Automatic compensation device and method suitable for weighing rod

Abstract

The invention relates to an automatic compensation device and method suitable for a weighing rod, and the device comprises a traction mechanism, a target weighing rod is disposed on the traction mechanism, and the traction mechanism is used for carrying out the traction of the target weighing rod, so as to enable the target weighing rod to carry out the preset displacement; the hydraulic force measuring machine is provided with a force application unit, and the hydraulic force measuring machine is used for applying a preset pressure value to the at least one weighing sensor of the target weighing rod through the force application unit; the controller is respectively connected with and controls the traction mechanism, the hydraulic force measuring machine and the force applying unit; and the controller controls the traction mechanism to enable the target weighing rod to perform at least one preset displacement, so that the single weighing sensor on the target weighing rod corresponds to the force application unit of the hydraulic force measuring machine. According to the weighing rod, the technical problem that the operation is difficult when each weighing sensor of the weighing rod is adjusted and compensated due to the fact that adjacent weighing sensors of an existing weighing rod influence each other and the weight of the weighing rod is heavy is solved.

Description

Technical Field

[0001] This application relates to the technical field of resistive strain load cells, and specifically relates to an automatic compensation device and method suitable for weighing bars. Background Art

[0002] With the continuous deepening of the work of governing overloaded trucks, different forms of dynamic highway vehicle weighbridges are constantly updated. Products such as axle load type, axle group type, vehicle type, bending plate type, quartz type, narrow strip type, etc. have emerged continuously. In recent years, with the continuous development and improvement of the non-stop over-limit detection non-site law enforcement system, strip-shaped load cells embedded in the road surface have gradually gained the favor of the using departments and the demand is increasing. Compared with the scale platform products, the strip-shaped load cell has a small cross-sectional size, can be directly installed by cutting grooves, has a small project volume and a short construction period, and has obvious advantages.

[0003] Chinese Patent with the publication number CN214667165U discloses a strip array weighing bar, which is composed of multiple sub-strain structure units arranged in an array; among them, the sub-strain structure unit is composed of any one or a mixed array of two of a cantilever beam strain structure, a double shear beam strain structure, a parallel bending beam strain structure, and a normal stress strain structure. By arraying the sub-strain structures, a strip array weighing bar is obtained, and the number of sub-strain structure units can be flexibly adjusted to obtain weighing sensors of different length specifications. Its integrated structure also effectively solves the fundamental problem of sealing and waterproofing, achieving the effect of maintenance-free.

[0004] Therefore, at present, domestic high-speed pre-inspection weighing systems, entrance over-limit control weighing systems, and non-site law enforcement systems all need to accurately weigh various trucks. Weighing bar products are widely used in these occasions. Because weighing bar products have the characteristics of simple installation, maintenance-free, and long service life, they are very suitable for the above systems. The weighing bar is mainly composed of multiple load cells combined. The multiple load cells are both related and independent of each other, which puts forward very high technological requirements for the production of weighing bars. It is necessary to adjust and compensate the multiple load cells many times to ensure that the sensitivity, linearity, and mutual influence of each load cell are consistent, and finally meet the overall measurement performance and accuracy of the overall weighing bar. Among them, the weighing bar is heavy and difficult to move. Multiple adjustments and compensations are very troublesome. At present, some enterprises rely on manual movement and manual calculation methods to adjust, which is inefficient, inaccurate, and has poor consistency. Now, an automatic compensation method suitable for weighing bars is proposed to realize automatic traction movement, automatic calculation, and automatic comparison of weighing bars, and finally meet the measurement accuracy requirements. Summary of the Invention

[0005] This application mainly solves the technical problem that it is difficult to operate when adjusting and compensating each weighing sensor of the weighing rod because adjacent weighing sensors will affect each other and the weighing rod is relatively heavy.

[0006] In an embodiment of this application, an automatic compensation device adapted to a weighing rod is provided, which is used to perform adjustment and compensation tests on the weighing accuracy of a target weighing rod. The target weighing rod includes at least one weighing sensor arranged in parallel. The automatic compensation device includes:

[0007] A traction mechanism, on which the target weighing rod is arranged. The traction mechanism is used to traction the target weighing rod so that the target weighing rod performs a preset displacement;

[0008] A hydraulic dynamometer, on which a force application unit is arranged. The hydraulic dynamometer is used to apply a preset pressure value to at least one weighing sensor of the target weighing rod through the force application unit;

[0009] A controller, which is respectively connected to and controls the traction mechanism, the hydraulic dynamometer and the force application unit;

[0010] The controller controls the traction mechanism to make the target weighing rod perform at least one preset displacement, so that a single weighing sensor on the target weighing rod corresponds to the force application unit of the hydraulic dynamometer;

[0011] When there is a weighing sensor on the target weighing rod corresponding to the force application unit of the hydraulic dynamometer, the controller controls the hydraulic dynamometer to apply a preset pressure value to the current weighing sensor on the target weighing rod corresponding to the force application unit through the force application unit.

[0012] In the above automatic compensation device adapted to a weighing rod, as a preferred solution, the automatic compensation device further includes a processor and a resistance automatic compensator;

[0013] The resistance automatic compensator is connected to the target weighing rod and is used to obtain the actual weighing result of the resistance automatic compensator;

[0014] The processor is connected to the controller and is used to set a preset displacement and / or a preset pressure value through the controller;

[0015] The processor is also connected to the target weighing rod through the resistance automatic compensator. The processor calculates and obtains a compensation resistance value according to the actual weighing result and the preset pressure value.

[0016] In the above automatic compensation device adapted to a weighing rod, as a preferred solution, the traction mechanism includes a power source, a ball screw, a rotating nut, a balance guide rail, a first slider and a first connecting plate;

[0017] The control end of the power source is connected to the controller, the output end of the power source is connected to the ball screw, the rotating nut is threadedly connected to the ball screw, the balance guide rail is fixedly arranged in parallel with the ball screw, one end of the first slider is slidably connected to the balance guide rail, and the other end is fixedly connected to the rotating nut. The first connecting plate is fixedly arranged on the first slider, and the target weighing rod is installed on the first connecting plate.

[0018] In the above-mentioned weighing rod automatic compensation device, as a preferred solution, the power source includes a servo motor and a shaft connector. The servo motor is connected to the ball screw through the shaft connector, and the control end of the servo motor is connected to the controller;

[0019] Left and right bearing seats are respectively arranged at both ends of the ball screw.

[0020] In the above-mentioned weighing rod automatic compensation device, as a preferred solution, there are two balance guide rails, which are symmetrically arranged on both sides of the ball screw respectively;

[0021] The traction mechanism further includes a second slider, a third slider and a third connecting plate;

[0022] The second slider is fixedly connected to the rotating nut, and the second slider is symmetrically arranged with the first slider and slidably connected to the balance guide rail on the opposite side of the first slider;

[0023] The third slider is arranged on the same side of the first slider. The third slider is slidably connected to the balance guide rail. The third connecting plate is fixedly connected to the third slider, and the target weighing rod is installed on the first connecting plate and the third connecting plate.

[0024] In the above-mentioned weighing rod automatic compensation device, as a preferred solution, the hydraulic dynamometer includes a dynamometer support and a hydraulic cylinder, and the force application unit includes a pressure block, an electromagnet and a force application support;

[0025] The dynamometer support is fixedly arranged, the hydraulic cylinder is fixedly installed on the dynamometer support, and the end of the piston rod of the hydraulic cylinder is arranged downward;

[0026] The electromagnet is installed on the dynamometer support through the force application support. The electromagnet is located directly below the end of the piston rod of the hydraulic cylinder, and the pressure block is arranged at the lower end of the electromagnet;

[0027] At least one load cell of the target weighing bar is located directly below the pressing block. The control ends of the hydraulic cylinder and the electromagnet are both connected to the controller. The controller attracts / releases the pressing block through the electromagnet, and transmits the pressure of the hydraulic cylinder to the target weighing bar through the pressing block.

[0028] In the above-mentioned weighing bar automatic compensation device, as a preferred solution, the hydraulic dynamometer further includes a measuring load cell;

[0029] The measuring load cell is arranged at the end of the piston rod of the hydraulic cylinder. The output end of the measuring load cell is electrically connected to the controller, and the measuring load cell is used to obtain the pressure of the hydraulic cylinder.

[0030] In the above-mentioned weighing bar automatic compensation device, as a preferred solution, the automatic compensation device further includes a camera. The camera is fixed to the dynamometer bracket. The camera is used to obtain the video information of the target weighing bar during the test, and the video information is used to automatically identify the weighing bar identity number through the video.

[0031] This application also provides a weighing bar automatic compensation method for adjusting and compensating the weighing accuracy of a target weighing bar. The target weighing bar includes at least one load cell arranged in parallel. The automatic compensation method includes:

[0032] Sequentially apply a preset pressure value to each load cell on the target weighing bar separately, and obtain the corresponding output value when each load cell is applied with the preset pressure value;

[0033] Calculate the adjacent influence factor of each load cell; the definition of the adjacent influence factor is one or two influence factors of one or two adjacent load cells when a load cell is applied with a preset pressure value;

[0034] Obtain the influence factor relationship network according to the adjacent influence factor of each load cell;

[0035] Calculate the compensation resistance value of each load cell based on the influence factor relationship network.

[0036] In the above-mentioned weighing bar automatic compensation method, as a preferred solution, the sequentially applying a preset pressure value to each load cell on the target weighing bar separately includes:

[0037] Apply a preset pressure value to the first load cell on the target weighing bar separately, and obtain the first output value of the target weighing bar;

[0038] Perform a preset displacement on the target weighing bar, apply a preset pressure value separately to the second weighing sensor on the target weighing bar, and obtain the second output value of the target weighing bar;

[0039] ……

[0040] Perform a preset displacement on the target weighing bar, apply a preset pressure value separately to the nth weighing sensor on the target weighing bar, and obtain the nth output value of the target weighing bar;

[0041] Calculate the adjacent influence factor of each weighing sensor through the following formula:

[0042] Δ1 = ε + ε * β12;

[0043] Δ2 = ε + ε * β21 + ε * β23;

[0044] ………

[0045] Δn - 1 = ε + ε * β(n - 1)(n - 2) + ε * β(n - 1)n;

[0046] Δn = ε + ε * βn(n - 1);

[0047] Among them, the target weighing bar includes n weighing sensors arranged in parallel, ε is the preset pressure value, β12 is the influence factor of the second weighing sensor when the first weighing sensor is stressed, and βn(n - 1) is the influence factor of the (n - 1)th weighing sensor when the nth weighing sensor is stressed;

[0048] Where:

[0049] For the kth weighing sensor, it has two adjacent influence factors, namely βk(k - 1) and βk(k + 1); Δk represents the output value of the target weighing bar when the kth weighing sensor is stressed.

[0050] According to the weighing bar automatic compensation device and method of the above embodiment, by controlling the traction mechanism through the controller, the target weighing bar can be displaced presetly, enabling a single weighing sensor to correspond to the force application unit of the hydraulic dynamometer in sequence, realizing the individual detection and compensation of each weighing sensor, effectively avoiding the adverse effects of mutual interference between adjacent weighing sensors on the adjustment and compensation, greatly improving the accuracy of the adjustment and compensation, thereby ensuring the overall metrological performance and accuracy of the weighing bar; aiming at the problems of large weight and difficult operation of the weighing bar, the traction mechanism can automatically traction and move the target weighing bar without manual laborious handling, greatly reducing the labor intensity; at the same time, the controller controls the automatic operation of the whole process, realizing automatic calculation and automatic comparison. Compared with manual calculation, not only the efficiency is greatly improved, but also the accuracy is higher and the consistency is better. Brief Description of the Drawings

[0051] Figure 1 This is a top view structural schematic diagram of the automatic compensation device adapted to the weighing rod provided by the embodiment of the present application;

[0052] Figure 2 This is a structural schematic diagram of the force application unit of the automatic compensation device adapted to the weighing rod provided by the embodiment of the present application;

[0053] Figure 3 This is a system structure diagram of the automatic compensation device adapted to the weighing rod provided by the embodiment of the present application;

[0054] Figure 4 This is a schematic diagram of the first test state of the weighing rod in the automatic compensation method of the weighing rod provided by the embodiment of the present application;

[0055] Figure 5 This is a schematic diagram of the second test state of the weighing rod in the automatic compensation method of the weighing rod provided by the embodiment of the present application.

[0056] Reference numerals in the figure: 1, PLC controller; 2, servo motor; 3, shaft connector; 4, position weighing sensor; 5, ball screw; 6, hydraulic dynamometer table; 7, traction bracket; 8, rotating nut; 9, second slider; 10, position weighing sensor; 11, left bearing block; 12, resistance automatic compensator; 13, right bearing block; 14, first balance guide rail; 15, second balance guide rail; 16, target weighing rod; 17, third slider; 18, third connecting plate; 19, first slider; 20, first connecting plate; 21, computer; 22, pressing block; 23, electromagnet; 24, force application bracket; 25, hydraulic cylinder; 26, dynamometer bracket; 27, measuring weighing sensor; 28, camera. Detailed implementation manners

[0057] The present application will be further described in detail below in conjunction with the accompanying drawings through specific implementation manners. Similar elements in different implementation manners are labeled with related similar element numbers. In the following implementation manners, many details are described to enable a better understanding of the present application. However, those skilled in the art can easily recognize that some of these features can be omitted in different situations, or can be replaced by other elements, materials, or methods. In some cases, some operations related to the present application are not shown or described in the specification, which is to avoid the core part of the present application being overwhelmed by excessive description. For those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0058] In addition, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can also be reordered or adjusted in a manner obvious to those skilled in the art. Therefore, the various sequences in the specification and drawings are only for clearly describing a certain embodiment and do not mean a necessary sequence, unless it is stated otherwise that a certain sequence must be followed.

[0059] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any sequential or technical meaning. And the "connection" and "coupling" mentioned in this application, unless otherwise specified, both include direct and indirect connection and coupling.

[0060] Please refer to Figure 1 and Figure 2 , to solve the technical problem that in the existing weighing rod, since adjacent weighing sensors will affect each other and the weighing rod is relatively heavy, it is difficult to operate when adjusting and compensating each weighing sensor of the weighing rod. In the embodiments of the present application, an automatic compensation device adapted to the weighing rod is provided, which is used to adjust and compensate the weighing accuracy of the target weighing rod. The target weighing rod includes at least one weighing sensor arranged in parallel. The automatic compensation device includes:

[0061] A traction mechanism, on which the target weighing rod is arranged, and the traction mechanism is used to traction the target weighing rod so that the target weighing rod undergoes a preset displacement;

[0062] A hydraulic force measuring machine, on which a force applying unit is arranged, and the hydraulic force measuring machine is used to apply a preset pressure value to at least one weighing sensor of the target weighing rod through the force applying unit;

[0063] A controller, which is respectively connected to and controls the traction mechanism, the hydraulic force measuring machine, and the force applying unit;

[0064] The controller controls the traction mechanism to make the target weighing rod undergo at least one preset displacement, so that a single weighing sensor on the target weighing rod corresponds to the force applying unit of the hydraulic force measuring machine;

[0065] When there is a weighing sensor on the target weighing rod corresponding to the force applying unit of the hydraulic force measuring machine, the controller controls the hydraulic force measuring machine to apply a preset pressure value to the current weighing sensor on the target weighing rod corresponding to the force applying unit through the force applying unit.

[0066] In the above-described automatic compensation device adapted to a weighing rod, as a preferred solution, the automatic compensation device further includes a processor and a resistor automatic compensator; the resistor automatic compensator is connected to the target weighing rod for obtaining the actual weighing result of the resistor automatic compensator; the processor is connected to the controller for setting a preset displacement and / or a preset pressure value through the controller; the processor is also connected to the target weighing rod through the resistor automatic compensator, and the processor calculates and obtains a compensation resistance value based on the actual weighing result and the preset pressure value.

[0067] Please refer to Figure 3 , in some embodiments, the controller is a PLC controller.

[0068] Please refer to Figure 3 , in some embodiments, the processor is a computer.

[0069] In the above-described automatic compensation device adapted to a weighing rod, as a preferred solution, the traction mechanism includes a power source, a ball screw, a rotating nut, a balance guide rail, a first slider, and a first connecting plate; the control end of the power source is connected to the controller, the output end of the power source is connected to the ball screw, the rotating nut is threadedly connected to the ball screw, the balance guide rail is fixedly arranged in parallel with the ball screw, one end of the first slider is slidably connected to the balance guide rail, the other end is fixedly connected to the rotating nut, the first connecting plate is fixedly arranged on the first slider, and the target weighing rod is installed on the first connecting plate.

[0070] In the above-described automatic compensation device adapted to a weighing rod, as a preferred solution, the power source includes a servo motor and a shaft connector, the servo motor is connected to the ball screw through the shaft connector, and the control end of the servo motor is connected to the controller; left and right bearing seats are respectively arranged at both ends of the ball screw.

[0071] In the above-described automatic compensation device adapted to a weighing rod, as a preferred solution, there are two balance guide rails, which are symmetrically arranged on both sides of the ball screw respectively; the traction mechanism further includes a second slider, a third slider, and a third connecting plate; the second slider is fixedly connected to the rotating nut, the second slider is symmetrically arranged with the first slider and is slidably connected to the balance guide rail on the opposite side of the first slider; the third slider is arranged on the same side of the first slider, the third slider is slidably connected to the balance guide rail, the third connecting plate is fixedly connected to the third slider, and the target weighing rod is installed on the first connecting plate and the third connecting plate.

[0072] In the above-described automatic compensation device adapted to a weighing rod, as a preferred solution, the hydraulic force measuring machine includes a force measuring machine bracket and a hydraulic cylinder. The force applying unit includes a pressure block, an electromagnet, and a force applying bracket. The force measuring machine bracket is fixedly arranged, the hydraulic cylinder is fixedly installed on the force measuring machine bracket, and the end of the piston rod of the hydraulic cylinder is arranged downward. The electromagnet is installed on the force measuring machine bracket through the force applying bracket, the electromagnet is located directly below the end of the piston rod of the hydraulic cylinder, and the pressure block is arranged at the lower end of the electromagnet. At least one weighing sensor of the target weighing rod is located directly below the pressure block. The control ends of the hydraulic cylinder and the electromagnet are both connected to the controller. The controller attracts / releases the pressure block through the electromagnet, and transmits the pressure of the hydraulic cylinder to the target weighing rod through the pressure block.

[0073] In the above-described automatic compensation device adapted to a weighing rod, as a preferred solution, the hydraulic force measuring machine further includes a measuring weighing sensor. The measuring weighing sensor is arranged at the end of the piston rod of the hydraulic cylinder. The output end of the measuring weighing sensor is electrically connected to the controller, and the measuring weighing sensor is used to obtain the pressure of the hydraulic cylinder.

[0074] In the above-described automatic compensation device adapted to a weighing rod, as a preferred solution, the automatic compensation device further includes a camera. The camera is fixed to the force measuring machine bracket. The camera is used to obtain video information of the target weighing rod during testing, and the video information is used to automatically identify the weighing rod identity number through the video.

[0075] Please refer to Figure 3 , the working process of the automatic compensation device in some embodiments is as follows:

[0076] Manually place the weighing rod on the traction mechanism; activate the automatic compensation button related to the computer; the computer sends relevant signals to the PLC controller, and the PLC controller drives the servo motor; the servo motor drives the ball screw to move; the ball screw drives the traction mechanism to act; after the weighing rod reaches the relevant position, the position weighing sensor feeds back to the PLC controller; the PLC controller controls the electromagnetic mechanism to release the pressure block; then the PLC controller starts the hydraulic force measuring machine and applies a certain pressure to the weighing rod through the pressure block; the computer automatically calculates the resistance value to be compensated through the resistance automatic compensator; after completion, the electromagnetic mechanism sucks the pressure block; the servo motor continues to control the ball screw, the traction mechanism, and the weighing rod to move forward or backward. In this way, through multiple automatic actions such as traction, movement, release, pressure application, calculation of the compensation resistance value, and suction, the computer automatically calculates the resistance value to be compensated for each weighing sensor, and finally conducts automatic comparison and verification one by one to complete the automatic compensation of the weighing rod.

[0077] In some embodiments, the right bearing block 13, the left bearing block 11, the first balance guide rail 14, the second balance guide rail 15, the position load cell 4, and the position load cell 10 are fixed to the hydraulic dynamometer tabletop 6 by bolts; the PLC controller 1, the resistance automatic compensator 12, and the computer 21 are placed on the hydraulic dynamometer tabletop 6; the ball screw 5 is fixed to the right bearing block 13 and the left bearing block 11; a rotating nut 8 is arranged on the ball screw 5; the servo motor 2 is connected to the ball screw 5 as a whole through the shaft connector 3.

[0078] The rotating nut 8, the second slider 9, and the first slider 19 are connected as a whole by bolts and the first connecting plate 20, and a position load cell detection plate is arranged on the first connecting plate 20.

[0079] The third connecting plate 18 and the third slider 17 are connected as a whole by bolts.

[0080] The traction bracket 7 is connected as a whole to the third connecting plate 18 and the first connecting plate 20 by bolts.

[0081] The pitch of the ball screw 5 is L. When the servo motor 2 rotates n turns, the rotating nut 8 will move a distance of L * n, and the target weighing rod 16 is driven by the traction bracket 7 to move back and forth. The specific distance is realized by the computer 21 transmitting to the PLC controller 1, and the PLC controller 1 driving the servo motor 2.

[0082] The hydraulic cylinder 25 and the measuring load cell 27 are fixed to the dynamometer bracket 26 by bolts; the camera 28 is fixed to the dynamometer bracket 26 by a bracket to automatically identify the production number of the weighing rod through video; the electromagnet 23 is fixed to the dynamometer bracket 26 by the force application bracket 24, and the pressure block 22 is attracted / released by the electromagnet 23. The pressure of the hydraulic cylinder 25 is transmitted to the target weighing rod 16 through the pressure block 22. The specific action is realized by the computer 21 transmitting to the PLC controller 1, and the PLC controller 1 driving the electromagnet 23.

[0083] The present application also provides an automatic compensation method suitable for weighing rods, which is used to adjust and compensate the weighing accuracy of the target weighing rod. The target weighing rod includes at least one weighing sensor arranged in parallel. The automatic compensation method includes:

[0084] Sequentially applying a preset pressure value to each weighing sensor on the target weighing rod alone, and obtaining the output value corresponding to each weighing sensor when the preset pressure value is applied;

[0085] Calculating the adjacent influence factor of each weighing sensor; the adjacent influence factor is defined as one or two influence factors of one or two adjacent weighing sensors when a weighing sensor is applied with a preset pressure value;

[0086] Obtain an influence factor relationship network according to the adjacent position influence factor of each load cell.

[0087] Calculate the compensation resistance value of each load cell based on the influence factor relationship network.

[0088] In the above method for automatic compensation of the weighing rod, as a preferred solution, the step of separately applying a preset pressure value to each load cell on the target weighing rod in sequence includes:

[0089] Separate apply a preset pressure value to the first load cell on the target weighing rod, and obtain the first output value of the target weighing rod.

[0090] Displace the target weighing rod by a preset displacement, separately apply a preset pressure value to the second load cell on the target weighing rod, and obtain the second output value of the target weighing rod.

[0091] ……

[0092] Displace the target weighing rod by a preset displacement, separately apply a preset pressure value to the nth load cell on the target weighing rod, and obtain the nth output value of the target weighing rod.

[0093] Calculate the adjacent position influence factor of each load cell through the following formula:

[0094] Δ1 = ε + ε * β12;

[0095] Δ2 = ε + ε * β21 + ε * β23;

[0096] ………

[0097] Δn - 1 = ε + ε * β(n - 1)(n - 2) + ε * β(n - 1)n;

[0098] Δn = ε + ε * βn(n - 1);

[0099] Wherein, the target weighing rod includes n load cells arranged in parallel, ε is the preset pressure value, β12 is the influence factor of the second load cell when the first load cell is stressed, and βn(n - 1) is the influence factor of the (n - 1)th load cell when the nth load cell is stressed;

[0100] Wherein:

[0101] For the kth load cell, it has two adjacent position influence factors, namely βk(k - 1) and βk(k + 1); Δk represents the output value of the target weighing rod when the kth load cell is stressed.

[0102] In some embodiments, the target consists of multiple load cells, which are interrelated and interfere with each other. According to the physical characteristics of the load cells, there are n load sensing points from end to end on the same sensor, and each sensing point is denoted as α1, ……, αn respectively. In order to conduct a pressure test on each load sensing point, it is necessary to design the length L2 of the pressure block (22) to be the same as the length of a single load cell (L1). When a standard pressure is applied to each sensing point respectively, due to the rigidity constraint of the load cell, the pressure at this sensing point will have a relatively obvious impact on the output of the adjacent sensing point, but the impact on the alternate sensing point can be ignored. Denote the influence factor of the first sensing point on the second sensing point as β12. At this time, when the standard pressure ε is applied to the first sensing point, there will be a pressure component of ε*β12 reflected at the second sensing point. At this time, the total output value of the entire load cell is ε + ε*β12. Figure 4 (Shown in the weighing rod test state 1).

[0103] Similarly, when the standard pressure ε is applied to the fourth sensing point, there will be pressure components of ε*β43 and ε*β45 reflected at the third and fifth sensing points respectively. At this time, the total output value of the entire load cell is ε + ε*β43 + ε*β45. Figure 5 (Shown in the weighing rod test state 2).

[0104] There are a total of 2n - 2 influence factors in the entire load cell system, namely β12, β21, β23 ……, β(n - 1)(n - 2), β(n - 1)n, βn(n - 1). Among them, the influence factors between different sensing points should be approximately similar in value and opposite in sign. When the system calculates the automatic compensation parameters, first apply the same standard pressure ε to each point in turn from both sides to the center, and measure the total output value of the load cell respectively. (Δx represents the overall output value after applying the standard pressure to the nth sensing point).

[0105] Then repeat the previous operation from the center to both sides, and record the relevant total output values again. According to the principle that the total output values of each point under the two sets of cycles should be basically the same, a relationship network of influence factors is formed. In this network, adjacent influence factors do not have absolute values, but only have a certain corresponding relationship. At this time, the system will select and match in combination with the resistance values of the common precision resistor E192 series, and give 3 - 4 groups of recommended compensation resistor values and their respective theoretical confidence levels. Then the system will automatically switch each group of compensation resistors to be connected to the sensor on the resistance compensation tooling, apply the standard pressure to each point again, measure the consistency and error value of the overall system output, and finally record the compensation resistor value that meets the error requirements in the archive and mark the accuracy level, thus completing the automatic measurement and calculation requirements of the compensation parameters of this sensor.

[0106] The operator welds the corresponding compensation resistor into the corresponding position of the sensor. The system will apply the standard pressure at each point again and test the output value of the sensor to verify whether the operation is correct. During the whole process, most of the operations and calculations are automatically carried out by the system software, avoiding uncertain factors such as operation errors and calculation errors that may be caused by manual operation. At the same time, a parameter database of all sensor parameters can be formed, which is convenient for finding specific laws in the later stage to reduce operations and improve production efficiency.

[0107] Those skilled in the art can understand that all or part of the functions of the various methods in the above embodiments can be implemented in a hardware manner or in a computer program manner. When all or part of the functions in the above embodiments are implemented in a computer program manner, the program can be stored in a computer-readable storage medium. The storage medium may include: read-only memory, random access memory, magnetic disk, optical disk, hard disk, etc. The above functions are realized by a computer executing the program. For example, the program is stored in the memory of the device, and when the processor executes the program in the memory, the above-mentioned all or part of the functions can be realized. In addition, when all or part of the functions in the above embodiments are implemented in a computer program manner, the program can also be stored in a storage medium such as a server, another computer, magnetic disk, optical disk, flash drive or mobile hard disk, and saved to the memory of the local device by downloading or copying, or the system of the local device is updated in version. When the processor executes the program in the memory, the above-mentioned all or part of the functions in the embodiments can be realized.

[0108] The above uses specific examples to elaborate on the present application, which is only used to help understand the present application and is not intended to limit the present application. For those skilled in the art of the present application, according to the idea of the present application, several simple deductions, deformations or substitutions can also be made.

Claims

1. An automatic compensation device adapted to a weighing bar, which is used to adjust and compensate the weighing accuracy of a target weighing bar. The target weighing bar includes at least one weighing sensor arranged side by side. It is characterized in that, The automatic compensation device includes: A traction mechanism, on which the target weighing rod is arranged, and the traction mechanism is used to traction the target weighing rod to make the target weighing rod perform a preset displacement; A hydraulic dynamometer, on which a force application unit is arranged, and the hydraulic dynamometer is used to apply a preset pressure value to at least one weighing sensor of the target weighing rod through the force application unit; A controller, which is respectively connected to and controls the traction mechanism, the hydraulic dynamometer and the force application unit; The controller controls the traction mechanism to make the target weighing rod perform at least one preset displacement, so that a single weighing sensor on the target weighing rod corresponds to the force application unit of the hydraulic dynamometer; When there is a weighing sensor on the target weighing rod corresponding to the force application unit of the hydraulic dynamometer, the controller controls the hydraulic dynamometer to apply a preset pressure value to the weighing sensor on the target weighing rod currently corresponding to the force application unit through the force application unit.

2. The automatic compensation device adapted to the weighing rod according to claim 1, characterized in that, The automatic compensation device further includes a processor and a resistance automatic compensator; The resistance automatic compensator is connected to the target weighing rod and is used to obtain the actual weighing result of the resistance automatic compensator; The processor is connected to the controller and is used to set a preset displacement and / or a preset pressure value through the controller; The processor is also connected to the target weighing rod through the resistance automatic compensator, and the processor calculates and obtains a compensation resistance value according to the actual weighing result and the preset pressure value.

3. The automatic compensation device adapted to the weighing rod according to claim 1, characterized in that, The traction mechanism includes a power source, a ball screw, a rotating nut, a balance guide rail, a first slider and a first connecting plate; The control end of the power source is connected to the controller, the output end of the power source is connected to the ball screw, the rotating nut is threadedly connected to the ball screw, the balance guide rail is fixedly arranged parallel to the ball screw, one end of the first slider is slidably connected to the balance guide rail, the other end is fixedly connected to the rotating nut, the first connecting plate is fixedly arranged on the first slider, and the target weighing rod is installed on the first connecting plate.

4. The automatic compensation device adapted to a weighing bar according to claim 3, characterized in that, The power source includes a servo motor and a shaft connector, the servo motor is connected to the ball screw through the shaft connector, and the control end of the servo motor is connected to the controller; Both ends of the ball screw are respectively provided with a left bearing seat and a right bearing seat.

5. The automatic compensation device adapted to a weighing bar according to claim 3, characterized in that, There are two balance guide rails, which are symmetrically arranged on both sides of the ball screw respectively; The traction mechanism further includes a second slider, a third slider and a third connecting plate; The second slider is fixedly connected to the rotating nut, the second slider is symmetrically arranged with the first slider and is slidably connected to the balance guide rail on the opposite side of the first slider; The third slider is arranged on the same side of the first slider, the third slider is slidably connected to the balance guide rail, the third connecting plate is fixedly connected to the third slider, and the target weighing rod is installed on the first connecting plate and the third connecting plate.

6. The automatic compensation device adapted to a weighing bar according to claim 1, characterized in that, The hydraulic dynamometer includes a dynamometer support and a hydraulic cylinder, and the force application unit includes a pressure block, an electromagnet and a force application support; The force measuring machine bracket is fixedly arranged, the hydraulic cylinder is fixedly installed on the force measuring machine bracket, and the end of the piston rod of the hydraulic cylinder is arranged downward; The electromagnet is installed on the force measuring machine bracket through the force applying bracket, the electromagnet is located directly below the end of the piston rod of the hydraulic cylinder, and the pressing block is arranged at the lower end of the electromagnet; At least one weighing sensor of the target weighing rod is located directly below the pressing block, and the control ends of the hydraulic cylinder and the electromagnet are both connected to the controller. The controller sucks / releases the pressing block through the electromagnet, and transmits the pressure of the hydraulic cylinder to the target weighing rod through the pressing block.

7. The automatic compensation device adapted to the weighing rod according to claim 6, characterized in that, The hydraulic force measuring machine further includes a measuring weighing sensor; The measuring weighing sensor is arranged at the end of the piston rod of the hydraulic cylinder, and the output end of the measuring weighing sensor is electrically connected to the controller. The measuring weighing sensor is used to obtain the pressure of the hydraulic cylinder.

8. The automatic compensation device for a weighing bar according to claim 6, characterized in that, The automatic compensation device further includes a camera. The camera is fixed to the force measuring machine bracket. The camera is used to obtain video information of the target weighing rod during testing, and the video information is used to automatically identify the weighing rod identity number through the video.

9. An automatic compensation method adapted to a weighing bar is used to perform an adjustment compensation test on the weighing accuracy of a target weighing bar. The target weighing bar includes at least one weighing sensor arranged side by side. It is characterized in that, The automatic compensation method includes: Sequentially applying a preset pressure value to each weighing sensor on the target weighing rod separately, and obtaining the corresponding output value when each weighing sensor is applied with the preset pressure value; Calculating the adjacent influence factor of each weighing sensor; the definition of the adjacent influence factor is one or two influence factors of one or two adjacent weighing sensors when a weighing sensor is applied with a preset pressure value; Obtaining an influence factor relationship network according to the adjacent influence factor of each weighing sensor; Calculating the compensation resistance value of each weighing sensor based on the influence factor relationship network.

10. The automatic method adapted to a weighing bar according to claim 9, characterized in that, The sequentially applying a preset pressure value to each weighing sensor on the target weighing rod separately includes: Applying a preset pressure value to the first weighing sensor on the target weighing rod separately, and obtaining the first output value of the target weighing rod; Performing a preset displacement on the target weighing rod, applying a preset pressure value to the second weighing sensor on the target weighing rod separately, and obtaining the second output value of the target weighing rod; …… Performing a preset displacement on the target weighing rod, applying a preset pressure value to the nth weighing sensor on the target weighing rod separately, and obtaining the nth output value of the target weighing rod; Calculating the adjacent influence factor of each weighing sensor through the following formula: Δ1 = ε + ε * β12; Δ2 = ε + ε * β21 + ε * β23; ……… Δn - 1 = ε + ε * β(n - 1)(n - 2) + ε * β(n - 1)n; Δn = ε + ε * βn(n - 1); Wherein, the target weighing rod includes n weighing sensors arranged in parallel, ε is the preset pressure value, β12 is the influence factor of the second weighing sensor when the first weighing sensor is stressed, and βn(n - 1) is the influence factor of the (n - 1)th weighing sensor when the nth weighing sensor is stressed; Wherein: For the k-th load cell, it has two adjacent influence factors, namely βk(k - 1) and βk(k + 1); Δk represents the output value of the target weighing rod when the k-th load cell is stressed.

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