A control method of a food processor

Abstract

This invention relates to the field of kitchen cooking appliance technology. Existing methods for detecting and alerting about scale buildup in steam boilers of food processing machines are inaccurate. This invention provides a control method for a food processing machine, which includes a steam generating device. This control method is used to detect and alert about scale buildup in the boiler of the steam generating device, and includes the following steps: acquiring water quality detection data and equipment operating time for each boiler operation; converting the equipment operating time corresponding to the water quality into operating time under a calibrated water quality using a proportional conversion formula, and accumulating the calculated operating time each time; issuing a scale cleaning pre-alert when the accumulated operating time reaches the preset total operating time under the calibrated water quality; even when different water qualities are added to each boiler, the operating time can be converted to a uniform calibrated water quality for calculation, facilitating calculation and judgment, and improving the accuracy of scale detection.

Description

Technical Field

[0001] This invention relates to the field of kitchen cooking appliances technology, specifically to a control method for a food processing machine. Background Technology

[0002] With the widespread use of household appliances, the heating methods of existing kitchen cooking appliances have gradually become more diversified. For example, some microwave ovens and electric ovens have added steam as an auxiliary heating source. In this type of cooking appliance that uses steam as an auxiliary heating source, the steam is generated by the boiler of a steam generator and introduced into the food heating cavity through a steam pipe to assist microwaves or heating elements in heating food.

[0003] During operation, the surface temperature of the electric heating element in the boiler of the steam generator is very high, which makes it easy for scale to form. If the scale is not cleaned in time, the thermal conductivity of the electric heating element will deteriorate, and its surface temperature will rise rapidly during operation, causing damage to the electric heating element and posing a safety hazard.

[0004] Currently, most electrical appliances on the market use temperature sensors to detect boiler temperature and determine the presence of scale. However, because the location of scale formation is uncertain and the thickness varies in different areas, the placement of the temperature sensor affects the boiler temperature detection results. To improve accuracy, multiple temperature sensors are needed to detect the temperature at different locations on the boiler, which significantly increases the circuit cost and complexity of the equipment. Moreover, this solution only affects heat exchange efficiency and triggers an alarm when the scale is already quite thick. If the boiler is dry-burning, false alarms are very likely to occur. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the defects of the existing methods for detecting and reminding about scale in steam boilers of food processing machines, and to provide a control method for food processing machines for detecting and reminding about scale in steam boilers of food processing machines, which can improve the accuracy of scale detection.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: a control method for a food processing machine, the food processing machine including a steam generating device, the control method being used for detecting and alerting to scale buildup in the boiler of the steam generating device, comprising the following steps:

[0007] Obtain water quality test data and equipment operating time for each boiler run;

[0008] The equipment operating time corresponding to the water quality is converted into the operating time under the standard water quality according to the proportional conversion formula, and the operating time calculated each time is accumulated.

[0009] When the cumulative operating time reaches the preset total operating time under the specified water quality, a pre-reminder for scale cleaning will be issued.

[0010] A further preferred embodiment of the present invention is as follows: the water quality detection data during boiler operation includes TDS detection values; the calibration water quality is calibrated using TDS detection values; and the preset total operating time under the calibration water quality is obtained through multiple actual measurements and statistical analysis.

[0011] A further preferred embodiment of the present invention is that the calibration water quality is determined by the average value of TDS measurements during the first few runs of the boiler; or the calibration water quality is preset based on the average water quality of the region where the boiler is located.

[0012] A further preferred embodiment of the present invention is as follows: A geometrical conversion formula is used to transform the equipment operating time under different water qualities into the operating time under a calibrated water quality:

[0013] Y*Tn=Xn*tn*k;

[0014] Where Y is the reference value of the calibrated water quality; Xn is the water quality test data of the nth time during the operation of the boiler in a complete cumulative process, n≥1; tn is the equipment operation time under the water quality test value of Xn; Tn is the operation time converted to the calibrated water quality; where k is the compensation coefficient, 1≤k≤2.

[0015] A further preferred embodiment of the present invention is: the preset total operating time S under the calibrated water quality; the accumulated value of Tn is... when When the value is greater than or equal to S, a pre-warning reminder for limescale cleaning will be issued.

[0016] A further preferred embodiment of the present invention is: wherein

[0017] A further preferred embodiment of the present invention is as follows: the steps for obtaining the preset total operating time S under the calibrated water quality are as follows:

[0018] Step 1: Use a brand new, scale-free boiler to heat water with a test value of Y, and record the equipment's running time from the moment the equipment is started.

[0019] Step 2: After the water boils, continue heating. When the water level drops to the replenishment water level line, add water with a detection value of Y.

[0020] Step 3: Repeat step 2 until the scale produced reaches 1 mm. The total running time of the equipment in the above steps is S.

[0021] A further preferred embodiment of the present invention is that the reference value Y for calibrating water quality is ≥100.

[0022] A further preferred embodiment of the present invention is: during each operation of the boiler, the highest operating temperature B of the boiler is recorded;

[0023] The average of the peak temperatures during the first few runs of the new boiler is taken as the calibration temperature A.

[0024] Before issuing a pre-warning reminder for limescale cleaning, a false alarm check should be performed;

[0025] If the highest operating temperature B of the boiler is greater than or equal to A+C, a pre-warning will be issued; otherwise, it will be considered an error and the pre-warning will be cancelled. Here, C is the set tolerance.

[0026] A further preferred embodiment of the present invention includes resetting the accumulated operating time calculated for each scale removal to zero after each cleaning.

[0027] In summary, this invention offers the following advantages: By converting boiler operating times under different water qualities into corresponding equipment operating times under a unified calibrated water quality and accumulating the results, and comparing the accumulated results with the pre-obtained total equipment operating time for scale formation under that calibrated water quality, the scale situation within the boiler can be determined more accurately. Even when different water qualities are added to the boiler each time, the calculation can be converted to a unified calibrated water quality, facilitating judgment. Furthermore, double verification is performed by detecting the boiler temperature to ensure accurate scale detection and improve detection accuracy. Attached Figure Description

[0028] Figure 1 This is a flowchart of the control method for the food processing machine described in this invention. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0030] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0031] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0032] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0033] like Figure 1 The present invention provides a control method for a food processing machine, the food processing machine including a steam generating device. This control method is used for detecting and alerting about scale buildup in the boiler of the steam generating device, and mainly includes the following steps:

[0034] S1: Obtain water quality test data and equipment operating time for each boiler run;

[0035] S2: Convert the equipment operating time corresponding to the water quality into the operating time under the standard water quality according to the proportional conversion formula, and accumulate the operating time calculated each time.

[0036] S3: When the accumulated operating time reaches the preset total operating time under the calibrated water quality, a pre-reminder for scale cleaning will be issued;

[0037] S4: After each scale removal, the accumulated operating time calculated for each operation will be reset to zero.

[0038] The water quality testing data during boiler operation includes water hardness and TDS (Total Dissolved Solids) values. This water quality testing data should be related to scale formation. Water hardness, the sum of calcium and magnesium ion concentrations in water, is directly related to scale formation. TDS, the total amount of dissolved inorganic salts and organic matter in water, includes calcium and magnesium ions, and therefore is also related to scale to some extent. TDS testing is common and inexpensive; therefore, this invention uses TDS values ​​to indirectly reflect water hardness. However, this does not mean that water quality testing data is limited to TDS values. If cost is not a concern, other water quality data related to the causes of scale formation, such as water hardness, can also be used.

[0039] Therefore, in this embodiment, the TDS (Total Dissolved Solids) value is preferentially used to measure the water quality during boiler operation, and the corresponding calibration water quality is also calibrated using the TDS value. Specifically, the calibration water quality is determined by the average TDS value from the previous few boiler operations (or the calibration water quality is preset based on the average water quality of the region where the boiler is located).

[0040] Everyday water has a certain degree of hardness. When heating water with high hardness, insoluble salts of calcium and magnesium ions, such as calcium carbonate and magnesium carbonate, will precipitate out of the water and adhere to the inner surface of the kettle, forming scale. Therefore, the main reason for scale formation is that calcium and magnesium ions continuously precipitate and adhere to the boiler surface during equipment operation. Since the heating surface has the highest temperature, calcium and magnesium ions are more likely to precipitate near the heating surface.

[0041] Therefore, scale formation is related to water quality (i.e., calcium and magnesium ion concentration) and heating time. This invention, however, obtains the total operating time of the equipment when scale forms under a calibrated water quality beforehand. Then, it converts the operating time of the boiler under different water qualities each time it runs into the operating time under the calibrated water quality. By comparing the accumulated converted time with the pre-obtained total operating time of the equipment when scale forms under the calibrated water quality, the scale level inside the boiler can be determined more accurately.

[0042] Because the equipment operating time is converted into the equipment operating time under the calibrated water quality based on the water quality data each time the equipment runs, it can be converted into a uniform calibrated water quality each time different water quality is added to the boiler, which is convenient for calculation and judgment.

[0043] For specific conversion details, please refer to step S2. In step S2, the geometric conversion formula for converting equipment operating time under different water qualities to operating time under the calibrated water quality is as follows:

[0044] Y*Tn=Xn*tn*k;

[0045] Where Y is the reference value for calibrating water quality, satisfying That is, take the average of the first m Xn values ​​in the first ten Xn values;

[0046] Xn represents the water quality test data of the nth time during the operation of the boiler in a complete cumulative process, where n≥1;

[0047] tn represents the equipment operating time under the corresponding water quality test value Xn;

[0048] Tn represents the operating time converted to the standard water quality; k is the compensation coefficient, 1≤k≤2, generally k is set to 1. Since each descaling cycle cannot completely remove scale, the k value is used to compensate based on the amount of scale residue after different descaling methods; the amount of scale residue after different descaling methods is obtained through prior experiments. Generally, after two cleaning cycles, k can be set to 1.1.

[0049] The preset total operating time S under the calibrated water quality is set, and the accumulated value of Tn is...

[0050] Then when When the value is greater than or equal to S, a pre-warning reminder for limescale cleaning will be issued.

[0051] It should be noted that the preset total operating time S under the specified calibrated water quality was obtained through multiple actual measurements and statistical analysis. In obtaining the preset total operating time S under the specified calibrated water quality, the value of S differs depending on the reference value of Y selected. If the boiler uses pure water every time, since pure water does not contain calcium and magnesium ions, scale will not form, and therefore its S value should tend to infinity, which would be meaningless.

[0052] In most households, purified water is not readily available. Tap water is the most frequently used and easiest to obtain. According to the national standard GB5749-2006 "Standards for Drinking Water Quality", there is a limit on the total dissolved solids (TDS) of drinking tap water: ≤1000mg / L. However, in real life, the TDS value of tap water is mostly between 100-300. Therefore, the TDS value for water quality calibration in this invention is preferably 100.

[0053] When using water with a TDS value of 100 as the calibration water quality, its corresponding S value is relatively easy to measure (compared to values ​​less than 100), and the S value will not be too large. If a TDS value of 200 or 300 is used as the calibration water quality, the corresponding S value will be even smaller. However, as people's water quality awareness continues to improve, the quality of tap water is also constantly improving. The TDS value of water in most populated areas is relatively low. This invention uses calibration water with a TDS value of 100 as an example for illustration.

[0054] Select a TDS value of 100 as the calibration water quality, and obtain the corresponding preset total operating time S as follows:

[0055] Step 1: Use a brand new, scale-free boiler to heat water with a TDS value of 100, and record the equipment's running time from the moment the equipment is started.

[0056] Step 2: After the water boils, continue heating, generating steam and releasing it while continuously replenishing the steam generator boiler with water from the water tank. When the water level in the tank drops to the replenishment water level line, add water with a detection value of Y. During this process, the equipment remains in operation.

[0057] Step 3: Repeat Step 2 until the scale buildup reaches 1 mm. The total running time of the equipment in the above steps is measured in seconds (S). For ease of measurement, an observation hole will be made on the steam generator, with a high-temperature resistant glass window installed in the observation hole to observe the scale growth on the heated surface.

[0058] The boiler's heat transfer efficiency decreases as scale thickness increases, and the thickest scale is often found on the boiler's heating surface. Therefore, it's sufficient to check the scale thickness on the heating surface. To ensure stable boiler operation, users should be promptly alerted to clean the scale when it reaches 1mm. Of course, the required scale thickness for alerting can be adjusted depending on the size of the steam-generating boiler.

[0059] Because scale affects the heat exchange efficiency between the boiler and water, once scale is present in the boiler, it will reduce the heat exchange efficiency at the heating surface, resulting in the boiler temperature when the water boils being higher than the boiler temperature when there is no scale.

[0060] Therefore, during each boiler operation, the highest operating temperature B of the boiler is recorded;

[0061] The average of the peak temperatures during the first few runs of the new boiler is taken as the calibration temperature A.

[0062] Before issuing a pre-warning for limescale cleaning, the system uses data from B and A to determine if a warning is false.

[0063] If the highest operating temperature B of the boiler is greater than or equal to A+C, a pre-alert will be issued; otherwise, it will be considered an error and the pre-alert will be cancelled. Here, C is the set tolerance, typically set to 10 degrees Celsius. By combining boiler temperature and water quality monitoring, cross-verification can be achieved. This not only detects whether there is water in the boiler, effectively preventing false alarms caused by scale buildup during dry burning, but also greatly improves the reliability and accuracy of the equipment.

Claims

1. A control method of a food processor including a steam generating device, for scale detection and alerting of a boiler in the steam generating device, characterized in that, Includes the following steps: Obtain water quality test data and equipment operating time for each boiler run; The equipment operating time corresponding to the water quality is converted into the operating time under the standard water quality according to the proportional conversion formula, and the operating time calculated each time is accumulated. When the cumulative operating time reaches the preset total operating time under the specified water quality, a pre-reminder for scale cleaning will be issued; The proportional conversion formula for transforming equipment operating time under different water qualities into operating time under calibrated water quality is: Y*Tn=Xn*tn*k; where Y is the reference value of the calibrated water quality; Xn is the water quality test data of the nth time during a complete cumulative process of boiler operation, n≥1; tn is the equipment operating time under the water quality test value Xn; Tn is the operating time converted from tn to the calibrated water quality; and k is the compensation coefficient, with a value of 1. The steps for obtaining the preset total operating time S under the calibrated water quality are as follows: Step 1: Use a brand new, scale-free boiler to heat water with a test value of Y, and record the equipment's running time from the moment the equipment is started. Step 2: After the water boils, continue heating. When the water level drops to the replenishment water level line, add water with a detection value of Y. Step 3: Repeat step 2 until the scale produced reaches 1 mm. The total running time of the equipment in the above steps is S.

2. The control method of the food processor according to claim 1, characterized in that, The water quality detection data during boiler operation includes TSD detection values; the calibrated water quality is determined using TSD detection values; and the preset total operating time under the calibrated water quality is obtained through multiple actual measurements and statistical analysis.

3. The control method for a food processing machine according to claim 2, characterized in that, The calibration water quality is preset based on the average water quality of the area where the boiler is located.

4. The control method for a food processing machine according to claim 1, characterized in that, The preset total operating time S under the calibrated water quality; the accumulated value of Tn, when it is greater than or equal to S, will issue a pre-reminder for scale cleaning.

5. The control method for a food processing machine according to claim 1, characterized in that, The reference value for calibrated water quality is Y≥100.

6. The control method for a food processing machine according to claim 2, characterized in that, During each boiler operation, record the highest operating temperature B; take the average of the temperature peaks during the first few operations of the new boiler as the calibration temperature A. Before issuing a pre-warning for scale cleaning, a false alarm check is performed; if the highest operating temperature of the boiler B ≥ A + C, a pre-warning is issued; otherwise, it is considered an error and the pre-warning is canceled; where C is the set tolerance.

7. The control method for a food processing machine according to claim 1, characterized in that, This also includes resetting the accumulated operating time calculated for each scale removal to zero after each cleaning.

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