Temperature sensing smart label

Abstract

The present application describes an integrated autonomous temperature smart label engineered to allow the continuous monitorization of temperature gradients in fluid hoses where applied, identifying and signaling potential risk scenarios. The proposed device (100) for monitoring the surface temperature of rubber-based products (10) is characterized by comprising a temperature sensor; a control board; and a thermoelectric generator.

Description

[0001] DESCRIPTION

[0002] " TEMPERATURE SENSING SMART LABEL"

[0003] Technical Field

[0004] The present application describes an integrated autonomous temperature smart label engineered to allow the continuous monitori zation of temperature gradients in fluid hoses where applied, identi fying and signalling potential risk scenarios .

[0005] Background art

[0006] Most of known technology in the smart temperature labels is used in the packaging of perishable products , and particularly used in the transport of physical and chemical substances where monitoring of environmental conditions is a primordial need . Other technical fields mention the possibility of using of thermoelectric harvesters to supply electric energy to RFID tags , improving their li fetime .

[0007] For example , US2015317896A1 describes a smart label that includes an antenna and an integrated sensor which provides data generated in response to an environmental parameter , such as temperature , moisture , light , etc . The smart label operates with RFID communication to reduce costs .

[0008] In addition, US7675424B2 proposes an invention which comprises , in a label for perishable items , an improvement comprising an electronic circuit including means for performing time-temperature integration ( TTI ) indicating that time and / or temperature levels reached may compromise the quality or shel f li fe of the item to which the label is af fixed to . The label may be used on a wide variety of products that require careful handling in terms of temperature and / or time elapsed before use , such as fresh or frozen foods , meats , or even drugs , blood, and organs for organ transplant .

[0009] The present invention disclosure di f fers from the previously mentioned documents since it provides a new technical approach based on a textile autonomous temperature smart label configured to allow the continuous monitoring of the thermal conditions to which fluid hoses are submitted, applied for example in the transport / automotive sector , taking advantage of its thermal events to generate and harvest energy .

[0010] Summary

[0011] The present invention describes a device for monitoring the surface temperature of rubber-based products characteri zed by comprising a temperature sensor ; a control board; and a thermoelectric generator .

[0012] In a proposed embodiment of present invention, the control board is configured to acquire data from the temperature sensor .

[0013] Yet in another proposed embodiment of present invention, the data acquired from the temperature sensor comprises temperature values of the surface of the rubber-based product where applied .

[0014] Yet in another proposed embodiment of present invention, the temperature sensor comprises an arrangement of layers comprising at least one of a metal-based layer on top of a polymeric substrate , protected by a polymeric top layer .

[0015] Yet in another proposed embodiment of present invention, the control board comprises at least one of an energy harvesting module , energy storage module , sensor acquisition module and communication module .

[0016] Yet in another proposed embodiment of present invention, the thermoelectric generator comprises an arrangement of layers comprising at least one thermocouple comprising a n-type thermoelectric pellet and a p-type thermoelectric pellet electrically connected in series , arranged between top and bottom ceramic layers .

[0017] Yet in another proposed embodiment of present invention, the device further comprises a display device composed of an electronic control module and a set of at least three multisegment display .

[0018] Yet in another proposed embodiment of present invention, the display device is configured to provide visual information to a user, said visual information being provided by the control board .

[0019] Yet in another proposed embodiment of present invention, the device is integrated on the surface of a fluid hose through a compatible adhesive rubber-based material . General Description

[0020] The present invention describes an integrated autonomous temperature smart label configured to continuously monitor temperature gradients in fluid hoses where applied, identi fying and signalling potential risk scenarios .

[0021] The developed device is a textile , active , hybrid and modular smart label with sensing, energy harvesting and communication capabilities to apply to fluid hoses , and which is obtained through the application of textile processes and printed electronics .

[0022] The invention also considers the possibility of including an innovative approach for the displaying of the information gathered by the smart label , including the integration of a flexible informative display that will be coupled to the smart label and produced by printed electronic techniques .

[0023] The herein disclosed textile and printed temperature sensing smart labels , allow the wireless sensing of textile and rubber-based composites such as fluid hoses . The smart label also includes integrated thermoelectric harvesters , assuring the sel f-suf ficiency of the device .

[0024] In addition, the proposed textile temperature smart label is composed by di f ferent systems , namely temperature sensor, energy harvester, communication system and controlling electronics .

[0025] Brief description of the drawings

[0026] For better understanding of the present application, figures representing preferred embodiments are herein attached which, however, are not intended to limit the technique disclosed herein.

[0027] Fig. 1 - illustrates the proposed integration of the textile temperature sensing smart label on the rubber-based fluid hose. The reference letters are related to:

[0028] 10 - Fluid hose;

[0029] 100 - Textile-based temperature sensing smart label; 1011 - Heatsink.

[0030] Fig. 2 - illustrates a possible embodiment of a back view perspective of the developed textile temperature sensing smart label produced by the application of printed electronics. The reference letters are related to:

[0031] 101 - Thermoelectric generator;

[0032] 102 - Polyimide-based and flexible printed circuit board (PCB) laminated on a textile substrate.

[0033] Fig. 3 - illustrates a possible embodiment of a front view perspective of Polyimide-based and flexible printed circuit board laminated on a textile substrate (102) . The reference letters are related to:

[0034] 103 - Printed antenna;

[0035] 104 - Printed temperature sensor.

[0036] Fig. 4 - illustrates a possible embodiment of the proposed textile-based temperature sensing smart label (100) . The reference letters are related to:

[0037] 101 - Thermoelectric generator;

[0038] 102 - Polyimide-based and flexible printed circuit board (PCB) ;

[0039] 103 - Printed textile-based antenna;

[0040] 104 - Printed textile-based temperature sensor. Fig. 5 - illustrates a vertical cross-section of the multilayer electroluminescent structure (200) comprised by the printed flexible informative display. The reference letters are related to:

[0041] 201 - Flexible polymeric substrate;

[0042] 202 - Printed transparent conductive layer;

[0043] 203 - Printed electroluminescent layer;

[0044] 204 - Printed dielectric layer;

[0045] 205 - Printed conductive layer.

[0046] Description of Embodiments

[0047] With reference to the figures, some embodiments are now described in more detail, which are however not intended to limit the scope of the present application.

[0048] The present application describes a textile smart label (100) enabled with temperature sensing, energy harvesting and communication capabilities, which is obtained either by printing techniques or textile processes. In one of the possible embodiments of the present invention, the textile smart label (100) is integrated on the surface of a fluid hose (10) . The smart label (100) is constituted by a textile substrate with an integrated flexible printed circuit board (102) composed by the printed / textile devices and a thermoelectric generator (101) for energy harvesting. This thermoelectric generator (101) can be either a bulk or flexible film device. The electrical connections between the PCB (102) and the thermoelectric generator (101) are assembled directly onto the respective pads of the electronic circuitry. The dimensions of the generator (101) can be adjusted to increase or decrease the energy provided to the sensorial device, i.e., the set composed by the PCB (102) and the temperature sensor (104) , according to the expected temperature gradients.

[0049] In one of the proposed embodiments, the textile temperature smart label (100) may be obtained through production methods based on printed electronics. It is composed by a temperature sensor (104) and a Bluetooth antenna (103) directly printed onto a polyimide-based and flexible printed circuit board (102) . This substrate features a thickness of 50-75 pm, providing flexibility and conformability. Both the sensor (104) and antenna (103) are printed by resorting to conductive silver inks with different properties with a theoretical sheet resistance inferior to 10 mQ / sq / mil for the first case, and within a range between 10 mQ / sq / mil and 20 mQ / sq / mil for the latter. Both devices, the sensor (104) and antenna (103) , are printed through a screen-printing process over a 140x31 mesh (140 yarns / cm and 31 pm yarn diameter) . The mesh is based on a polymeric screen that allows the passage of the silver ink in a predefined pattern. This printing process is not limiting, as it can also be achieved resorting to the use of other existing techniques as inkjet, PVD or sputtering. After the deposition of ink with the defined pattern onto the end substrate, the films are cured in a thermal oven at an approximate temperature of 110°C, within a time interval of 10 to 20 minutes. As a thermal stabilization treatment, the printed devices (103, 104) are subjected to an annealing process at 200°C for approximately 2 hours. Furthermore, said printed devices (103, 104) are covered with an encapsulating layer, ensuring the necessary protection to external aggressions. The geometry of the sensor (103) can be dimensioned and adjusted according to the demands of the final layout, temperature sensing's resolution and / or sensitivity, and others. The printed antenna (103) possesses a geometry and effective length compatible with the respective Bluetooth frequency range. The overall structure of the antenna (103) can be adjusted to suit other frequencies of operation. A flexible battery is attached on the opposed surface of the circuitry of the PCB (102) . The electrical connections of all the printed devices are also printed directly onto the respective conductive pads, ensuring the correct connection to the remaining controlling electronics.

[0050] After comprising the elements that compose the final textile smart label (100) , its integration on the surface of the fluid hose (10) is achieved by two processes. The polyimide substrate is integrated in the textile substrate by resorting to an adhesive, with the printed devices and electronic circuitry oriented to the surface of the fluid hose (10) . The adhesive does not require any singular thermal or mechanical treatment, which simplifies the integration process. For the thermoelectric generator (101) , a mechanical support is attached around the fluid hose (10) where the thermoelectric generator (101) and a heat sink (1011) , located over the thermoelectric generator (101) , are placed, ensuring the necessary thermal contact on the interface between the fluid hose (10) surface and the bottom surface of the thermoelectric generator (101) , and the top surface of the generator (101) and the heat sink (1011) . The above-mentioned integration methods enable the correct positioning and fixation of the smart label elements onto the fluid hose (10) , without compromising the mechanical and electrical properties of both the functional devices and the hose (10) itself. Furthermore, the materials applied in this invention were specifically chosen in terms of mechanical, electrical, thermal, and chemical properties to ensure both the functionality of the solution but also its integrity in the final application environment. Mechanically, the solutions are flexible in nature, which guarantees the possibility of integration around the injection fluid hose (10) , except for the thermoelectric generator (101) , which in this case has a support designed for this application and allows its integration according to its operating needs.

[0051] From the thermal point of view, in the case of the temperature sensor (104) , it is composed of materials that allow heat conduction to the monitoring area. In the case of the electronic components themselves, their operating temperatures encompass the common temperature ranges of the application in question, and their performance is not affected by them. At this point the electrical issue can also come into play, which should not be compromised in the integration to the final product. The materials in use are capable of withstanding the environment in which they are inserted without neglecting their properties and integrity. In addition, the textile temperature smart label (100) also includes a complete textile version, that comprises a textile-based temperature sensor (104) and a Bluetooth antenna (103) directly connected to the circuit board (102) . This substrate features a thickness of 50-75 pm, providing flexibility and conformability. Both the sensor (104) and antenna (103) are embroidered using non-insulated nickel- based and insulated copper-based conductive yarns respectively, with a theoretical electrical resistance range between 78 and 93 Q / m for the first case, and inferior to 10 Q / m for the latter. Both devices (103, 104) are integrated into a single jersey textile structure through embroidered processes, namely cording process, which consists of fixing the conductive yarn straight through a zig-zag stitch. This process allows the integration of the conductive yarn according to the intended design considering the positioning of the different devices (temperature sensor (104) , antenna (103) , and PCB (102) ) . The textile structure consists of a knitted fabric composed by polyester fibres (PET) . As a resistive sensor, the selected yarn and sensor design provide an efficient sensor performance, achieving a very stable and linear variation of electrical resistance with temperature, exhibiting a sensitivity above 1 Q / °C. The geometry can be dimensioned and adjusted according to the demands of the final layout, temperature sensing's resolution and / or sensitivity, and others. The textile antenna (103) possesses a geometry and effective length compatible with the respective Bluetooth frequency range. The antenna (103) is integrated exhibiting a length of 32 mm and a width of 5.5 mm. The overall structure of the antenna (103) can be adjusted to suit other frequencies of operation.

[0052] The final printed circuit board (102) is attached to the single jersey substrate by sewing the PCB ends, where the textile temperature sensor (102) and the textile antenna

[0053] (103) are integrated as well. The textile temperature sensor

[0054] (104) is connected to the PCB (102) through a mechanical connection, where the conductive yarn passes successively through a conductive eyelet providing the required electrical contact. On the other hand, the textile temperature sensor (104) is connected to the PCB (102) using a conventional soldering process. A flexible battery is attached on the opposed surface of the circuitry.

[0055] Concerning the overall functionality of the printed circuit board (102) included in the smart label (100) , it can be divided in four modules, namely an energy harvesting module, an energy storage module, a sensor acquisition module and a communication module. The energy storage module is responsible for storing the harvested electrical energy generated in the energy harvesting module by the thermoelectric generator (101) , due to the thermal gradient between the surface of the fluid hose (10) and the surroundings. The harvested energy is stored in a miniaturized battery that is also responsible for backup powering the remaining systems of the label (100) . One of said remaining systems is the sensor acquisition module which is constituted by the temperature sensor (104) and the required electronic components. The data therein collected by the sensor (104) is recorded and processed by the electronic components, and then sent to a receiving unit, for example, a flexible informative display (200) by means of a communication system module, based on a wireless Bluetooth protocol.

[0056] With the integration of this smart label (100) solution, either of printed nature or textile-based, the monitoring of the temperature at the surface of the fluid hose (10) can be achieved, by wirelessly gathering the respective outputs of the sensing smart label through a Bluetooth protocol. This smart label (100) provides the capability of recording the thermal conditions at the surface of the fluid hose (10) and infer about its integrity. Simultaneously, the integrated energy harvesting system, composed by the thermoelectric harvester (101) and the heatsink (1011) , enables the complete autonomy of the smart label (100) , generating energy due to the thermal gradients applied on the fluid hose (10) .

[0057] In another proposed embodiment of the current invention, the smart label (100) can also integrate a printed flexible informative display (200) . The structure of the proposed flexible electroluminescent display (200) is based on a multi-layered structure composed of four distinct layers; produced by screen-printing technology, resourcing to the application of different functional inks. To provide the required flexibility and light transmission, a polymeric substrate as Polyethylene Terephthalate (PET) or Polyethylene naphthalate (PEN) can be considered. Each layer of the lighting device is deposited onto the end substrate by resorting to screen printing techniques. In this proposed embodiment, the a transparent conductive material (202) , which comprises one of a Poly ( 3 , 4-ethylenedioxythiophene ) polystyrene sulfonate (PEDOT:PSS) , is directly printed onto the polymeric substrate (201) . The subsequent layer (203) provides the electroluminescent feature, which can be of different colours, as blue or orange. A dielectric layer (204) is then printed to ensure the necessary insulation of the multi-layered structure. The final layer refers to the top electrode, being based on a conductive silver ink (205) . Regarding the printing process, the functional layers are printed through a screen-printing process over a 90x40 mesh (90 yarns / cm and 40 pm yarn diameter) , or a 140x31 mesh (140 yarns / cm and 31 pm yarn diameter) . After the printing of each ink with the defined pattern onto the end substrate, the respective films are cured in a thermal oven at temperatures ranging from 100°C to 110°C for approximately 10 to 20 minutes. At the end, the final printed display (200) is covered with an encapsulating layer over the top electrode, ensuring the necessary protection to external aggressions .

[0058] The electroluminescent display (200) is designed as a multisegment structure, providing the capability of displaying numbers and letters, both in lowercase and uppercase. Each character is comprised by fourteen segments, with individual width of 3 mm per segment and overall dimension of 50 mm x 38 mm. The end display (200) is constituted by at least three of the abovementioned characters. Therefore, in this display, information of several types can be presented, either as text (e. g. T°C) or numerical (e. g. 12.3) .

[0059] The operation of the electroluminescent display (200) requires a dedicated control electronics. The connections of the display segments to the electronics are ensured through the extension traces of the printed silver layer (top electrode) , creating a printed flat cable. At the end point of this flat cable, a connector ensures the connection to the remaining controlling electronics.

Claims

CLAIMS1. Device (100) for monitoring the surface temperature of rubber-based products characterized by comprising a temperature sensor (104) ; a control board (102) ; and a thermoelectric generator (101) .

2. Device (100) according to the previous claim, wherein the control board (102) is configured to acquire data from the temperature sensor (104) .

3. Device (100) according to any of the previous claims, wherein the data acquired from the temperature sensor (104) comprises temperature values of the surface of the rubberbased product where applied.

4. Device (100) according to any of the previous claims, wherein the temperature sensor (104) comprises an arrangement of layers comprising at least one of a metalbased layer on top of a polymeric substrate, protected by a polymeric top layer.

5. Device (100) according to any of the previous claims, wherein the control board (102) comprises at least one of an energy harvesting module, energy storage module, sensor acquisition module and communication module.

6. Device (100) according to any of the previous claims, wherein the thermoelectric generator (101) comprises an arrangement of layers comprising at least one thermocouple comprising a n-type thermoelectric pellet and a p-typethermoelectric pellet electrically connected in series, arranged between top and bottom ceramic layers.

7. Device (100) according to any of the previous claims, further comprising a display device (200) composed of an electronic control module and a set of at least three multisegment display.

8. Device (100) according to any of the previous claims, wherein the display device (200) is configured to provide visual information to a user, said visual information being provided by the control board (103) .

9. Device (100) according to any of the previous claims, characterized by being integrated on the surface of a fluid hose (10) through a compatible adhesive rubber-based material .

Images