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RF-ID tag for mould identification |
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The substitution of a mould on the rotary table is an event whose frequency is recently increased due to the following reasons: · The number of pieces for each order is decreased · URGENT order (not planned) from a customer that obliges to:
Production tails due to difference between the planned number of soles to be produced and the real production. PROBLEMS TO BE SOLVED AT FACTORY FLOOR
So far when a
mould is substituted by a new one, it is necessary to reprogram the rotary
table and all the equipments around the table according to the data
associated with that mould. PROBLEMS TO BE SOLVED AT OFFICE FLOOR For the planning office is very difficult to follow the production because they do not have sure and certain data of production. The employee of planning office takes a note of the rounds of the rotary table in the evening. When he comes back in the morning he reads the number of rounds of the rotary table and calculates the production as difference between the two values.This way of calculating the production is not sure and correct for the following reasons: · The difference between the number of rounds is an “average” value that does not take into consideration the history of each mould. (During the night some moulds may have been taken off for a few rounds for maintenance or for cleaning). · If during the night some mould has been substituted, nobody can guarantees that the operator has changed the mould exactly at the planned round. If he changed the mould some rounds later or sooner, some soles will be in excess and some others will be missing (even if the employee of planning office will “presume” a “right” production). If the employee of planning office does not have certain and sure data the following problems can result: · Difficulties in shipping department because the orders are not complete · Possibility of casting soles that were already casted simply because “we don’t find them”. The result of this way of working is: · Waste of time · Loss of production · Waste of money
AUTOMATIC MOULD IDENTIFICATION The introduction of AUTOMATIC MOULD IDENTIFICATION) will solve the previously described problems at factory floor and office floor. FACTORY FLOOR
The aim is
the following: The result can be achieved in this way: 1. Each mould is equipped with a radio frequency transponder 2. An Antenna is placed close to the rotary table so that when the transponder enters the working area of the antenna, the code that is written inside the transponder is read and is transmitted to a PC (using the serial Port). 3. A software is installed that, thanks to the code of each trasponder, search for the data pertinent to that particular mould and automatically transmit the data to all equipments. More precisely the transponder has the following characteristics: · It is a “read only” device constituted by a coil and a “chip”. · There is no battery, so the transponder is “forever”. · When the transponder enters the antenna working area, the antenna itself supply magnetic field that energizes the transponder. The transponder transmit a 64 bit data-stream. · The identification number which is inside the transponder is exclusive and is printed via laser during the manufacturing process. There is no possibility of changing this code in the future. · The transponder can work within the following temperature range: -35°C / +180 °C · It is PU, oil, water DMF, etc. resistant · It can be easily fixed to the mould with a M8 screw and can afford all the shocks that a mould can have the during PU soles production process. · The transponder is indifferent to rubbish, PU pieces, etc. that can remain attached to its surface.
The antenna
is placed close to the rotary table in a position that is before all the
equipments that must be reprogrammed when a mould is substituted. · Every time the rotary table makes one “index” presenting one new station in front of the antenna, the software carries the following activities: 1. It checks if the code of the “transponder” coming from the antenna for that particular station is exactly the same it was stored always for that station but at the previous round. It the two codes are exactly the same, no modification is accomplished. 2. If the two codes are different, the software searches its database for all the data associated with the code of the transponder just transmitted. 3. If there is no record associated with the code just transmitted, (and therefore the mould HAS NOT been in production before), default values are transmitted for the new mould. 4. If the record associated with the code exists, (and therefore the mould HAS been in production before), all the data concerning production, associated with that particular station, can be potentially transmitted to all the machines that must be re-programmed when a mould is substituted. The software allows to displays, modify and store all the data associated with each mould.
OFFICE FLOOR
material distribution on the rotary table Since the software automatically recognises when a mould has been substituted, it is created a file in which are automatically registered: 1) Time and date in which the mould was inserted in production 2) Time and date in which the mould left the production 3) Number of rounds of the rotary table in which the mould was inserted in production 4) Number of rounds of the rotary table in which the mould left the production 5) REAL number of soles produced for each mould 6) REAL numbers of soles produces for each article 7) Real number of soles produced for each shift.
All the data are saved in a “ACCESS” file (or “EXCEL” file) so that they be easily used for other purposes.
It is showed a graph in which it is recorded the speed of the rotary table during the 24 hours. This graph prevents that during the night the rotary table can be stopped for a certain time (for a rest) and then accelerated in order to achieve the expected production. From this graph you can read if and when the rotary table has been stopped (for example for cleaning the nozzle).
It is possible to connect all the PC in Ethernet Lan so that from the office they can “see” ON-LINE the REAL number of soles produced for each article.
If the planning office can supply a file in which there is written the list of the moulds that are supposed to be changed, it is possible to show directly on the PC at factory floor when is the proper moment for substituting the mould, (informing the operator 5 rounds before).
CENTRALIZED SYSTEM It is possible to have a centralized PC which is placed in laboratory (or in the office) in which all the data can be programmed BEFORE the moulds enters in production. This PC has its own antenna. All the production data are automatically transmitted to all PC at factory floor. In this way the mould is “already” programmed also the first time it enters in production, reducing waste of time and possibility of making mistake.
MORE PRECISELY:
The transponder DOES NOT contain ANY information regarding the mould.The transponder has only one code: an exclusive hexadecimal number. No other
transponder can have the same code.
0100A1B8F1
ALL INFORMATIONS ARE "INSIDE THE PC".
Code of
trasponder 0100A1B8F1 0100A1C02F
0100A1D960
The above mentioned data can be associated to the transponder in a
"permanent" way. We will call them "Permanent Data" . (We can imagine that
they "travel together with the transponder"). Obviously the value of each
"permanent data" can be modified.
AUTEC software can know the "Dynamic Data" only if it is created
an INTERFACE FILE (usually a TXT file) between our software and your ERP
software for production planning and control. In this text file, the list of
mould changing planning must be listed, for each rotary table and for each
station.When a mould is substituted (for ex. rotary table 3 station number 12) and
enters a new mould, the antenna reads the new code (for example: 0100A1B8F1)
and sends the code to the AUTEC PC. In every moment the PC knows which the
station in front of the antenna is. So the PC recognizes that in station
number 12 there is a new mould (and knows its article and size).
The AUTEC software CHECKS that new mould that enters the production is
exactly the article and size planned by your ERP software. If that does not
happen, a warning will be displayed for the operator. Question: Can the operator that works at the rotary table change the data in the planning office? Answer: Absolutely NO. The operator can access only certain area files protected by password. In any case he will never access the office area. (There is an INTERFACE FILE between the 2 areas). Question: Suppose that for a particular mould is expected a production of 200 pieces. After 150 rounds, because of an emergency, the mould is substituted with the mould related to emergency. After the emergency is finished, the original mould comes back. How does the AUTEC software react? If an urgent order enters that it is not the planned (and is not present in the INTERFACE FILE), the AUTEC software does not know anything about Colour and Material. The AUTEC software PRESUMES that Colour and Material remain the same as before. (We presume that if there is an urgent order, you place the mould in a rotary table where the Colour and Material is already present). At this point AUTEC software has ALL the necessary information and transmits them to the rotary table. When the urgent order is completed, AUTEC software recognizes the is entering once again the mould whose order was not completed and starts counting the soles from the point it was interrupted. Question: Suppose that for a particular station (For ex. 34) is expected a production of 300 pieces. While producing we realize that we have 20 rejects. How can I act with AUTEC software? Answer: It is possible to change in AUTEC PC the number of soles to be produced( updating from 300 to 320). After 315 rounds a warning will appear in PC display: "Attention after 5 round you have to substitute the mould in station number 34 with mould.... (Article and size)." After 316 rounds a warning will appear in PC display: "Attention after 4 round you have to substitute the mould in station number 34 with mould.... (Article and size)." ........... ........... After 320 rounds a warning will appear in PC display: "Attention now is the right moment for substituting the mould in station number 34 with mould.... (Article and size)." Question: Once the orders that have been introduced in the planning software ,Have I to digitize one more time in AUTEC software? Answer: NO. You will keep on working with your ERP software for production planning and control. An INTERFACE FILE must be created and it will not be necessary to double entry of orders. Question: Is there a graph that shows the “Speed” of the rotary table during the 24 hours? How does it work? Answer: YES. The graph that records the "speed" of rotary table works in this way: The system calculates the time in seconds that station number 1 takes for passing in front of the antenna. This value is continuously updated in a register. The PC reads this value all day long and shows it on a graph. The X axis represent the 24 hours of the day. The Y axis represents the value read in the register (the "speed" of rotary table expressed in seconds). If the rotary table should turn always at the same "speed" (for example: 200 seconds), we would obtain a straight line parallel to X axis (at the Y value of 200). Imagine that at 4 o'clock the rotary table was stopped for 1200 seconds (20 minutes). In the graph at X value of 4, you would notice a peak of 1200 seconds. In summary, in this graph you can read WHEN the rotary table stopped and HOW LONG it stopped. Question: The slope of mould carrier is a very important data. Can this data be integrated in AUTEC software? Answer: YES. We have a manipulator for automatic detection of mould carrier slope. The idea is the following: If a mould has worked for a long time without producing rejects, why should I change the slope the next time it enters in production? If I change the slope, maybe I really make rejects. The most important part of this device is a slide pneumatically moved that touches the mould-carrier with a little regulated pressure. This slide moves a position transducer. In the moment in which the slide touches the mould-carrier a measure is detected and stored. This measure is related to the mould-carrier tilting. The operation is repeated every time the rotary table makes one index. http://www.autecautomation.com/Video/sens_altezza.zip This manipulator has several purposes:
This last function is completely integrated with the automatic mould identification system. The software stores the slope at which the mould worked during the last time the mould was in production When the same mould comes back in production, the system checks if the mould slope is the same as it was. (obviously within a certain range: usually 7mm). If the slope is out of expected range, the demoulding robot and brush robot do not work, the AUTEC software warns about the situation and suggest of how many millimetre the operator is supposed to correct. At this point there are 2 possibilities:
Question: Is it possible to program the data of a mould before it enters into production? Answer: YES. AUTEC has developed a STATION FOR DETECTING THE QUOTES OF THE MOULD http://www.autecautomation.com/Video/Tastatore.zip The aim of this station is the following: to be able to detect all the geometrical data of the mould before it runs in production and transmit these data to all robots. In particular are automatically programmed: · The data of robot for extracting soles · The data of the trajectory that the brush has to follow This station consists of a plane where the mould is fixed in a referred way. The terminal part of the probe is moved by the operator in the point whose quotes we want to detect. A button is pushed in order to confirm and the 3 quotes are recorded in the memory of PC. This procedure is repeated for all points that we want to detect. The data are then elaborated by PC. This operation must be executed before the mould enters in production.
Question: How is possible to store the data of the mould before in enters into production, if we don’t know the slope of the mould carrier that will be set? Answer: We would like to point out that the data are detected while the mould is over the plane of this station in HORIZONTAL position. In relation with the tilting of the mould carrier in production, automatically detected by tilting sensor, the new paths that the robot has to follow are automatically calculated (for the extracting robot, the robot for applying the releasing agent/or brush robot). All these operations are automatically performed without any intervention from the operator that in this way is free of changing the tilting of the mould whenever he wants.
This station is composed of: 1. Basement The basement is made of aluminium profile. This basement has a horizontal plane over which the operator has to lay the mould. This basement also holds the manipulator that detects the tilting of the mould. 2. Device for detecting the 3 quotes. Device with 3 slides disposed in perpendicular way according to the 3 axis X, Y, Z. 3 potentiometers are rigidly connected with these slides and are interfaced with an analog to digital converter board. The strokes of each axis are: axis X=350 mm; axis Y=150 mm; axis Z = 150 mm.
This station is very important if you are producing soles with "compact islands". In this case you save time in programming the pouring head.
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