WO2019197970A1

WO2019197970A1 - Apparatus for molding plastics, rubber and metals, with telemetric control

Info

Publication number: WO2019197970A1
Application number: PCT/IB2019/052876
Authority: WO
Inventors: Virginio TARTAGLINO; Laura TARTAGLINO
Original assignee: Mycros S.R.L.
Priority date: 2018-04-12
Filing date: 2019-04-08
Publication date: 2019-10-17

Abstract

It is described an apparatus (1) for monitoring and controlling the molding of plastic materials, rubber and metals, comprising at least one molding apparatus (2) which is provided with a mold (9). Said apparatus (1) further comprises a communication network (3) with LPWAN technology, at least one node (4) of said communication network (3), a server (5), at least one remote application (6) connected to said server (5), and at least one sensor (11) associated with the mold (9) and adapted to exchange information with said server (5) through said at least one node (4).

Description

“Apparatus for molding plastics, rubber and metals, with telemetric control”

The present invention relates to an apparatus for molding plastic materials, rubber and metals with telemetric control.

“Metal molding” means the use of molds for metal working in general, by casting, shearing, bending, deformation, bending, die-casting, drawing, foaming or sintering.

The molding industry uses expensive molding machines and plants (from€ 100,000 to€ 1,000,000) and equally expensive molds, of significant number in the order of tens of thousands (at least one mold for each object to manufacture).

Systems for monitoring and controlling the production of such plants are increasingly required.

With regard to presses, the manufacturing data monitoring systems currently adopted on molding machines and plants adopt a series of sensors conveniently placed aboard the press which connect to the PLCs of the press itself; they normally require a wiring between machine and company control system; alternatively, communication methods based on WiFi or Bluetooth, RFID are used, with the known limitations, such as: short distance covered by the signal, need for multiple access points, routers or various repeaters, instability of communications.

In any case, both methods require a company network infrastructure to be built in the production departments where the machines to be monitored are present, with significant economic burden and interferences with the operating flow.

With regard to the tools used on presses, among which are molds, generally there is no control whatsoever nor is there any trace of use or maintenance performed or to be performed, of their availability or even of their location (company warehouse or at the manufacturer for periodical or emergency maintenance). Some attempts were made with RFID devices but they are costly and ineffective in normal operating situations present in molding manufacturing plants.

After all, directly monitoring a mold, which is an inherently movable or portable tool, is rather complex; consequently, most of the time, the idea of monitoring and controlling tools such as molds (or other important and costly movable devices) is abandoned for technical difficulties or for excessive costs, thus surrendering the possibility of knowing the limits of efficiency of one’s tools and often sustaining additional costs for unexpected operations.

Telemetry (remote monitoring) systems of movable and/or portable objects are known, which adopt a communication network between sensors and network nodes (gateways) using a protocol called LoRaWAN (Long Range Wide Area Network) at 868/915/434 MHz.

The sensors of said systems have low energy consumption, in which the batteries can last, according to usage and transmission frequency, even for thousands of messages or several years; they are small in size (as big as a USB flash drive) and low in weight (approximately 5 grams).

The communication network, either private or public, includes gateways designed to use the LoRaWAN protocol.

The gateways can also act as concentrators with data storage and, where possible, can be configured to relaunch data to a cloud in aggregated and programmed form. This implies cost-effectiveness in outbound traffic management and in the construction of the gateway itself.

The LoRaWAN protocol has low battery consumption and protected data transmission (by virtue of AES-128 encryption).

The communication range is about 2 km in high population density areas and extends to 15 km in open field, also influenced by the mutual position of sensor and gateway; if the gateway is installed in an elevated position, the radius will be greater than that of a gateway installed at road level. LoRaWAN is part of a category of technologies called LPWAN, meaning Low Power Wide Area Network; this technology was developed in order to allow battery-powered sensors to send and receive messages, using the least amount of energy possible to preserve the battery.

LPWAN technology uses the same frequencies mentioned above

(868/915/434 MHz) but with different modulation and communication protocols. LoRaWAN is an example of said protocols.

KR-101842372 describes a remote-control system of a molding machine comprising a sensor module for collecting molding information.

US-2012/0231103 describes a counting system of the cycles of a mold by means of wired sensors temporarily associated with the mold only at the production stage.

It is an object of the present invention to provide an apparatus for molding plastic materials, rubber and metals, in which the molds are efficiently and continuously monitored.

It is a further object of the present invention that said monitoring is cost-effective and does not imply significant changes to a company network.

It is a yet further object of the present invention that said apparatus allows the monitoring also of the presses.

According to the invention, said and further objects are achieved by a molding apparatus as defined in claim 1.

Advantageously, a complete control of one or more apparatuses of a company in one or more production plants can be achieved.

The same information can be made available both to the company which uses the apparatuses to control and improve department efficiency and to the mold (and possibly the press) manufacturer for maintenance.

An immediate interaction between user and designer/manufacturer is obtained.

These and other features of the present invention will be more apparent from the following detailed description of a practical embodiment thereof, shown by way of non-limiting example in the accompanying drawings, in which:

figure 1 shows a diagram of an apparatus according to the present invention;

figure 2 shows a schematic side view of a molding apparatus;

figure 3 shows a schematic side view of a pressure die-casting molding apparatus on horizontal press;

figure 4 shows a schematic side view of a pressure die-casting molding apparatus on vertical press;

figure 5 shows a front view of a mold;

figure 6 shows a schematic side view of a vertical compression molding apparatus.

An apparatus 1 for monitoring and controlling the molding of plastic materials, rubber and metals comprises a plurality of molding apparatuses 2, a communication network 3 with LoRaWAN protocol, nodes (gateways) 4 adapted to concentrate signals coming from apparatuses 2, a server 5 adapted to receive signals from said nodes 4, and a plurality of remote application servers 6 connected to said server 5 through a secure network 7 (e.g. an SSL TCP/IP network).

Each apparatus 2 comprises a press 8 and a mold 9 removably associated with the press 8.

The mold 9 is separably associated with a sensor device 11 (henceforth simply sensor 11 for convenience) adapted to transmit information to the server 5 through a node 4.

A sensor 11, which is distinct and independent from the sensor 11 of the mold 9, may be removably associated with the press 8.

The mold 9 comprises a movable part 91 and a fixed part (punch) 10. The movable part 91 of the mold 9 is separably coupled to a movable portion 81 of the press 8, while the punch 10 is separably coupled to a fixed part 82 of the press 8. The sensor 11 is preferably associated with the movable part 91 of the mold 9, possibly also to the punch.

Additionally, a sensor 11 can be associated with the movable part 81 of the press 8, and possibly also with the fixed part 82 of the press 8.

In any case, distinct and independent sensors 11 are fixed to the movable part 91 of the mold 9, to the punch 10, to the movable part 81 of the press 8 and to the fixed part 82 of the press 8.

Figure 3 shows a pressure die-casting molding apparatus 2 (valid for any type of material, plastic, rubber or metal) wherein the movable part 81 of the machine 8 and the movable part 91 of the mold 9 move horizontally.

This embodiment also shows an injection screw cylinder 23, a hopper 25, extracting means 42, a sliding guide 26 and hot runner means 41. Figure 5 shows blocks 44 (interchangeable), in addition to the carriages 43 of the mold 9. A sensor 11 can be applied to one or more of said components.

Similar components are found in the apparatus 2 of figure 4, wherein the movable parts move in a vertical direction.

The apparatus 2 in figure 6 additionally shows dies 45 and a workpiece 50, it being also possible to install a sensor 11, as well as ejection means 46, on the dies 45.

The apparatus 1 may have a single apparatus 2 which interfaces with a single node 4 connected to the server 5.

The sensors 11 have the following characteristics:

they consist of an electronic card with the printed circuit onto which various components with various features are fixed; - they can be installed in origin by the manufacturer (tool maker) or even later by the final user (molder);

they do not require any fixed power supply because they use 1.2-5V batteries;

they have a long battery life because they use LPWAN (Low Power Wide Area Network) technology to communicate with the respective gateways 4;

they are normally of the disposable type except for the ones provided with rechargeable battery;

they can be activated and deactivated either on-site or remotely;

they are remotely programmable and configurable.

The sensors 11 have indicative dimensions of 20 mm x 60 mm x 8 mm, and a weight of about 5 grams, comprising standard incorporated battery.

The configurable standard features are:

on/off: through button;

geolocation: LoRaWAN Geolocation;

accelerometer: range up to l6g;

operating signal: with blue and red color flashing LED;

- communication: LoRaWAN 868/915/434 MHz Protocol or alternative LPWAN technology protocol;

battery: 3.6V l50mAh;

capacitance proximity: sensor tamper protection, recognizes if the device is integral with the mold or has been dissociated therefrom.

The batteries of the sensor 11 may be rechargeable or non- rechargeable.

Various autonomous power supply means (again without wiring) can be provided for recharging the batteries, such as a magnetic induction device to convert kinetic energy into electrical energy or photovoltaic, piezoelectric, pyroelectric, thermoelectric, electrostatic capacitive means.

The sensors 11 allow the following specific configurable functions: storage: progressive movements counting;

timer: for programming sending of messages;

working temperature: e.g. from -20°C to +60°C; angular orientation: pitch -180° + 180°, Roll -90° + 90°;

drop: vertical/horizontal or vice versa.

The sensors 11 installed on the molds 9 must always be activated to ensure the geolocation control (e.g. transport to the maintenance workshop or positioning in the mold warehouse) and self-diagnostics (e.g. battery charge level, operating temperature, comparison of molding times, etc.) as well.

The following are detected through the described sensors 11 installed on the apparatus 2:

- the active/inactive status of the mold 9 starting from a default date;

possible movements for the preparation of the apparatus 2; productive activity by counting the cycles and their progressive number;

- actual working and inactivity times;

confirmation of performed maintenance;

the total working time for each molding cycle;

the partial working time for each cycle (approach, closing, opening, extracting);

- unproductive downtime;

mold opening and closing accelerations;

environmental vibrations beyond the predetermined threshold during the opening/closing stages of the mold or during molding;

- working temperature of the sensor;

battery voltage level;

transmission signal power;

mold status: parking, production (molding movements), transfer movement (different from molding movements).

The sensor device 11 basically comprises a plurality of elements, such as sensors of various type, batteries, antenna, modem, etc.

All the data collected from the field are transferred in real time to the server 5 on which is stored the complete registration data of each single component of the apparatus 2 is stored, comprising other information deemed useful such as:

construction characteristics, constraints and restrictions of use of the molds 9 on the presses 8;

parts to be made for which it was designed and production rates;

- duration of the manufacturer’s warranties;

assembly drawings and drawings of spare parts and consumables;

electrical and mechanical devices, miscellaneous equipment; multimedia type files, including films (disassembly, assembly) audio notes, photographs or images from design systems

(CAD);

set-up and production parameter plans;

preventive maintenance plans;

rules of conduct for purposes of safety of personnel, assets and environment;

productions made, preventive and predictive maintenance planning.

In this manner, a profile of the mold 9, which is full of information and which will replace the normal paper archives (when existing) and will follow it throughout its life, can be made; the database can be easily accessed via web from fixed stations or mobile devices to access all the information linked to the complete registration data of the mold 9 and to interact with sufficient rapidity and simplicity for any activity related to the mold 9.

Of particular importance is the exchange of information with the operators aboard the machine through the HMI, both for transferring set-up and environmental safety behavior information, and for detecting further information, such as: the product being worked, performed quality controls, any rejects and respective descriptions, reasons for machine stops, etc.

Advantageously, the sensor 11 allows a two-way transmission of information, i.e. it can transmit and receive information from the system between the user parameters needed to change the data acquisition or transmission methods according to operating and environmental situations.

It is further possible to examine the collected information which, conveniently processed on demand, can offer structured data, such as:

history of use of the mold 9, productions made and detected times;

productive efficiency of the mold 9 by comparing production rates and theoretical times with the actual ones;

- performed maintenance history;

schedules for programmed maintenance operations.

Finally, on the basis of the actual trend, which can be compared with the production parameters prescribed for the apparatus 2, of the hours of actual use, of the qualitative variation of the molded products (where available), it is possible to review and better define the predictive and proactive maintenance plans or send alarms to the operator to modify the machine setup parameters.

The sensor device 11 is adapted to process the data and send alerts and alarms to require preventive and predictive maintenance.

More in particular, the sensor device 11 :

- processes the detected cycle progression data in comparison with the data predetermined by the manufacturer for preventive maintenance frequencies, sending alerts and alarms to the operators to activate the required operations, in order to ensure the integrity of the mold 9;

- processes the detected process technological data (operating temperature, vibration level) in comparison with the data predetermined by the manufacturer, determining the significant parameter variations and sending warnings and alerts operators to overcome critical thresholds, in order to ensure the integrity of the mold 9.

The same considerations and processing can be performed for the presses 8 coupled to said molds 9.

The sensors 11 are further adapted to progressively count the movements of the monitored objects.

The progressive counting function has the peculiarity of allowing the transmission of the movement data not only upon the occurrence of each single motion event but, according to the set configuration, of transmitting the data in aggregated and programmed form (e.g. every hour or when a given number of detected movements is reached), whereby reducing data traffic, line congestion and saving on operating costs.

Even more important is the progressive counter which allows, where the application on objects or tools so requires, ensuring that some individual movements are not occasionally lost, because the transmission of the progressive numbers absorbs, for its very nature, possible temporary communication shortcomings of the network between sensors and gateways which could cause the loss of some events.

One example for all is that of the sensor 11 applied to a mold 9 with the function of counting the strikes produced during the steps of molding; it is apparent that occasionally not signaled strikes would affect the quality of production determinations, and consequently of efficiency data, the counts of the materials used, the request for maintenance operations, and so on.

The cycle count is performed by the accelerometer of the three-axis, low-consumption type (e.g. Bosch BMA250E).

The molding time is the most significant, e.g. 17” on the total 20” of the cycle: therefore, all other operations occur in the remaining 3”; the activity of sensor 11 to acquire the number of molding cycles is concentrated in this residual time. During the step of closing, the sensor 11, integral with the movable part 91 of the mold 9, detects the acceleration movement in departure and deceleration movement upon arrival; the same occurs during the step of opening; there will be a total of at least four movements for each cycle (except for additional movements due to stops along the opening/closing paths, vibrations, etc.).

In terms of firmware of the sensor 11, on the basis of the parameters set on the sensor 11 concerning the“Accelerometer sensitivity threshold” and the“Reference Axis X, Y or Z”, the processor selects the acceleration or deceleration set as the most significant (preferably the opening acceleration) from said four described movements, then blacks-out the activity of the accelerometer and the acquisition of other movements, for a time sufficient to complete the cycle (defined in the“Accelerometer blackout timer” user parameter), in order to prevent the acquisition of improper or spurious signals or rebounds due to vibrations or other. Then, the accelerometer is put back on alert to repeat the cycle acquisition operation.

Before considering the acquired“cycle completed” signal as valid, the sensor 11 compares the detected cycle times with those provided in the set parameters, such as“Total molding cycle time” and“Mold opening and closing step time”: if the detected value falls within a predetermined range, then the cycle count is validated and the progressive cycle counter is updated.

A self-learning function is provided in the firmware to automatically set some user parameters; in particular, the sensitivity threshold on which it is based the acquisition of the movement: movements could be lost if the threshold were too high, there would be excessive movements during the same cycle if it were too low; in both cases, an incorrect cycle count would occur. Consequently, an“excellent” threshold must be identified on which to base the cycle count in a secure and reliable manner.

The self-learning function takes place with the following method: - upon first installation of the mold 9 on the press 8, the sensor 11 records a predetermined sequence of movements positioning itself on an initial threshold of sensitivity (e.g. 10 on a scale from 0 to 255) by checking whether the performed cycles fall within the interval of time entered in the parameters; it then moves to a higher threshold (e.g. 15) and the recording and control is repeated; and so forth for a predefined number of times;

- at the end, it processes the data and selects according to an algorithm the range of thresholds within which the data are complete and consistent (e.g. between 15 and 20);

- the first movement of the cycle which entirely falls within or exceeds the threshold will be the useful one for the cycle count, while the subsequent movements will be blacked out (for the blackout timer indicated in the Parameters, and will not be recorded in the sensor until the next cycle).

The operation is repeated automatically if the batteries are replaced or if the“Reset” button is pressed.

The sensor device 11 can perform all the functions described only with the accelerometer.

The sensors 11 in the project can be used directly on the objects to be monitored by means of traditional fixing systems, such as screws, double- sided adhesive tape, magnetic holder, straps, etc.

For some molds 9, according to the working conditions in which the sensor 11 and the mold 9 to be monitored itself operate (e.g. extreme temperatures beyond the range -20°C + 60°C), the use of a support or shell is provided, with functions of isolation from the object and resistance to high temperatures up to +200°C or in special cases up to +400°C.

In such cases, the support may also contain auxiliary disposable batteries or 5V batteries rechargeable via micro USB. They are fixed simply with two screws.

The support is such as to allow the cooling thereof by natural ventilation, containing the sensor, avoiding availability of the on/off button to prevent involuntary change of status, not interfering with the normal molding functions, not interfering during the steps of preparing and of tooling of the machine 8.

The support is provided for a mechanical fastening by means of two screws and can be embedded in a special niche to be made during the step of construction on the mold 9 itself in order to avoid interference during the steps of handling and transporting.

As mentioned, the sensors 11 can also be used on the presses 8 with the purpose of having continuous control and full use of the apparatus 2; although adding the productions detected by the mold 9 used on the machine

8 would provide the total production count, molds 9 which are not monitored may be present and consequently part of the actual production could be lost.

Information gathering methods are known according to the recommendations of EUROMAP (European Plastic and Rubber Machinery

Industry), an association which represents over 1000 manufacturers of equipment for plastic and rubber industries.

The EUROMAP recommendations considered here are those relating to the exchange of data for external equipment management, e.g. molded product picking robots; the most recent is EUROMAP 78 which indicates a multipolar pin/socket connector as the physical port to be used indicating the communication protocols to use. This recommendation applies to all machines currently used by molding companies.

EUROMAP Recommendation 83 was emitted (during final release) for machines with PLC, which provides the direct communication with the

PLC through a specific and uniform OPC UA protocol for all the entire press world. OPC UA is recognized worldwide as a standard communication protocol between machines for Industry 4.0.

In accordance with the present invention, the apparatus 1 for the acquisition of the information from the machine 8 includes: for EUROMAP 78, the installation of a multipolar connector which acts as a switch between the connector of the press 8 and that of the external robot, without interfering with the features present in the connectors themselves;

- for EUROMAP 83, the installation of a connection board to the

PLC, conveniently programmed to acquire all the required data from the telemetry device.

The board may in any case capture data from PLC also through other standard or proprietary protocols which may be used or suggested by the manufacturers of presses.

The apparatus 1 provides the application of a sensor 11 to the press 8 to transfer the data acquired by the press 8 to the server 5, whereby avoiding further infrastructures and invasive installations in the department and on presses themselves.

The monitoring of the presses 8 allows collecting not only the cycle count products (as required for the mold 9), but also of all the process data of the operation of the press 8, such as, by way of non-exhaustive example, closing, injection, opening times, operating temperatures, operating pressures, alarms, etc.

A full control of the production of the apparatus 2, comprising mold 9 and press 8, is thus obtained.

The LoRaWAN protocol uses three different classes of devices: Class A, Class B, Class C.

Sensors 11 are in Classes A and C.

Advantageously, the apparatus 1 constantly monitors the productive development of the mold 9 and the presses 8 where they are installed, verifying in real time production efficiency with respect to the parameters provided by manufacturers, monitoring the use of the molds 9 and of the presses 8 in relation to the available time, signaling in advance scheduled maintenance operations, evaluated on the basis of the overall efficiency of the apparatus 2 the need for predictive or proactive maintenance operations.

The activation of the function requires just one login to one portal.

After a few moments, the apparatus 1 is operational and usable.

The univocal code of the sensor 11 with the code of the element with which it is associated and its initial location is associated in said portal. The registration data allows entering much more information (manufacturer, installation, warranties, etc.) which may be useful in this context or relevant for other activities.

The LoRaWAN protocol facilitates the application of the apparatus 1 in companies applying the described sensors 11 without creating any infrastructure and without installing other devices or gateways in the site where the objects to be monitored are placed.

Advantageously, it is possible to obtain a complete control of one or more devices 2 of a company in one or more production plants.

The same information can be made available both to the company that uses the apparatus 2 to check and improve department efficiency and to the manufacturer of the mold 2 or of the press 8, which most of the times do not know how components they designed and made are used and often must bear the burden of maintenance on behalf of the customer.

This allows an interaction between user and designer/manufacturer immediately without having to pass through the production of paper or exchange of email which in all cases requires some time.

The apparatus 1 may comprise HMI modules for managing information and using alerts or warning according to productivity and efficiency detected in real time and compared with the expected standards or historical averages, also aboard the apparatus 2.

In such case, a stable connection to the database via Ethernet is required.

Operators aboard the machine can integrate the detected information with those for which they are responsible, such as: operator code, job being worked, batch of materials used, production batch, machine stop descriptions, produced quality levels or compilation of quality control plans.

Finally, the application is provided to be connected to the ERP system for exchanging information relating to production orders, raw materials, progress and entry into production, etc.

Touchscreen devices, either both fixed or movable aboard the machine, must be provided for the HMI.

Applying specific sensors 11 which detect the passage of current or the on/off status, it is also possible to check the actual availability and the use of presses 8 on which the molds 9 are fitted, whereby completing the information flow to all company assets involved in the molding process.

A possible alternative to LPWAN technology, again for long range communications, is a similar technology available in some countries but not yet in Italy called Narrow Band technology; this is also based on 868 MHz frequencies but limited to given specific bands reserved for IoT (Internet of

Things). It uses next-generation mobile telephone cellular networks and therefore requires a dedicated 5G SIM to be installed on the sensor.

Claims

1. An apparatus (1) for monitoring and controlling the molding of plastic materials, rubber and metals, comprising at least one molding apparatus (2) which is provided with a mold (9), a communication network (3), at least one node (4) of said communication network (3), a server (5), at least one remote application (6) connected to said server (5), and at least one sensor device (11) associated with the mold (9) and adapted to exchange information with said server (5) through said at least one node (4),

characterized in that

said communication network (3) implements LPWAN technology, said sensor device (11) is integral with the mold (9) throughout the life of the mold (9), and is equipped with battery and geolocation means.

2. An apparatus (1) according to claim 1, characterized in that the sensor device (11) comprises an accelerometer adapted to the count of the cycles of the mold (9).

3. An apparatus (1) according to claim 2, characterized in that the accelerometer is adapted to geolocate the sensor device (11).

4. An apparatus (1) according to claim 3, characterized in that the accelerometer is the only sensor of the sensor device (11) which performs cycle counting, geolocation and extra production movement status functions.

5. An apparatus (1) according to any one of the preceding claims, characterized in that the sensor device (11) is integral with a movable part (91) of the mold (9).

6. An apparatus (1) according to any one of the preceding claims, characterized in that the sensor device (11) is adapted to process data and send alerts and alarms to require preventive and predictive maintenance.

7. An apparatus (1) according to claim 6, characterized in that the sensor device (11):

- processes the detected cycle progression data in comparison with the data predetermined by the manufacturer for preventive maintenance frequencies, sending alerts and alarms to the operators to activate the required operations, in order to ensure the integrity of the mold (9);

- processes the detected process technological data (working temperature, vibration level) in comparison with the data predetermined by the manufacturer, determining the significant parameter variations and sending warnings and alerts operators to overcome critical thresholds, in order to ensure the integrity of the mold (9).

8. An apparatus (1) according to any one of the preceding claims, characterized in that the communication network (3) uses the LoRaWAN protocol.

9. A method for counting the working cycles of a mold (9) of an apparatus (1) according to any one of the preceding claims, characterized in that it provides the selection by means of an accelerometer of one of the four accelerations/decelerations to which a movable part (91) of the mold (9) is subjected in the step of closing/opening, whereby blacking out the accelerometer for a time sufficient to complete a cycle.

10. A method according to claim 9, characterized in that the cycle count is performed by setting a sensitivity threshold of the accelerometer as follows:

- upon first installation of the mold (9) on a press (8), the sensor device

(11) records a predetermined sequence of movements positioning itself on an initial sensitivity threshold, whereby verifying whether the performed cycles fall within an interval of time entered in the parameters; it then moves to a higher threshold and the recording and control is repeated for a predefined number of times;

- at the end, the data is processed and the range of thresholds within which the data are complete and consistent are selected according to an algorithm;

- the first movement of the cycle which entirely falls within or exceeds the threshold will be the useful one for the cycle count, while the subsequent movements will be blacked out.