A position changing device for multi-station welding

Abstract

The present invention relates to the technical field of multi-station welding, and in particular to a displacement device for multi-station welding. Based on the obtained temperature time series of each historical welded part, the degree of temperature variation regularity of each temperature subsequence to be analyzed is determined; according to the degree of temperature variation regularity, the difference between each welding temperature of the same type and the welding temperature at the next moment, and the number of welding temperature types corresponding to each historical welded part, the temperature increase value of each type of welding temperature at the future moment is determined, and then the temperature increase value of the welding temperature of the current welded part at the future moment is determined to obtain the welding temperature of the current welded part at the future moment; if the welding temperature at the future moment is greater than or equal to the critical temperature, the spraying amount of the coolant of the current welded part is determined. The present invention realizes the cooling process of adaptively spraying the coolant by determining the welding temperature at the future moment, which can effectively avoid thermal deformation of the welded part and ultimately improve the welding quality.

Description

Technical Field

[0001] The invention relates to the technical field of multi-station welding, and in particular to a position shifting device for multi-station welding. Background Art

[0002] In the field of industrial manufacturing, multi-station welding positioners have become key equipment for improving welding efficiency and quality. They are mostly suitable for large-scale production and welding of complex structural parts, such as automobiles, ships, railways, heavy machinery and other industries. The existing multi-station welding positioner controls the servo motor to perform omnidirectional position shifting, that is, each working area of ​​the positioner has multiple servo motors working together to flip and shift the welding workpiece at various angles, which greatly avoids working blind spots and dead angles, so as to facilitate production and improve quality.

[0003] During the welding process, high-temperature welding of the workpiece may cause thermal deformation, which will affect the welding quality. Specifically, although the displacement device can adjust the position of the workpiece at multiple angles to reduce errors, if the thermal deformation is not effectively controlled, the welding position may shift, which will affect the docking accuracy and overall quality of the welded joint, resulting in insufficient structural strength or defects. Therefore, effective control of thermal deformation is one of the keys to ensuring welding quality. Summary of the invention

[0004] In order to solve the technical problem that the welding quality of the above-mentioned existing welding positioner is poor due to the influence of high-temperature welding thermal deformation, the object of the present invention is to provide a multi-station welding positioner, and the technical solution adopted is as follows:

[0005] An embodiment of the present invention provides a multi-station welding position changing device, comprising a processor and a memory, wherein the processor is used to process instructions stored in the memory to implement the following process:

[0006] Acquire a temperature time series of several historical welded parts and a welding temperature of a current welded part; wherein the temperature time series is composed of a plurality of welding temperatures arranged in chronological order and located before a first critical temperature;

[0007] According to each temperature subsequence to be analyzed corresponding to each type of welding temperature in the temperature time series of each historical welded part, the degree of temperature variation regularity of each temperature subsequence to be analyzed is determined; wherein welding temperatures with the same temperature value are determined as welding temperatures of the same type;

[0008] Determine the temperature increase value of each type of welding temperature at a future moment according to the degree of the temperature variation regularity, the difference between each welding temperature of the same type and the welding temperature at a later moment, and the number of welding temperature types corresponding to each historical welded part;

[0009] Determine the temperature increase value of the welding temperature of the current welding part at the future time, and obtain the welding temperature of the current welding part at the future time according to the welding temperature of the current welding part and the temperature increase value at the future time;

[0010] If the welding temperature at the future moment is greater than or equal to the critical temperature, the spraying amount of the coolant of the current welded part is determined according to the welding temperature of the current welded part at the future moment.

[0011] Further, the step of determining the degree of temperature variation regularity of each temperature subsequence to be analyzed according to each temperature subsequence to be analyzed corresponding to each type of welding temperature in each historical welding part temperature time series includes:

[0012] In the temperature time series, a subsequence consisting of any welding temperature of any type and a number of welding temperatures located before the welding temperature of the type is used as a temperature subsequence to be analyzed for the welding temperature of the type;

[0013] Determine the degree of temperature change regularity of each temperature subsequence to be analyzed according to the distribution of temperature change values ​​in each temperature subsequence to be analyzed corresponding to each type of welding temperature;

[0014] The temperature change value is equal to the difference between two adjacent welding temperatures in the temperature subsequence to be analyzed.

[0015] Further, the temperature variation regularity of each temperature subsequence to be analyzed is determined according to the distribution of temperature variation values ​​in each temperature subsequence to be analyzed corresponding to each type of welding temperature, including:

[0016] In each temperature subsequence to be analyzed, the absolute value of the difference between two adjacent temperature change values ​​is calculated as the temperature change difference value;

[0017] Determine the cumulative value of all temperature change difference values ​​in the same temperature subsequence to be analyzed, and then normalize the cumulative value to obtain a normalized value;

[0018] The normalized values ​​are subjected to negative correlation processing to determine the degree of temperature variation regularity of each temperature subsequence to be analyzed.

[0019] Further, the determining of the temperature increase value of each type of welding temperature at a future moment according to the degree of the temperature variation regularity, the difference between each welding temperature of the same type and the welding temperature at a later moment, and the number of welding temperature types corresponding to each historical welded part, includes:

[0020] According to the degree of temperature variation regularity of each temperature subsequence to be analyzed corresponding to each type of welding temperature and the difference between each welding temperature of the same type and the welding temperature at the next moment, determine the temperature variation index of each type of welding temperature of each historical welded part at the future moment;

[0021] According to the temperature change index of each type of welding temperature of each historical welded part at the future moment and the number of welding temperature types corresponding to each historical welded part, the temperature increase value of each type of welding temperature at the future moment is determined.

[0022] Further, the temperature variation index of each type of welding temperature of each historical welded part at a future moment is determined according to the degree of temperature variation regularity of each temperature subsequence to be analyzed corresponding to each type of welding temperature and the difference between each welding temperature of the same type and the welding temperature at a later moment, including:

[0023] For any historical welded part, determine the proportion of the temperature variation regularity degree of each to-be-analyzed temperature subsequence of a single type of welding temperature in the accumulated value of the temperature variation regularity degree, wherein the accumulated value of the temperature variation regularity degree is equal to the accumulated value of the temperature variation regularity degree of all to-be-analyzed temperature subsequences corresponding to the single type of welding temperature;

[0024] The proportion is used as the temperature change weight of the corresponding temperature subsequence to be analyzed, and the difference between each welding temperature of the same type and the welding temperature at the next moment is used as the temperature change factor of the corresponding welding temperature of the same type;

[0025] According to the temperature change weights of each temperature subsequence to be analyzed corresponding to each type of welding temperature and the temperature change factors of each type of welding temperature, the temperature change index of each type of welding temperature of each historical weldment at a future moment is determined.

[0026] Further, the method of determining the temperature change index of each type of welding temperature of each historical welded part at a future moment according to the temperature change weight of each temperature subsequence to be analyzed corresponding to each type of welding temperature and the temperature change factor of each type of welding temperature includes:

[0027] Calculate the product of the temperature change weight of the to-be-analyzed temperature subsequence of each welding temperature of the same type and the temperature change factor of the corresponding welding temperature;

[0028] The accumulated value of the products of all welding temperatures of the same type is used as a temperature change indicator of the corresponding type of welding temperature at a future moment.

[0029] Further, the step of determining the temperature increase value of each type of welding temperature at a future moment according to the temperature change index of each type of welding temperature of each historical welding part at a future moment and the number of welding temperature types corresponding to each historical welding part comprises:

[0030] The number of welding temperature types of each historical welded part is normalized to obtain the analysis basis index of each historical welded part; the ratio of the analysis basis index of a single historical welded part to the cumulative value of the analysis basis index of all historical welded parts is used as the welding temperature confidence index of the corresponding historical welded part;

[0031] According to the welding temperature confidence index of each historical welded part and the temperature variation index, the temperature increase value of each type of welding temperature at a future moment is determined.

[0032] Further, the determining of the temperature increase value of each type of welding temperature at a future moment according to the welding temperature confidence index and the temperature change index of each historical welding part includes:

[0033] For any type of welding temperature, determine a historical welded part with the type of welding temperature as a target historical welded part;

[0034] Calculate the product of the welding temperature confidence index of each target historical weldment and the temperature change index of the welding temperature of the corresponding target historical weldment at the future moment, and use the accumulated value of the products of all target historical weldments as the temperature increase value of the welding temperature of the type at the future moment.

[0035] Further, the step of determining the spraying amount of the coolant of the current weldment according to the welding temperature of the current weldment at a future moment includes:

[0036] Calculate the difference between the welding temperature of the current welded part and the critical temperature at the future moment, normalize the difference between the two temperatures, and obtain the spraying amount control coefficient;

[0037] The product of the spraying amount control coefficient and the preset spraying amount adjustment reference value is used as the spraying amount adjustment value of the current weldment; wherein the preset spraying amount adjustment reference value is equal to the difference between the maximum coolant spraying amount and the minimum coolant spraying amount;

[0038] The value obtained by adding the spraying amount adjustment value of the current welded part to the minimum coolant spraying amount is used as the spraying amount of the coolant of the current welded part.

[0039] A multi-station welding position shifting device, comprising a position shifting mechanism for welding, the multi-station welding position shifting device also comprising a coolant spraying monitoring device, the coolant spraying monitoring device comprising an infrared temperature sensor and a controller;

[0040] The infrared temperature sensor signal is connected to the controller, and the infrared temperature sensor is used to obtain a temperature time series of several historical welded parts and a welding temperature of a current welded part; wherein the temperature time series is composed of a plurality of welding temperatures arranged in chronological order and located before a first critical temperature;

[0041] The controller determines the degree of temperature variation regularity of each temperature subsequence to be analyzed according to each temperature subsequence to be analyzed corresponding to each type of welding temperature in the received temperature time series of each historical welded part; wherein welding temperatures with the same temperature values ​​are determined as welding temperatures of the same type;

[0042] Determine the temperature increase value of each type of welding temperature at a future moment according to the degree of the temperature variation regularity, the difference between each welding temperature of the same type and the welding temperature at a later moment, and the number of welding temperature types corresponding to each historical welded part;

[0043] Determine the temperature increase value of the welding temperature of the current welding part at the future time, and obtain the welding temperature of the current welding part at the future time according to the welding temperature of the current welding part and the temperature increase value at the future time;

[0044] If the welding temperature at the future moment is greater than or equal to the critical temperature, the spraying amount of the coolant of the current welded part is determined according to the welding temperature of the current welded part at the future moment.

[0045] The present invention has the following beneficial effects:

[0046] The present invention provides a multi-station welding position shifting device, which determines the temperature rise value of each type of welding temperature at a future moment by analyzing the temperature change performance of the historical welded parts, and determines the welding temperature of the current welded parts at a future moment based on this, and then judges the comparative relationship between the welding temperature at a future moment and the critical temperature. When it is greater than or equal to the critical temperature, the spraying amount of the coolant of the current welded parts is determined according to the welding temperature of the current welded parts at a future moment. Compared with the existing manual judgment and adjustment of the coolant spraying situation, the present invention determines the spraying amount of the coolant by the welding temperature at a future moment, which can effectively avoid the thermal deformation caused by the high-temperature welding of the workpiece during the welding process, and at the same time reduce the situation of insufficient or wasteful use of coolant, and realize the intelligent rotation of the rotating main table to move the welding station to the cooling station, further improving the welding quality of the multi-station welding position shifting device when applied to welding. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0048] Figure 1 It is a structural schematic diagram of a position shifting mechanism used for welding in a position shifting device for multi-station welding of the present invention;

[0049] Figure 2 It is a flow chart of a data processing process in a position shifting device for multi-station welding according to the present invention;

[0050] Figure 3 Schematic diagram of the process of step S202 in an embodiment of the present invention;

[0051] Figure 4 Schematic diagram of the process of step S213 in an embodiment of the present invention;

[0052] Figure 5 Schematic diagram of the process of step S223 in an embodiment of the present invention;

[0053] The description of the accompanying drawings is as follows: 1 is a rotating work table, 2 is a longitudinal inclination adjustment device, 3 is an extending connecting rod, 4 is a positioner base, 5 is a dust cover, 6 is a partition support frame, 7 is a light-blocking isolation plate, 8 is a door frame reinforcement rib, 9 is a servo motor, 10 is a master control panel, 11 is a central control electrical cabinet, 12 is an electrical cabinet door, 13 is a height adjustment module, and 14 is a first rotating module. DETAILED DESCRIPTION

[0054] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the technical solutions proposed by the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0055] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0056] A multi-station welding position shifting device embodiment 1:

[0057] This embodiment provides a multi-station welding position changing device, including a position changing mechanism for welding. The structural schematic diagram of the position changing mechanism for welding is shown in FIG. Figure 1 As shown, in Figure 1 Among them, 1 is a rotating work table, 2 is a longitudinal inclination adjustment device, 3 is an extension connecting rod, 4 is a positioner base, 5 is a dust cover, 6 is a partition support frame, 7 is a light-blocking isolation plate, 8 is a door frame reinforcement rib, 9 is a servo motor, 10 is a master control panel, 11 is a central control electric cabinet, 12 is an electric cabinet door, 13 is a height adjustment module, and 14 is a first rotating module.

[0058] The position shifting device for multi-station welding also includes a coolant spray monitoring device, which includes an infrared temperature sensor and a controller. Among them, the infrared temperature sensor is usually installed on the current welding station, which can be used to monitor the actual welding temperature of the current welded part; the controller can be a built-in chip, which can be a computing control chip for data processing and machine control. The chip type is FPGA (Field-Programmable Gate Array). The built-in chip sends the data processing results to the control module of the rotating main table for subsequent processing. In addition, the infrared temperature sensor and the controller can also be integrated to form a device that integrates data acquisition and data processing functions.

[0059] The implementation process of the coolant spray monitoring device includes: determining the welding temperature of the current welded part at a future moment according to the distribution of welding temperature change values ​​of the historical welded parts and the current welded parts during the welding process, judging whether the welding area corresponding to the current welded part needs to be sprayed with coolant by the welding temperature at the future moment, and if necessary, sending the final coolant spraying amount to the control module of the rotating main table to spray the corresponding degree of coolant to avoid thermal deformation during the welding process and affect the final welding quality.

[0060] Specifically, this embodiment provides a data processing process in a multi-station welding position shifting device, such as Figure 2 As shown, the following steps are included:

[0061] S201, obtaining a temperature time series of several historical welded parts and a welding temperature of a current welded part.

[0062] In this embodiment, in order to prevent the temperature in the welding process from exceeding the critical temperature, the temperature time series of historical welds is obtained to quantify the temperature increase value of each type of welding temperature at a future moment; since the main purpose of this embodiment is to avoid thermal deformation of the current weld, when analyzing the temperature data of historical welds, it is necessary to analyze the relevant data that has not exceeded the critical temperature.

[0063] Specifically, first obtain the welding temperature of each historical weldment at each moment in the welding process to form a preliminary welding temperature sequence; determine the position where the welding temperature greater than or equal to the critical temperature appears for the first time in each preliminary welding temperature sequence, and record it as the target position; form a sequence of welding temperatures before the target position in each preliminary welding temperature sequence as the temperature time series of the corresponding historical weldment, and the temperature time series is composed of multiple welding temperatures arranged in chronological order and located before the first critical temperature; obtain the welding temperature of the current weldment, that is, obtain the welding temperature of the current weldment at the current moment, which is mainly used for subsequent prediction of the welding temperature at future moments.

[0064] It should be noted that the historical welded parts and the current welded parts belong to the same type of welded parts, and the critical temperature for deformation during the corresponding welding process is the same. The critical temperature is a parameter set during the production of the welded parts. In special cases, when the historical welded parts reach or exceed the critical temperature multiple times, the first time the critical temperature is reached is used as the boundary, and the welding temperature data before the boundary is extracted.

[0065] So far, this embodiment has obtained the temperature time series of each historical welded part and the welding temperature of the current welded part.

[0066] S202, determining the degree of temperature variation regularity of each temperature subsequence to be analyzed according to each temperature subsequence to be analyzed corresponding to each type of welding temperature in each historical welding part temperature time series.

[0067] In this embodiment, whether the temperature change of the welded parts during the welding process has a certain regularity refers to whether the welding heating rules are followed during the welding process. The welding heating rules can make the temperature change performance show a certain uniform change; at the same time, regularity also refers to the regularity of the temperature rise of the welded parts and the use of coolants during the welding process. The more regular the temperature change during the welding process, the higher the accuracy of quantifying the temperature rise value at the future moment. Therefore, the degree of regularity of temperature change can characterize the uniformity of the local welding temperature change, which is used for the subsequent calculation of the temperature rise value.

[0068] The above step S202 can be performed by Figure 3 The steps shown achieve:

[0069] S301 , in a temperature time series, taking a subsequence consisting of a plurality of welding temperatures preceding any welding temperature of each type as a temperature subsequence to be analyzed of a corresponding welding temperature of the corresponding type.

[0070] In this embodiment, welding temperatures with the same numerical value in the temperature time series may be located at different welding moments, and the temperature data change between the same welding temperature at different welding moments and the next adjacent moment can reflect the degree of temperature increase during the welding process, which is helpful for determining the temperature increase value at future moments. Therefore, in any temperature time series, welding temperatures with the same temperature numerical value are determined as welding temperatures of the same type, and each type has multiple corresponding welding temperatures. Based on the position of each welding temperature of each type in the temperature time series, each temperature subsequence to be analyzed corresponding to each type of welding temperature is obtained.

[0071] Specifically, in the temperature time series, any welding temperature of any type and a subsequence consisting of several welding temperatures before the welding temperature of the type are used as the temperature subsequence to be analyzed of the welding temperature of the type; for each welding temperature of each type, according to the same method of determining the temperature subsequence to be analyzed, each temperature subsequence to be analyzed corresponding to each type of welding temperature can be obtained.

[0072] Among them, the number of welding temperature data in a temperature subsequence to be analyzed can be set to 20, and the implementer can set it according to the data distribution of the specific actual temperature time series without specific limitation; the number of temperature subsequences to be analyzed corresponding to each type is consistent with the number of welding temperatures of the corresponding type.

[0073] S302, determining the degree of temperature variation regularity of each temperature subsequence to be analyzed according to the distribution of temperature variation values ​​in each temperature subsequence to be analyzed corresponding to each type of welding temperature.

[0074] In this embodiment, the temperature change value is equal to the difference between two adjacent welding temperatures in the temperature subsequence to be analyzed. The difference value can be the absolute value of the difference between the previous welding temperature and the next welding temperature, or the ratio of the two adjacent welding temperatures. The worse the stability of the temperature change value in the temperature subsequence to be analyzed, the worse the regularity of the temperature change of the subsequence. Therefore, the degree of temperature change regularity can be analyzed by the difference between two adjacent temperature change values ​​in the subsequence.

[0075] In the first step, in each temperature subsequence to be analyzed, the absolute value of the difference between two adjacent temperature change values ​​is calculated as the temperature change difference value.

[0076] The second step is to determine the cumulative value of all temperature change difference values ​​in the same temperature subsequence to be analyzed, and then normalize the cumulative value to obtain a normalized value.

[0077] The third step is to perform negative correlation processing on the normalized values ​​to determine the degree of temperature variation regularity of each temperature subsequence to be analyzed.

[0078] As an example, the calculation formula for the degree of temperature variation regularity of the mth temperature subsequence to be analyzed corresponding to the jth type of welding temperature of the ith historical weldment can be:

[0079] ; In the formula, represents the temperature variation regularity of the mth temperature subsequence to be analyzed corresponding to the welding temperature of the jth type of the i-th historical weldment, norm represents the linear normalization function, represents the number of welding temperature data in the mth temperature subsequence to be analyzed corresponding to the welding temperature of the jth type of the i-th historical weldment, represents the number of temperature change values ​​in the mth temperature subsequence to be analyzed corresponding to the welding temperature of the jth type of the i-th historical weldment, and n represents the sequence number of the temperature change value in the temperature subsequence to be analyzed. Indicates the n+1th temperature change value in the temperature subsequence to be analyzed. Indicates the nth temperature change value in the temperature subsequence to be analyzed, Represents the absolute value function.

[0080] In the calculation formula of the degree of temperature change regularity, the greater the difference between two adjacent temperature change values, the worse the stability of the temperature change value, the worse the temperature change uniformity of the temperature subsequence to be analyzed, and the worse the temperature change regularity of the temperature subsequence to be analyzed. Therefore and It shows a negative correlation, that is, the greater the difference between two adjacent temperature change values, the worse the temperature change regularity of the temperature subsequence to be analyzed.

[0081] In another example, the degree of temperature variation regularity of the temperature subsequence to be analyzed can also be quantified by calculating the variance or standard deviation of all temperature variation values ​​in the temperature subsequence to be analyzed, wherein the variance or standard deviation of all temperature variation values ​​is negatively correlated with the degree of temperature variation regularity.

[0082] So far, this embodiment has obtained the degree of temperature regularity change of each temperature subsequence to be analyzed corresponding to each type of welding temperature in each historical welding part temperature time series.

[0083] S203, determining the temperature increase value of each type of welding temperature at a future moment according to the degree of temperature variation regularity, the difference between each welding temperature of the same type and the welding temperature at a later moment, and the number of welding temperature types corresponding to each historical welded part.

[0084] In this embodiment, the temperature increase value refers to the increase in the welding temperature at a future moment relative to the welding temperature at a current moment. The larger the temperature increase value, the greater the increase in the welding temperature at a future moment based on the welding temperature at the current moment; the greater the degree of temperature change regularity, the stronger the temperature change regularity of the local historical welding temperature, and the higher the importance of the corresponding temperature change, that is, the greater the weight of the temperature change; the difference between each welding temperature of the same type and the welding temperature at the next moment is the basic data for analyzing the temperature increase at a future moment. The greater the difference between the welding temperatures, the greater the temperature increase value at a future moment; the number of welding temperature types can characterize the reliability of the welding temperature of the historical welded parts. The greater the reliability, the less likely it is that the historical welded parts are welded parts that have undergone thermal deformation, which helps to ensure the numerical accuracy of the temperature increase value.

[0085] The above step S203 can be implemented through steps S213 to S223 (not shown in the figure):

[0086] S213, determining the temperature change index of each type of welding temperature of each historical welded part at a future moment according to the degree of temperature change regularity of each temperature subsequence to be analyzed corresponding to each type of welding temperature and the difference between each welding temperature of the same type and the welding temperature at a later moment.

[0087] The above step S213 can be performed by Figure 4 The steps shown achieve:

[0088] S401, for any historical welded part, determine the proportion of the temperature variation regularity degree of each to-be-analyzed temperature subsequence of a single type of welding temperature in the accumulated value of the temperature variation regularity degree.

[0089] The accumulated value of the temperature variation regularity is equal to the accumulated value of the temperature variation regularity of all the temperature subsequences to be analyzed corresponding to a single type of welding temperature, and each type of welding temperature has its corresponding accumulated value of the temperature variation regularity.

[0090] In this embodiment, the larger the proportion, the stronger the regularity of the temperature change of the corresponding temperature subsequence to be analyzed, and the higher the importance of the corresponding temperature change factor. The reason is that the stronger the regularity of temperature change, the relatively stable heat input during the welding process of the welded parts in the corresponding stage, which can more accurately reflect the welding temperature increase of the historical welded parts without thermal deformation.

[0091] It should be noted that in the historical welding process, the welding and cooling processes work together to make the welded parts present a repeated process of heating up and cooling, which helps to avoid problems such as thermal deformation of the welded parts as much as possible. Therefore, welded parts at different processing stages may present similar welding temperatures, and they may have different temperature changes in the future. Based on this, it is necessary to comprehensively analyze the relative stability of the temperature change of each temperature subsequence to be analyzed, that is, to determine the proportion of the temperature change regularity of a single temperature subsequence to be analyzed in the cumulative value of the temperature change regularity, so as to better quantify the temperature change index of each type of welding temperature of each historical welded part at the future moment.

[0092] S402, taking the proportion as the temperature change weight of the corresponding temperature subsequence to be analyzed, and taking the difference between each welding temperature of the same type and the welding temperature at the next moment as the temperature change factor of the corresponding welding temperature of the same type.

[0093] In this embodiment, each type corresponds to the same welding temperature in different welding stages, that is, welding temperatures of the same value can be distributed at different time points in the entire welding process. For the same type of welding temperature, the absolute value of the difference between the welding temperature and the welding temperature at the next moment is taken as the difference, and the difference is taken as the temperature change factor of the corresponding type of welding temperature. Each type of welding temperature can correspond to multiple different temperature change factors.

[0094] S403, determining a temperature change index of each type of welding temperature of each historical welded part at a future moment according to the temperature change weights of each temperature subsequence to be analyzed corresponding to each type of welding temperature and the temperature change factor of each type of welding temperature.

[0095] In this embodiment, after obtaining the temperature change weight and the temperature change factor, the temperature change factor of each type of welding temperature is weighted and summed using the temperature change weight, thereby obtaining the temperature change index of each type of welding temperature of each historical welded part at a future moment. The specific implementation steps of the above step S403 may include:

[0096] In the first step, the product of the temperature change weight of the temperature subsequence to be analyzed of each welding temperature of the same type and the temperature change factor of the corresponding welding temperature is calculated.

[0097] In the second step, the accumulated value of the product of all welding temperatures of the same type is used as a temperature change indicator of the corresponding type of welding temperature at a future moment.

[0098] As an example, the calculation formula for the temperature change index of the jth type of welding temperature of the i-th historical weldment at a future time may be:

[0099] ; In the formula, It represents the temperature change index of the welding temperature of the jth type of the i-th historical weldment at the future moment. M represents the number of welding temperatures corresponding to each type or the number of temperature subsequences to be analyzed. The number of welding temperatures corresponding to the same type is equal to the number of temperature subsequences to be analyzed of the type. m represents the welding temperature sequence number or the temperature subsequence number to be analyzed corresponding to each type. Indicates the degree of temperature variation regularity of the mth temperature subsequence to be analyzed corresponding to the welding temperature of the jth type of the i-th historical weldment, It represents the cumulative value of the temperature variation regularity of all the temperature subsequences to be analyzed corresponding to the welding temperature of the jth type of the i-th historical weldment. represents the temperature change weight of the j-th type of temperature subsequence to be analyzed for the i-th historical weldment, Represents the temperature variation factor of the mth welding temperature of the jth type of the ith historical weldment.

[0100] In the calculation formula of the temperature change index, the temperature change index can characterize the temperature change of each type of welding temperature of the historical welded parts at the next moment. The larger the temperature change index is, the greater the temperature change amplitude of the corresponding type of welding machine temperature at the next moment is. Then, relative to the current welded part, if the current welding temperature is the welding temperature of this type, the welding temperature of the current welded part at the future moment will be greatly increased, that is, the welding temperature at the future moment is higher, the possibility of thermal deformation is greater, and the possibility of cooling the current welded part is greater.

[0101] S223, determining a temperature increase value of each type of welding temperature at a future moment according to a temperature change index of each type of welding temperature of each historical welding part at a future moment and the number of welding temperature types corresponding to each historical welding part.

[0102] The above step S223 can be performed by Figure 5 The steps shown achieve:

[0103] S501, normalize the number of welding temperature types of each historical welded part to obtain an analysis basis index for each historical welded part; and use the ratio of the analysis basis index of a single historical welded part to the cumulative value of the analysis basis index of all historical welded parts as the welding temperature confidence index of the corresponding historical welded part.

[0104] In this embodiment, the greater the number of welding temperature types of the historical welded parts, the lower the possibility that the historical welded parts will be thermally deformed due to the welding temperature exceeding the critical temperature during the historical welding process, and the greater the importance of the analysis results of the welding temperature data of the historical welded parts to the welding temperature of the current welded parts at the future moment. Therefore, the norm function is used to normalize the number of welding temperature types of each historical welded part to obtain the analysis basis index.

[0105] The reason is that the analysis basis index of the welded parts is determined based on the number of welding temperature types that do not exceed the critical temperature when used in combination with coolants during the actual welding process. The more welding temperature types there are, the better the effect of the historical welded parts in dealing with actual welding and coolant treatment. The welding temperature data of the corresponding historical welded parts has a stronger basis for the subsequent analysis of the current welded parts.

[0106] S502, determining the temperature increase value of each type of welding temperature at a future moment according to the welding temperature confidence index and the temperature change index of each historical welding part.

[0107] The above step S502 can be implemented by the following steps:

[0108] First, for any type of welding temperature, a historical welded part having the type of welding temperature is determined as a target historical welded part.

[0109] In this embodiment, historical welds with this type of welding temperature are selected, so that the temperature increase of this type of welding temperature at a future moment can be analyzed based on the selected target historical welds.

[0110] Secondly, calculate the product of the welding temperature confidence index of each target historical weldment and the temperature change index of the welding temperature of the corresponding target historical weldment at the future moment, and use the accumulated value of the products of all target historical weldments as the temperature increase value of the welding temperature of the type at the future moment.

[0111] As an example, the calculation formula for the temperature rise value of the j-th type of welding temperature at a future time may be:

[0112] ; In the formula, represents the temperature increase value of the j-th type of welding temperature at the future moment, I represents the number of target historical welds corresponding to each type of welding temperature, 'Indicates the target historical welding part number corresponding to each type of welding temperature, Indicates 'Analysis basis indicators for target historical welded parts, Indicates 'Welding temperature confidence index of a target historical weldment, Indicates 'The temperature change index of the welding temperature of the jth type of the target historical weldment at the future moment.

[0113] In the calculation formula of the temperature rise value, for each type of welding temperature, since the welding processes of different historical weldments may be different, the welding temperature types of different historical weldments may be different. When analyzing the temperature rise of a single type of welding temperature at a future moment, it is necessary to select the historical weldments with this type of welding temperature as the analysis object; the welding temperature confidence index can be used as the temperature rise analysis weight. The larger the welding temperature confidence index is, the stronger the analysis basis of the corresponding historical weldments is, and the greater the importance of the corresponding temperature change index is; each type of welding temperature has its corresponding temperature rise value. The larger the temperature rise value is, the greater the temperature change amplitude of the corresponding type of welding temperature at the next moment is, and the greater the possibility of exceeding the critical temperature is, and the more it is necessary to use the coolant in advance to avoid thermal deformation and affect the final welding quality.

[0114] So far, this embodiment obtains the temperature increase value of each type of welding temperature at a future time.

[0115] S204, determining a temperature increase value of the welding temperature of the current welding part at a future time, and obtaining the welding temperature of the current welding part at a future time according to the welding temperature of the current welding part and its temperature increase value at a future time.

[0116] In this embodiment, the welded parts at the welding station are easily affected by the heat temperature during the welding process, and each welded part has its corresponding critical temperature. Once the critical temperature is exceeded, its physical properties and mechanical properties will change significantly, resulting in thermal deformation of the welded parts. Thermal deformation will cause the welding position to shift, thereby affecting the welding quality. Therefore, it is necessary to combine the welding temperature of the current welded part and its temperature rise value at a future time to predict the welding temperature of the current welded part at a future time, and judge whether there is a risk of thermal deformation based on the welding temperature at a future time.

[0117] The above step S204 can be implemented through steps S214 to S224 (not shown in the figure):

[0118] S214, determining the temperature increase value of the welding temperature of the current welded part at a future time.

[0119] In this embodiment, the historical and current properties of the weldment itself are consistent, so the welding temperature types that appear during the welding process are also relatively consistent, that is, the welding temperature of the current weldment is included in the welding temperature of each type. Therefore, based on the temperature increase value of each type of welding temperature at the future time, the temperature increase value of the welding temperature of the current weldment at the future time can be determined.

[0120] Specifically, based on the welding temperature of the current weldment, the welding temperature of the type to which the welding temperature of the current weldment belongs is determined, and the temperature increase value of the corresponding type of welding temperature at a future moment is used as the temperature increase value of the welding temperature of the current weldment at a future moment.

[0121] It should be noted that the temperature rise value of each type of welding temperature at the future moment can be used to predict in real time the welding temperature of other welded parts of the same type as the historical welded parts at the future moment. Other welded parts refer to welded parts of the same type except the current welded parts.

[0122] S224, obtaining the welding temperature of the current welding part at a future time according to the welding temperature of the current welding part and the temperature increase value thereof at a future time.

[0123] In this embodiment, the welding temperature of the current weld is obtained in real time by an infrared temperature sensor. Based on the welding temperature of the current weld and the temperature increase value of the welding temperature of the current weld at a future time, the welding temperature of the current weld at a future time can be predicted.

[0124] Specifically, the value obtained by adding the welding temperature of the current welded part and the temperature increase value of the welding temperature of the current welded part at the future moment is used as the welding temperature of the current welded part at the future moment.

[0125] As an example, the calculation formula for the welding temperature of the current welded part at a future time can be:

[0126] ; In the formula, Indicates the welding temperature of the current weldment at a future time. Indicates the welding temperature of the current weldment. Indicates the temperature increase value of the current welding temperature of the welded part at a future time.

[0127] So far, this embodiment obtains the welding temperature of the current welded part at a future moment, which can be used to predict whether the welding temperature of the current welded part at a future moment exceeds the critical temperature, so as to improve the control of the welding displacement device.

[0128] S205, if the welding temperature at the future moment is greater than or equal to the critical temperature, determine the spraying amount of the coolant of the current welded part according to the welding temperature of the current welded part at the future moment.

[0129] In this embodiment, the critical temperature is a parameter of the weldment itself and can be directly obtained. When the welding temperature at a future moment is greater than or equal to the critical temperature, it means that the current weldment will exceed its critical temperature at a future moment, and thermal deformation and other problems are likely to occur, so the current weldment should be sprayed with a relevant coolant; when the welding temperature at a future moment is less than the critical temperature, the current weldment is not sprayed with a coolant.

[0130] After determining that the welding temperature at the future moment is greater than or equal to the critical temperature, it is also necessary to quantify the amount of coolant sprayed based on the situation that the welding temperature at the future moment exceeds the critical temperature. First, the maximum and minimum doses of the coolant spray are obtained, and based on the maximum and minimum doses and the welding temperature at the future moment, the amount of coolant sprayed for the current weldment is determined.

[0131] Specifically, the difference between the welding temperature of the current welded part at a future moment and the critical temperature is calculated, the difference between the two temperatures is normalized, and a spraying amount control coefficient is obtained; the product of the spraying amount control coefficient and a preset spraying amount adjustment reference value is used as the spraying amount adjustment value of the current welded part; wherein the preset spraying amount adjustment reference value is equal to the difference between the maximum coolant spraying amount and the minimum coolant spraying amount; the value obtained by adding the spraying amount adjustment value of the current welded part and the minimum coolant spraying amount is used as the spraying amount of the coolant of the current welded part.

[0132] As an example, the calculation formula for the spraying amount of the coolant of the current weldment can be:

[0133] ; In the formula, Indicates the amount of coolant sprayed on the current weldment. It indicates the minimum dosage of coolant spraying, that is, the minimum coolant spraying amount, P indicates the preset spraying amount adjustment reference value, norm indicates the linear normalization function, Indicates the welding temperature of the current weldment at a future time. Indicates the critical temperature of the current weldment. represents the spraying amount control coefficient, Indicates the current spray volume adjustment value of the weldment.

[0134] It should be noted that compared with manually setting the spraying amount, the coolant spraying amount determined based on the welding temperature at a future moment predicted based on the specific welding situation is more reasonable, which helps to avoid welding thermal deformation or coolant waste, and further improves the welding quality.

[0135] At this point, when the welding temperature at a future moment is greater than or equal to the critical temperature, this embodiment adaptively determines the spraying amount of the coolant of the current weldment.

[0136] After obtaining the spraying amount of the coolant of the current weldment, the spraying instruction is sent to the control module of the rotating main table, and the cooling station is transferred to the current weldment, and the spray cooling process is performed according to the calculated spraying amount.

[0137] The present embodiment provides a positioner for multi-station welding. Compared with the existing manual judgment and adjustment of coolant spraying, the coolant spraying amount is determined by the welding temperature at the future moment, which can effectively avoid thermal deformation of the workpiece caused by high-temperature welding during the welding process, while reducing the insufficient or wasteful use of coolant, and realizing the intelligent rotation of the rotating main table to move the welding station to the cooling station, further improving the welding quality of the positioner for multi-station welding when used for welding.

[0138] A multi-station welding position shifting device embodiment 2:

[0139] This embodiment provides a multi-station welding position changing device, including a processor and a memory, wherein the processor is used to process instructions stored in the memory to implement the following process:

[0140] Acquire a temperature time series of several historical welded parts and a welding temperature of a current welded part; wherein the temperature time series is composed of a plurality of welding temperatures arranged in chronological order and located before a first critical temperature;

[0141] According to each temperature subsequence to be analyzed corresponding to each type of welding temperature in the temperature time series of each historical welded part, the degree of temperature variation regularity of each temperature subsequence to be analyzed is determined; wherein welding temperatures with the same temperature value are determined as welding temperatures of the same type;

[0142] Determine the temperature increase value of each type of welding temperature at a future moment according to the degree of the temperature variation regularity, the difference between each welding temperature of the same type and the welding temperature at a later moment, and the number of welding temperature types corresponding to each historical welded part;

[0143] Determine the temperature increase value of the welding temperature of the current welding part at the future time, and obtain the welding temperature of the current welding part at the future time according to the welding temperature of the current welding part and the temperature increase value at the future time;

[0144] If the welding temperature at the future moment is greater than or equal to the critical temperature, the spraying amount of the coolant of the current welded part is determined according to the welding temperature of the current welded part at the future moment.

[0145] Therefore, the multi-station welding position shifting device provided in this embodiment is essentially a processor device, which is implemented by an internal data processing process. Since the data processing process has been described in detail in the above-mentioned embodiment 1 of the multi-station welding position shifting device, it will not be repeated here.

[0146] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A multi-station welding positioner, characterized in that: The invention comprises a processor and a memory, wherein the processor is used to process instructions stored in the memory to implement the following process: Acquire a temperature time series of several historical welded parts and a welding temperature of a current welded part; wherein the temperature time series is composed of a plurality of welding temperatures arranged in chronological order and located before a first critical temperature; According to each temperature subsequence to be analyzed corresponding to each type of welding temperature in the temperature time series of each historical welded part, the degree of temperature variation regularity of each temperature subsequence to be analyzed is determined; wherein welding temperatures with the same temperature value are determined as welding temperatures of the same type; Determine the temperature increase value of each type of welding temperature at a future moment according to the degree of the temperature variation regularity, the difference between each welding temperature of the same type and the welding temperature at a later moment, and the number of welding temperature types corresponding to each historical welded part; Determine the temperature increase value of the welding temperature of the current welding part at the future time, and obtain the welding temperature of the current welding part at the future time according to the welding temperature of the current welding part and the temperature increase value at the future time; If the welding temperature at the future moment is greater than or equal to the critical temperature, determining the spraying amount of the coolant of the current welded part according to the welding temperature of the current welded part at the future moment; The step of determining the degree of temperature variation regularity of each temperature subsequence to be analyzed according to each temperature subsequence to be analyzed corresponding to each type of welding temperature in each historical welding part temperature time series includes: In the temperature time series, a subsequence consisting of any welding temperature of any type and a number of welding temperatures located before the welding temperature of the type is used as a temperature subsequence to be analyzed for the welding temperature of the type; Determine the degree of temperature variation regularity of each temperature subsequence to be analyzed according to the distribution of temperature variation values ​​in each temperature subsequence to be analyzed corresponding to each type of welding temperature; wherein the temperature variation value is equal to the difference value between two adjacent welding temperatures in the temperature subsequence to be analyzed; The step of determining the degree of temperature change regularity of each temperature subsequence to be analyzed according to the distribution of temperature change values ​​in each temperature subsequence to be analyzed corresponding to each type of welding temperature includes: In each temperature subsequence to be analyzed, the absolute value of the difference between two adjacent temperature change values ​​is calculated as the temperature change difference value; Determine the cumulative value of all temperature change difference values ​​in the same temperature subsequence to be analyzed, and then normalize the cumulative value to obtain a normalized value; Performing negative correlation processing on the normalized values ​​to determine the degree of temperature variation regularity of each temperature subsequence to be analyzed; The step of determining the temperature increase value of each type of welding temperature at a future moment according to the degree of temperature variation regularity, the difference between each welding temperature of the same type and the welding temperature at a later moment, and the number of welding temperature types corresponding to each historical welded part, comprises: According to the degree of temperature variation regularity of each temperature subsequence to be analyzed corresponding to each type of welding temperature and the difference between each welding temperature of the same type and the welding temperature at the next moment, determine the temperature variation index of each type of welding temperature of each historical welded part at the future moment; Determine the temperature increase value of each type of welding temperature at the future moment according to the temperature change index of each type of welding temperature of each historical welding part at the future moment and the number of welding temperature types corresponding to each historical welding part; The method of determining the temperature change index of each type of welding temperature of each historical welded part at a future moment according to the degree of temperature change regularity of each temperature subsequence to be analyzed corresponding to each type of welding temperature and the difference between each welding temperature of the same type and the welding temperature at the next moment, comprises: For any historical welded part, determine the proportion of the temperature variation regularity degree of each to-be-analyzed temperature subsequence of a single type of welding temperature in the accumulated value of the temperature variation regularity degree, wherein the accumulated value of the temperature variation regularity degree is equal to the accumulated value of the temperature variation regularity degree of all to-be-analyzed temperature subsequences corresponding to the single type of welding temperature; The proportion is used as the temperature change weight of the corresponding temperature subsequence to be analyzed, and the difference between each welding temperature of the same type and the welding temperature at the next moment is used as the temperature change factor of the corresponding welding temperature of the same type; According to the temperature change weights of each temperature subsequence to be analyzed corresponding to each type of welding temperature and the temperature change factors of each type of welding temperature, the temperature change index of each type of welding temperature of each historical weldment at a future moment is determined.

2. A multi-station welding position shifting device according to claim 1, characterized in that: The step of determining the temperature change index of each type of welding temperature of each historical welded part at a future moment according to the temperature change weight of each temperature subsequence to be analyzed corresponding to each type of welding temperature and the temperature change factor of each type of welding temperature comprises: Calculate the product of the temperature change weight of the to-be-analyzed temperature subsequence of each welding temperature of the same type and the temperature change factor of the corresponding welding temperature; The accumulated value of the products of all welding temperatures of the same type is used as a temperature change indicator of the corresponding type of welding temperature at a future moment.

3. A multi-station welding position shifting device according to claim 1, characterized in that: The step of determining the temperature increase value of each type of welding temperature at a future moment according to the temperature change index of each type of welding temperature of each historical welding part at a future moment and the number of welding temperature types corresponding to each historical welding part comprises: The number of welding temperature types of each historical welded part is normalized to obtain the analysis basis index of each historical welded part; the ratio of the analysis basis index of a single historical welded part to the cumulative value of the analysis basis index of all historical welded parts is used as the welding temperature confidence index of the corresponding historical welded part; According to the welding temperature confidence index of each historical welded part and the temperature variation index, the temperature increase value of each type of welding temperature at a future moment is determined.

4. A multi-station welding position shifting device according to claim 3, characterized in that: The step of determining the temperature increase value of each type of welding temperature at a future moment according to the welding temperature confidence index and the temperature change index of each historical welding part comprises: For any type of welding temperature, determine a historical welded part with the type of welding temperature as a target historical welded part; Calculate the product of the welding temperature confidence index of each target historical weldment and the temperature change index of the welding temperature of the corresponding target historical weldment at the future moment, and use the accumulated value of the products of all target historical weldments as the temperature increase value of the welding temperature of the type at the future moment.

5. A multi-station welding position shifting device according to claim 1, characterized in that: The step of determining the spraying amount of the coolant of the current weldment according to the welding temperature of the current weldment at a future moment includes: Calculate the difference between the welding temperature of the current welded part and the critical temperature at the future moment, normalize the difference between the two temperatures, and obtain the spraying amount control coefficient; The product of the spraying amount control coefficient and the preset spraying amount adjustment reference value is used as the spraying amount adjustment value of the current weldment; wherein the preset spraying amount adjustment reference value is equal to the difference between the maximum coolant spraying amount and the minimum coolant spraying amount; The value obtained by adding the spraying amount adjustment value of the current welded part to the minimum coolant spraying amount is used as the spraying amount of the coolant of the current welded part.

6. A multi-station welding position shifting device according to claim 1, comprising a position shifting mechanism for welding, characterized in that: The multi-station welding position shifting device further comprises a coolant spray monitoring device, and the coolant spray monitoring device comprises an infrared temperature sensor and a controller; The infrared temperature sensor signal is connected to the controller, and the infrared temperature sensor is used to obtain a temperature time series of several historical welded parts and a welding temperature of a current welded part; wherein the temperature time series is composed of a plurality of welding temperatures arranged in chronological order and located before a first critical temperature; The controller determines the degree of temperature variation regularity of each temperature subsequence to be analyzed according to each temperature subsequence to be analyzed corresponding to each type of welding temperature in the received temperature time series of each historical welded part; wherein welding temperatures with the same temperature values ​​are determined as welding temperatures of the same type; Determine the temperature increase value of each type of welding temperature at a future moment according to the degree of the temperature variation regularity, the difference between each welding temperature of the same type and the welding temperature at a later moment, and the number of welding temperature types corresponding to each historical welded part; Determine the temperature increase value of the welding temperature of the current welding part at the future time, and obtain the welding temperature of the current welding part at the future time according to the welding temperature of the current welding part and the temperature increase value at the future time; If the welding temperature at the future moment is greater than or equal to the critical temperature, the spraying amount of the coolant of the current welded part is determined according to the welding temperature of the current welded part at the future moment.

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