A screw thread rolling machine on-line detection device and method

Abstract

This invention relates to an online inspection device and method for a screw thread rolling machine, comprising: two openable and closable blocks installed on the left and right sides of a feed guide rail; notches on the workpiece-facing side of the blocks; and a groove formed by the notches when the two blocks are closed, capable of accommodating 1 / 3 to 1 / 2 of the workpiece diameter. A rubbing block, capable of extending and retracting perpendicular to the workpiece's movement direction and rubbing the workpiece within the groove, is located on the opposite side of the groove. A measuring sensor is mounted on the rubbing block. This invention utilizes a guide rail transport chain for bolt workpieces, with blocks on the chain and rubbing blocks used to rub the workpiece to detect its straightness. This simple mechanism allows for rapid online detection of the workpiece's bending degree after heat treatment, preventing excessive bending from affecting thread rolling or straightening processes. Due to its high detection speed, it can inspect each workpiece individually, perfectly keeping pace with the rapid rhythm of thread rolling or straightening machinery, without affecting the processing rhythm of fast-moving workpieces, achieving high-speed and high-precision requirements.

Description

Technical Field

[0001] This invention relates to an online inspection device and method for a screw thread rolling machine. It is a mechanical measuring device and method used to quickly inspect and measure the screw portion of all workpieces on the conveyor chain during the thread rolling machine's processing. Background Technology

[0002] As product quality requirements increase, so too do the quality requirements for bolts. Before or after threading, the outer diameter of the threaded portion of all workpieces needs to be measured to ensure that the diameter tolerance after threading is within the design range. Furthermore, rod-shaped workpieces are prone to bending after heat treatment and need to be straightened before threading. However, some workpieces with significant bending, once they enter the machining station, not only cannot produce qualified products but also affect the machining tooling, potentially damaging the straightening plate or thread rolling plate, and even damaging the machining equipment. To improve machining quality and prevent damage to tooling and equipment, it is best to inspect all workpieces individually before threading or straightening. However, bolt machining is a highly automated, large-scale process, with the machining of a single bolt typically completed in one to several seconds. Under such a rapid pace, manual inspection of each workpiece is impossible. Therefore, how to inspect each threaded workpiece individually at the fast pace of threading is a problem that needs to be solved. Summary of the Invention

[0003] To overcome the problems of existing technologies, this invention proposes an online inspection device and method for screw thread rolling machines. The device and method utilize a stop block to block the workpiece moving on the conveyor chain slide rail, and then roll the workpiece to measure the change in the equivalent diameter before and after rolling. If the change in equivalent diameter is too large, it indicates that the workpiece is significantly bent and is a defective product.

[0004] The objective of this invention is achieved as follows: an online detection device for a screw thread rolling machine includes: two openable and closable blocks installed on the left and right sides of a feeding guide rail; each block has a notch on the workpiece-facing side; when the two blocks are closed, the notch forms a groove that can accommodate 1 / 3 to 1 / 2 of the workpiece diameter; and a rubbing block is provided on the side opposite to the groove, which can extend and retract along a direction perpendicular to the workpiece movement and rub the workpiece in the groove; the rubbing block is equipped with a measuring sensor.

[0005] Furthermore, the notch can be a straight inclined notch or an arc-shaped notch, and the two blocks can be joined together to form a V-shaped groove or a U-shaped groove.

[0006] Furthermore, the notch is provided with at least one row of rollers.

[0007] Furthermore, the end of the rubbing block is provided with a bevel.

[0008] Furthermore, the rubbing block is divided into a transverse motion block perpendicular to the workpiece movement direction and a longitudinal motion block connected to the transverse motion block that can move perpendicular to the transverse motion block movement direction. The measuring sensor is set on the longitudinal motion block.

[0009] Furthermore, the longitudinal moving block is maintained in an extended state by a spring, and a locking device is provided that can lock the position of the longitudinal moving block when the spring is compressed.

[0010] Furthermore, a retractable positioning block is provided behind the stop block, and the retraction direction of the positioning block is perpendicular to the workpiece movement direction.

[0011] An online inspection method for screw workpieces using the above-mentioned device, the method comprising the following steps:

[0012] Step 1, Workpiece entry: A single screw workpiece slides down the conveyor slide;

[0013] Step 2, clamping: The two stops close together to stop the workpiece from sliding down, and the workpiece enters the groove formed by the notches of the two stops;

[0014] Step 3, rubbing: The lateral moving block of the rubbing block extends out, and under the pressure of the workpiece, the longitudinal moving block retracts and locks in, while rubbing the workpiece in the groove. The rubbing causes the workpiece to rotate around the rotation center line by an angle.

[0015] Step 4, Measurement: The sensor measures the change in diameter of the workpiece before and after rotation. If the change is greater than the specified change, the workpiece is deemed unqualified and separated. If the workpiece is deemed qualified, proceed to the next step.

[0016] Step 5, further processing of the workpiece: The workpiece may undergo further dimensional measurement or enter the thread rolling station for inspection to complete the process.

[0017] Furthermore, the angle at which the workpiece is rotated around the rotation center line is 60 to 120 degrees.

[0018] Furthermore, the further dimensional measurement of the workpiece includes the following sub-steps:

[0019] Sub-step 1: Extend the positioning block;

[0020] Sub-step 2, positioning the workpiece: retract the stop block, causing the workpiece in the groove to move forward a short distance before being stopped by the positioning block;

[0021] Sub-step 3: The locking mechanism opens, causing the longitudinal moving block to extend by the same small distance;

[0022] Sub-step 4: The sensor accurately measures the diameter of the workpiece.

[0023] The advantages and beneficial effects of this invention are as follows: This invention utilizes a guide rail transport chain for bolt workpieces, sets stops on the transport chain, and uses a rubbing block to rub the workpiece to detect its straightness. This simple mechanism allows for rapid online detection of the workpiece's curvature after heat treatment, avoiding interference with thread rolling or straightening processes due to excessive curvature. Because of the high detection speed, each workpiece can be inspected, perfectly keeping pace with the rapid rhythm of thread rolling and straightening machinery, without affecting the processing rhythm of fast-moving workpieces, thus achieving high-speed and high-precision requirements. Attached Figure Description

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] Figure 1 This is a schematic diagram of the device and method described in Embodiment 1 of the present invention, and is a schematic diagram of the block in the open state;

[0026] Figure 2 This is a schematic diagram of the device and method described in Embodiment 1 of the present invention, and a schematic diagram of the closed state of the stop block;

[0027] Figure 3 This is a schematic diagram of the structure of the device and method described in Embodiment 1 of the present invention. Figure 1 A-direction view;

[0028] Figure 4 This is a schematic diagram illustrating the principle of the device described in Embodiment 1 of the present invention for measuring the straightness of a workpiece;

[0029] Figure 5 The V-shaped groove formed by the straight inclined notch described in embodiments two and three of this invention is... Figure 2 Enlarged view of point B in the middle;

[0030] Figure 6 It is the U-shaped groove formed by the arc-shaped notch described in embodiments two and three of the present invention;

[0031] Figure 7 This is a schematic diagram of the structure of the rubbing block described in Embodiment 5 of the present invention, showing the compressed state of the longitudinally moving block;

[0032] Figure 8 This is a schematic diagram of the structure of the rubbing block described in Embodiment 5 of the present invention, showing the state of the longitudinally moving block extended; Detailed Implementation

[0033] Example 1:

[0034] This embodiment is an online testing device for a screw thread rolling machine, such as... Figure 1 , 2As shown in Figure 3, this embodiment includes two openable and closable blocks 201 and 202 installed on the left and right sides of the material conveying guide rail 1. The blocks 2 have notches 2021 and 2022 on the side facing the workpiece. When the two blocks are closed, the groove 203 formed by the notches can accommodate 1 / 3 to 1 / 2 of the diameter of the workpiece 3 (the workpiece is represented by a dashed line in the figure). On the side opposite to the groove, a rubbing block 4 is provided, which can extend and retract along the direction perpendicular to the movement of the workpiece and rub the workpiece in the groove. The rubbing block is equipped with a measuring sensor 5.

[0035] The aforementioned material conveying guide is a commonly used transport chain in bolt processing, consisting of two parallel tracks. These tracks can be two thin rods or plates, such as... Figure 3 As shown.

[0036] The shoulder of the bolt head on the workpiece is hung on the track, and the bolt shank hangs down between two tracks. The tracks are inclined according to transportation requirements so that the workpiece can slide down the tracks automatically by gravity. In this embodiment, a relatively open section of the sliding track is selected, and stops, actuating blocks, and sensors are set up to measure whether the straightness of the workpiece's screw meets the requirements. At the same time, the diameter of the screw portion of the workpiece can also be accurately measured.

[0037] The device described in this embodiment is mainly used to detect the straightness of the screw portion of a workpiece. The method involves using a groove capable of accommodating the outer surface of the screw, placing the screw portion within the groove, and rotating the workpiece within the groove. The change in the equivalent diameter of the workpiece before and after rotation is compared. If the workpiece straightness is acceptable, the change in the equivalent outer diameter will be minimal; if the workpiece is bent or deformed beyond requirements, the equivalent diameter will show a significant change. The equivalent diameter mentioned here refers to the diameter change resulting from measuring the combined dimensional tolerances and form and position tolerances of the screw portion of the workpiece. When the form and position tolerances (mainly straightness) are large, i.e., when the workpiece is relatively bent, the equivalent diameter differs significantly from the dimensional diameter; when the form and position tolerances are small, the equivalent diameter is close to the dimensional diameter.

[0038] The requirement for measuring the equivalent diameter is to measure the diameter of the entire length of the workpiece. For measuring the equivalent diameter of the threaded portion of a bolt workpiece, the length of the measuring groove accommodating the threaded portion should be appropriate to, or equal to, the length of the threaded portion of the workpiece, or slightly longer for either the workpiece or the groove, but the difference should not be excessive. Figure 4 As shown. In Figure 4 The length of the central groove 203 is slightly shorter than the workpiece length, but sufficient to measure the workpiece length. For example... Figure 4 As shown, the screw section of the workpiece is significantly bent (for illustrative purposes). Figure 4(The workpiece bending is quite exaggerated) This is because the equivalent diameter D of the workpiece is significantly larger than the workpiece's dimensional diameter D1. When the workpiece is rotated 90 degrees, the equivalent diameter and the dimensional diameter of the workpiece become equal. Figure 3 As shown,

[0039] The two stops are strip-shaped blocks, respectively located on the left and right sides of the guide rail, and converge towards the center from both sides of the guide rail, as shown below. Figure 1 The direction of the middle arrow 'a' forms a barrier against the workpiece. The end of the barrier has a notch to accommodate the screw portion of the workpiece. The notch can have various shapes, but commonly an inclined surface or a curved surface. When the inclined surfaces of the two notches close together, they form a V-groove, a commonly used outer circular surface positioning shape. Alternatively, the notches of the two blocks can be two curved surfaces, which together form a semi-circular groove when closed.

[0040] The aforementioned rubbing block is positioned on one side of the track, and when the workpiece enters the groove formed by the closing of the stop block, it immediately moves along... Figure 1 The movement in the direction of arrow b causes one surface of the rubbing block to contact the outer surface of the workpiece, thus causing the workpiece to rotate around the central axis of rotation. Figure 2 (The direction of the middle arrow c) is used to determine whether the straightness of the screw section of the workpiece exceeds the tolerance range. To reduce the frictional force when the workpiece rotates, rolling elements can be installed on the stop notch.

[0041] The sensor is used to detect the change in equivalent diameter of the workpiece before and after rubbing, in order to determine the straightness of the workpiece. The sensor can be of various forms, such as strain and angle measurement sensors.

[0042] With slight modifications, this embodiment can also be used to more accurately measure the dimensional tolerance of the screw portion diameter of a workpiece. A positioning block is placed downstream (behind) of the stop. After the workpiece straightness judgment is completed, the stop is removed, and the workpiece moves forward slightly, its path blocked by the positioning block. At the same time, the threading block also moves forward slightly. As long as the sensor positioning is accurate, the dimensional diameter of the screw portion of the workpiece can be accurately measured. This device can be used for online measurement of threaded workpieces after thread rolling, i.e., directly removing the stop, using the positioning block to block the falling workpiece, and performing accurate dimensional measurement. This allows for the classification of workpieces according to tolerances after thread rolling, achieving automated online control of workpiece quality.

[0043] It should be noted that the terms "front", "rear", "left", "right", "upstream" and "downstream" in this embodiment and the following embodiments are determined according to the direction of workpiece movement. That is, the element that is contacted first in the direction of workpiece movement is "front" or "downstream", and the element that is contacted later is "rear" or "downstream". The workpiece is simulated as a vehicle moving forward, and "left" and "right" are determined according to the conventional vehicle movement.

[0044] Example 2:

[0045] This embodiment is an improvement upon the above embodiment, refining the notch details. The notch described in this embodiment is a straight, inclined notch or an arc-shaped notch. When the two blocks are joined, they form a V-shaped groove or a U-shaped groove, as shown below. Figure 3 , 4 As shown.

[0046] The blocks on the left and right sides move towards the center simultaneously and meet in the middle of the guide rail. The straight, inclined notch on the stop block (equivalent to a chamfer) forms a V-shaped groove, as shown. Figure 3 As shown, or as Figure 4 The arc-shaped notch forms a U-shaped groove. Figure 3 , 4 What is displayed is Figure 2 Enlarged view of point B on the demolition guide rail.

[0047] Example 3:

[0048] This embodiment is an improvement upon the above embodiment, refining the notch details. In this embodiment, at least one row of rollers 6 is provided at the notch on the stop block, as shown below. Figure 5 , 6 As shown.

[0049] The function of the rollers is to transform the sliding friction between the workpiece screw and the support blocks on both sides into rolling friction when the screw is being rotated. This makes the workpiece easier to rotate. Figure 5 , 6 As shown, the roller is positioned at the point where the straight inclined notch or the arc notch contacts the workpiece.

[0050] because Figure 5 , 6 This is a top view, which doesn't show the thickness of the stop block. Therefore, the row of rollers mentioned refers to the rollers extending along the thickness of the stop block, but... Figure 5 , 6 You can only see one roller, or rather, a row of rollers.

[0051] Example 4:

[0052] This embodiment is an improvement upon the above embodiment, a refinement of the rubbing block. In this embodiment, the rubbing block has a beveled surface 401 at its end. Figure 5 , 6 As shown.

[0053] When the rubbing block moves along arrow b (see...) Figure 5 , 6During movement, it generates a rubbing effect on the workpiece, and the inclined surface at the end of the rubbing block can gradually increase the rubbing force, making the workpiece easier to rotate.

[0054] Example 5:

[0055] This embodiment is an improvement upon the above embodiment, refining the details regarding the rubbing block. In this embodiment, the rubbing block is divided into a transverse motion block 402 perpendicular to the workpiece's movement direction, and a longitudinal motion block 403 connected to the transverse motion block and capable of moving perpendicular to the transverse motion block's movement direction. The measuring sensor is mounted on the longitudinal motion block. Figure 7 , 8 As shown.

[0056] In this embodiment, the rubbing block is divided into two parts. One part performs lateral movement, which means that the direction of movement is perpendicular to the direction of movement of the workpiece on the guide rail. Figure 7 , 8 The direction of the middle arrow b, this direction is... Figure 2 , 3 The direction of motion of the rubbing block as it enters the workpiece and rubs the workpiece is consistent; that is, the rubbing block moves along the workpiece's trajectory. The longitudinal motion refers to the rubbing block's ability to move along the workpiece's path to provide pressure on the workpiece, such as... Figure 7 , 8 The direction indicated by the middle arrow d.

[0057] When the rubbing block comes into contact with the workpiece, the inclined surface on the rubbing block rubs the workpiece. To adjust the force, a spring can be set in the longitudinal movement so that the rubbing block can press the workpiece and control the force of pressing the workpiece. At the same time, it can prepare for accurate measurement of the workpiece diameter.

[0058] Example 6:

[0059] This embodiment is an improvement upon the above embodiment, a refinement of the longitudinal moving block. The longitudinal moving block in this embodiment is equipped with a spring to maintain its extended state, and a locking device 405 that locks the position of the longitudinal moving block when the spring is compressed. Figure 7 , 8 As shown.

[0060] Figure 7 , 8The spring in the middle is a compression spring that provides pressure on the workpiece. During the rubbing process, the pressure provided by the inclined surface of the rubbing block is used. A locking device can be set between the longitudinal and transverse moving blocks. That is, during the rubbing process, the longitudinal moving block cannot move relative to the transverse moving block. The pressure of the inclined surface of the rubbing block gradually increasing on the workpiece is fully utilized. When the pressure reaches a certain level, the locking mechanism is released for measurement to achieve the function of detecting the straightness of the workpiece.

[0061] Example 7:

[0062] This embodiment is an improvement upon the above embodiment, refining the stop block. In this embodiment, a retractable positioning block 7 is further provided behind the stop block. The retraction direction of the positioning block is perpendicular to the workpiece movement direction. Figure 7 , 8 The direction indicated by arrow e.

[0063] The positioning block is also a telescopic moving component, mainly used for measuring the diameter of the workpiece. After the workpiece passes the bending test, a more accurate dimensional measurement can be performed. Diameter measurement requires measurement at two points relative to the outer circle, which cannot be achieved using V-grooves or U-grooves. Therefore, this embodiment employs a positioning block, providing a flat surface to form two opposing measurement points relative to the surface of the rubbing block, enabling precise dimensional measurement.

[0064] The positioning block can extend onto the guide rail after measuring the workpiece's bending, blocking its path. After the block retracts, the workpiece moves forward slightly, only to be stopped again by the positioning block. At this point, the longitudinal moving block on the rubbing block extends, maintaining pressure on the workpiece. Figure 8 As shown, the diameter and tolerance of the workpiece can be obtained by using the relative measurement method.

[0065] Example 8:

[0066] This embodiment is an online inspection method for screw workpieces using the device described in the above embodiment. The steps of the method are as follows:

[0067] Step 1, Workpiece entry: A single screw workpiece slides down the conveyor slide.

[0068] When workpieces move along the track, they may be one after another, or there may be a certain distance between them. This embodiment requires that there be a certain interval between workpieces when they enter the inspection area, so as to allow a short period of time for inspection.

[0069] Step 2, clamping: The two stops close together to stop the workpiece from sliding down, and the workpiece enters the groove formed by the notches of the two stops.

[0070] When the workpiece moves near the two stops, the two stops close together, forming a V-shaped or U-shaped groove, blocking the workpiece's path. The workpiece then enters the V-shaped or U-shaped groove. Entering the V-shaped or U-shaped groove is equivalent to positioning the workpiece for measurement.

[0071] Step 3, rubbing: The lateral moving block of the rubbing block extends out, and under the pressure of the workpiece, the longitudinal moving block retracts and locks in, while rubbing the workpiece in the groove. The rubbing causes the workpiece to rotate around the rotation center line by an angle.

[0072] The purpose of rubbing the workpiece is to determine its straightness. If the straightness of the workpiece meets the requirements, the equivalent diameter will not change much before and after rubbing. Conversely, if the equivalent diameter changes significantly after rubbing, it indicates that the workpiece is bent at a large angle, meaning that the straightness of the screw part of the workpiece does not meet the requirements.

[0073] Step 4, Measurement: The sensor measures the change in diameter of the workpiece before and after rotation. If the change is greater than the specified change, the workpiece is deemed unqualified and separated. If the workpiece is deemed qualified, proceed to the next step.

[0074] The measurement process actually begins as soon as the rubbing block comes into contact with the workpiece. If a strain pressure sensor is used, the equivalent diameter change of the workpiece before and after it is rubbed can be determined by measuring the pressure change of the rubbing block on the workpiece before and after it is rubbed, thereby determining whether the workpiece's curvature is up to standard.

[0075] Step 5, further processing of the workpiece: The workpiece may undergo further dimensional measurement, or the inspection work may be completed after entering the thread rolling station.

[0076] After the workpiece is rolled, its straightness can be determined by the sensor's measurement results. If the straightness is within the acceptable range, thread rolling or straightening can continue. If the straightness is unacceptable, the unacceptable workpiece must be removed from the processing sequence. To improve processing accuracy, after checking the workpiece's straightness, its diameter can be measured further, providing better data support for the thread rolling process and thus improving processing precision. There are various measurement methods; these facilities for checking workpiece straightness can be used to measure the workpiece's diameter.

[0077] Example 9:

[0078] This embodiment is an improvement on the above embodiment, and is a refinement of the above embodiment regarding the rotation angle of the rubbing workpiece around the rotation center line. The rotation angle of the rubbing workpiece around the rotation center line in this embodiment is 60~120 degrees.

[0079] Typically, hot-worked bolt blanks are prone to bending, meaning the screw section bends into a wavy shape. This deformation is relatively easy to identify; simply rub the workpiece in the stop block, rotating it 90 degrees, and you can clearly feel the change in the equivalent diameter of the screw. If the screw section of the workpiece exhibits a wavy deformation, this method of rubbing the workpiece and rotating it 90 degrees can also be used to determine the completeness of the workpiece's deformation. However, wavy bending is less common; most bending is arc-shaped.

[0080] Example 10:

[0081] This embodiment is an improvement on the above embodiment, and is a refinement of the above embodiment regarding further dimensional measurement of the workpiece.

[0082] The main purpose of workpiece dimensional measurement is to measure the diameter and tolerance of the screw section. Measuring the workpiece diameter requires finding two corresponding points on the workpiece's diameter line. Two parallel lines are then established through these two points, perpendicular to the diameter line. With these two parallel lines, the workpiece diameter can be measured. Therefore, this embodiment uses a rubbing block and a positioning block parallel to the rubbing block. The rubbing block itself is perpendicular to the workpiece diameter line along the workpiece's movement direction (after rubbing, the inclined plane has passed through the workpiece, and the latter part no longer has an inclined plane). Thus, the two parallel lines (the two planes of the rubbing block and the positioning block) can accurately measure the diameter of the workpiece's screw section. Further dimensional measurement of the workpiece described in this embodiment includes the following sub-steps:

[0083] Sub-step 1: Extend the positioning block;

[0084] The positioning block is located behind the stop block, so the positioning block will not affect the workpiece when the stop block is closed. Therefore, in order to save time, the positioning block can also extend at the same time as the stop block extends.

[0085] Sub-step 2, positioning the workpiece: retract the stop block, causing the workpiece in the groove to move forward a short distance before being stopped by the positioning block.

[0086] To address the issue of inaccurate positioning of V-grooves and U-grooves, this embodiment replaces the V-grooves and U-grooves with a positioning block to form a reference for measuring the diameter. The diameter of the workpiece is then measured using a relative measurement method. However, after the two blocks separate, the workpiece loses its support and falls naturally, advancing a short distance before being quickly blocked by the positioning block.

[0087] Sub-step 3: The locking mechanism opens, causing the longitudinal moving block to extend by the same short distance.

[0088] The locking mechanism is typically locked during the thread rolling process to fix the lateral and longitudinal moving blocks together, generating the rolling action of the screw. However, when the workpiece falls onto the positioning block, the rolling block should follow. At this point, the locking mechanism unlocks, allowing the longitudinal moving block to follow the workpiece forward and move forward under the action of a spring. Figure 7 , 8 As shown by arrow d.

[0089] Sub-step 4: The sensor accurately measures the diameter of the workpiece.

[0090] The sensor accurately measures the workpiece and calculates its diameter precisely by comparing it with a database.

[0091] Finally, it should be noted that the above is only used to illustrate the technical solution of the present invention and not to limit it. Although the present invention has been described in detail with reference to the preferred arrangement, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of the present invention (such as the dynamic movement mode of each moving part, the form and application mode of the sensor, the sequence of steps, etc.) without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. An online inspection method for screw workpieces, the apparatus used in the method comprising: Two openable stop blocks are installed on the left and right sides of the material conveying guide rail. Each stop block has a notch on the workpiece-facing side. When the two stop blocks are closed, the notch forms a measuring groove that can accommodate 1 / 3 to 1 / 2 of the workpiece diameter. The length of the measuring groove accommodating the workpiece screw portion is adapted to the length of the workpiece screw portion. A rubbing block is provided on the opposite side of the measuring groove, capable of extending and retracting along a direction perpendicular to the workpiece's movement to rub the workpiece within the measuring groove. A measuring sensor is mounted on the rubbing block. The notch is a straight, inclined notch or an arc-shaped notch. When the two stop blocks are closed, they form a V-shaped groove or a U-shaped groove. The notch has at least one row of rollers; the end of the rubbing block has an inclined surface; the rubbing block is divided into a transverse moving block perpendicular to the workpiece movement direction and a longitudinal moving block connected to the transverse moving block that can move perpendicular to the transverse moving block movement direction; the measuring sensor is set on the longitudinal moving block; the longitudinal moving block is maintained in an extended state by a spring and is provided with a locking device that can lock the position of the longitudinal moving block when the spring is compressed; a telescopic positioning block is also provided behind the stop block, and the telescopic direction of the positioning block is perpendicular to the workpiece movement direction. The method is characterized by the following steps: Step 1, Workpiece entry: A single screw workpiece slides down the conveyor slide; Step 2, Clamping: The two stops close together to stop the workpiece from sliding down, and the workpiece enters the measuring groove formed by the notches of the two stops; Step 3, rubbing: The lateral moving block of the rubbing block extends out, and under the pressure of the workpiece, the longitudinal moving block retracts and locks in, while rubbing the workpiece in the measuring groove. The rubbing causes the workpiece to rotate around the rotation center line by an angle. Step 4, Measurement: The measuring sensor measures the change in diameter of the workpiece before and after rotation. If the change is greater than the specified change, the workpiece is deemed unqualified and separated. If the workpiece is deemed qualified, proceed to the next step. Step 5, further processing of the workpiece: The workpiece is further measured in size, or the inspection work is completed after the thread rolling process.

2. The online detection method according to claim 1, characterized in that, The aforementioned rubbing motion causes the workpiece to rotate around the center line of rotation by an angle of 60 to 120 degrees.

3. The online detection method according to claim 2, characterized in that, Further dimensional measurement of the workpiece includes the following sub-steps: Sub-step 1: Extend the positioning block; Sub-step 2, positioning the workpiece: retract the stop block, causing the workpiece in the measuring groove to move forward a short distance before being stopped by the positioning block; Sub-step 3: The locking mechanism is opened, causing the longitudinal moving block to extend by the same small distance; Sub-step 4: The measuring sensor accurately measures the diameter of the workpiece.

Images