A trigger type automatic tool alignment method for a numerical control lathe

Abstract

The application discloses a trigger type automatic tool setting method for a numerical control lathe, and relates to the technical field of mechanical processing automation and numerical control processing control, and comprises the following steps: collecting a continuous displacement change track in a tool setting feeding process, and synchronously recording displacement fluctuation conditions of each time position before and after triggering; and constructing a vibration change record according to time sequence. The application converts trigger determination from a single time position to process determination based on a continuous time range by constructing the vibration change record and identifying a stable transition interval, avoids triggering falling in a vibration extreme position, simultaneously combines intermediate time position selection and displacement change amplitude screening, forms a stable trigger reference and restricts a trigger collection range, makes trigger data sources consistent, and thus improves accuracy and repeat consistency of tool setting results.

Description

Technical Field

[0001] This invention relates to the fields of machining automation and CNC machining control technology, specifically to a trigger-based automatic tool setting method for CNC lathes. Background Technology

[0002] Triggered automatic tool setting for CNC lathes refers to a process where, during the machining preparation stage, a detection device or reference element with trigger response characteristics is installed on the machine tool. When the tool moves along a predetermined path and contacts the reference position, the system instantly generates a trigger signal, automatically recording the actual position of the tool in the machine tool coordinate system. Combined with the preset workpiece coordinate relationship, the tool offset is calculated and written, thus achieving precise calibration of the tool length and position without manual trial cutting or visual judgment. This method essentially utilizes a closed-loop process of contact triggering - signal acquisition - position locking to transform tool setting from an experience-based operation into a repeatable automatic measurement process, significantly improving tool changing efficiency and machining stability while ensuring consistent tool setting accuracy.

[0003] The existing technology has the following shortcomings: In existing technologies, during automatic tool setting and feeding on CNC lathes, the tool's motion is not absolutely stable. It is easily affected by changes in the operating environment and machining rhythm, resulting in extremely low-frequency fluctuations, coupled with imperceptible high-frequency micro-vibrations. During this dynamic process, the actual tool position will continuously fluctuate slightly for a short period. When a trigger detection occurs, the system tends to capture the trigger signal at the instantaneous peak of the vibration, which often deviates from the actual contact position, leading to a deviation in the recorded results. Due to the uncertainty of the vibration state at different times, the trigger position tends to exhibit discrete distribution characteristics, making it difficult to obtain consistent results during repeated tool setting. This can easily lead to unstable tool setting accuracy, and in severe cases, affect the consistency and reliability of subsequent machining dimensions.

[0004] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a trigger-based automatic tool setting method for CNC lathes to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a trigger-based automatic tool setting method for CNC lathes, comprising the following steps: Collect the continuous displacement change trajectory during the tool setting feed process, and simultaneously record the displacement fluctuations at each time position before and after the trigger, and construct a vibration change record in chronological order; Based on vibration change records, the displacement fluctuation amplitude at each time position is segmented and analyzed to identify continuous time segments where the displacement fluctuation amplitude gradually increases and then decreases, and the corresponding stable transition intervals are marked. Based on the stable transition interval, the time position corresponding to the trigger occurrence is reselected, and the trigger record is adjusted from a single time position to the middle time position within the stable transition interval; Around the intermediate time position, the displacement changes at each time position within the stable transition interval are compared and processed. Time positions with displacement changes below the preset threshold are retained and time positions with displacement changes above the preset threshold are removed to form a stable trigger reference. Based on a stable trigger reference, the trigger acquisition time and position in the subsequent tool setting process are adjusted to control the trigger acquisition time and position within a stable transition range, so as to reduce the impact of vibration on the trigger position and improve the consistency of tool setting results.

[0007] Preferably, for the continuous recording of tool displacement changes during tool setting and the unified expression of dynamic changes before and after triggering, a vibration change record including time stamps, displacement values, and displacement fluctuations is constructed to achieve a complete description of the tool's motion state and provide a data foundation for subsequent vibration change segment identification. The steps are as follows: The tool position is collected point by point along the predetermined feed path, and the displacement values ​​corresponding to each collection moment are continuously arranged in time order to form a continuous displacement change trajectory. Based on the time position corresponding to the trigger occurrence, displacement data within the time range before and after the trigger is extracted from the continuous displacement change trajectory. The displacement change is obtained by comparing adjacent time positions, and a sequence of displacement fluctuations is constructed. The sequence of displacement fluctuations is correlated with the trajectory of continuous displacement changes in time and location. The displacement values ​​and displacement changes at the same time and location are combined and uniformly numbered in chronological order to form a composite record. The composite records are organized in chronological order and the corresponding time positions of the triggering are marked. The time positions before the trigger, the time positions corresponding to the trigger, and the time positions after the trigger are distinguished and marked to form a vibration change record.

[0008] Preferably, the displacement change is obtained by comparing the displacement values ​​corresponding to adjacent time positions one by one. The displacement fluctuation sequence is arranged continuously in chronological order. Each time position in the composite record contains a time identifier, displacement value, and displacement change, and is uniformly marked by triggering the corresponding time position.

[0009] Preferably, for identifying the trend of displacement fluctuation amplitude and dividing the time segment in vibration change records, a stable transition interval is formed through segmentation processing and interval calibration, including the following steps: The displacement fluctuation amplitude at each time position is compared along the time sequence of vibration change records. Time positions with the same direction of change are divided into continuous time segments, and the corresponding start and end time positions are recorded. Arrange continuous time segments in chronological order, and connect time segments with increasing displacement fluctuation amplitudes with adjacent time segments with decreasing displacement fluctuation amplitudes to form continuous time intervals. The displacement fluctuation amplitudes at each time point within a continuous time segment are compared sequentially, and continuous time segments that show a process of increasing and decreasing point by point are retained to form the target time segment. The target time range is marked with interval labels, and the start and end time positions are marked. All time positions within the interval are included in the stable transition interval range.

[0010] Preferably, the displacement fluctuation amplitude at each time position within a continuous time segment maintains a single direction of change in time sequence until the point of change direction conversion, and is divided into an increasing displacement fluctuation amplitude interval and a decreasing displacement fluctuation amplitude interval by the point of change direction conversion, with the target time segment covering the continuous range of the increasing interval and the decreasing interval.

[0011] Preferably, the process of converting the time position corresponding to the trigger occurrence to a time position within the stable transition interval involves reconstructing the trigger record through time series extraction and determination of intermediate time positions, including the following steps: The time position corresponding to the triggering occurrence is located along the vibration change record, and compared with the start and end time positions of the stable transition interval. All time positions within the corresponding interval are extracted to form a continuous time series. The continuous time series are sequentially numbered, and the intermediate time positions are determined according to the time positions. The intermediate time positions in the continuous time series are then marked. Extract the displacement value and displacement fluctuation corresponding to the intermediate time position, and establish the correspondence between the time position of the trigger occurrence and the intermediate time position to form an updated trigger record; The time intervals between each time position and the intermediate time position in the continuous time series are sorted, and the time range is represented by combining the start and end time positions of the stable transition interval, thus completing the conversion of the trigger record to the intermediate time position.

[0012] Preferably, the intermediate time position is determined by the sequential arrangement of the continuous time series. The time positions in the continuous time series are numbered sequentially according to time order, and the intermediate time position is determined by the correspondence between the number positions. At the same time, the intermediate time position, together with the start and end time positions of the stable transition interval, constitute the time range representation of the trigger record.

[0013] Preferably, the process of filtering and limiting the time position within the stable transition interval, and forming a stable trigger reference by comparing the displacement change amplitude and organizing the continuity, includes the following steps: The displacement change amplitude at each time position within the stable transition interval is read point by point along the vibration change record and compared with the preset threshold to form the corresponding judgment result; The time positions within the stable transition interval are classified according to the judgment results. The time positions with displacement changes below the preset threshold are extracted and arranged in chronological order to form candidate time series. The time positions in the candidate time series are organized into consecutive time segments, and consecutive time segments containing intermediate time positions are selected. All time positions within a continuous time segment are determined as stable trigger references, and the corresponding start and end time positions are recorded to form a stable trigger reference within a defined range.

[0014] Preferably, continuous time segments in the candidate time series are retained only when they simultaneously satisfy the conditions of continuous time order and include an intermediate time position, and the start and end time positions of the continuous time segments are limited to constrain the time range of stable trigger references.

[0015] Preferably, for the control processing of the trigger acquisition time position within the stable trigger reference time range, the consistency of the trigger time position is achieved through time matching and trigger record adjustment, and the steps are as follows: Establish a time record sequence along the tool setting feed process, and compare the current time position with the starting time position in the stable trigger reference. When the starting time position is reached, enter the trigger acquisition preparation state. By comparing the current time position with the end time position in the stable trigger reference by combining the time record sequence, the time range between the start time position and the end time position is taken as the trigger acquisition time range; Record the time position corresponding to the trigger signal along the trigger acquisition time range, and process the trigger time position to correspond with the middle time position in the stable trigger reference; The system filters the recorded trigger time locations, sorts the time intervals between each trigger time location and the intermediate time location, selects the trigger time location with the smallest time interval as the trigger collection time location, and associates it with the start time location and end time location to form a record.

[0016] The technical effects and advantages provided by the present invention in the above technical solution are as follows: This invention collects the continuous displacement trajectory during the tool setting feed process and constructs a vibration change record containing a time sequence. It continuously tracks the displacement fluctuation amplitude before and after triggering, thereby fully reflecting the dynamic change state of the tool as it approaches the triggering stage. Based on this, by identifying continuous time segments where the displacement fluctuation amplitude gradually increases and then decreases, the triggering determination is extended from a single time position to a stable transition range. This changes the triggering basis from an instantaneous state to a process state, effectively avoiding triggering at the extreme value of vibration fluctuation, thereby improving the accuracy of the triggering position in reflecting the actual contact state.

[0017] This invention further introduces an intermediate time position selection and displacement change amplitude screening mechanism within the stable transition range. By constructing a stable trigger reference and constraining the range of trigger acquisition time positions, the trigger acquisition during subsequent tool setting processes always revolves around the stable transition range. At the same time, time positions where the displacement change amplitude does not meet the constraint conditions are eliminated, thereby ensuring that the trigger data comes from the stable stage of the displacement change process. This ensures that the trigger time positions obtained in multiple tool setting processes have a consistent source, thereby improving the repeatability and consistency of tool setting results and the dimensional stability during the machining process. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0019] Figure 1 This is a flowchart of a trigger-based automatic tool setting method for CNC lathes according to the present invention. Detailed Implementation

[0020] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that the description of this disclosure will be more complete and fully convey the concept of the exemplary embodiments to those skilled in the art.

[0021] This invention provides, for example Figure 1 The method shown is a trigger-based automatic tool setting method for CNC lathes, comprising the following steps: Collect the continuous displacement change trajectory during the tool setting feed process, and simultaneously record the displacement fluctuations at each time position before and after the trigger, and construct a vibration change record in chronological order; During the tool setting process, in order to fully reflect the dynamic changes of the tool as it approaches the trigger position, the tool's position changes are collected point by point over a continuous time period. Combined with the time range before and after the trigger, the displacement change process is recorded in detail, thus forming a vibration change record that reflects the tool's micro-fluctuations. This record is used for subsequent identification of vibration change segments and determination of stable transition intervals. The specific implementation steps are as follows: As the tool moves toward the reference position along the predetermined feed path, the current position of the tool in the machine tool coordinate system is collected point by point at a predetermined fixed time interval. The displacement value corresponding to each collection moment is recorded and arranged continuously in chronological order.

[0022] During the data acquisition process, data is continuously acquired from the start of the tool feed to the point near the trigger position without interruption. This ensures that each time position corresponds to a unique displacement data point. Through continuous acquisition, a displacement sequence covering the entire feed process is formed, thereby constructing a continuous displacement change trajectory that can completely describe the tool's motion path.

[0023] After the continuous displacement trajectory is formed, the time and position of the triggering event are used as the reference starting point. A continuous time interval is selected forward and a continuous time interval is selected backward, and all the displacement data corresponding to the time interval are extracted.

[0024] For the extracted continuous displacement data, the displacement change between two adjacent time positions is calculated sequentially according to the time order. The displacement value of the previous time position is compared with the displacement value of the next time position to obtain the displacement change within each time interval. The displacement change result corresponding to each time position is recorded one by one, thus forming a sequence of displacement fluctuations covering the time range before and after the trigger, so that each time position not only has a displacement value, but also corresponds to a clear displacement change information.

[0025] After obtaining the displacement fluctuation sequence, the time positions in the continuous displacement change trajectory are matched one by one with the time positions in the displacement fluctuation sequence. The displacement values ​​and displacement changes at the same time position are combined, and all time positions are uniformly numbered according to the chronological order, so that each time position contains three pieces of information: time identifier, displacement value, and displacement change.

[0026] During the numbering process, the time order is kept unchanged to ensure the continuity of the data arrangement. In this way, a set of composite records arranged in time order is formed, so that the absolute displacement state of the tool at any time position and the changes in adjacent time can be reflected in the same record at the same time.

[0027] The resulting composite records are organized in chronological order, with the time markers, displacement values, and displacement changes corresponding to each time position arranged continuously. The time position of the trigger is clearly marked in the record, and the time position before the trigger, the time position corresponding to the trigger, and the time position after the trigger are distinguished and marked in the record, thus forming a complete vibration change record.

[0028] The vibration change record unfolds continuously along the time direction, reflecting the displacement change trajectory of the tool before and after the triggering stage and the corresponding displacement fluctuations. This allows the small fluctuations of the tool during the feeding process to be fully presented in the time series, providing a continuous and clear data foundation for subsequent analysis of vibration change trends and determination of stable transition intervals.

[0029] Based on vibration change records, the displacement fluctuation amplitude at each time position is segmented and analyzed to identify continuous time segments where the displacement fluctuation amplitude gradually increases and then decreases, and the corresponding stable transition intervals are marked. After the vibration change record is generated, the displacement fluctuation amplitude corresponding to each time position in the time series is continuously processed and the change process is extracted. The entire vibration change record is divided into multiple time segments with clear change trends. From these segments, continuous time segments with displacement fluctuation amplitude showing a trend of gradually increasing and then gradually decreasing are selected. Based on this, the stable transition interval is determined and calibrated, so that subsequent processing can be carried out within a clear time range. The specific steps are as follows: Following the temporal sequence of the vibration change record, the displacement fluctuation amplitude corresponding to each time position is read point by point, and the time positions are arranged sequentially according to the direction of time progression. During the arrangement process, the displacement fluctuation amplitude of the current time position is compared with the displacement fluctuation amplitude of the immediately preceding time position to determine whether the displacement fluctuation amplitude of the current time position is in an increasing or decreasing state relative to the previous time position. When the displacement fluctuation amplitudes of multiple consecutive time positions maintain the same direction of change, these time positions are divided into the same time segment, and the start and end time positions of the time segment are recorded. At the same time, the change direction information is marked for each time segment, thereby dividing the vibration change record into multiple continuous time segments distinguished by the change direction, so that the change direction of the displacement fluctuation amplitude within each time segment remains consistent.

[0030] After all time segments are divided, they are arranged one by one in chronological order. The end time of each time segment is connected to the start time of the next adjacent time segment. When the change direction of a time segment is an increase in displacement fluctuation amplitude, and the change direction of the next time segment is a decrease in displacement fluctuation amplitude, the two time segments are connected to form a new continuous time segment.

[0031] During the connection process, the starting time of the previous time segment is taken as the starting point of the continuous time segment, and the ending time of the next time segment is taken as the ending point of the continuous time segment, thus constructing a time segment containing the complete change process. This time segment first experiences a stage in which the displacement fluctuation amplitude gradually increases, and then enters a stage in which the displacement fluctuation amplitude gradually decreases.

[0032] After forming continuous time segments, the time positions within each continuous time segment are checked point by point. The displacement fluctuation amplitudes of the starting time position, the intermediate time positions, and the ending time position of the segment are compared sequentially. During the comparison process, it is confirmed that there are no time positions within the segment where the direction of change is reversed. At the same time, it is checked whether the change in displacement fluctuation amplitude between adjacent time positions maintains a continuous and progressive relationship. When all time positions within the segment meet the change process of increasing point by point from the starting position to the intermediate position and decreasing point by point from the intermediate position to the ending position, the continuous time segment is retained as the target time segment.

[0033] Time segments where the direction of change is interrupted or where there is a local reversal are not retained as target time segments, thus ensuring that the screening results only include time segments where the change process is continuous and complete.

[0034] After selecting the target time intervals, the specific position of each target time interval in the vibration change record is marked. The start and end time positions of the target time intervals are clearly marked, and the time range is marked in the vibration change record. At the same time, all time positions within the interval are uniformly included in the stable transition interval, so that the stable transition interval is represented as a continuous interval with a clear start and end point in the vibration change record.

[0035] This calibration process allows the selection of subsequent trigger time locations to be made within a stable transition range, thereby utilizing the continuously changing displacement fluctuation amplitude characteristics within this range to avoid the vibration peak location.

[0036] Based on the stable transition interval, the time position corresponding to the trigger occurrence is reselected, and the trigger record is adjusted from a single time position to the middle time position within the stable transition interval; After the stable transition interval is calibrated, the trigger records, which were originally represented by a single time position, are reconstructed based on the time positions within the stable transition interval. This transforms the trigger records from those representing a single time position into records based on the time positions within the stable transition interval, enabling the trigger records to reflect the overall changes within that interval. The specific steps are as follows: All time positions are retrieved sequentially along the vibration change record. During the retrieval process, the time position corresponding to the trigger occurrence is located, and this time position is compared with the start and end time positions of each stable transition interval. When the time position corresponding to the trigger occurrence is between the start and end time positions of a certain stable transition interval, that stable transition interval is determined as the corresponding interval. After determining the corresponding interval, all time positions from the start to the end time position within that stable transition interval are extracted one by one and rearranged in chronological order to form a continuous time series, thus establishing a clear correspondence between the time position corresponding to the trigger occurrence and the stable transition interval.

[0037] After obtaining the continuous time series, the number of time positions in the series is counted one by one, and a unique sequential number is assigned to each time position according to the chronological order. The numbering is incremented sequentially from the starting time position to the ending time position, and the chronological order is kept unchanged during the numbering process.

[0038] After completing all the numbering, the intermediate time position is determined based on the total number of time positions. When the total number of time positions is odd, the time position in the middle of all the numbers is directly selected as the intermediate time position. When the total number of time positions is even, the two consecutive numbers in the middle position are located, and the time position with the earlier time sequence is selected from the time positions corresponding to these two numbers as the intermediate time position. The above method ensures that the intermediate time position is unique and deterministic throughout the entire stable transition interval.

[0039] After determining the intermediate time position, the displacement value and displacement fluctuation corresponding to the intermediate time position are extracted from the vibration change record, and this intermediate time position is used as the new trigger record time position. At the same time, a correspondence is established between the time position corresponding to the trigger occurrence and the intermediate time position. The time position corresponding to the trigger occurrence and the intermediate time position are retained in the same record. This transforms the trigger record from a single time position to a record format with the intermediate time position of the stable transition interval as the core, so that the trigger record can reflect the continuous change state within the stable transition interval.

[0040] Around the intermediate time position, the time intervals between all time positions within the stable transition interval and the intermediate time position are calculated one by one, and the time positions are arranged in ascending order of time interval. During the arrangement process, the time position with the smallest time interval from the intermediate time position is retained first, and the time positions with gradually increasing time intervals are hierarchically marked. In the subsequent recording process, the intermediate time position is used as the core time point, and combined with the start and end time positions of the stable transition interval, a complete time range representation is formed. This ensures that the trigger record contains both the specific time information of the intermediate time position and the boundary information of the stable transition interval, thereby completing the conversion process from the time position corresponding to the trigger occurrence to the intermediate time position of the stable transition interval.

[0041] Around the intermediate time position, the displacement changes at each time position within the stable transition interval are compared and processed. Time positions with displacement changes below the preset threshold are retained and time positions with displacement changes above the preset threshold are removed to form a stable trigger reference. After determining the intermediate time position, the displacement changes at each time position within the stable transition interval are filtered point by point. The time range is then narrowed and limited with the intermediate time position as the center, further transforming the stable transition interval into a continuous time interval containing only displacement changes that satisfy the constraint conditions. This forms a stable triggering reference for subsequent triggering control. The specific steps are as follows: Using the time marker of the intermediate time position in the vibration change record as the center position, a traversal path is established along the time sequence between the start and end time positions of the stable transition interval. During the traversal, the displacement change amplitude data corresponding to each time position is read one by one starting from the start time position, and the time interval relationship between the time position and the intermediate time position is recorded.

[0042] During the reading process, the displacement change amplitude at each time point is compared with the pre-set displacement change amplitude threshold item by item, and the results are marked one by one, so that each time point in the stable transition interval corresponds to a clear judgment result. This judgment result is used to distinguish whether the time point meets the displacement change amplitude constraint condition, thereby providing a complete data foundation for subsequent screening processing.

[0043] After comparing the displacement change amplitudes of all time positions, the time positions within the stable transition interval are grouped according to the judgment results. The time positions with displacement change amplitudes below the preset threshold are extracted one by one and rearranged in chronological order to form a continuous candidate time series. At the same time, the time positions with displacement change amplitudes above the preset threshold are marked one by one and separated from the original time series.

[0044] During the extraction process, each time position that meets the conditions is sequentially numbered to maintain the original temporal relationship of the candidate time series and to ensure that the time positions in the series all come from the stable transition interval, thus forming an initial screening result centered around the intermediate time position.

[0045] After obtaining the candidate time series, the time positions in the series are organized to ensure continuity. Starting from the beginning of the time sequence, the interval relationship between adjacent time positions is checked one by one. When two adjacent time positions maintain a continuous time sequence in the original vibration change record, they are grouped into the same continuous time segment. When there is a discontinuity in the time sequence, the time series is divided at that position to form multiple independent continuous time segments. After all continuous time segments are formed, each time segment is screened one by one. Only continuous time segments containing the middle time position are retained, and all time segments that do not contain the middle time position are removed. This ensures that the final screening results always revolve around the middle time position and maintain the continuity of the time range.

[0046] After determining the continuous time segments containing the intermediate time position, all time positions within the time segment are used as the constitutive range of the stable triggering reference. The start and end time positions of the time segment are clearly recorded, and the intermediate time position is used as the center marker of the time segment for associated recording. The time range is separately marked in the vibration change record, so that the stable triggering reference not only includes the center time position information, but also the complete time range boundary information.

[0047] Through the above processing, the stable transition interval is further defined as a continuous time interval around the intermediate time position that meets the displacement change amplitude constraint condition, thereby forming a stable trigger reference for subsequent trigger adjustment, so that the trigger behavior has a clear basis for time range and can avoid time positions where the displacement change amplitude exceeds the constraint condition.

[0048] Based on a stable trigger reference, the trigger acquisition time and position in the subsequent tool setting process are adjusted to control the trigger acquisition time and position within a stable transition range, so as to reduce the impact of vibration on the trigger position and improve the consistency of tool setting results. After a stable trigger reference is formed, the time range information contained in the stable trigger reference is incorporated into subsequent tool setting processes to constrain and control the trigger acquisition time position. This ensures that the trigger acquisition behavior always falls within the stable transition range in the time dimension, thereby maintaining a consistent trigger time position source during repeated tool setting processes and preventing triggers from occurring in the unstable phase of displacement fluctuations. The specific implementation steps are as follows: At the start of a new tool setting feed, a time recording sequence is established from the moment the tool enters the feed path. Time is continuously counted from zero, and the time progression during the current tool setting feed process is matched with the time range in the stable trigger reference. During the time progression, the current time position is compared with the starting time position in the stable trigger reference one by one. When the current time position reaches the starting time position of the stable trigger reference, the trigger acquisition state is changed from the inactive state to the ready state. In the ready state, the current position of the tool is continuously recorded, while the trigger signal acquisition channel is kept in the standby state, so that the trigger acquisition behavior is consistent with the starting boundary of the stable trigger reference in time.

[0049] After the acquisition is triggered and enters the preparation state, as time continues to advance, the current time position is continuously compared with the end time position in the stable trigger reference. Before the current time position exceeds the end time position, the entire time period corresponding to the current time position is taken as the effective time range of the acquisition. Within this effective time range, the ability to receive trigger signals is maintained for each time position, and the displacement changes of the tool within this time range are continuously recorded.

[0050] During the time progression, once the current time position exceeds the end time position of the stable trigger reference, the trigger acquisition state is immediately terminated, and the trigger acquisition is changed from the ready state to the off state, so that the trigger acquisition time position is always limited to the time range corresponding to the stable trigger reference.

[0051] Within the effective time range of trigger acquisition, the trigger signal at each time position is recorded point by point. When the tool contacts the reference position during the feeding process and generates a trigger signal, the time position corresponding to the trigger signal is recorded. At the same time, the time position is correlated with the middle time position in the stable trigger reference. By recording the time difference between the trigger time position and the middle time position, each trigger acquisition can be associated with the center time position in the stable trigger reference.

[0052] If multiple trigger signals occur within the entire valid time range, all trigger time positions are recorded sequentially, and the time sequence remains unchanged during the recording process, so that the trigger data remains continuous on the time axis.

[0053] After the trigger acquisition is completed, all recorded trigger time positions are processed uniformly. Each trigger time position is analyzed to correspond with the median time position in the stable trigger reference. The time position with the closest time interval to the median time position is selected as the final trigger acquisition time position. At the same time, the final trigger acquisition time position is associated with the start time position and end time position in the stable trigger reference, so that the final trigger acquisition result contains both center time information and time range information.

[0054] Through the above processing, the trigger acquisition time position obtained in each tool setting process is derived from the stable transition range and determined around the middle time position. This ensures that the trigger time position remains consistent across multiple tool setting processes, thereby reducing the impact of vibration on the trigger position and improving the consistency of tool setting results.

[0055] To fully understand the specific implementation of this process, the following example illustrates it in detail: Assume that during a CNC lathe tool setting feed, a stable trigger reference has been obtained, with a corresponding time range of 1.200 seconds (starting time), 1.260 seconds (ending time), and 1.230 seconds (intermediate time). In a subsequent tool setting feed, time recording begins from the feed start point. When the time reaches 1.200 seconds, trigger acquisition enters the preparation state, forming an effective trigger acquisition time range between 1.200 and 1.260 seconds. Within this time range, during the contact between the tool and the reference position, three trigger signals are generated at 1.218 seconds, 1.233 seconds, and 1.248 seconds, respectively, and these three time positions are recorded. Subsequently, these three trigger signals are... The trigger time position was compared with the median time position of 1.230 seconds, and the corresponding time intervals were calculated to be 0.012 seconds, 0.003 seconds, and 0.018 seconds, respectively. Based on this, 1.233 seconds, with the time interval closest to the median time position, was selected as the final trigger acquisition time position. At the same time, this time position was recorded as being within the stable trigger reference range of 1.200 seconds to 1.260 seconds. In this way, in subsequent tool setting processes, the trigger acquisition time range of 1.200 seconds to 1.260 seconds was used as the trigger acquisition time range, and the time position close to 1.230 seconds was used as the final trigger acquisition basis. This ensured that the trigger time position obtained in each tool setting came from the same time range and was selected around the same central time position, so that the tool setting results were consistent in the time dimension.

[0056] This invention collects the continuous displacement trajectory during the tool setting feed process and constructs a vibration change record containing a time sequence. It continuously tracks the displacement fluctuation amplitude before and after triggering, thereby fully reflecting the dynamic change state of the tool as it approaches the triggering stage. Based on this, by identifying continuous time segments where the displacement fluctuation amplitude gradually increases and then decreases, the triggering determination is extended from a single time position to a stable transition range. This changes the triggering basis from an instantaneous state to a process state, effectively avoiding triggering at the extreme value of vibration fluctuation, thereby improving the accuracy of the triggering position in reflecting the actual contact state.

[0057] This invention further introduces an intermediate time position selection and displacement change amplitude screening mechanism within the stable transition range. By constructing a stable trigger reference and constraining the range of trigger acquisition time positions, the trigger acquisition during subsequent tool setting processes always revolves around the stable transition range. At the same time, time positions where the displacement change amplitude does not meet the constraint conditions are eliminated, thereby ensuring that the trigger data comes from the stable stage of the displacement change process. This ensures that the trigger time positions obtained in multiple tool setting processes have a consistent source, thereby improving the repeatability and consistency of tool setting results and the dimensional stability during the machining process.

[0058] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A trigger-based automatic tool setting method for CNC lathes, characterized in that, Includes the following steps: Collect the continuous displacement change trajectory during the tool setting feed process, and simultaneously record the displacement fluctuations at each time position before and after the trigger, and construct a vibration change record in chronological order; Based on vibration change records, the displacement fluctuation amplitude at each time position is segmented and analyzed to identify continuous time segments where the displacement fluctuation amplitude gradually increases and then decreases, and the corresponding stable transition intervals are marked. Based on the stable transition interval, the time position corresponding to the trigger occurrence is reselected, and the trigger record is adjusted from a single time position to the middle time position within the stable transition interval; Around the intermediate time position, the displacement changes at each time position within the stable transition interval are compared and processed. Time positions with displacement changes below the preset threshold are retained and time positions with displacement changes above the preset threshold are removed to form a stable trigger reference. Based on a stable trigger reference, the trigger acquisition time position during subsequent tool setting is adjusted to keep the trigger acquisition time position within a stable transition range.

2. The trigger-type automatic tool setting method for CNC lathes according to claim 1, characterized in that, To construct a vibration change record for continuous recording of tool displacement changes during tool setting and a unified representation of dynamic changes before and after triggering, the following steps are taken: The tool position is collected point by point along the predetermined feed path, and the displacement values ​​corresponding to each collection moment are continuously arranged in time order to form a continuous displacement change trajectory. Based on the time position corresponding to the trigger occurrence, displacement data within the time range before and after the trigger is extracted from the continuous displacement change trajectory. The displacement change is obtained by comparing adjacent time positions, and a sequence of displacement fluctuations is constructed. The sequence of displacement fluctuations is correlated with the trajectory of continuous displacement changes in time and location. The displacement values ​​and displacement changes at the same time and location are combined and uniformly numbered in chronological order to form a composite record. The composite records are organized in chronological order and the corresponding time positions of the triggering are marked. The time positions before the trigger, the time positions corresponding to the trigger, and the time positions after the trigger are distinguished and marked to form a vibration change record.

3. The trigger-type automatic tool setting method for CNC lathes according to claim 2, characterized in that, The displacement change is obtained by comparing the displacement values ​​corresponding to adjacent time positions one by one. The sequence of displacement fluctuations is arranged continuously in chronological order. Each time position in the composite record contains a time identifier, displacement value, and displacement change, and is uniformly marked by triggering the corresponding time position.

4. The trigger-type automatic tool setting method for CNC lathes according to claim 2, characterized in that, To identify the trend of displacement fluctuation amplitude and divide the time segment in vibration change records, stable transition intervals are formed through segmentation processing and interval calibration, including the following steps: The displacement fluctuation amplitude at each time position is compared along the time sequence of vibration change records. Time positions with the same direction of change are divided into continuous time segments, and the corresponding start and end time positions are recorded. Arrange continuous time segments in chronological order, and connect time segments with increasing displacement fluctuation amplitudes with adjacent time segments with decreasing displacement fluctuation amplitudes to form continuous time intervals. The displacement fluctuation amplitudes at each time point within a continuous time segment are compared sequentially, and continuous time segments that show a process of increasing and decreasing point by point are retained to form the target time segment. The target time range is marked with interval labels, and the start and end time positions are marked. All time positions within the interval are included in the stable transition interval range.

5. A trigger-type automatic tool setting method for a CNC lathe according to claim 4, characterized in that, Within a continuous time interval, the displacement fluctuations at each time point maintain a single direction of change in time sequence until the point of change direction conversion. The point of change direction conversion divides the displacement fluctuations into an increasing interval and a decreasing interval. The target time interval covers the continuous range of the increasing and decreasing intervals.

6. A trigger-type automatic tool setting method for a CNC lathe according to claim 4, characterized in that, The process of converting the trigger occurrence time position to a time position within the stable transition interval involves time series extraction and determination of intermediate time positions to reconstruct the trigger record, including the following steps: The time position corresponding to the triggering occurrence is located along the vibration change record, and compared with the start and end time positions of the stable transition interval. All time positions within the corresponding interval are extracted to form a continuous time series. The continuous time series are sequentially numbered, and the intermediate time positions are determined according to the time positions. The intermediate time positions in the continuous time series are then marked. Extract the displacement value and displacement fluctuation corresponding to the intermediate time position, and establish the correspondence between the time position of the trigger occurrence and the intermediate time position to form an updated trigger record; The time intervals between each time position and the intermediate time position in the continuous time series are sorted, and the time range is represented by combining the start and end time positions of the stable transition interval, thus completing the conversion of the trigger record to the intermediate time position.

7. A trigger-type automatic tool setting method for a CNC lathe according to claim 6, characterized in that, The intermediate time position is determined by the sequential arrangement of the continuous time series. The time positions in the continuous time series are numbered sequentially according to time, and the intermediate time position is determined by the correspondence between the number positions. At the same time, the intermediate time position, together with the start and end time positions of the stable transition interval, constitute the time range representation of the trigger record.

8. A trigger-type automatic tool setting method for a CNC lathe according to claim 6, characterized in that, The process of filtering and limiting time positions within the stable transition interval, and forming a stable trigger reference through comparison of displacement change amplitudes and continuity processing, includes the following steps: The displacement change amplitude at each time position within the stable transition interval is read point by point along the vibration change record and compared with the preset threshold to form the corresponding judgment result; The time positions within the stable transition interval are classified according to the judgment results. The time positions with displacement changes below the preset threshold are extracted and arranged in chronological order to form candidate time series. The time positions in the candidate time series are organized into consecutive time segments, and consecutive time segments containing intermediate time positions are selected. All time positions in a continuous time segment are determined as stable trigger references, and the corresponding start and end time positions are recorded to form stable trigger references.

9. A trigger-type automatic tool setting method for a CNC lathe according to claim 8, characterized in that, In the candidate time series, only the time segments that simultaneously satisfy the conditions of continuous time order and include an intermediate time position are retained. The start and end time positions of the continuous time segments are limited to constrain the time range of stable trigger references.

10. A trigger-type automatic tool setting method for a CNC lathe according to claim 8, characterized in that, For the control and processing of the trigger acquisition time position within the stable trigger reference time range, the consistency of the trigger time position is achieved through time matching and trigger record adjustment. The steps are as follows: Establish a time record sequence along the tool setting feed process, and compare the current time position with the starting time position in the stable trigger reference. When the starting time position is reached, enter the trigger acquisition preparation state. By comparing the current time position with the end time position in the stable trigger reference by combining the time record sequence, the time range between the start time position and the end time position is taken as the trigger acquisition time range; Record the time position corresponding to the trigger signal along the trigger acquisition time range, and process the trigger time position to correspond with the middle time position in the stable trigger reference; The system filters the recorded trigger time locations, sorts the time intervals between each trigger time location and the intermediate time location, selects the trigger time location with the smallest time interval as the trigger collection time location, and associates it with the start time location and end time location to form a record.

Images