Electronic scale and four-corner compensation method thereof

Abstract

The present application provides an electronic scale and a four-corner compensation method thereof, relating to the technical field of electronic scales. First, the output electromotive force of four groups of sensors in the electronic scale is obtained when they are loaded with the same load. Then, based on the output electromotive force, a compensation resistor is connected in parallel or in series at both ends of at least one group of sensors. The resistance value of the compensation resistor is then determined based on the output electromotive force so that the output electromotive force of the four groups of sensors is the same when loaded with the same load. The electronic scale and the four-corner compensation method provided by the present application have the advantage of improving the weighing accuracy of the electronic scale.

Description

Technical Field

[0001] The present application relates to the technical field of electronic scales, and in particular to an electronic scale and a four-corner compensation method thereof. Background Art

[0002] Electronic body scales / kitchen scales use four steel sensor plates, mounted at the four corners of the square scale body. To ensure consistent weighing results regardless of the person's position on the scale, the scale's four-corner error must be less than a specified value. This means that when weights are applied to each of the four corners, the difference in the scale's output (display) must be less than a specified value.

[0003] The traditional method for controlling the four-corner error of electronic body scales / kitchen scales is the so-called "grouping method," which involves applying the same load to each steel sensor on a dedicated loading device, measuring its output value, and then grouping sensors with the same or similar output values ​​and installing them on an electronic body scale / kitchen scale.

[0004] Due to the high production volume and fast production cycle of electronic body scale / kitchen scale sensors, multiple test stations are required to conduct simultaneous tests during grouping. The sensor cable needs to be inserted into the wire clamp socket, and the contact resistance between the socket and the wire will randomly change, thereby changing the supply voltage on the sensor bridge circuit and causing measurement errors. The contact state between the sensor support surface and the loading platform will vary with the flatness and roughness of different test stations, causing changes in the boundary conditions of the force on the sensor, resulting in measurement errors. In particular, the structure of the steel sheet sensor itself determines that its output is very sensitive to the loading point. Therefore, if the loading points of different test stations are different, or even if the loading points of the same test station are different each time, measurement errors will occur, resulting in large errors in the sensors at the four corners after the electronic scale is assembled.

[0005] In summary, the prior art has the problem that after the electronic scale is assembled, the sensors at the four corners have large errors. Summary of the Invention

[0006] The purpose of the present application is to provide an electronic scale and a four-corner compensation method thereof, so as to solve the problem in the prior art that the sensors at the four corners of the electronic scale have large errors after assembly.

[0007] In order to achieve the above objectives, the technical solutions adopted in the embodiments of the present application are as follows:

[0008] In one aspect, an embodiment of the present application provides a method for compensating for four corners of an electronic scale, the method comprising:

[0009] Obtain the output electromotive force of the four groups of sensors of the electronic scale when they are loaded with the same load;

[0010] Connecting compensation resistors in parallel or in series at both ends of at least one set of sensors based on the output electromotive force;

[0011] The resistance value of the compensation resistor is determined based on the output electromotive force, so that the output electromotive forces of the four groups of sensors are the same when the same load is applied.

[0012] Optionally, the output electromotive force satisfies the formula:

[0013]

[0014] Among them, V ic represents the output electromotive force of the i-th group of sensors, E i It represents the sensor electromotive force of the i-th group of sensors, and the sensor electromotive force is proportional to the sensor sensitivity.

[0015] Optionally, the output electromotive force after connecting the compensation resistor in parallel satisfies the formula:

[0016]

[0017] Among them, V' ic It represents the output electromotive force of the i-th group of sensors after parallel compensation resistance, Q i represents the resistance of the compensation resistor of the i-th group of sensors, P i represents the resistance of the peripheral resistor of the i-th group of sensors, 2R represents the internal resistance of the sensor, E i It represents the sensor electromotive force of the i-th group of sensors, and the sensor electromotive force is proportional to the sensor sensitivity.

[0018] Optionally, the step of connecting compensation resistors in parallel or in series at both ends of at least one group of sensors based on the output electromotive force includes:

[0019] Determine a set of sensors that minimizes the output electromotive force;

[0020] Connect the remaining three groups of sensors in parallel with compensation resistors.

[0021] Optionally, after connecting the compensation resistors in parallel, the output electromotive force of each sensor group satisfies the formula:

[0022] V′ 1c =V′ 2c

[0023] V′ 1c =V′ 3c

[0024] V′ 1c =V′ 4c

[0025] Among them, V' 1cRepresents the output electromotive force of the first group of sensors, and the first group of sensors is the group of sensors with the smallest output electromotive force before the compensation resistor is connected in parallel, V' 2c Represents the output electromotive force of the second set of sensors after the parallel compensation resistor is connected, V' 3c Represents the output electromotive force of the third group of sensors after the parallel compensation resistor is connected, V' 4c It represents the output electromotive force of the fourth group of sensors after the compensation resistor is connected in parallel.

[0026] On the other hand, an embodiment of the present application further provides an electronic scale, which uses the above method for compensation, and the electronic scale includes:

[0027] Weigh the body;

[0028] Four groups of sensors, the four groups of sensors are located at the four corners of the scale body, and the four groups of sensors are interconnected to form a Wheatstone bridge;

[0029] At least one compensation resistor is connected in parallel with two ends of the sensor, so that the output electromotive force of the four groups of sensors is the same when the same load is applied.

[0030] Optionally, there are three compensation resistors, and the three compensation resistors are respectively connected in parallel with three groups of target sensors, wherein when the four groups of sensors are loaded with the same load, the three groups of sensors that output the largest electromotive force are used as target sensors.

[0031] Optionally, after connecting the compensation resistors in parallel, the output electromotive force of each sensor group satisfies the formula:

[0032] V′ 1c =V′ 2c

[0033] V′ 1c =V′ 3c

[0034] V′ 1c =V′ 4c

[0035] Among them, V' 1c Represents the output electromotive force of the first group of sensors, and the first group of sensors is the group of sensors with the smallest output electromotive force before the compensation resistor is connected in parallel, V' 2c Represents the output electromotive force of the second set of sensors after the parallel compensation resistor is connected, V' 3c Represents the output electromotive force of the third group of sensors after the parallel compensation resistor is connected, V' 4c It represents the output electromotive force of the fourth group of sensors after the compensation resistor is connected in parallel.

[0036] Optionally, each group of sensors includes a first strain gauge located in the tensile strain zone and a second strain gauge located in the compressive strain zone, and in the Wheatstone bridge, two first strain gauges or two second strain gauges from two adjacent groups of sensors are connected in series on the same bridge arm.

[0037] Optionally, the output electromotive force after connecting the compensation resistor in parallel satisfies the formula:

[0038]

[0039] Among them, V' ic It represents the output electromotive force of the i-th group of sensors after parallel compensation resistance, Q i represents the resistance of the compensation resistor of the i-th group of sensors, P i represents the resistance of the peripheral resistor of the i-th group of sensors, 2R represents the internal resistance of the sensor, E i It represents the sensor electromotive force of the i-th group of sensors, and the sensor electromotive force is proportional to the sensor sensitivity.

[0040] Compared with the prior art, this application has the following beneficial effects:

[0041] The embodiment of the present application provides an electronic scale and a four-corner compensation method thereof. First, the output electromotive force of the four groups of sensors of the electronic scale when they are loaded with the same load is obtained. Then, based on the output electromotive force, compensation resistors are connected in parallel or in series at both ends of at least one group of sensors. Then, the resistance value of the compensation resistor is determined based on the output electromotive force so that the output electromotive force of the four groups of sensors when they are loaded with the same load is the same. On the one hand, since the present application uses compensation resistors to compensate the sensors, the accuracy of the electronic scale can be guaranteed to be higher. On the other hand, since the four groups of sensors have been installed on the scale body and the sensor wires have been welded to the group bridge plate before setting the compensation resistors, the four sensors are loaded and tested respectively, and then the four corner errors are adjusted to within the tolerance range by welding the compensation resistors. Since the circuit conditions and force conditions are the same as the actual use conditions, the errors caused by testing the sensors separately are avoided, so that the weighing accuracy is guaranteed.

[0042] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0044] Figure 1 Schematic diagram of the circuit of an electronic scale in the prior art.

[0045] Figure 2 This is an exemplary flow chart of the four-corner compensation method for an electronic scale provided in an embodiment of the present application.

[0046] Figure 3 Schematic diagram of the equivalent circuit of the electronic scale provided in an embodiment of the present application.

[0047] Figure 4 Another equivalent circuit diagram of the electronic scale provided in an embodiment of the present application.

[0048] Figure 5 Schematic diagram of the equivalent circuit of the electronic scale after compensating the parallel resistance provided in an embodiment of the present application.

[0049] Figure 6 Another exemplary flow chart of the four-corner compensation method for an electronic scale provided in an embodiment of the present application. DETAILED DESCRIPTION

[0050] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0051] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in the present application without creative work are within the scope of protection of the present application.

[0052] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and should not be understood as indicating or implying relative importance.

[0053] It should be noted that, in this document, relational terms such as first and second, etc. are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0054] The following describes some embodiments of the present application in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features therein may be combined with each other.

[0055] like Figure 1 As shown, the scale consists of four sensors: LC1, LC2, LC3, and LC4. Each sensor has two strain gauges: one attached to the tensile strain gauge area (e.g., SR1+, SR2+, SR3+, SR4+), and the other attached to the compressive strain gauge area (e.g., SR1-, SR2-, SR3-, SR4-). The four sensors are welded together as shown to form a Wheatstone bridge, also known as the measuring bridge for a scale. This bridge is characterized by a series connection of strain gauges with the same sign from two adjacent sensors on one arm. EX+ and EX- are connected to the positive and negative terminals of the excitation power supply, respectively, while SIG+ and SIG- output the weighing voltage signal.

[0056] Typically, when there's no load, all strain gauges have the same resistance, denoted by R. When a load is applied, the resistance of the strain gauge changes proportionally to the load. The resistance of the strain gauge in the tensile strain zone increases, while the resistance of the strain gauge in the compressive strain zone decreases. Assuming the bridge excitation voltage (i.e., the voltage between Ex+ and Ex-) is 1V, the output voltage of the measuring bridge is:

[0057]

[0058] Where: r is 、r ic Respectively represent the change in resistance of SRi+ and SRi- when loading, i = 1, 2, 3, 4. In general, the tensile and compressive strains on the same sensor are basically equal, so it can be considered that r is =r ic =r i , considering that R is much larger than r i , under general accuracy conditions, the above formula can be simplified to:

[0059]

[0060] Assume that the relationship between the resistance change of the strain gauge on the sensor and the load it bears is:

[0061] r i =F i k i

[0062] i=1,2,3,4. Among them, F i is the load on the i-th sensor, k i is the change in strain gauge resistance of the i-th sensor under unit load, hereinafter referred to as the sensitivity coefficient.

[0063] If the total load F of the whole scale remains unchanged, different loading positions only result in different loads distributed to the four sensors, that is,

[0064] F=F1+F2+F3+F3

[0065] Then the above formula

[0066]

[0067] can be written as:

[0068]

[0069] If you want to ensure that the output of the bridge is equal under any combination of F1, F2, F3, and F4, that is, the bridge output is independent of the loading position, you must ensure that

[0070] k1=k2=k3=k4=k

[0071] That is, the sensitivity coefficients of the four sensors must be equal.

[0072] However, as described in the background technology, when the sensors are grouped and tested, the contact resistance between the socket and the wire will change randomly, thereby changing the power supply voltage on the sensor bridge circuit and causing measurement errors; and the contact state between the sensor support surface and the loading platform will vary with the flatness and roughness of different test stations, resulting in changes in the boundary conditions of the force on the sensor, thereby generating measurement errors; in addition, the structure of the steel sheet sensor itself determines that its output is very sensitive to the loading point. Therefore, if the loading points of different test stations are different, or even if the loading points of the same test station are different each time it is loaded, measurement errors will occur.

[0073] Therefore, the sensitivity of a group of sensors measured on the grouping machine may change after being assembled on the actual scale body. The sensitivities of the four sensors are no longer equal or similar. Therefore, after the electronic scale is assembled, the errors of the sensors at the four corners may be large, resulting in lower weighing accuracy of the electronic scale.

[0074] In view of this, an embodiment of the present application provides a four-corner compensation method for an electronic scale, which improves the weighing accuracy of the electronic scale by installing four groups of sensors on the scale body and then using compensation resistors for compensation.

[0075] The following is an exemplary description of the four-corner compensation method for an electronic scale provided by this application:

[0076] As an optional implementation, see Figure 2 , the electronic scale four-corner compensation method includes:

[0077] S102, obtaining the output electromotive force of the four groups of sensors of the electronic scale when they are loaded with the same load.

[0078] S104 , connecting compensation resistors in parallel or in series at both ends of at least one group of sensors based on the output electromotive force.

[0079] S106 , determining the resistance of the compensation resistor based on the output electromotive force, so that the output electromotive force of the four groups of sensors is the same when the same load is applied.

[0080] On the one hand, since the present application utilizes compensation resistors to compensate the sensors, the accuracy of the electronic scale can be guaranteed to be higher. On the other hand, since the four groups of sensors have been installed on the scale body and the sensor wires have been welded to the bridge plate before setting the compensation resistors, the four sensors are loaded and tested separately, and then the four corner errors are adjusted to within the tolerance range by welding the compensation resistors. Since the circuit conditions and force conditions are the same as the actual use conditions, the errors caused by testing the sensors separately are avoided, so that the weighing accuracy is guaranteed. In addition, the four-corner compensation method for electronic scales provided by the present application is also more convenient to achieve full automation, reduce labor, and improve economic benefits.

[0081] It should be noted that, according to the circuit signal principle, the loaded sensor can be regarded as a series connection of a voltage source and an internal resistance, such as Figure 3 As shown, the voltage source has an electromotive force of E and an internal resistance of 2R. When the voltage source is combined with three other unloaded sensors to form a bridge, it is equivalent to the voltage source carrying an external load. The output Vc of the entire bridge is actually the voltage divider of the electromotive force E of the sensor. Obviously:

[0082]

[0083] When the same load is applied to four sensors separately, four output values ​​can be obtained.

[0084]

[0085] Among them, V ic represents the output electromotive force of the i-th group of sensors, E i It represents the sensor electromotive force of the i-th group of sensors, and the sensor electromotive force is proportional to the sensor sensitivity.

[0086] The electromotive force E of each sensor can be calculated by the above test. i It should be noted that the present application does not limit the value of the same load. For example, the load value can be 100g or 1000g. It only needs to ensure that the load values ​​are equal when obtaining the output electromotive force of the four sets of sensors.

[0087] In practical applications, the load can be a weight, for example, a 1000g weight. First, the weight is placed on the first corner of the electronic scale, and the output electromotive force at this time can be obtained; then the weight is placed on the second corner of the electronic scale, and the output electromotive force at this time is continued to be obtained, and so on, and the electromotive forces corresponding to the four groups of sensors are obtained.

[0088] Then, a compensation resistor Q is connected in parallel at both ends of the sensor, such as Figure 4 As shown, if we consider that other sensors are also connected in parallel with resistors, the peripheral resistance has changed, and the peripheral resistance is represented by P. Then the output electromotive force after the parallel compensation resistor satisfies the formula:

[0089]

[0090] Among them, V' ic It represents the output electromotive force of the i-th group of sensors after parallel compensation resistance, Q i represents the resistance of the compensation resistor of the i-th group of sensors, P i represents the resistance of the peripheral resistor of the i-th group of sensors, 2R represents the internal resistance of the sensor, E i It represents the sensor electromotive force of the i-th group of sensors, and the sensor electromotive force is proportional to the sensor sensitivity.

[0091] In one implementation, since the output of the angle is always reduced after the parallel compensation resistor Q is connected, it is only necessary to connect the compensation resistor in parallel to the three sensors with large output. The circuit after the parallel compensation resistor is as follows Figure 5 shown.

[0092] On this basis, see Figure 6 , S104 includes:

[0093] S1041, determining a group of sensors with the smallest output electromotive force;

[0094] S1042, connect the compensation resistors in parallel to the remaining three groups of sensors.

[0095] Moreover, after the compensation resistors are connected in parallel, the output electromotive force of each sensor group satisfies the formula:

[0096] V′ 1c =V′ 2c

[0097] V′ 1c =V′ 3c

[0098] V′ 1c =V′ 4c

[0099] Among them, V' 1cRepresents the output electromotive force of the first group of sensors, and the first group of sensors is the group of sensors with the smallest output electromotive force before the compensation resistor is connected in parallel, V' 2c Represents the output electromotive force of the second set of sensors after the parallel compensation resistor is connected, V' 3c Represents the output electromotive force of the third group of sensors after the parallel compensation resistor is connected, V' 4c It represents the output electromotive force of the fourth group of sensors after the compensation resistor is connected in parallel.

[0100] The output electromotive force of each sensor is combined with this set of equations

[0101]

[0102] The resistance of the three compensation resistors in parallel can be calculated.

[0103] The four-corner compensation method described above for electronic scales compensates for all four sensor groups, ensuring they produce the same output electromotive force when loaded with the same load. Furthermore, because the four-corner angular difference test is performed after the scale is installed, the results include differences in sensor sensitivity, scale installation and loading conditions, and the impedance of the sensor connections. Consequently, the compensation results are ideal.

[0104] Of course, it should also be noted that this application does not limit the number of compensation resistors connected in parallel or in series. For example, the compensation resistors can be set to four or more, and different compensation resistors are connected in parallel or in series at both ends of each group of sensors. When the four groups of sensors are connected to the compensation resistors, the output electromotive force is reduced, but the output electromotive force is the same. Alternatively, if the output electromotive force of three groups of sensors is basically the same, and the output electromotive force of another group of sensors is higher, it may be sufficient to only connect the compensation resistors in parallel or in series with the group of sensors. Of course, there may also be two compensation resistors, which will not be elaborated here.

[0105] Based on the above implementation, an embodiment of the present application further provides an electronic scale, which uses the above method for compensation, and includes:

[0106] a weighing body; four groups of sensors, the four groups of sensors are located at the four corners of the weighing body, and the four groups of sensors are interconnected to form a Wheatstone bridge; at least one compensation resistor, the compensation resistor is connected in parallel with both ends of the sensor, so that the output electromotive force of the four groups of sensors is the same when the same load is applied.

[0107] As an implementation method, the number of compensation resistors includes multiple combinations, and the compensation resistors are connected in parallel with the target sensors respectively. Among them, when the four groups of sensors are loaded with the same load, the three groups of sensors with the largest output electromotive force are used as target sensors.

[0108] When the number of compensation resistors is three, the output electromotive force of each group of sensors after the compensation resistors are connected in parallel satisfies the formula:

[0109] V′ 1c =V′ 2c

[0110] V′ 1c =V′ 3c

[0111] V′ 1c =V′ 4c

[0112] Among them, V' 1c Represents the output electromotive force of the first group of sensors, and the first group of sensors is the group of sensors with the smallest output electromotive force before the parallel compensation resistor is connected, V' 2c Represents the output electromotive force of the second set of sensors after the parallel compensation resistor is connected, V' 3c Represents the output electromotive force of the third group of sensors after the parallel compensation resistor is connected, V' 4c It represents the output electromotive force of the fourth group of sensors after the compensation resistor is connected in parallel.

[0113] In addition, if Figure 5 As shown, each group of sensors includes a first strain gauge located in the tensile strain region and a second strain gauge located in the compressive strain region, and in the Wheatstone bridge, two first strain gauges or two second strain gauges from two adjacent groups of sensors are connected in series on the same bridge arm.

[0114] Optionally, the output electromotive force after connecting the compensation resistor in parallel satisfies the formula:

[0115]

[0116] Among them, V' ic It represents the output electromotive force of the i-th group of sensors after parallel compensation resistance, Q i represents the resistance of the compensation resistor of the i-th group of sensors, P i represents the resistance of the peripheral resistor of the i-th group of sensors, 2R represents the internal resistance of the sensor, E i It represents the sensor electromotive force of the i-th group of sensors, and the sensor electromotive force is proportional to the sensor sensitivity.

[0117] In summary, the embodiment of the present application provides an electronic scale and a four-corner compensation method thereof. First, the output electromotive force of the four groups of sensors of the electronic scale when they are loaded with the same load is obtained. Then, based on the output electromotive force, compensation resistors are connected in parallel or in series at both ends of at least one group of sensors. Then, the resistance value of the compensation resistor is determined based on the output electromotive force so that the output electromotive force of the four groups of sensors when they are loaded with the same load is the same. On the one hand, since the present application uses compensation resistors to compensate the sensors, the accuracy of the electronic scale can be guaranteed to be higher. On the other hand, since the four groups of sensors have been installed on the scale body and the sensor wires have been welded to the group bridge plate before setting the compensation resistors, the four sensors are loaded and tested respectively, and then the four corner errors are adjusted to within the tolerance range by welding the compensation resistors. Since the circuit conditions and force conditions are the same as the actual use conditions, the errors caused by testing the sensors separately are avoided, so that the weighing accuracy is guaranteed.

[0118] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

[0119] It will be apparent to those skilled in the art that the present application is not limited to the details of the exemplary embodiments described above and that the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present application is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A four-corner compensation method for an electronic scale, characterized in that: The method comprises: Obtaining the output electromotive force of each of the four groups of sensors of the assembled electronic scale when loaded with the same load; wherein the four groups of sensors are interconnected to form a Wheatstone bridge, each group of sensors including a first strain gauge located in a tensile strain region and a second strain gauge located in a compressive strain region, and wherein two first strain gauges or two second strain gauges from two adjacent groups of sensors are connected in series on the same bridge arm of the Wheatstone bridge; Determine a set of sensors that minimizes the output electromotive force; Connect the compensation resistors in parallel to the remaining three groups of sensors; Determining the resistance of the compensation resistor based on the output electromotive force so that the output electromotive forces of the four groups of sensors are the same when the same load is applied; The output electromotive force satisfies the formula: Among them, V ic represents the output electromotive force of the i-th group of sensors, E i represents the sensor electromotive force of the i-th group of sensors, and the sensor electromotive force is proportional to the sensor sensitivity; The output electromotive force after parallel compensation resistance satisfies the formula: in, It represents the output electromotive force of the i-th group of sensors after the parallel compensation resistor is connected, Q i Indicates the resistance of the compensation resistor of the i-th group of sensors, P i represents the resistance of the peripheral resistor of the i-th group of sensors, 2R represents the internal resistance of the sensor, E i It represents the sensor electromotive force of the i-th group of sensors, and the sensor electromotive force is proportional to the sensor sensitivity.

2. The electronic scale four-corner compensation method according to claim 1, characterized in that: After the compensation resistors are connected in parallel, the output electromotive force of each sensor group satisfies the formula: in, represents the output electromotive force of the first group of sensors, and the first group of sensors is the group of sensors with the smallest output electromotive force before the compensation resistor is connected in parallel. It represents the output electromotive force of the second set of sensors after the compensation resistor is connected in parallel. It represents the output electromotive force of the third group of sensors after the compensation resistor is connected in parallel. It represents the output electromotive force of the fourth group of sensors after the compensation resistor is connected in parallel.

3. An electronic scale, characterized in that: The electronic scale is compensated using the method according to claim 1 or 2, and the electronic scale comprises: Weigh the body; Four groups of sensors, the four groups of sensors are located at the four corners of the scale body, and the four groups of sensors are interconnected to form a Wheatstone bridge; At least one compensation resistor is connected in parallel with two ends of the sensor, so that the output electromotive force of the four groups of sensors is the same when the same load is applied.

4. The electronic scale according to claim 3, wherein: The number of the compensation resistors includes three, and the three compensation resistors are respectively connected in parallel with the three groups of target sensors. When the four groups of sensors are loaded with the same load, the three groups of sensors that output the largest electromotive force are used as target sensors.

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