System for temperature control in thermally insulated containers

Abstract

The present invention aims to automatically control the heating of and ensure minimal temperature variation inside thermally insulated containers during transportation, so that food maintains an ideal condition and temperature until it is delivered to the location agreed with the customer. The invention comprises a thermally insulated container (1), which is internally coated with a waterproof and thermally insulating adhesive material. Installed in said thermally insulated container (1) is a heating system comprising at least one electrical resistor (2) connected in series to at least two thermocouple / thermostat components (3) and (4) which operate redundantly with respect to one another, wherein the electrical resistor is positioned jointly with a plate (6) made from a thermally conductive material, which is positioned in the base of the container (1). The electrical power is supplied by a direct current battery (5) housed on the outside of the container (1).

Description

[0001] SYSTEM FOR CONTROLLING TEMPERATURE IN THERMAL CONTAINERS Field of the invention:

[0001] The present invention relates to a system for controlling the temperature in thermal containers designed primarily for transporting food products. In particular, the present invention discloses a system for controlling the temperature in thermal containers that ensures minimal variation in the internal temperature of the container, thus preserving the food product at an ideal temperature for consumption. Fundamentals:

[0002] The demand for food delivery services has been growing steadily. Therefore, when customers request food delivery, they expect the food to arrive quickly and in perfect condition, maintaining its integrity and ideal temperature for consumption.

[0003] Due to high consumer demands and concerns about the quality of the food being transported, food delivery companies are increasingly concerned about ensuring product quality and safety. When the order is not delivered on time and / or at the ideal temperature for consumption, the order ends up being returned by the customer, resulting in customer dissatisfaction with the company. Furthermore, food delivery professionals often feel pressured to deliver the products as quickly as possible, which is sometimes impossible due to unforeseen circumstances such as traffic jams. In certain situations, delivery professionals can put their own lives at risk, particularly by driving recklessly and at high speeds.

[0004] To overcome these problems, the present invention aims to offer the market a practical solution for maintaining food in ideal conditions of integrity and temperature during home delivery. This ensures that the product reaches the customer in perfect condition, avoiding potential returns and complaints, and contributing to the safety of delivery professionals. Prior art:

[0005] In the state of the art, documents can be found that reveal equipment for heating and also controlling the temperature inside thermal containers.

[0006] Documents BR 10 2019 013549 2, BR 13 2020 011930 2 and BR 132021 011770 1, for example, reveal heating systems applied to thermal containers in which heating is provided by means of electromagnetic induction, but without a system for controlling the temperature in the thermal container.

[0007] Document BR 20 2012 032105 5, in turn, reveals a thermal container that has a resistance that is powered by a car battery that remains attached to the vehicle, but also without a system to control the temperature in the thermal container.

[0008] Documents US 6,433,313, US 6,861,628 and US 8,168,923 reveal systems for temperature management, but only using thermostats and some diodes.

[0009] Although the prior art already discloses equipment for controlling the temperature inside thermal containers, none of these documents disclose a system as described, which has a specific configuration of elements, including a presence sensor, resulting in an improvement of the equipment as a whole and also resulting in a portable device that precisely ensures the smallest temperature variation inside the thermal container. Brief description of the invention:

[0010] More specifically, the present invention aims to automatically control heating and also ensure minimal temperature variation inside thermal containers during transportation, so that the food remains under ideal conditions and temperatures until it is delivered to the location agreed upon with the customer. The invention consists of a thermal container with a heating system that, by causing the internal temperature of the container to reach a designated value, ensures minimal variation of this internal temperature around this designated temperature value until the moment the food product is delivered to the location agreed upon with the customer.To maintain minimal temperature variation in the food, the heating system was designed to include at least one electrical resistance; at least two closed thermocouple / thermostat components with pre-set temperatures that operate redundantly, forming, together with the electrical resistance, the circuit responsible for heating the interior of the thermal container. The electrical resistance is positioned next to a plate made of a temperature-conducting material, which, in turn, is positioned at the base of the thermal container. The circuit responsible for heating the interior of the thermal container is powered by a circuit preferably containing a portable rechargeable DC battery and a presence sensor linked to a relay to allow or deny the flow of electric current and, consequently, activate or deactivate the circuit responsible for heating the interior of the thermal container.Brief description of the figures: .

[0011] In order to obtain a complete visualization of the object of this invention, figures of the object are presented in its preferred configuration: figure 1 illustrates the thermal container containing a protective plate positioned in its lower part.

[0012] Figure 2 illustrates the protective plate including a raised surface on its upper part and close to the container opening.

[0013] Figure 3 illustrates the presence sensor being positioned on one side of the thermal container, through a hole, through the exterior.

[0014] Figure 4 illustrates the presence sensor positioned internally in the thermal container through the hole.

[0015] Figure 5 illustrates the resistance used in the circuit responsible for heating the inside of the thermal container.

[0016] Figure 6 illustrates one of the thermostats used in the circuit responsible for heating the inside of the thermal container.

[0017] Figure 7 illustrates a view of the top of the heat conducting tray to which the resistance and thermostats are attached.

[0018] Figure 8 illustrates a view of the bottom of the heat conducting tray with the thermostats attached.

[0019] Figure 9 illustrates the assembly consisting of the resistance and temperature control components housed on the bottom face of the heat conducting tray.

[0020] Figure 10 illustrates the assembly consisting of the resistance and temperature control components housed on the underside of the heat conducting tray with the wires connected and the power supply polarity indicated.

[0021] Figure 11 illustrates the heat-conducting tray fixed to the base of the thermal container with its upper face facing upwards.

[0022] Figure 12 illustrates in detail the air inlets positioned on the front face of the heat conducting tray.

[0023] Figure 13 illustrates in detail the air outlets positioned on the rear face of the heat conducting tray.

[0024] Figure 14 illustrates a representation of the power supply circuit and the circuit responsible for heating the interior of the thermal container. Detailed description of the invention:

[0025] The present invention describes a system for temperature control in thermal containers that, by bringing the internal temperature of the container to a designated value, ensures minimal variation in this internal temperature until the moment the food product is delivered to the location agreed upon with the customer. To maintain minimal variation in the food temperature, said model comprises a thermal container (1) preferably lined on the inside with a waterproof and thermally insulating adhesive material, this adhesive material preferably being a film used for automotive wrapping. The purpose of coating the container internally is related to the fact that the internal surfaces of these containers are typically composed of porous materials such as Styrofoam, which are also non-heat insulating.In this way, the application of the coating ensures that the internal surface of the thermal container (1) remains completely impermeable to moisture and also provides insulation against heat, contributing to minimal variation in the internal temperature of the container for longer.

[0026] At the bottom inner part of the thermal container (1) a metal plate (1a) can be positioned first, which can be made of galvanized steel as illustrated in figure 1. This plate (1a) has the purpose of offering protection to the integrity of the bottom outer part of the thermal container (1), considering that the container is supported through its bottom outer part on the respective means of transport used for the delivery of the food product. The plate (1a) can also have a raised strip (1b) located at the top of the plate (1a) and close to the opening of the container as illustrated in figure 2. The raised strip (1b) has the function of providing additional resistance to deformation of the bottom part of the thermal container (1).

[0027] The power circuit consists of a portable rechargeable direct current battery (5), which can be 24 Volts, 36 Volts, or any other voltage necessary for the perfect operation of the model. In addition to the direct current battery (5), the power circuit comprises a presence sensor (8) and an "open and close" contact device, such as a relay. The presence sensor (8) is positioned internally in the thermal container (1) through a hole (1c) made in the thermal container (1), as illustrated in figures 3 and 4. The presence sensor (8) has the function of detecting the presence of the food product inside the thermal container (1). When the presence of the food product is detected by the presence sensor (8), the power circuit is activated through the contact device, allowing the passage of electric current through the power circuit.On the other hand, when the presence sensor (8) no longer detects the presence of the food product inside the thermal container (1), the power circuit is deactivated by the contact device, ceasing the passage of electric current through it. The representation of the power circuit can be seen in figure 14 which also shows the representation of the circuit responsible for heating the inside of the thermal container (1) which is connected to the power circuit. .

[0028] The circuit responsible for heating the interior of the thermal container (1) is composed of a resistance (2) preferably shielded and with stainless steel piping, as illustrated in figure 5, with the resistance (2) being connected in series to a first temperature control component (3) and a second temperature control component (4). The temperature control components (3, 4) may be, for example, thermostats, as illustrated in figure 6.

[0029] Temperature control components (3) and (4) are set to pre-set temperatures and operate redundantly. Redundancy is adopted in the operation of temperature control components (3) and (4) for safety (back-up), in order to ensure that the circuit does not overheat and that the heat generated by the resistance (2), when the circuit responsible for heating is activated, does not cause an excessive temperature inside the thermal container (1). Thus, the temperature control component (3) is designed to operate with a first pre-set cut-off temperature value (Tc) and a pre-set trigger temperature value (Ta).The temperature control component (4) is designed to operate with a second cutting temperature value (Tc') also pre-established, and the second cutting temperature value (Tc') is always greater than the first cutting temperature value (Tc), i.e., Tc' > Tc. .

[0030] Thus, as the presence sensor (8) detects the presence of the food product inside the thermal container (1), the power circuit is activated through the contact device, thus activating the circuit responsible for heating the inside of the thermal container (1). As the temperature control components (3) and (4) are connected to each other in series, and these are also connected in series to the resistance (2), when the temperature value inside the thermal container (1) reaches the first pre-established cut-off temperature value (Tc), the component (3) causes the circuit to open, interrupting the passage of electric current through it and causing the resistance (2) to no longer generate heat.On the other hand, after the circuit is opened and the actuation temperature (Ta) is reached by the temperature control component (3), it causes the circuit to close, allowing the passage of electric current and causing the resistance (2) to generate heat again. This process of opening and closing the circuit is carried out automatically by the temperature control component (3) in a minimum time interval so that the internal temperature of the thermal container varies as little as possible.

[0031] The temperature control component (4) remains operating in closed (short) mode and only changes its operating mode if the temperature control component (3) presents a failure and remains in closed (short) mode even after reaching the first cut-off temperature value (Tc). Therefore, the presence of the temperature control component (4) is only for the safety of the equipment, in order to ensure that the passage of electric current through the circuit is interrupted if the temperature inside the container (1) reaches the second cut-off temperature value (Tc').

[0032] The entire assembly consisting of the resistance (2) and the temperature control components (3) and (4) is housed in the lower face of a heat conducting tray (6), preferably made of metallic material such as aluminum, as illustrated in figures 7, 8 and 9. The heat conducting tray (6) is positioned at the base of the thermal container (1). As the assembly consisting of the resistance (2) and the temperature control components (3) and (4) is housed in the lower face of the heat conducting tray (6), it remains with its upper face facing upwards, inside the thermal container (1), which means that users do not have direct access to the resistance (2), as illustrated in figure 11.Furthermore, when housing the heat-conducting tray (6) in the thermal container (1), its proper thermal insulation is provided through its base using insulators such as silicone and Teflon, so that the heat is not directly transferred from the tray (6) to the surface of the thermal container (1). Furthermore, a certain distance is maintained between the side and rear faces of the heat-conducting tray (6) and the container (1).

[0033] The heat conducting tray (6) comprises at least one air inlet (6b) on its front face and at least one air outlet (6c) on its rear face so as to generate an air convection current within the container (1), which contributes to helping with the minimum temperature variation. Figures 12 and 13 illustrate the heat conducting tray (6) with two air inlets (6b) on its front face and three air outlets (6c) on its rear face.

[0034] The direct current battery (5) is fixed to the upper part of the thermal container (1) and at a minimum distance from the heating system. Therefore, considering that the electric resistance (2) is installed in the lower internal part of the container (1) together with the heat conducting tray (6), the battery is preferably installed in the upper external part of the container (1), preferably at least 35 cm away from the electric resistance (2) and the heat conducting tray (6), ensuring that there is no heat transfer from the inside of the container (1) to the battery (5).

[0035] It's important to note that the DC battery (5) can be equipped with a BMS (battery management system) safety board. The BMS is an electronic safety system that is part of the battery (supplied by the manufacturer) and is responsible for monitoring and controlling lithium batteries. The BMS monitors the voltage, current, temperature, and state of charge of the batteries, providing greater safety.

Claims

CLAIMS 1. SYSTEM FOR CONTROLLING TEMPERATURE IN THERMAL CONTAINERS, characterized by the fact that it comprises: - power supply circuit composed of a battery (5), presence sensor (8) and “open and close” contact device; - circuit responsible for heating the interior of the thermal container (1) composed of a resistance (2) connected in series to a first temperature control component (3) and to a second temperature control component (4), the resistance (2) and the components (3, 4) being housed in the lower face of a heat-conducting tray (6) that is positioned at the base of the thermal container (1), the heat-conducting tray (6) comprising at least one air inlet (6b) on its front face and at least one air outlet (6c) on its rear face.

2. SYSTEM FOR CONTROLLING TEMPERATURE IN THERMAL CONTAINERS, according to claim 1, characterized by the fact that the battery (5) is fixed to the external part of the container (1).

3. SYSTEM FOR CONTROLLING TEMPERATURE IN THERMAL CONTAINERS, according to claim 1, characterized by the fact that the presence sensor (8) is positioned in the internal part of the thermal container (1) through an orifice (1c).

4. SYSTEM FOR CONTROLLING TEMPERATURE IN THERMAL CONTAINERS, according to claim 1, characterized by the fact that the container (1) is coated on the inside by a waterproof and thermally insulating adhesive material.

5. SYSTEM FOR CONTROLLING TEMPERATURE IN CONTAINERS. THERMAL, according to claim 1, characterized by the fact that a metal plate (1a) is positioned in the lower external part of the thermal container (1).

6. SYSTEM FOR CONTROLLING TEMPERATURE IN THERMAL CONTAINERS, according to claim 5, characterized by the fact that the plate (1a) has a raised strip (1b) located in its upper part and close to the opening of the container (1).

7. SYSTEM FOR CONTROLLING TEMPERATURE IN THERMAL CONTAINERS, according to claim 1, characterized by the fact that the resistance (2) is shielded and with stainless steel piping. 8.SYSTEM FOR CONTROLLING TEMPERATURE IN THERMAL CONTAINERS, according to claim 1, characterized by the fact that the temperature control component (3) is designed to operate with a first cut-off temperature value (Tc) and a trigger temperature value (Ta) and the temperature control component (4) is designed to operate with a second cut-off temperature value (Tc'), where Tc' > Tc.

9. SYSTEM FOR CONTROLLING TEMPERATURE IN THERMAL CONTAINERS, according to claim 1, characterized by the fact that the heat-conducting tray (6) is housed in the thermal container (1) with application of thermal insulation through its base by means of insulators such as silicone and Teflon.

10. SYSTEM FOR CONTROLLING TEMPERATURE IN THERMAL CONTAINERS, according to claim 9, characterized by the fact that when housing the heat-conducting tray (6) in the thermal container (1), a certain distance is maintained between them. side and rear faces of the heat conducting tray (6) and the container (1).

11. SYSTEM FOR CONTROLLING TEMPERATURE IN THERMAL CONTAINERS, according to claim 1, characterized in that the battery (5) is fixed to the container (1) at least 35 cm from the electrical resistance (2) and the heat conducting tray (6).

12. SYSTEM FOR CONTROLLING TEMPERATURE IN THERMAL CONTAINERS, according to claim 11, characterized in that the battery (5) is equipped with a BMS (battery management system) safety board.

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