FR2552243A1 - METHOD FOR CONTROLLING INTEGRATED MANUFACTURING PLANTS, AND DEVICE FOR IMPLEMENTING IT - Google Patents

Abstract

THE INVENTION RELATES TO THE CONTROL OF MANUFACTURING LINES. IT RELATES TO A PROCESS WHICH INCLUDES THE PLANNING OF WORKSTATIONS 21-27 AND THE MOVEMENTS OF PARTS 15 BY SIMULATION OF WORK PLANS IN A COMPUTER, USING INFORMATION CONCERNING THE OPERATIONS TO BE PERFORMED. THE SELECTED PROGRAM IS EXECUTED DURING THE REAL OPERATION OF THE INSTALLATION AND IN SYNCHRONISM. CONTROL DEVICES 20, 32, 33, 46 DETERMINE EVENTS FOR THE CONTROL OF THE OPERATION. APPLICATION TO MANUFACTURING LINES, ESPECIALLY TEXTILE PRODUCTS.

Description

The present invention relates to a plant control method

  integrated manufacturing unit which comprises a processing unit comprising a transport device for advancing the parts provided 5 and a number of workstations for performing a number of operations on the parts, the transport device being intended for be addressed to transport the pieces to selected work stations according to a predetermined schedule so that the particular operations of the individual pieces are performed. The method includes planning the thoughtful construction of the installation, with respect to relates to workstations and operation, the transport of parts by the transport device 15 being taken into consideration, at the various workstations, by simulation of the work plan in a computer with use of established data, received in the computer and concerning operations necessary for the treatment of the parts, data p on the operations themselves, as well as information on the proper construction and

to perform these operations.

  The invention also relates to a device for the implementation of this control method of integrated installations, the device comprising a processing unit which comprises a device for transporting parts used during manufacture and a certain number of workstations intended to perform operations on the parts The transport device 30 is intended to be addressed by an addressing apparatus so that the parts are transported to selected work stations according to a predetermined program ensuring execution of particular operations to individual pieces. The use of integrated manufacturing facilities for objects on an industrial scale has long been known. Such production lines comprise

  several workstations in which a blank is machined or processed so that the desired object is formed.

  In some cases, such production lines are intended for the manufacture of a finished object from the raw material, but in other cases only certain processing operations are performed, for example the manufacture of the object. finished from a semi-finished object, making a semifinished object from untreated or only partially processed blanks, or a partial treatment such as a surface finish,

  control operations or conditioning.

  Typically, in this production line, the workpiece advances along a transport path on which it passes at a number of workstations to which it is successively subjected to processing operations necessary for The processing plant required for these operations must therefore include both a transport device for moving the workpiece along the transport path and a number of workstations. The operations may be longer than others so that some workstations must be multiplied so that they allow the direction of the room current along several parallel paths when performing the operation. devices for forming queues, in which parts can be assembled between the stations so that differences in processing times are regularized When the workstations are implemented manually,

  attempts are made to plan individual operations so that the various operations have optimal equal times as far as possible so that waiting times and insufficient capacity utilization of some stations are reduced.

  It is sometimes desirable, for the treatment of objects different from each other, to be able to vary the operations performed along the production line. For example, it may be desirable to manufacture different or different objects simultaneously and to mix them together. According to various criteria In other cases, it may be desirable to manufacture small series of different or different objects, successively, or alternately in small series and in large series. These operations can be carried out by carrying out certain items so that they execute alternating operations or by performing other workstations for other operations, and in this case the paths followed by the parts at the various stations are controlled. Therefore, of course, both methods can be used in the same plant. In addition, in installations which are not performed directly for such a variety of manufacture, it may be necessary to change the treatment process in time. in a minor or important way, for example as a result of

  model change of the manufactured object.

  Treatment facilities of the type considered constitute a complex system. It is desired to carry out such installations in such a way that they give satisfactory and preferably optimal results as regards the volume of manufacture, in relation to the resources used. Minimize the risk of disruption during processing operations The degree of complication increases when the number of treatment stations increases, and becomes particularly important when various processing operations are to be performed Achieving satisfactory results essentially requires that the installation is thoughtfully designed with regard to the selection of workstations and other apparatus, and the planning of the transport diagram. Next, control is necessary for

  verification of the actual achievement of the desired results and the fact that the installation operates without disturbance.

  In the event of disturbances, they must be able to be eliminated as soon as possible, in the case of temporary defects by the use of measurements.

  corrective measures and in the case of defects in the installation by modification of the installation itself or of the operation carried out.

  It is already known to use a simulated operation of an installation model for the systematic verification of various construction alternatives in order to obtain optimal results during the design of the installation. The use of computers for such a simulated operation is excellent for establishing the conditions which should give optimal results in the installation, under certain predetermined conditions The actual installation is then carried out according to the results obtained during the simulated operation When it has been possible to establish such conditions so that they correspond very well to the actual and future operating conditions, the design based on such a simulation carried out using computers has shown that it gives excellent results The disturbances that nevertheless appear during operation 25 of the installation are removed by eliminating the sources of Disruption when they occur There is no need to question the adopted and established set of the installation. In other words, an installation performed on the basis of a properly conducted computer simulation usually gives the expected result after a certain period of

on the way.

  In the type of manufacture of several small series, alternately fast, or when the objects to be formed have some individual modifications, sometimes in the form of a very large number of variants, it is obviously particularly interesting to be able to use a simulation on computer for the design of the installation and for the determination of the course of operations necessary for the manufacture of objects with their various variants Despite the 5 excellent conditions indicated previously, the simulation on

  computer did not show the expected success in the real tests of realization of facilities intended for a very diverse production, with optimal results.

  This is due to the difficulty of taking into account, by computer simulation, all the irrational factors appearing during actual operation and causing disruption of operations while requiring certain adjustments at start-up Difficulties of this nature Each time a new manufacturing program is adopted, this is all the more annoying as the program changes.

are frequent.

  The subject of the invention is a method for controlling integrated manufacturing installations, making it possible to use the advantages of computer simulation, even in a production involving operations.

  very diverse and small successive series.

  The invention therefore relates to a process which makes it possible to implement an installation immediately or after a short period of time in the exact manner established.

  during the computer simulation, and the maintenance of this operation during the entire period during which the adopted working method is to be used.

  It also relates to a device for the implementation of the aforementioned method.

  More specifically, the invention relates to a method such that a computer program chosen for the operation of the installation represents an established work plan, and this plan is executed during the actual operation of the installation and in synchronism with this, the installation having a number of control devices for recording the data relating to the events that actually take place in the installation, for example the passage of rooms and their rest in certain sections of the installation, the control devices being connected to the computer and being used for transmitting thereto data to enable comparison of the actual operation and the result given to the operation according to the simulated work plan and to the results established during this simulated operation, the device comprising an indicative element which is connected to the computer and which, following a sig nal from the computer and indicating a lack of agreement between the real and simulated work data, indicates a malfunction and thus triggers manual and / or automatic corrective measures so that the operation corresponds to the

  planned program of simulated operation.

  The device according to the invention comprises, in a known manner, a computer intended to receive data concerning the parts to be processed in the installation, relating to the necessary work operations, data concerning the respective work operations and relating to factors such as that the working interval, the necessary machines and tools to be used and, where appropriate, the competence of the operator, data concerning the transport device and in particular factors such as the transport interval corresponding to the transport. between respective workstations and in such workstations intended to perform the operations, the computer being intended to simulate worktables which control the characteristics

  during operation and transport so that the respective parts undergo the treatment adopted with establishment of a reflected work plan which regulates the operation of the installation 35 with the aid of this simulation. a control device, preferably in the form of sensors.

  These are intended to transfer information to the computer, this information concerning the advance provided by the transport device and the passage of parts to certain verification points of the installation, as well as the identification of the parts transmitted to the computer. the installation, the computer, when receiving the information from the control device, being intended to control the execution of the adopted work plan in synchronism with the actual events in the installation, with comparison of the work plan and actual operation, the device 10 further comprising an indicating device for displaying information indicating a lack of agreement between the work plan executed by the computer and

  the actual simultaneous operation of the installation.

  Other features and advantages of the invention will be better understood on reading the description.

  which will follow examples of embodiment and with reference to the accompanying drawings in which: Figure 1 shows a workstation of a treatment facility; Figure 2 is a diagram of the entire installation; Figures 3 and 4 show two alternative embodiments corresponding to the diagram of Figure 2; and

  Figure 5 is a diagram showing the device incorporated in the entire installation.

  FIG. 1 represents an example of a workstation that can be incorporated in an installation to which the invention can be applied. The installation comprises a main conveyor 1 whose main part is formed of a rail 2 preferably forming a endless loop (only part of the main transport rail is shown in FIG. 1) The rail surrounds a driving member in the form of a cable, chain or equivalent device that moves continuously 35 inside the rail 2 and along it by moving a number of hooks 3 which protrude along the rail These hooks 3 are intended to carry product brackets 4 which slide along the rail 2 on The supports are intended to carry the parts 15 to be treated in the installation. FIG. 1 shows the parts 15 in the form of textile parts which form a shirt when they are sewn. 5 A derivative carrier 5 from the carrier

  Main 1 at each workstation of the installation.

  Each derived carrier has an input switching point which includes a rail section 6 which can be lowered to the main conveyor, and an actuating device 7. The switch 6, 7 is followed by an input part. 8 of the rail 9 which goes down in front of the workstation Part 8 goes back to a stop position represented by a stop member 10 Shortly thereafter, the rail 9 has a portion 11 which rises. a distribution part 12 which goes down over the rail 2 of the main conveyor The switching point 6 can be moved between two positions, one in which it is raised above the rail 2 of the main conveyor as the in20 dique Figure 1 and a second position in which its free end is against the rail 2 In the first position, the point 6 allows the supports to continue along the main carrier without stopping in the second position, sup The ports are guided at point 6 and, when they reach the downward portion of the rail 9, they descend and come against the stop member. The switching point 6 is lowered when the operating device 7 has indicated that the support which is close to the derived conveyor must be transmitted to the associated workstation. This can be done in various ways, but in FIG. 1 a mechanism has been mentioned which includes guide cams which can be advanced or retracted on the support member, these cams being able to exit to an external position or to return to an internal position, so that they cooperate or not with the Celuici operating device 7, when it comes into abutment against the device with a predetermined combination protruding cams, that is to say in an external position on the series of cams, controls the lowering of the switching point 6 When no combination is made, the switching point 6 In this way, product supports that have

  suitable codes to which products are suspended can pass on the desired derived carrier to reach the desired work station. In the following, this predetermined displacement to the selected shunters is called "addressing".

  The stop member or element 10 forms a holding point of the supports. When the person at the workstation wishes to treat the product suspended from the support closest to the abutment member, several supports may form a support. After the stop member, the product can be moved to a position suitable for its processing. The workpiece 15 can then be processed. The figure shows a sewing operation performed with a sewing machine 16 which constitutes the apparatus of this invention. workstation The sewing machine is served by an operator When the work to be done at this position is completed, the product can advance following the operation of a pedal 55 It is then released and slides towards the rail 9 which is found below. The product support, so that it reaches the next work station during the planned operating cycle, must be readdressed when using the aforementioned addressing mechanism, and the operation is carried out when the product goes into operation. In this set, a number of cams can be protruded or recessed by means of keys which control the displacement of the cams of the supports when they pass in front of the assembly. The cams of the support, when so moved, then form a new combination suitable for transporting the product support to the station.

next work.

  When the piece has yet to advance, the support 4 is transported from the bottom of the rail 9 along its upward portion 11. The feed is carried out by driving hooks 18 which make a movement 5 of going back and forth along the Part 11 of the rail The stroke is sufficient for the support is taken by the lower hook which can be folded and transported to a locking member 19 so that it is then gripped by the upper hook and transported in the distribution part 12. , it descends on the rail 2 of the main conveyor 1 and continues along it to the next post corresponding to his address This provision is described in more detail

in Swedish Patent No. 352,052.

  FIG. 2 represents a possible composition of a processing plant as a whole. This figure shows the loop-shaped main conveyor 1 and a number of shunters 5 which reach a number of workstations or go into 2 of these stations can be controlled by an operator (indicated by a circle 28), while the operation of other stations, for example the stations 23 and 24, can be controlled by an operator (indicated by a circle 28). FIG. 2 also shows the working positions of the products, represented by the abutment element 10, and the relocation assembly 17 in the inlet part 8 and the outlet part 11 of the derivative conveyors. sensor detection devices 20 are also arranged as also shown in FIG.

  FIGS. show a supply assembly and an exhaust assembly 31 These assemblies have separate detection devices 32 and 33 The main conveyor 11 also has a sensor 37 Sensors 20, 35, 32, 33 and 37 are described in more detail in the remainder of this memoir.

  The feed assembly is intended to allow the entry of new product carriers on the main conveyor 1 when new parts have to be transmitted to the installation. A set of this type can be mechanical but it is not This is because the main conveyor can receive new manually placed parts from a neighboring stock of parts or semi-products. The evacuation assembly 32 is intended to receive the parts that have been processed throughout the program and which Therefore, the evacuation assembly 32 preferably has a bypass chain 34 on which the supports can be stored and to which they are addressed in the manner previously described. with reference to the workstations In this case too, a

  Manual processing of finished products is possible and the finished products are then removed from the main carrier by hand for later transport.

  During the operation of the installation, the parts are thus successively transmitted to the main conveyor 1 and are then transported to the selected workstations to which the desired processing takes place. The operations need not be performed in the sequence formed by the respective stations. The supports can pass several times around the main carrier and can return to positions to which they have already been passed. When all the operations have been performed on the parts, the corresponding support 30 is transmitted to the final address which is

evacuation assembly 31.

  The possible arrangement of the carrier for conveying goods along a main conveyor and to selected work stations to which they are addressed has been described. This provision permits the construction of a processing plant having on the one hand a device for transporting parts

  and on the other hand workstations in which predetermined operations are executed successively.

  The installation is of a type in which the parts, depending on the necessary processing, can be transferred to all workstations or only some, in a predetermined sequence. The realization of the stations so that they allow various operations, for example. Excluding certain operations, certain parts passing bypass to the associated work stations 10 on the main conveyor, allows, without any change of the installation and by simple selective addressing of the parts, the execution of different types of processing operations, in variable numbers, on the parts transmitted successively to the installation Significant changes in the operations or the nature of the processing can be performed by modifying the workstations as a whole, for example by modifying the specifications of the task to be performed and operations carried out at manual posts, by exchange of tools, by 20 users more or less of the available processing capacity or by exchange of the machinery and apparatus used. The transport mechanism can also be adapted

  to transport parts to identical but duplicate positions, chosen according to the available capacity.

  The realization of the installation in this way makes it possible to move from manufacture to different types of parts, requiring treatment of a different degree, by adjusting the transport mechanism, sometimes supplemented by modifications of the workstation and in particular operations performed at this station Parts can also be mixed, each addressed to the workstation corresponding to the operation to be performed

on her.

  It has been indicated that the treatment of different parts can be executed in the installation. The term "treatment" is used in its most general sense.

  As indicated initially, the treatment can be of very different types, ranging from manufacturing operations such as assembly, assembly, verification and adjustment of a complete product, from the raw material, to more limited operations such as simple assembly and packaging The type of treatment, machining or operations to be performed on the parts determines the layout and construction of the workstations while the principle of operation of trans10 carrier, with the possibility of addressing parts,

remains the same.

  An example embodiment of the conveyor has been described. This example applies to the garment industry. Other types of products require a corresponding modification of the conveyor A common type of transport mechanism used for the advance of various types of conveyor parts is the conveyor belt, which differs from the suspended conveyor shown The conveyor belt conveyor must be equipped with switches, bypass conveyors,

  pushers and similar devices for distributing the parts to the various workstations In reading the following description of the control method of the installation according to the invention, it should be considered that the nature, arrangement and construction

  of the installation used and its process of implementation

  may vary widely.

  In an installation of the type under consideration, different work cycles, often in a very short sequence, must be able to be performed. In some manufacturing operations, very short series of objects can be manufactured daily. The first type often corresponds to the clothing industry in which clothes of various styles, of different materials and of different sizes are produced in relatively small series. This latter case often occurs in the clothing industry. for example in the mounting of devices because a basic model is

  modified according to the orders to be satisfied.

  The method according to the invention and the device intended for its implementation are intended for the rapid and rational establishment of the optimal implementation for each type of part, as well as the establishment of the data necessary for the control of the arrangement. of the installation, including transport routes and the construction and layout of workstations. It must also be possible to use the program obtained for

  operation of the installation during its order.

  The process has the following main characteristics. The necessary processing steps of each type of workpiece are determined.

  means that the data concerning the nature of the operations, the duration of the various operations and, when they are interdependent, the sequence of execution of the operations, must be established.

  B In the case of several types of parts,

  that is to say, in the case of variants and modifications of a model or of a basic design, which must be manufactured simultaneously, the sorting to be used is established and, consequently, the operations to be modified in the assortment 25 are determined.

  C The data necessary for the manufacture of the parts of the set and concerning the transport paths are established The types of supports that are necessary for the treated product are then determined. 30 D According to the steps to be performed and, where

  where appropriate, their modifications, the types of workstations required in the installation are determined.

  Simultaneously, equipment, for example tools,

  etc., is determined for the various positions.

  E Likewise, according to the different stages foreseen and the determined choice of the workstation, the necessary labor force is determined in this respect,

  the particular skill required for certain positions is determined and the manpower with the necessary skills available is also determined.

  The capacity of the workforce can be studied, thus making it possible to adapt the duration of the operations to

  the capacity and experience of available staff.

  F The necessary data for the carrier is then determined In particular, it must be determined which type of support is to be used according to the assortment of parts to be manufactured (see point C). various sections of carrier from

  plan must also be available.

  G The current state of the installation is established, that is, its construction and layout for the

  previous series of products.

  As far as possible, the irregular situations which may arise must be determined and the most frequent situations of this type at least are determined.

  the defects of a part transmitted to the installation or the transmission of an erroneous part, the defects appearing at the workstations, and requiring a replacement of tools, the unplanned but necessary interruptions of the work of the workers, and the breakdowns of the carrier.

  Corrective measures must be determined to compensate for these possible defects It may be advantageous to distinguish between temporary defects and defects due to the nature of the installation The first 30 require individual and occasional corrective measures while the others require the change of the operation so that defects of

  same nature do not appear later.

  From the data set forth in A to H as previously indicated, the rational planning of the workpiece processing and its movements in the plant are established. In this regard, both the layout of the plant and thus the selection of workstations and their apparatus, so that, in addition to the immediate needs for the various work steps, precautions must also be taken to avoid unnecessary modifications of the installation, that is, ie the current state of the installation must be taken into consideration (G) The assignment of staff to the workstations must be determined on the basis of the necessary experience and competence, the capacity required and the availability Likewise, the necessary nature and design of the carrier must be established, for example the

type of media needed.

  Taking into account the design factors makes it possible initially to determine the

  the necessary construction and layout of the installation with regard to the product or the various products to be manufactured during the planned period.

  In addition to the paths of the products in the installation 20 are determined taking into account the workstations to which

  Each piece must pass. The necessary sequence of workstations must also be considered. The transport path must be planned so that it avoids superfluous movements and provides minimal work and transport time.

  One of the aims of the process is precisely an optimal treatment plan by the aforementioned planning, as well as the verification that the work plan is well followed. This requires the verification of the advance of the processes. products in

  In addition, it may be necessary to check the products at various points of the installation so that, when the various operations have been performed, it is determined that the parts have been processed as intended.

  K The operation of the installation begins

following the plan prepared.

  L Checks on the execution of treatment according to the plan are carried out constantly during operation When the checks indicate irregularities, they are indicated so that corrective measures can be taken They can be carried out manually or, in some cases, by a automatic device, for example by inverting a path

  or a transport, as described below.

  The planning of the construction and layout of an installation so that it is suitable for the execution of the specified tasks on workpieces, as indicated in the preceding paragraphs A to I, is already known. have proved very useful in these planning operations The available fundamental data can be transmitted

  to the computer which then calculates the plan variants while evaluating the results to enable the establishment of an optimal operating plan for the facility, as well as the most useful construction and layout.

  This method of establishing the operating mode is usually called "computer simulation." This is an excellent support, but the resulting work plan requires a lot of manual work before it can be put into practice and requires the performance of verifications during operation and during the start-up of the installation, based on the experience gained from the operation. The invention also makes it possible to rationalize in these fields. The main devices used for this purpose are

The following.

  The work plan is prepared, including possible foreseeable irregularities, that is, defects that may occur during operation. Alarms related to these defects are established and, to the extent necessary, the directions of the corrective measures or the data controlling the corrective pulses are determined. The operating plan is also prepared with regard to the functions of the various control devices and verification and their positions in the installation so that defects can be determined during processing and at a point of delivery

  suitable for the correction of the respective defect.

  The installation is equipped with adjustment and verification devices for the aforementioned functions. The adjustment and verification devices may be of several main types, for example a device intended to record the passage of a certain product at a certain point in time. along the path of transportation and a device for recording the status of the respective products at a certain point along the path The first type of verification device should simply indicate the movements of the various products or their support in the installation of this way, errors on the transport paths can be indicated as well as unplanned queues at the workstations 20 and losses of products during transport which may be due for example to a fall of the support The second type of device Verification allows the verification of the functioning of workstations, as these are suitably In other words, this type of verification device is a type of inspection device. It may be an automatic measurement and control device. Preferably, the installation and in particular the conveyor mechanism comprise a device for transmitting synchronization pulses to the computer so that it allows the work program to advance.

  at the operating frequency of the installation.

  It is also possible to incorporate in the category of 35 verification and control devices the system

  of communication placed at the different points of work when these are commanded by a manpower.

  Such communication systems, including for example a keypad, enable an operator to transmit work status information. In this manner, information about faults, errors, interrupts of processing, or other data. of interest for the proper operation of the installation and its results can be transmitted and can be part of the monitoring of the operation of the installation executed by the computer The inspection stations, when they are staffed, should preferably to be equipped

  analogous communication systems.

  c A visualization equipment that is

  connected to the computer which allows the establishment of the work plan and to which the verifiers are connected, is intended to trigger an alarm when defects appear, by indicating the nature of the defects and preferably the possible correction of these defects.

  The display apparatus of this type preferably comprises one or more screens on which the information relating to the operation of the installation is displayed after processing by the computer of the reports transmitted by the control and verification devices (b). With comparison of the simulated program to actual operation screens of this type can be placed at a central location as well as at least at the control stations.

  In addition, a certain type of alarm device, for example acoustic alarms or flashing lamps, may be placed so that it draws attention to faults requiring immediate action so that major interruptions may occur. the operation of the installation is avoided.

  d Facilities with highly automated operation may have a device connected to the computer as described in (c) as previously described and which are intended to undertake corrective actions automatically upon occurrence of defects, thereby rendering redundant manual measurements, at least

  for a certain time Examples of such measures are the resumption of the routing along the transport paths in the device so that the parts advance to another workstation by going beyond the station 5 which does not work Another type of measurements correctives can be an automatic change of tools.

  The computer makes it possible to display the data received during operation. The data of this type can be reports on the production, for example the number and type of products manufactured during a period of time.

  defined period, planned production including the time when it is completed and reports of the occurrence of disturbances affecting production. Such equipment may also be used for personal reports and data on wages and salaries.

  In this case, the computer can be connected to a printer for giving information on documents.

  A working list concerning future periods

  can be prepared in this way.

  The drawings represent an embodiment of verification and control device corresponding to paragraph (b). For example, the device which records the passage of a certain product at a particular point along the transport path, for example the sensors. 20, is shown as indicated by

  In both Figures 1 and 2, these sensors are placed at the input and output of the shunt carrier 5.

  This allows the product to be recorded to pass both when it enters the workstation and when it leaves it to be routed on the main conveyor. The sensors 20 can be adapted to operate in two different ways. the passage of a medium of the product is recorded without individual identification, ie the transported product is recorded. The information transmitted to the computer and concerning the positions of the individual parts must always be updated so that the computer can perform the necessary tasks, ie control of the operation of the installation and transmission of information on the results of production However, this can not be achieved without direct identification because the computer can always calculate the likely position and probable point of passage of a given medium When the computer is synchronized on the main carrier and the When the identity of the product is transmitted to the computer when the product is transmitted on the main conveyor (at 30 in FIG. 2), the computer, according to the synchronization pulses, can calculate continuously the advance of the product along the vertical conveyor and, as a result of the information transmitted concerning the addresses of the medium, the computer can determine the moment at which the medium is transmitted to a shunt carrier and, according to its knowledge of the necessary time of rest at the workstation, the computer can calculate the time that elapses before the support is returned to the main conveyor 20 and therefore passes in front of the associated sensor The mounting of a sensor also at the entrance The shunting carrier as discussed above provides additional verification that a part has actually entered a certain workstation. Alternatively, when using a single heading. he can

  be at the input of the shunt carrier.

  However, when it is desirable that the product supports undergo individual and direct verification, for example in the case where the rest at the workstations can not be established beforehand with the necessary precision, the sensors can be adapted to the contrary. To this end, the latter have identification devices 38 (FIG. 1) such as a bar code 35 which can be read by the sensor 20 during the passage of the support. The computer can also be used. in this case so that it carries out probability calculations concerning the moment of the passage of a determined medium for this purpose, it is not necessary for the computer to identify the signal emitted by the sensor by means of the question "What support does it go through?" but on the contrary with the help of the question "has some support gone?" This is advantageous because the reading of an identification device that passes in the form of barcodes or other types is not always reliable in the current state of the art. The computer can be adapted to the interpretation of a vague signal as being suitable, taking into account predetermined limits. The work of the computer is also facilitated, with reduced processing times, when it is not necessary that the signal from the computer forces it to search the entire register for corresponding product media, but the processing may instead be

  limited to the verification of a limited number of likely media or a single medium if any.

  It has also been indicated previously that sensors 32 and 33 are located at the input assembly 20 and the output assembly 31.

  output can be of the same type as the sensors 20.

  On the other hand, the sensor 32 of the input assembly can be adapted to the direct identification of the parts introduced. In particular, in the case of a mixed production or small series, it is necessary that the nature of each The part must be determined so that it can be properly addressed to the workstations and so that its advance in the installation is properly controlled by the computer. In series of several parts which must be treated identically,

  this identification can obviously be made collectively for all the pieces of the series.

  The identification of the parts transmitted to the installation can be carried out in a variety of ways. One suitable way is to use a separate terminal which is used to produce information on the type of the part, whether alone or in a series, which must be introduced into the installation The terminal may have a keyboard allowing the introduction of information concerning the identification of the room, or may have a reading device and, in this case, each room 5 carries a identification device such as a magnetic card When sensors of the aforementioned simpler type are used in the installation, the probability calculation concerning the positions of the supports in the installation begins after the passage recorded by the sensor 32 When the sensors used are of the direct-identification type, the computer must receive information relating to the identity of the medium and at the same time to the type product associated with it, when the media are transmitted in the installation. In a variant, when the identification of the supports is carried out by means of a code, it can be connected to a certain type of product. In this case, it is necessary to use, for each type of part, supports Exactly the code corresponding to this particular type of part The relationship between the code and the nature of the part is preferably stored in the computer's memory and allows it to immediately determine the nature of the transmitted media.

  in the installation in front of the sensor 32.

  FIG. 2 shows an additional verification device 37 as indicated in paragraph (b). This device 37 is intended to be used for synchronization. It is preferably a photoelectric cell which emits a signal whenever a rolling hook 3 (FIG. 1) passes in front of the cell,

  thereby recording the advance of the main carrier.

  FIG. 5 diagrammatically represents the entire device (of the processing unit of which only the lower part in FIG. 2 is indicated). As shown, the installation is connected to the computer bearing the reference 40 via of its control device, that is to say via the sensors 20, 32, 33 and 37 The computer has a memory 41 which receives the data concerning the workstations, the operations, etc., especially the normal durations and the apparatus necessary for the treatment The computer simulation can be carried out according to these

  data A manual keyboard 42 allows communication with the computer and the results of these activities can be displayed on a screen 43 and / or on a printer 44.

  As previously described, a communication unit 46 may be coupled to the computer and preferably includes keyboards placed at workstations with workers, and at these stations certain information transmitted by the computer may also be indicated on a device. 47 viewing such as a screen. It has also been indicated previously that the device must comprise an indicating or display device which, during operation, makes it possible to identify operational irregularities as well as the corrective measures to be taken. As an indicator device of this type, it is possible to use screen 43 and at the posts to which

  47 In one example, it has been indicated that the installation could comprise an alarm device such as a bell 45 allowing an alarm to sound as soon as immediate actions are necessary.

  Figures 3 and 4 show two applications of the installation shown in Figure 2 In Figure 3, the solid line indicates the path of the products in the installation It appears that, compared with Figure 2, the station 22 of work is changed since it is no longer manual but automatic, such as items 23 and 24 The manual 25 also has an operator on

Figure 3.

  In operation, the workpieces 35 are transmitted to the assembly 30 They move along the main conveyor 1 whose operation causes the transmission of synchronization pulses

  to the computer via the sensor 37.

  The program constituting the basis for the planning of the installation and the progress of the transport is carried out in the computer. According to this transport procedure, the supports having the products suspended there are transported along the conveyors 5 and to the corresponding posts. In the latter, the treatment is carried out and the supports advance on the main conveyor 1 and, in this operation, they pass in front of the associated sensors. The product is then identified with the aid of the support associated with one of them. described above and the computer can record the fact that the products have reached the workstations according to the work plan, if they have been treated as intended and if they have moved from the workstation to the workstation.

  work When this is not the case in the period determined in the operating plan formed by simulation, this indicates the existence of a defect or an error.

  Given the disagreement between the actual events and the work plan, a pulse is transmitted by the computer and alerts the staff who can correct the fault.

  As previously stated, other corrective measures

  can be taken automatically.

  For example, if the processing at station 22 is to be performed, for whatever reason, prior to processing at station 21, the addressing may be performed so that the pieces first pass to station 22, without stopping at Then they can go through the main conveyor throughout the loop and can return to station 21 to undergo the operation.

  necessary on the other hand, the exchange between the stations 21 and 22 may have greater disadvantages than the simple lengthening of the path.

  As mentioned above, there are other possibilities than sensors for the computer to take corrective action in the event of unforeseen events. For example, the installation may include an inspection and quality control device. where an operator is located, facilities may allow staff to provide information on the appearance of faults, lack of material or the like, and the need for a shutdown.

  In the foregoing description, the most rational method for this purpose is the direct communication with the computer by means of a terminal. In this way, attention can be drawn to this situation so that suitable measurements can be made. In some cases,

  the computer can also be adapted to direct the product stream to a storage area or can form media queues until the normal flow

can be resumed.

  Figure 4 shows the treatment at most

  As a result, items 21, 24, and 27 are skipped. In other words, these items are idle. In a variant, the items 21, 22, and 23, 24 are in a different form. respectively can form chains in parallel.

  If the processing time at one of the stations is much longer than that of the stations 25 and 26, these stations, represented as having an operator, therefore work empty for a certain period. This can be avoided provided that additional tasks are given

  at these positions but, in a variant, by doubling the positions at which the processing time is longer.

  The computer can then choose which one of the two doubled positions is free when a new product is transposed.

  The example described, which relates to the garment industry, uses mechanical addressing equipment for the distribution of parts to the various workstations. Thus, the computer is not used for the direct control of the machines. The control of the work done at the various workstations is not carried out either, other than via messages from the computer and transmitted to the posts with personnel or supervisory staff. The computer is indicated if the planned operation and workflow are properly ensured when the planning has been done using the simulation. This separation of the mechanical control from the planning and the computer control has considerable advantages. The mechanical control systems are very robust and reliable and rely on a well-proven technology. They do not require complicated wiring and electrical devices such as electromagnets and motors, can be largely removed The control device does not depend on a central part and the risk of sagging

  total or breakup is therefore virtually out of the question.

  Even if the set including the computer does not work, the installation may continue to work, but without the control function provided by the computer. However, the invention also applies to the total control of the operation of the computer installation, in addition to the aforementioned command. The computer is then adapted so that it emits control pulses and the apparatus of Addressing of the transport device 25 is then sensitive to these pulses. The control of the automatic functions inside the workstations can then be integrated with control by the computer.

  this command using a computer.

  Of course, various modifications can

  to those skilled in the art to the devices and methods that have just been described by way of non-limiting examples without departing from the scope of the invention.

Claims (8)

  A manufacturing plant control method, comprising a transport device (1, 5) for advancing the intended parts (15) and a number of work stations (21-27) for executing a number of of parts operations, the conveying device being intended to be addressed so that it transports the parts to selected work stations according to a predetermined program providing for the execution of particular operations on the individual parts, the method comprising the planning of the reflected construction of the plant with respect to the workstations and their implementation taking into account the transport of the parts by the transport device 15 to the various workstations, by simulation of work plans in a computer (40, 41) using established data received in the computer and relating to operations to be performed on the parts; operations, and the proper construction and equipment necessary for the workstations to carry out these operations, characterized in that the computer program chosen for the implementation of the installation represents a plan. established, and in that this plane is executed during the actual operation of the installation and in synchronism therewith, the installation having a number of control devices (20, 32, 33, 37, 46 ) intended to record the data of the events actually occurring in the installation such as the passage of parts and their shutdown in certain sections of the installation, the control devices being connected to the computer (40) and being used for the transmission to the computer of data intended to allow the comparison of the actual operation and its results with those of the simulated work plan and its results, the provision f having an indicating device (43, 45, 47) which is maintained in a form connected to the computer and which, following a signal from the computer due to a lack of agreement between the actual data and the simulated work data indicates an operating irregularity and triggers manual and / or automatic correction measurements so that operation is in accordance with the intended simulated operating program.  Method according to Claim 1, characterized in that signals are emitted by the transport device (1, 5) as a result of the movements of its elements.   transport (3), and the signals are used for the synchronization of the work plane executed in the computer (40) and the operation of the installation.   Method according to claim 2, characterized in that synchronization signals are emitted to   convenient intervals to advance the computer program in predetermined time sections.   4 Process according to any one of the preceding claims, characterized in that the momentary positions of the parts (15) in the installation are established in the computer (40, 41) by recording the identity of the parts to the inside the computer at the entrance of the corresponding part in the installation, the computer then being intended to perform a probability calculation concerning the positions of the respective parts in the installation according to the information contained in the computer and relating to the conditions of movement of the transport device (1, 5) and the information transmitted to the computer and concerning the planned downtime of the parts at the selected work stations (21, 27), the latter information being preferably transmitted to the computer by the control devices which are in the form of sensors (20) for detecting the passage of a workpiece (15) or its support (4) in the transport device, when the workpiece or its support enters the respective work stations, leaves or gets in and out.   Method according to any one of claims 1 to 3, characterized in that the momentary positions of the parts (15) in the installation are established in the computer (40) by arrangement, on each piece (15) 5 or its support (4) in the transport device (1, 5),   an identification code which can be registered by the control devices in the form of sensors (20,   32, 33), the code being transmitted to the computer (40) as a corresponding identification signal formed by the controller.   6. Process according to any one of the preceding claims, characterized in that it comprises, in combination, the establishment of data relating to the parts (15) to be treated in the installation and in particular on the operations to be performed. on them,   the establishment of data concerning the operations and relating to factors such as the time of the operation as well as the machinery and tools required and, where appropriate, the competence of the operator, the establishment of data concerning the device transport (1, 5) and in particular such factors as the transport time between respective workstations (21-27) and in these workstations for the execution of the tasks, the transmission of data in the memory (41). ) of the computer (40), the simulation, in the computer (40) of the work plans for the execution of the operations and transport in the installation, during the execution of the determined processing on the parts, the establishment of a well-thought-out work program using simulation, the construction of the installation taking into account the layout of the workstations (21-27) which must perform the specified operations, so that the parts it is the operation of the installation 35 according to the established working plan for the treatment of the respective parts, the unfolding of the worktop in the computer in synchronism with the operation of the installation, the transmission to the computer of control information relating to the progress of processing in the installation, such as information on the momentary positions of the parts in the installation and the progress of the processing operations at the stations of the installation; computer-based comparison of the work plan executed in the computer and the events of the installation during the operation thereof, recorded by the control devices, the recording in the computer of any lack of agreement between the work plan executed in the computer and the actual operation of the installation, and the information, following a verified by supervisory staff, for example using information displayed on a screen, so that corrective   are taken or that devices intended to ensure automatic mechanical correction are triggered.   7 Device for implementing the method   manufacturing apparatus according to any one of claims 1 to 6, the device comprising a processing plant comprising a device (1, 5) for transporting the parts (15) used during manufacture, and a number of stations (21-27) intended for   performing operations on parts, the transport device being intended to be addressed by means of an addressing set so that the parts are transported to the selected work stations according to a predetermined program for execution of particular operations on individual parts, characterized in that it comprises, in a manner known per se, a computer (40, 41) for receiving information corresponding to data relating to the parts (15) to process in the installation and in particular to the necessary processing operations, data relating to the processing operations and concerning factors such as the duration of operations and the necessary machines and tools and, where appropriate, the operator's competence , data relating to the transport device (1, 5) and in particular such factors as the duration and the length of transport between workstations (21). 27) and in these workstations for the execution of the operations, the computer being also intended to simulate work plans for the control of the execution of the operations and transportations by the installation so that the processing adopted respective parts are executed and a working working plane controlling the operation of the plant is established by simulation, the plant having control devices, preferably in the form of sensors (20, 32). , 33, 37) which are intended to transmit to the computer information concerning the advance of the transport device and relating to the passage of parts in front of certain check points in the installation, and to identify the parts (15 ) transmitted to the installation, the computer, as a result of information from the control devices, being intended to execute the adopted work plan in synchronism with the actual events in the installation, with comparison of the work plane to the actual operation, the device further comprising indicating devices (43, 44, 45, 47) for displaying information concerning the lack of agreement between the plan   work performed in the computer and the actual simultaneous operation of the installation.   8 Device according to claim 7, characterized in that the workstations, (21, 22, 25, 26, 27) having an operator comprise a device (46, 47) for communication with the computer, so that data 30 regarding the control of actual operation can   be transmitted to the computer by the communication device, and the indication of a lack of agreement between the work plan and the actual operation, transmitted by the computer, can be displayed via the device of communication.   9 Device according to one of claims 7   and 8, characterized in that the parts (15) or their supports in the transport device (1, 5) comprise an identification device (36) which can be read by the control devices which are advantageously sensors (20, 32, 33) so that the momentary positions of the parts to be recorded in the computer are determined when the parts pass in front of the sensors.   Device according to one of Claims 7 to 9, characterized in that the transport device 10 and its addressing equipment are   mechanical type, and the parts (15) are supported in the transport device by supports (4) each intended to be addressed by means of a code of mechanical switches so that the supports are directed to workstations ( 21-27) or in derivation thereof, whereby the connection of the computer (40, 41) to the installation is essentially limited to communication with the control devices (20, 32, 33, 37).