   Each of the units  12 . 1  to  12 . 6  comprises two parallel conveyor sections, which are indicated with the numerals  14 ,  16  in the lower plan view. The two conveyor sections  14 ,  16  provided in the units  12 . 1  to  12 . 6  comprise counter directional transport devices. The conveyor sections  14 ,  16  of the units  12 . 1  to  12 . 6  are designed such that the transport of a pallet from one unit to the next unit is possible. To achieve a closed conveyor system, the two units  12 . 1  and  12 . 6  arranged at the ends of the processing facility are provided with deflection or turn-around units, which connect the two conveyor sections  14 ,  16  of the neighbouring unit  12 . 2  or  12 . 5  to one another. 
   Such a processing facility  10  makes it possible to subject a work piece circulating on a pallet to a series of different processing steps. For this purpose, the units  12 . 2  to  12 . 5  are configured differently, because they are to achieve different purposes. The unit  12 . 2  is configured as an automatic processing station  18 , the two units  12 . 3  and  12 . 4  as manual processing stations  20  and the unit  12 . 5  as a pure transfer station (buffer)  22 . 
   Energy supply trains extend from unit to unit for supplying the individual units  12 . 1  to  12 . 6  with the necessary media, for example electricity, compressed air, etc. In the side view of  FIG. 1 , the compressed air or pneumatic supply line is indicated with the numeral  24 , while the electrical supply train is indicated with the numeral  26 . The pneumatic line  24  runs in the lower region of the units  12 . 1  to  12 . 6 , while in contrast the electrical supply train  26  runs in the upper region of the units. The electrical supply train  26  contains not only lines for electric power supply, but also for example lines for a data bus. The connection of the two supply trains  24 ,  26  between the units is normally made with plug connectors, which are not shown in the figure for reasons of clarity. 
   The automatic processing station  18  provided in the processing facility  10  is capable of performing not only one function but several functions when needed. In this respect, a function will be understood as a working step performed on the work piece passing through the processing station. A working step for example can be a cutting or non-cutting processing of the work piece, the connection of the work piece with another part, the testing of the work piece for functionability, marking of the work piece with a laser or any other testing procedure or processing step. 
   Each of these functions or each of these working steps is referred to in the following as the process, where the automatic processing station  18  comprises a correspondingly designed process module for carrying out such processes. The process module is indicated in  FIG. 1  with the numeral  30 . As can be clearly seen in  FIG. 1 , the automatic processing station  18  comprises four such process modules  30 . This number of four however is only an example. A smaller number of process modules is possible or possibly also a larger number of process modules. 
   Each process module  30  is self-contained and is functionally independent of the other process modules  30  present in a processing station  18 . The installation of the electric and pneumatic lines of the process module  30  is prepared, so that it is only necessary to couple to the corresponding supply train, for example by means of normal plug connections. 
     FIG. 2  shows a process module in side view, which is supported on a platform  31 . The arrow  32  indicates that the process module  30  can be driven into the processing station  18  and connected there to a correspondingly provided carrier unit (not shown). The carrier unit comprises supporting elements which carry the process module  30 , as well as at least two positioning elements which provide for an exact positioning of the process module  30  within the processing station  18 . The connection of the process module  30  to the supply trains  24 ,  26  is accomplished with schematically indicated plug connectors  34 ,  36 . 
   This modular construction of the automatic processing station  18  allows a very flexible and simple adaptation to the requirements of the user of the processing facility  10 . In addition, an adaptation or change of the automatic processing station  18  is possible at any time by exchanging the respective process module  30  with a module having another function. 
   As mentioned above, the connection of the process module  30  to the supply trains  24 ,  26  takes place with corresponding plug connectors  34 ,  36 . To start up the process module  30 , it is also necessary to install and start software components (referred to as program in the following) for controlling the process module  30  at the corresponding location. This procedure will now be described in conjunction with  FIGS. 3 and 4 . 
     FIG. 3  schematically illustrates a section of the control structure of the processing facility  10 . The processing facility  10  optionally comprises a facility control or central control system  40 , which handles overreaching and coordinating functions within the entire processing facility  10 . This central control system contains among other things the configuration of the entire facility as well as the working sequence of the work pieces to be processed. The central control system  40  communicates with the individual units  12 . 1  to  12 . 6  through a data bus  42 , which for example is configured as a profibus. The individual units  12 . 1  to  12 . 6  are connected to the data bus  42  by a plug connector  44 , when necessary. As mentioned, the data bus  42  is part of the electric supply train  26 , which extends through the entire processing facility  10 . 
     FIG. 3  illustrates the control structure of the automatic processing station  18 , which is connected to the data bus  42  by the plug connector  44 . The processing station  18  comprises a basis or station controller  50  connected to an internal data bus  52 . This basis controller  50 , for example a SPS, has the purpose of carrying out the tasks assigned to the processing station  18 . This includes for example shutting off the entire station when actuating an emergency OFF switch, which is indicated in  FIG. 3  with the numeral  54 . A further task of the basis controller  50  can be the communication over the data bus with the central control system  40  and also with other previous or prior units  12  of the processing facility  10 . 
   The input and output of information, data or commands takes place through a station operating device  56 , which is also connected to the internal data bus  52 . This station operating device  56  comprises a display for indicating certain information, as well as a keyboard for inputting data. The station operating device  56  is ergonomically attached to an easily accessible location in the processing station  18 . The basis controller  50  in contrast is contained in a housing, normally electro-magnetically shielded, which is indicated in  FIG. 2  with the numeral  58 . As mentioned, the processing station  18  is configured to receive several processing modules  30 . To connect the process modules  30 , a number of the mentioned plug connectors  36  are provided in the same number as the modules. In the present embodiment, the processing station  18  can receive four process modules  30 , so that four plug connectors  36  are provided. For reasons of clarity, only the control structure for one process module  30  is shown in  FIG. 3 . 
   The process module  30  comprises a decentral input/output unit or controller  60  (process module controller), which is connected to the internal data bus  52 . This process module controller  60  has the task of controlling the devices provided with the process module  30 . Such devices include for example step motors, actuators, laser marking devices, measurement and testing devices, etc. A step motor  62  and two input/output interfaces  64  are illustrated in  FIG. 3  only as an example, where the latter can for example serve to control a laser and to receive measured data. 
   A program is necessary for process control of the mentioned devices in a process module  30 , which is contained either in the process module controller  60  or in the basis controller  50 . In the first case, the process module controller  60  has a corresponding program control unit  76 . If the program runs in the basis controller  50 , the corresponding control commands are transmitted over the internal data bus  52  to the process module controller  60 . Since the basis controller  50  is responsible for all process modules  30  connected to the processing station  18 , the different programs of the process modules  30  in this case are carried out sequentially, so that problems can arise with functions of a process module  30  which are critical with respect to time. This situation can be alleviated by providing several program control units  76 , i.e. microcomputers, in the basis controller  50  (multiprocessor system), apart from the mentioned placement of the program control unit  76  in the respective process module  30 . 
   With reference to the schematic illustration in  FIG. 4A , the structure of the process module controller  60  will be described in the following as well as how the program necessary for control reaches the program control units  76 . For simplification, the parts already discussed in conjunction with  FIG. 3  have the same reference numerals in  FIG. 4A , so that a detailed description need not be repeated. 
   Each process module  30  comprises a process module controller  60  which includes among others a control unit  70 , a program memory  72  as well as a program data administrator unit  74 . The program memory  72  is a non-volatile memory, for example in the form of a ROM, EE-PROM or a hard disk memory in which the necessary program for controlling the process module  30  is stored. The program data administrator unit  74  in the simplest case is a memory unit containing various data specific to the process module. For example, this data includes a name identifying the process module  30 , a value indicating the location of the program and a value indicating the location of the program control unit  76  for executing the program. 
   In the present embodiment, the basis controller  50  comprises a program control unit  76 . Furthermore, the lower process module  30  in  FIG. 4A  comprises a program data unit  76 ′, which is part of the process module controller  60 . 
   As can be seen in  FIG. 4A , the central control system  40  can be connected to the Internet  80  through a server  82 , where the server  82  comprises a program memory  72 ′. As indicated with dashed lines, the basis controller  50  or the central control system  40  can also include program memories  72 ″ and  72 ′″, in which programs necessary for controlling the process module  30  are stored. 
   All of the units connected to the data bus  42  have interfaces  84  which control the communication over the data bus  42 . 
     FIG. 4B  illustrates a modification of the embodiment shown in  FIG. 4A . For simplification, the same parts are indicated with the same reference numerals, so that a repeated description of these parts is not necessary. In contrast to the embodiment of  FIG. 4A , this modification no longer comprises a basis controller  50 . The functionality of the basis controller  50  is completely transferred to the process module  30  and/or the central control system  40 . Due to this, each process module  30  has a program memory  72 , a program data administrator unit  72  and a program control unit  76 . This results in a completely decentralised structure of the entire system. The process modules  30  are therefore autark. The function itself however is not substantially changed with respect to the embodiment shown in  FIG. 4A , only the data flow transmitted over the data bus  52  is reduced. In addition, the process modules  30  communicate over this data bus  52  both with one another and also with the central control system  40 . Due to the small difference between the embodiments of  FIGS. 4A and 4B , the start up of the process module  30  is described below in conjunction with the system shown in  FIG. 4A . The functions of the basis controller  50  indicated there are performed decentrally in the embodiment of  FIG. 4B , i.e. by the process module itself or for example by the central control system  40 . 
   The start up of a process module  30  is accomplished as follows. The process module  30  or the process modules  30  are first placed in the processing station  18  and connected by the plug connectors  34 ,  36  to the supply trains  24 ,  26 . When turning on the process module  30 , the process module controller  60  accesses the basis controller  50  over the data bus  42  or over the internal data bus  52  (or the other process modules or the central control system  40 , when no basis controller  50  is present as in  FIG. 4B ). The basis controller  50  (in  FIG. 4B  the process module controller  60  itself or the central control system  40 ) reads out the data stored in the program data administrator unit  74  and depending on the data transfers the program data out of the program memory  72  into the program control unit  76 . Alternatively, and depending on the data stored in the program data administrator unit  74 , the program can also be downloaded from the program memory  72 ′, the program memory  72 ″ or the program memory  72 ′″ of the central control system  40 , where in the first case, the central control system  40  establishes a connection to the Internet  80  over the server  82 . It is also possible that the process module  30  could establish a connection to the Internet independently without the central control system  40 . The information as to where the program is located is therefore found in the program data administrator unit  74  for each process module  30 . In addition, the program data administrator unit  74  also indicates where the program control unit  76  is located. For example, the program control unit  76 ′ in the lower process module  30  is part of the process module controller, so that the program is transferred out of the program memory  72  into the program control unit  76 ′. 
   The mentioned procedure of transferring the program out of the program memory  72  into the program control unit  76  runs automatically without action of an operator. In particular, it is no longer necessary that the program for controlling the process module  30  be loaded by an operating person from a notebook into the program control unit  76  and for example making program adaptations. 
   After the programs for the different process modules are loaded in the program control units  76 ′ of the process modules  30 , they are started and cyclically repeated. The programs then activate the step motor  62  of the process module  30 , properly move the laser  86  for marking and provide for the reading out and analysis of data measured on a scale  88 . 
   The program data administrator unit  74  has been described as a simple memory unit, which contains data specific to the process module. Alternatively, the program data administrator unit  74  can be an active unit, which undertakes the mentioned tasks of the basis controller  50 , namely the transfer of the program out of the corresponding program memories  72  into the program control unit  76 . 
   It will be understood that other task distributions between the program data administrator unit  74  and the basis controller  50  are possible. In conjunction with the present invention, it is only important that the program be automatically read out of the program memory  72  depending on the information stored in the program data administrator unit  74 , where the program memory  72  is part of the processing facility  10 . 
   In summary, it is found that the control structure of the process module  30  according to the invention leads to a distinct simplification of the start up procedure. It is no longer necessary for trained personnel to read in the necessary programs from a notebook, so that costs can be saved and on the other hand a possible source of error is eliminated (plug and work). Furthermore, each process module  30  has all of the necessary components for testing when located outside of the processing station  18 .