GB2629604A

GB2629604A - Systems and methods for sealing food containers

Info

Publication number: GB2629604A
Application number: GB2306542.8A
Authority: GB
Inventors: Vine Lee; Smart Oliver
Original assignee: Ishida Europe Ltd
Current assignee: Ishida Europe Ltd
Priority date: 2023-05-03
Filing date: 2023-05-03
Publication date: 2024-11-06
Also published as: GB202306542D0; WO2024228029A1

Abstract

A sealing system for food containers is disclosed. The sealing system comprises a frame and a conveyor system for conveying food containers through the sealing system, wherein the conveyor system is supported by the frame. A sealing unit is configured to receive food containers from the conveyor system, wherein the sealing unit comprises a first sealing tool and a second sealing tool configured to be pressed together in order to seal each food container positioned therebetween, wherein the sealing unit is supported by the frame, and wherein the conveyor system is further configured to convey sealed food containers away from the sealing unit. A power monitoring unit is configured to measure a power consumption of the sealing system. A control unit is configured to calculate an energy consumption per sealed food container based on the power consumption and the number of sealing operations performed per unit time, and output an indication derived from the calculated energy consumption per sealed food container.

Description

SYSTEMS AND METHODS FOR SEALING FOOD CONTAINERS FIELD OF THE INVENTION

The present invention relates to a food container sealing system and a method for sealing food containers. The invention is particularly applicable to food containers such as trays of food which may be sealed with a film lid. The invention is concerned with measuring the power consumption of such systems and outputting indications derived from the power consumption in order to assist operators in improving the energy efficiency and/or sealing performance of the system.

BACKGROUND

Many systems and methods of sealing food containers use a high pressure generated between two sealing tools to seal a container. A particular example of such a system is a tray sealing system, which generally seals a film lid to a tray using heat and pressure to seal the film along a sealed seam about the periphery of the tray. Another example of such a system is a skin seal system, which forms a sealed container by evacuating the air between a tray or sheet and a film cover, before sealing the film over the food product, again along a sealed seem generated using heat and pressure.

In these processes that form seals using heat and pressure, various factors affect the quality of the seal formed, including the time that the heat and pressure are exerted over, the temperature used in the sealing process, and the pressure being used to form the seals. Operators may regularly adjust these settings in an attempt to achieve desired sealing properties. Further settings such as the wait time of the sealing unit and the speed at which containers are conveyed through the system may also be adjusted depending on operational requirements.

Due to the manual adjustability of these operational parameters, it is common to observe sealing systems being operated using settings which are inappropriate with respect to the sealed product. For example, an operator may have adjusted the sealing temperature far beyond the sealing temperature required for the film material, or the conveyor may have been configured to run at a much greater speed than is necessary for the number of containers being transported. In other words, sealing systems are often set-up to operate with a low energy efficiency without providing any further benefit to the sealed product.

It is therefore desirable to provide a system and method of sealing food containers which is able to assist operators in optimising the energy efficiency of the sealing operation, thereby reducing the operational cost of the system.

SUMMARY OF INVENTION

According to a first aspect of the invention, there is provided a sealing system for food containers, comprising: a frame; a conveyor system for conveying food containers through the sealing system, wherein the conveyor system is supported by the frame; a sealing unit configured to receive food containers from the conveyor system, wherein the sealing unit comprises a first sealing tool and a second sealing tool configured to be pressed together in order to seal each food container positioned therebetween, wherein the sealing unit is supported by the frame, and wherein the conveyor system is further configured to convey sealed food containers away from the sealing unit; a power monitoring unit configured to measure a power consumption of the sealing system; and a control unit configured to: calculate an energy consumption per sealed food container based on the power consumption and the number of sealing operations performed per unit time; and output an indication derived from the calculated energy consumption per sealed food container.

In this way, by utilising a power consumption monitor to measure the power consumption and subsequently outputting an indication derived from the calculated energy consumption per sealed food container, the invention enables an operator to improve the energy efficiency of the sealing system by providing feedback regarding the energy usage during operation of the system. In contrast, in conventional sealing systems which are not configured to monitor power consumption or output information derived from the measured power consumption, inappropriate operational parameters may be used resulting in a high energy usage unbeknownst to the operator.

It will be appreciated that when the first and second tools are pressed together, they may not physically contact one another because of the food container located therebetween. Typically, one of the first and second sealing tools is coupled to an actuator for moving said sealing tool in order to bring the first and second sealing tools together so as to be pressed together. Preferably, the actuator is configured to move the sealing tool in a linear and reciprocal manner from an open position, at which a food container to be sealed may be received, to a closed position, at which the sealing tool is pressed against the opposing sealing tool in order to seal the container.

Preferably, the control unit is further configured to: calculate a measure of energy efficiency of the sealing system based on a comparison of the energy consumption per sealed food container to a threshold energy consumption; and output an indication derived from the measure of energy efficiency, wherein the indication derived from the energy consumption per sealed food container comprises the indication derived from the measure of energy efficiency. In this way, by utilising a threshold energy consumption, the sealing system may further assist the operator in optimising the energy efficiency as the calculated measure of energy efficiency will take into account an optimum energy usage for the system. The indication derived from the measure of energy efficiency is therefore able to guide the operator to achieve optimum functioning of the system.

Preferably, the sealing system further comprises a data storage device disposed within the sealing unit, wherein the threshold energy consumption is a predetermined threshold energy consumption, and wherein data indicative of the threshold energy consumption is stored within the data storage device. In this way, the threshold energy consumption may be linked to an individual sealing unit.

Preferably, the control unit is configured to receive data indicative of properties associated with the food containers to be sealed, and wherein the control unit is configured to determine the threshold energy consumption based on the properties associated with the food containers to be sealed. In this way, the threshold energy consumption may be accurately determined and updated depending on the dimensions, materials etc. of the food containers.

Preferably, the properties associated with the food containers to be sealed comprise one or more of: a sealing area of each food container; a sealing material for each food container; and a material of each food container.

Preferably, the control unit is configured to receive data indicative of the threshold energy consumption from an external computing device. In this way, the threshold energy consumption may be adjusted and updated as required.

Preferably, the external computing device is configured to receive energy consumption data from a plurality of other sealing systems for food containers, and wherein the threshold energy consumption is calculated based on the energy consumption data. In this way, the threshold energy consumption may be adjusted and updated based on data analytics regarding the energy usage of other sealing systems, e.g. based on big data.

Preferably, the control unit is further configured to: receive one or more operational parameters of the sealing system; and output a prompt to adjust the one or more operational parameters of the sealing system in response to determining that the energy consumption per sealed food container is greater than the threshold energy consumption per sealed food container or in response to determining that consumption per sealed food container is less than the threshold energy consumption per sealed food container, and wherein the prompt is based on the energy consumption per sealed food container and the one or more operational parameters. In this way, the control unit further assists operators in improving the energy efficiency and/or sealing performance of the system by providing a prompt to adjust the operational parameters in view of the received operational parameters and difference between the threshold energy usage and the actual energy usage. Operational parameters of the sealing process may therefore be controlled in a continued and guided manner, based on real time feedback.

Preferably, the control unit is configured to output the prompt to adjust the one or more operational parameters of the sealing system in response to determining that the energy consumption per sealed food container is greater than the threshold energy consumption per sealed food container by a first percentage of the threshold energy consumption per sealed food container. In this way, the control unit assists operators in optimising the energy efficiency of the system. Alternatively, the control unit may be configured to output the prompt to adjust the one or more operational parameters of the sealing system in response to determining that the energy consumption per sealed food container is greater than the threshold energy consumption per sealed food container by a first predetermined value.

Preferably, the control unit is configured to output the prompt to adjust the one or more operational parameters of the sealing system in response to determining that the energy consumption per sealed food container is less than the threshold energy consumption per sealed food container by a second percentage of the threshold energy consumption per sealed food container. In this way, the control unit assists operators in improving the sealing performance of the system, as a particularly high energy efficiency may be indicative of containers not being properly sealed. Alternatively, the control unit may be configured to output the prompt to adjust the one or more operational parameters of the sealing system in response to determining that consumption per sealed food container is less than the threshold energy consumption per sealed food container by a second predetermined value.

Preferably, the sealing system further comprises a strain gauge configured to measure a sealing force when the first sealing tool and the second sealing tool are pressed together, wherein the one or more operational parameters comprise the sealing force, and wherein the prompt comprises an indication to adjust the sealing force.

Preferably, the sealing system further comprises a temperature sensor configured to measure a sealing temperature when the first sealing tool and the second sealing tool are pressed together, wherein the one or more operational parameters comprise the sealing temperature, and wherein the prompt comprises an indication to adjust the sealing temperature.

Preferably, the one or more operational parameters comprise at least one of a speed of the conveyor system, a dwell time of the sealing unit, and a wait time of the sealing unit, and wherein the prompt comprises an indication to adjust at least one of the speed of the conveyor system, the dwell time of the sealing unit, and the wait time of the sealing unit.

Preferably, the sealing system further comprises a display unit supported by the frame, wherein the control unit is configured to output the indication derived from the calculated energy consumption per sealed food container at the display unit.

Preferably, the sealing unit is a heat-sealing tool configured to heat seal a film lid to the container along a sealed seam.

According to a second aspect of the invention, there is provided a sealing system for food containers, comprising: a frame; a conveyor system for conveying food containers through the sealing system, wherein the conveyor system is supported by the frame; a sealing unit configured to receive food containers from the conveyor system, wherein the sealing unit comprises a first sealing tool and a second sealing tool configured to be pressed together in order to seal each food container positioned therebetween, wherein the sealing unit is supported by the frame, and wherein the conveyor system is configured to convey sealed food containers away from the sealing unit; a power monitoring unit configured to measure a power consumption of the sealing system; and a control unit configured to: calculate a measure of power efficiency of the sealing system based on a comparison of the power consumption to a threshold measure of power consumption; and output an indication derived from the measure of power efficiency of the sealing system.

Preferably, the control unit is further configured to calculate an energy consumption per sealed container based on the power consumption and the number of sealing operations performed per unit time; and output an indication of the electrical energy consumption per sealed container.

Preferably, the sealing system further comprises a data storage device disposed within the sealing unit, wherein the threshold power consumption is a predetermined threshold power consumption, and wherein data indicative of the threshold power consumption is stored within the data storage device.

Preferably, the control unit is configured to receive data indicative of properties associated with the container to be sealed, and wherein the control unit is configured to determine the threshold power consumption based on the properties associated with the container.

Preferably, the control unit is configured to receive data indicative of the threshold power consumption from an external computing device. Preferably, the external computing device is configured to receive energy consumption data from a plurality of other sealing systems for food containers, wherein the threshold power consumption is calculated based on the energy consumption data.

Preferably, the control unit is further configured to: receive one or more operational parameters of the sealing system; and output a prompt to adjust the one or more operational parameters of the container sealing system in response to determining that the power consumption is greater than the threshold power consumption or in response to determining that the power consumption is less than the threshold power consumption, and wherein the prompt is based on the power consumption and the one or more operational parameters.

Preferably, the control unit is configured to output the prompt to adjust the one or more operational parameters of the sealing system in response to determining that the power consumption is greater than the threshold power consumption by a first percentage of the threshold power consumption. Alternatively, the control unit may be configured to output the prompt to adjust the one or more operational parameters of the sealing system in response to determining that the power consumption is greater than the threshold power consumption by a first predetermined value.

Preferably, the control unit is configured to output the prompt to adjust the one or more operational parameters of the sealing system in response to determining that the power consumption is less than the threshold power consumption by a second percentage of the threshold power consumption. Alternatively, the control unit may be configured to output the prompt to adjust the one or more operational parameters of the sealing system in response to determining that the power consumption is less than the threshold power consumption by a second predetermined value.

Preferably, the sealing system further comprises a display unit, wherein the control unit is configured to output the indication derived from the measure of power efficiency of the sealing system at the display unit.

According to a third aspect of the invention, there is provided a method of operating a food container sealing system, comprising: conveying, using a conveyor system, food containers to a sealing unit comprising a first sealing tool and a second sealing tool; pressing the first sealing tool and the second sealing tool together so as to seal each food container positioned therebetween; measuring, using a power monitoring unit, a power consumption of the sealing system; calculating, using a control unit, an energy consumption per sealed food container based on the power consumption and the number of sealing operations performed per unit time; and outputting, using the control unit, an indication derived from the energy consumption per sealed food container.

Preferably, the method of the third aspect may be performed using a system of the first or second aspect.

BRIEF DESCRIPTION OF DRAWINGS

The invention will now be described with reference to the accompanying drawings, of which: Figure 1 is a perspective view of a system for sealing food trays; and Figure 2 is a front view of the system for sealing food trays, wherein the system is in an open tool position.

DETAILED DESCRIPTION

An exemplary system will now be described with reference to Figure 1. The system shown in Figure 1 is a tray sealing system 1, which may also be referred to as a sealing system for food containers. The system 1 comprises a frame 100 that supports various elements of the system 1. The frame 100 may comprise a number of housing panels that close the frame 100 and form a housing for the elements of the system. The system 1 comprises a film supply unit 10 that has a film supply reel 11 that supplies film as a web through the system along a film transport path 13 and to an uptake reel 12 that receives excess film. The system 1 also comprises a sealing unit 20 for lifting trays of food product, sealing the film to the tray and cutting the film from the film web. The trays of food product may also be referred to as food containers. As will be described below, the sealing unit 20 comprises an upper tool 21 (e.g. a first sealing tool) and a lower tool 22 (e.g. a second sealing tool) that are pressed together as part of this sealing process by an actuator 25 coupled to the lower sealing tool 22. The system also comprises a display unit 30 (e.g. an HMI display) provided with a user interface for controlling the operation of the system and a conveyor system 40 for conveying trays through the system. The display unit 30 is configured to display information regarding the operation of the system 1, as will be discussed further below. Additionally or alternatively, the operation of the system 1 may be controlled using an external computing device, e.g. via a network connection to the system 1. The conveyor system 40 is positioned within the frame 100 and comprises a first conveyor belt 41 that receives a tray to be sealed at an input end of the system 1 and conveys the tray to the sealing unit 20. From there, the tray may be transferred to into the sealing unit 20, for example by gripping arms, for sealing and then transferred out of the sealing unit 20 after sealing. A second conveyor belt 42 receives the sealed tray and conveys them to an output end of the system 1.

As best illustrated in Figure 2, the sealing unit 20 is located in a substantially central portion of the system 1. The sealing unit 20 comprises the upper sealing tool 21, which is substantially fixedly mounted to the frame 100, although will typically comprise movable parts within the upper sealing tool 21. The sealing unit is configured to perform tray or skin sealing, such that the upper sealing tool 21 will typically comprise a heat-sealing plate for heat sealing the film delivered along the film transport path 13 to the rim of a tray or other support, and a cutting tool for cutting out an area of the film that is sealed to the tray or support. The lower sealing tool 22 will typically comprise a receiving portion, configured to receive a tray or support to be sealed. The actuator 25 may lift the lower sealing tool 22 and press the lower sealing tool 22 against the upper sealing tool 21 to cause sealing to occur. Once the upper and lower sealing tools 21, 22 are closed, the actuator 25 may further lift the lower sealing tool 22, which may cause relative movement of components within one or both of the upper and lower sealing tools 21, 22. For example, the upper tool 21 may comprise a heat-sealing plate and a cutting tool mounted on springs to a body or housing of the upper sealing tool 21, such that upward movement of the body or housing of the upper sealing tool 21 as it is pressed by the lower tool 22 causes the heat-sealing plate and the cutting tool to project from the body or housing of the upper sealing tool 21 and contact the tray. Such an arrangement of a heat-sealing plate and cutting tool within an upper sealing tool is described in co-pending application PCT/GB2021/052230.

A temperature sensor 70 is provided within the frame 110 and is arranged to measure the sealing temperature, e.g. the temperature of the heat-sealing plate during each sealing operation. For example, the temperature sensor 70 may be located on or adjacent to the heat-sealing plate.

A strain gauge 121 is coupled to frame 100 and is configured to measure the sealing force when the upper sealing tool 121 is pressed against the lower sealing tool 122 during a sealing operation. In particular, the strain gauge 121 may be configured to measure the force transmitted through the frame 100 during sealing, which can be resolved into a sealing force. For example, the strain gauge 121 may be provided on a portion of the frame 100 that is parallel with the direction along which the sealing tools 121, 122 are pressed together, and is in pure tension, which enables the sealing force to be easily resolved. The strain gauge 121 may be, for example, be a two-hole bolt-on strain gauge sensor.

The skilled person will understand that the strain gauge 121 may need calibrating before it can be used during normal use. This calibration may comprise placing a load cell in the sealing tool 120 and using the actuator 25 to press the upper and lower sealing tools 121, 122 together with the load cell therebetween to generate a range of forces as detected by the load cell. The output from the strain gauge 121 is recorded as the upper and lower sealing tools 121, 122 are pressed together and the strain gauge 121 output plotted against the measured forces from the load cell, from which can be derived a relationship between the strain gauge measurements and the sealing force, typically in mV*kN-1. The load cell may then be removed before normal use of the system 1.

The system 1 further comprises a power monitoring unit 60 configured to measure the power consumption of the system 1, i.e. measure the amount of energy consumed per unit time during operation of the system 1. The power monitoring unit 60 is supported by the frame 100 and arranged to monitor the incoming electrical feed to the system 1. For example, the power monitoring unit 60 may be mounted at or adjacent to a power inlet of the system 1 such that the incoming power to the system 1 can be measured by power monitoring unit 60. The system 1 also comprises a control unit 50 (e.g. a microprocessor) which is communicatively coupled to the power monitoring unit 60. The control unit 50 receives data indicative of the measured power consumption from the power monitoring unit 60. As illustrated in Figure 1, the control unit 50 is supported by the frame 100 and is a standalone component with respect to the display unit 30. However, in alternative examples, the control unit 50 may be integrated as or within the display unit 30. In further examples, the control unit 50 may be located externally to the frame 100, e.g. in a different geographical location, and be configured to communicate with components of the system 1 via a network connection. In some embodiments, the control unit 50 may be referred to as a computing system or may be comprised within a computing system.

In general, the purpose of the control unit 50 is to receive operational data from 30 one or more components of the sealing system 1 and provide feedback to an operator which helps the operator to optimise the energy usage of the system 1.

In conventional sealing systems, it is typical for operators to perform sealing operations using inappropriate or excessive operational parameters which draw large amounts of power without improving the quality, consistency or speed of the sealing operation. Hence, by providing the control unit 50 which is able to output an indication to the user regarding the energy usage of the system 1 based on the measured power consumption of the system 1, the operator is guided to improve the energy efficiency of the system 1, thereby reducing the overall operational cost.

In particular, the control unit 50 is configured to calculate an energy consumption per sealed tray based on the power consumption measured by the power monitoring unit 60 and the number of sealing operations performed per unit time. For example, if the power consumption of the system is measured to be 120W, and the number of sealing operations per second is 0.1, the energy consumption per sealed tray will be calculated as 1200J. The number of sealing operations performed per unit time may be a pre-set parameter of the sealing operation which is retrievable by the control unit 50, e.g. programmed via user input at the display unit 30 or programmed at an external computing device and sent to the control unit 50 via a network connection.

The control unit 50 is further configured to output an indication derived from the calculated energy consumption per sealed tray. In the simplest example, this may be an indication of the actual value of the calculated energy consumption per sealed tray, e.g. "1200J per sealed tray". Alternatively, the value of the calculated energy consumption per production batch or the value of the calculated energy consumption per production shift may be calculated and output by the control unit 50. The indication derived from the calculated energy consumption per sealed tray may also comprise or consist of an indication of or derived from a calculated measure of energy efficiency of the system, as will be discussed further below.

The control unit 50 may output the indication derived from the calculated energy consumption per sealed tray via the display unit 30, such that the indication derived from the energy consumption per sealed tray is displayed on the display unit 30. Alternatively or additionally, the control unit 50 may output the indication derived from the calculated energy consumption per sealed tray via an external computing device, e.g. data indicative of the calculated energy consumption per sealed tray may be sent via a network to an external computing device, where it may be displayed. Based on this indication, the operator is guided to adjust the operational parameters of the system 1 in order to reduce its energy usage.

The control unit 50 is configured to calculate a measure of energy efficiency of the sealing system 1 based on a comparison of the energy consumption per sealed tray to a threshold energy consumption. The threshold energy consumption may be considered as an optimum or target energy consumption per sealed tray. The control unit 50 may receive the threshold energy consumption in a number of different ways. In a first example, the sealing unit 20 may comprise a data storage device (not illustrated) on which data indicative of the threshold energy consumption may be stored. The data indicative of the threshold energy consumption may be stored prior to installation of the sealing unit 20 in the system 1, e.g. pre-programmed by the manufacturer. In a second example, the control unit 50 may additionally or alternatively be configured to calculate the threshold energy consumption based on properties (e.g. dimensions and materials) of the tray and/or film, which may be received via user input at the display unit 30. For example, the control unit 50 may be configured to receive data indicative of the sealing area of each tray, a material of the film to be used for sealing, and/or a material of each tray, and calculate a threshold energy consumption based on one or more of these properties. In a third example, the control unit 50 may additionally or alternatively be configured to receive the threshold energy consumption from an external computing device. In particular, the control unit 50 may receive data indicative of the threshold energy consumption via a network connection to the external computing device. The external computing device may calculate the threshold energy consumption based on energy consumption data received from a plurality of other sealing systems for food trays.

The calculated measure of energy efficiency of the sealing system provides a relative measure of the energy consumption of the system 1 with respect to the threshold energy consumption. Typically, the measure of energy efficiency may be a ratio or percentage of the energy consumption per sealed food tray with respect to the threshold energy consumption per sealed tray. For example, if the energy consumption per sealed tray is 1800J and the threshold energy consumption per sealed tray is 1200J, the measure of energy efficiency may be calculated to be 1800/1200 = 1.5, i.e. the energy usage of the system 1 is 150% of the target energy usage. This would indicate that 50% additional energy is being wasted to achieve each sealed tray. If the energy consumption per sealed tray is 900J and the threshold energy consumption per sealed tray is 1200J, the measure of energy efficiency may be calculated to be 900/1200 = 0.75, i.e. the energy usage of the system 1 is 75% of the target energy usage. This would indicate that the system may not be operating correctly, e.g. trays are not being properly sealed.

In alternative embodiments, the measure of energy efficiency may be a ratio or percentage of the threshold energy consumption per sealed food tray with respect to the energy consumption per sealed tray, e.g. threshold energy consumption per sealed food tray / energy consumption per sealed tray.

The control unit 50 is further configured to output an indication derived from the calculated measure of energy efficiency, which may correspond to the earlier-mentioned indication derived from the calculated energy consumption per sealed tray. The indication derived from the calculated energy efficiency may be an indication of the actual value of the calculated measure of energy efficiency, e.g. "150%". Alternatively or additionally, the indication may be a graphical, pictorial or other representation which provides an operator an indication of the energy efficiency of the system 1, such as a RAG status. For example, if the calculated energy efficiency is below a first upper threshold value (e.g. the energy consumption of the system 1 is below 105% of the target energy consumption), the control unit 50 may output an indication of a "good" energy efficiency, such as a green status indication displayed on the display unit 30. If the calculated energy efficiency is between or equal to the first lower threshold value and a second upper threshold value (e.g. the energy consumption of the system 1 is above or equal to 105% of the target energy consumption and less than 120% of the target energy consumption), the control unit 50 may output an indication of a "poor" energy efficiency, such as an amber status indication display on the display unit 30. If the calculated energy efficiency is above the second threshold value (e.g. the energy consumption of the system 1 is above 120% of the target energy consumption), the control unit 50 may output an indication of a "poor" energy efficiency, such as a red status indication displayed on the display unit 30. In this way, an operator may be further assisted in optimising the energy efficiency of the system 1 based on the indication derived from the calculated measure of energy efficiency.

The control unit 50 is further configured to receive one or more operational parameters of the system 1 and output a prompt or recommendation to improve the energy efficiency of the system 1 based on these operational parameters and the calculated energy consumption per tray. The one or more operational parameters may comprise a sealing force, a sealing temperature, a wait time of the sealing unit 20 (i.e. the time between each sealing operation), a dwell time of the sealing unit 20 (i.e. the duration of contact between the sealing unit, film and tray), a speed of the conveyor system 40 and/or any other operational parameter of the system 1. A first subset of the one or more operational parameters may be measured by respective sensors of the system 1, such as the temperature sensor 70 which measures the sealing temperature and the strain gauge 121 which measures the sealing force. Such sensors are communicatively coupled to the control unit 50 and configured to send (data indicative of) the measured operational parameters to the control unit 50. A second subset of the one or more operational parameters may be pre-set parameters of the sealing operation which are retrievable by the control unit 5, e.g. programmed via user input at the display unit 30 or programmed at an external computing device and sent to the control unit 50 via a network connection. These pre-set parameters include the wait time of the sealing unit 20, the dwell time of the sealing unit 20, and the speed of the conveyor system 40.

The prompt is intended to assist the operator in improving the energy efficiency and/or sealing performance of the system 1. More specifically, the prompt may comprise an indication to adjust one or more operational parameters of the system 1, e.g. "reduce sealing force" or "sealing temperature too high". The control unit 50 may be configured to output the prompt via the display unit 30, such that the prompt is displayed on the display unit 30. Alternatively or additionally, the control unit 50 may be configured to output the prompt via an external computing device, e.g. data indicative of the prompt may be sent via a network to an external computing device, where the prompt may be displayed.

The prompt may only be output under certain operational conditions. In particular, the control unit 50 may be configured to output the prompt in response to determining that the energy consumption per sealed container is greater than the threshold energy consumption per sealed tray (e.g. greater than the threshold energy consumption per sealed tray by a first percentage of the threshold energy consumption per sealed tray) or in response to determining that the energy consumption per sealed tray is less than the threshold energy consumption per sealed tray (e.g. less than the threshold energy consumption per sealed tray by a second percentage of the threshold energy consumption per sealed tray). In the former case, the prompt is aimed at adjusting operational parameters which result in a poor energy efficiency without a particular improvement in sealing performance, i.e. the operational parameters are set excessively high or low leading to a high energy usage. For example, there is a tendency for operators to run conveyor belts at a high speed even though the sealing unit has been programmed to operate with a low wait time. In this case, the high speed of the conveyor system 40 may result in a poor energy efficiency, and the control unit 50 would therefore output a prompt including an indication to reduce the (unnecessarily high) speed of the conveyor system 40. There is also a tendency for operators to increase the sealing force beyond what is necessary for the film to be sealed to the tray. This is also likely to result in a poor energy efficiency, so the control unit 50 may therefore output a prompt including an indication to reduce the sealing force. In contrast, in the latter case above, the prompt is aimed at adjusting operational parameters to improve the sealing performance of the system 1, as a particularly high energy efficiency may be an indication that an insufficient amount of energy is going into the seal such that the trays are not being properly sealed. The control unit 50 may therefore output a prompt, based on the operational parameters and calculated energy consumption per tray, including a recommendation to improve the sealing performance. For example the prompt may comprise an indication to increase the sealing force and/or sealing temperature.

In some embodiments, the control unit 50 determining that the energy consumption per tray is greater than the threshold energy consumption per tray by the first percentage of the threshold energy consumption per sealed container may be equivalent to the control unit 50 determining that the calculated energy efficiency is above the first upper threshold energy efficiency. Similarly, the control unit 50 determining that the energy consumption per tray is less than the threshold energy consumption per tray by the second percentage of the threshold energy consumption per tray may be equivalent to determining that the calculated measure of energy efficiency is below a lower threshold energy efficiency.

In general, the control unit 50 is configured to receive one or more of the operational parameters noted above, and output the prompt including an indication to adjust one or more these operational parameters, based on the calculated energy consumption per sealed tray and the one or more operational parameters. Although the prompt may be generated based on a plurality of operational parameters (e.g. the sealing temperature and the sealing force), the prompt will not necessarily include an indication to adjust all of these operational parameters (e.g. the prompt may only include an indication to adjust the sealing temperature, and not the sealing force).

In a first example, the operational parameters received by the control unit 50 include the sealing temperature, the sealing force, the wait time of the sealing unit 20, and the dwell time of the sealing unit 20. The control unit 50 determines that the wait time of the sealing unit 20 is above a threshold wait time (i.e. indicative of an inefficient throughout of containers in which the sealing unit 20 is often inactive). To improve the energy efficiency of the system 1, the prompt generated by the control unit 50 therefore includes an indication to reduce the sealing temperature, the sealing force, and the wait time of the sealing unit 20, and to increase the dwell time of the sealing unit 20. By increasing the time over which the sealing unit 20 is in contact with each container, this allows for a reduction in the sealing temperature and sealing force without negatively affecting the sealing quality. In the way, the energy efficiency of the system 1 can be improved.

In a second example, the control unit 50 determines that a first operational parameter of the received operational parameters is above or below a first threshold value and that a second operational parameter of the received operational parameters is above or below a second threshold value. The prompt generated by the control unit 50 therefore includes an indication to adjust the first and second operational parameters such that the first and second operational parameters are brought closer to the first and second threshold values respectively. The indication may include recommended adjustments of the first and second operational parameters which are calculated such that the production rate of the system 1 (i.e. throughput of sealed containers) remains unchanged.

In the above embodiments, it has been described that the control unit 50 is configured to calculate an energy consumption per sealed tray, output an indication derived from the energy consumption per sealed tray, calculate a measure of energy efficiency based on the energy consumption per sealed tray and a threshold energy consumption per sealed tray, output an indication derived from the measure of energy efficiency (which may correspond to the indication derived from the energy consumption per sealed tray), and output a prompt based on the energy consumption per sealed tray and one or more operational parameters. However, it will be appreciated that, in alternative embodiments, the control unit 50 may instead be configured to output an indication derived from the power consumption, calculate a measure of power efficiency based on the power consumption and a threshold power consumption, output an indication derived from the measure of power efficiency (which may correspond to the indication derived from the power consumption per sealed tray), and output a prompt based on the power consumption and one or more operational parameters. That is, the electrical consumption may not be normalised based on the number of sealing operations per unit time, and the subsequent calculations instead may be directly based on the measured power consumption. In further embodiments, the electrical consumption may instead be normalised based on the number of production shifts per unit time or the number of production batches per unit time.

Claims

CLAIMS1. A sealing system for food containers, comprising: a frame; a conveyor system for conveying food containers through the sealing system, wherein the conveyor system is supported by the frame; a sealing unit configured to receive food containers from the conveyor system, wherein the sealing unit comprises a first sealing tool and a second sealing tool configured to be pressed together in order to seal each food container positioned therebetween, wherein the sealing unit is supported by the frame, and wherein the conveyor system is further configured to convey sealed food containers away from the sealing unit; a power monitoring unit configured to measure a power consumption of the sealing system; and a control unit configured to: calculate an energy consumption per sealed food container based on the power consumption and the number of sealing operations performed per unit time; and output an indication derived from the calculated energy consumption per sealed food container.
2. The sealing system of claim 1, wherein the control unit is further configured to: calculate a measure of energy efficiency of the sealing system based on a comparison of the energy consumption per sealed food container to a threshold energy consumption per sealed food container; and output an indication derived from the measure of energy efficiency, wherein the indication derived from the energy consumption per sealed food container comprises the indication derived from the measure of energy efficiency.
3. The sealing system of claim 2, further comprising a data storage device disposed within the sealing unit, wherein the threshold energy consumption is a predetermined threshold energy consumption, and wherein data indicative of the threshold energy consumption is stored within the data storage device.
4. The sealing system of claim 2, wherein the control unit is configured to receive data indicative of properties associated with the food containers to be sealed, and wherein the control unit is configured to determine the threshold energy consumption based on the properties associated with the food containers to be sealed.
5. The sealing system of claim 4, wherein the properties associated with the food containers to be sealed comprise one or more of: a sealing area of each food container; a sealing material for each food container; and a material of each food container
6. The sealing system of claim 2, wherein the control unit is configured to receive data indicative of the threshold energy consumption from an external computing device.
7. The sealing system of claim 6, wherein the external computing device is configured to receive energy consumption data from a plurality of other sealing systems for food containers, and wherein the threshold energy consumption is calculated based on the energy consumption data.
8. The sealing system of any of claims 1 to 7, wherein the control unit is further configured to: receive one or more operational parameters of the sealing system; and output a prompt to adjust the one or more operational parameters of the sealing system in response to determining that the energy consumption per sealed food container is greater than the threshold energy consumption per sealed food container or in response to determining that the energy consumption per sealed food container is less than the threshold energy consumption per sealed food container, and wherein the prompt is based on the energy consumption per sealed food container and the one or more operational parameters.
9. The sealing system of claim 8, wherein the control unit is configured to output the prompt to adjust the one or more operational parameters of the sealing system in response to determining that the energy consumption per sealed food container is greater than the threshold energy consumption per sealed food container by a first percentage of the threshold energy consumption per sealed food container.
10. The sealing system of claim 8 or claim 9, wherein the control unit is configured to output the prompt to adjust the one or more operational parameters of the sealing system in response to determining that the energy consumption per sealed food container is less than the threshold energy consumption per sealed food container by a second percentage of the threshold energy consumption per sealed food container.
11. The sealing system of any of claim 8 to 10, further comprising a strain gauge configured to measure a sealing force when the first sealing tool and the second sealing tool are pressed together, wherein the one or more operational parameters comprise the sealing force, and wherein the prompt comprises an indication to adjust the sealing force.
12. The sealing system of any of claims 8 to 11, further comprising a temperature sensor configured to measure a sealing temperature when the first sealing tool and the second sealing tool are pressed together, wherein the one or more operational parameters comprise the sealing temperature, and wherein the prompt comprises an indication to adjust the sealing temperature.
13. The sealing system of any of claims 8 to 12, wherein the one or more operational parameters comprise at least one of a speed of the conveyor system, a dwell time of the sealing unit, and a wait time of the sealing unit, and wherein the prompt comprises an indication to adjust at least one of the speed of the conveyor system, the dwell time of the sealing unit, and the wait time of the sealing unit.
14. The sealing system of any preceding claim, further comprising a display unit supported by the frame, wherein the control unit is configured to output the indication derived from the calculated energy consumption per sealed food container at the display unit.
15. The sealing system of any preceding claim, wherein the sealing unit is a heat-sealing tool configured to heat seal a film lid to the container along a sealed seam.
16. A sealing system for food containers, comprising: a frame; a conveyor system for conveying food containers through the sealing system, wherein the conveyor system is supported by the frame; a sealing unit configured to receive food containers from the conveyor system, wherein the sealing unit comprises a first sealing tool and a second sealing tool configured to be pressed together in order to seal each food container positioned therebetween, wherein the sealing unit is supported by the frame, and wherein the conveyor system is configured to convey sealed food containers away from the sealing unit; a power monitoring unit configured to measure a power consumption of the sealing system; and a control unit configured to: calculate a measure of power efficiency of the sealing system based on a comparison of the power consumption to a threshold power consumption; and output an indication derived from the measure of power efficiency of the sealing system.
17. A method of operating a food container sealing system, comprising: conveying, using a conveyor system, food containers to a sealing unit comprising a first sealing tool and a second sealing tool; pressing the first sealing tool and the second sealing tool together so as to seal each food container positioned therebetween; measuring, using a power monitoring unit, a power consumption of the sealing system; calculating, using a control unit, an energy consumption per sealed food 30 container based on the power consumption and the number of sealing operations performed per unit time; and outputting, using the control unit, an indication derived from the energy consumption per sealed food container.
18. The method of claim 17, performed using a system of any one of claims 1 to 15.