Extension tolerance zone detection method, controller, detection device and detection system

Abstract

The invention provides an extension tolerance zone detection method, a controller, a detection device and a detection system, and the method comprises the steps: fitting a reference surface based on a plurality of first auxiliary points on a to-be-detected workpiece, and obtaining a theoretical hole center of a threaded hole on the reference surface; fitting an actual circle center of an extension tolerance zone based on a plurality of second auxiliary points on the measurement surface; normally projecting the actual circle center of the extension tolerance zone to the reference plane to obtain a projection circle center of the extension tolerance zone; and obtaining the position degree deviation of the threaded hole based on the extension tolerance zone projection circle center and the theoretical hole center. Compared with the existing detection method, the detection method provided by the invention can quantitatively measure the threaded hole, ensures the measurement accuracy, timely discovers the precision quality problem, provides an adjustment direction for production, and improves the product force.

Description

Technical Field

[0001] The present invention belongs to the technical field of extended tolerance zone detection, and in particular relates to an extended tolerance zone detection method, a controller, a detection device and a detection system. Background Art

[0002] The extended tolerance zone is a concept in geometric tolerance, which indicates the requirement after the measured element is extended for a certain distance. Geometric tolerance is also generally called geometric tolerance, including shape tolerance and position tolerance. Any part is composed of points, lines, and surfaces, which are called elements. The actual elements of the parts after machining always have errors relative to the ideal elements, including shape errors and position errors.

[0003] At present, when the height dimension of the mounting hole corresponding to the component connected by the threaded hole is large, in order to avoid interference between the mounting fastener and the mounting hole of the connected component, it is necessary to increase the extended tolerance zone requirement for the position of the threaded hole.

[0004] For threaded holes with large depth and extended tolerance position requirements, the connected parts usually have high connection strength and good durability requirements, such as: threaded holes for mounting the front and rear subframes of the body-in-white, threaded holes for mounting the engine suspension, etc. When the fasteners are tightened, they interfere with the corresponding threaded holes of the parts, which will cause the parts to be unable to be installed and affect production efficiency. For example, forced tightening will cause fastener wear and insufficient bolt preload, which will not only cause torque decay problems, but may also lead to quality accidents in severe cases. To avoid such problems, it is necessary to conduct strict precision testing of the extended tolerance band of such threaded holes under the installation reference system of the connected parts, timely discover the problem of over-tolerance in precision, and make production adjustments and quality control to prevent defective products from flowing into the downstream production links. Therefore, how to accurately and efficiently measure the extended tolerance band of threaded holes is a key link.

[0005] At present, in the field of automobile manufacturing, the following precision detection methods are used for threaded holes with large depth and extended tolerance band requirements: using open gauge detection to detect the position requirements under the component installation reference system associated with the threaded hole. The principle of this method is as follows: Figure 1 As shown, this method can only perform qualitative detection, that is, detect whether the threaded hole is qualified. If the extended tolerance band of the threaded hole exceeds the tolerance, it is impossible to measure the position deviation direction and the size of the excess of the threaded hole, and it is also impossible to provide reference data for precision adjustment or adaptation; and because the opening inspection fixture detection requires manual operation, the inspection efficiency is low. Summary of the invention

[0006] The present invention provides an extended tolerance zone detection method, a detection device and a detection system to solve the problem that the prior art cannot perform quantitative measurement or inaccurate measurement of threaded holes with large depth and extended tolerance zone requirements.

[0007] An extended tolerance zone detection method is suitable for detecting a threaded hole on a workpiece to be detected, comprising:

[0008] Based on the multiple first auxiliary points on the workpiece to be measured, a reference plane is fitted to obtain a theoretical hole center of the threaded hole on the reference plane;

[0009] Based on multiple second auxiliary points on the measuring surface, the actual center of the extended tolerance zone is fitted;

[0010] Projecting the normal direction of the actual center of the extended tolerance zone onto the reference plane to obtain the projection center of the extended tolerance zone;

[0011] Based on the projection center of the extended tolerance zone and the theoretical hole center, the position deviation of the threaded hole is obtained.

[0012] Preferably, the measuring surface comprises a threaded hole measuring surface;

[0013] The step of fitting the actual center of the extended tolerance zone based on the plurality of second auxiliary points on the measuring surface comprises:

[0014] Fitting a first position circle center based on at least three second auxiliary points on the first threaded hole measuring surface of the threaded hole;

[0015] Fitting a second position circle center based on at least three second auxiliary points on the second threaded hole measuring surface of the threaded hole;

[0016] Determine an extended connection line according to the center of the first position and the center of the second position;

[0017] The intersection point of the extended connection line and the extended tolerance zone position is determined as the actual center of the extended tolerance zone;

[0018] Wherein, the first threaded hole measuring surface and the second threaded hole measuring surface are two threaded hole measuring surfaces with different depths in the threaded hole.

[0019] Preferably, fitting the actual center of the extended tolerance zone based on a plurality of second auxiliary points on the measuring surface comprises:

[0020] The measuring head is adjusted to the extended tolerance zone position of the measuring screw, and the actual center of the extended tolerance zone is fitted based on a plurality of second auxiliary points on the measuring surface of the measuring head.

[0021] Preferably, the measuring surface comprises a cylindrical surface of a cylindrical measuring head or a spherical surface of a spherical measuring head;

[0022] The step of adjusting the measuring head to the extended tolerance zone position of the measuring screw and fitting the actual center of the extended tolerance zone based on a plurality of second auxiliary points on the measuring surface of the measuring head comprises:

[0023] Adjusting the cylindrical measuring head to the extended tolerance zone position of the measuring screw, and fitting the actual center of the extended tolerance zone based on at least three second auxiliary points on the cylindrical surface of the cylindrical measuring head;

[0024] Alternatively, the spherical measuring head is adjusted to the extended tolerance zone position of the measuring screw, and the actual center of the extended tolerance zone is fitted based on at least five second auxiliary points on the spherical surface of the spherical measuring head.

[0025] An extended tolerance zone detection device comprises a measuring screw, a measuring head and a measuring needle;

[0026] The first end of the measuring screw is used to be placed in the threaded hole of the workpiece to be measured, and the second end of the measuring screw is used to display the position of the extended tolerance zone corresponding to the threaded hole;

[0027] The measuring head is mounted on the measuring screw and is located at a position of an extended tolerance zone corresponding to the measuring screw;

[0028] The measuring needle is used to determine the second auxiliary point on the measuring surface of the measuring head and the first auxiliary point on the workpiece to be measured.

[0029] Preferably, the measuring screw comprises a screw body, a fixing portion extending from a first end of the screw body along the axial direction of the screw body, and an adjusting portion extending from a second end of the screw body along the axial direction of the screw body;

[0030] The fixing portion is used to be placed in a threaded hole of the workpiece to be measured;

[0031] The adjusting portion is used to display the position of the extended tolerance zone corresponding to the threaded hole and to assemble the measuring head.

[0032] Preferably, a machined positioning surface is provided on the outer side of the screw body, and a pin hole is provided on the machined positioning surface. The pin hole is used for installing a pin for connecting with a detection auxiliary tool.

[0033] Preferably, the adjusting portion is provided with a slot along the axial direction of the screw body, and the inner wall of the slot is provided with scale lines arranged along the axial direction of the screw body.

[0034] Preferably, the measuring head comprises a cylindrical measuring head;

[0035] The cylindrical measuring head comprises a first observation portion and a truncated cone portion extending from one end of the first observation portion in the axial direction of the first observation portion, a first cylindrical portion extending from one end of the truncated cone portion in the axial direction of the first observation portion, and a second cylindrical portion extending from the center of one end of the first cylindrical portion in the axial direction of the first observation portion;

[0036] The first observation portion is provided with a marking line and an observation hole, wherein the observation hole is located at the position of the marking line, corresponding to the slot, and is used to determine the position of the cylindrical measuring head;

[0037] The first cylindrical portion is provided with a measuring surface for determining a second auxiliary point and fitting the actual center of the extended tolerance zone.

[0038] Preferably, the measuring head comprises a spherical measuring head;

[0039] The spherical measuring head comprises a second observation portion and a spherical portion extending from the second observation portion along the axial direction of the second observation portion;

[0040] The second observation portion is provided with a marking line and an observation hole, wherein the observation hole is located at the position of the marking line and corresponds to the slot, and is used to determine the position of the spherical measuring head;

[0041] The spherical part is provided with a measuring surface for determining the second auxiliary point and fitting the actual center of the extended tolerance zone.

[0042] Preferably, the extended tolerance zone detection device further comprises a locking member, which is assembled on the measuring screw and is used to limit the position of the measuring head.

[0043] An extended tolerance zone detection system comprises a controller and the extended tolerance zone detection device; the controller is connected to a probe of the extended tolerance zone detection device and is used to receive a second auxiliary point on a measuring surface determined by the probe and a first auxiliary point on a workpiece to be measured, and substitute them into the extended tolerance zone detection method.

[0044] A controller comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the extended tolerance zone detection method is implemented when the processor executes the computer program.

[0045] The present invention, based on multiple second auxiliary points on the measuring surface, fits the actual center of the extended tolerance zone, projects the normal of the actual center of the extended tolerance zone onto the reference surface, and obtains the projection center of the extended tolerance zone; based on the projection center of the extended tolerance zone and the theoretical hole center, subtracts the coordinates of the projection center of the extended tolerance zone from the coordinates of the theoretical hole center to obtain the position deviation of the threaded hole. Compared with the existing detection methods, this detection method can perform quantitative measurement of the threaded hole, ensure measurement accuracy, promptly discover precision and quality problems, provide adjustment direction for production, and improve product strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a schematic diagram of the principle of using an open gauge to perform extended tolerance zone testing in the prior art;

[0047] Figure 2 is a step diagram of the extended tolerance zone detection method of the present invention;

[0048] Figure 3 It is a schematic diagram of the extended tolerance zone detection method in the present invention;

[0049] Figure 4 is a schematic diagram of the extended tolerance zone detection device in the present invention;

[0050] Figure 5 is an exploded view of the extended tolerance zone detection device of the present invention;

[0051] Figure 6 is a stereogram of the measuring head of the present invention;

[0052] Figure 7 is a stereogram of the measuring screw in the present invention;

[0053] Figure 8 is a three-dimensional diagram of a first structure of an extended tolerance zone detection device in the present invention;

[0054] Fig. 9 yes Figure 8 A cross-sectional view of

[0055] Fig.10 is a perspective view of a second structure of the extended tolerance zone detection device in the present invention;

[0056] Fig.11 yes Fig.10 sectional view of .

[0057] Among them, 1. workpiece to be measured; 2. threaded hole; 3. reference plane; 4. measuring surface; 5. actual center of extended tolerance zone; 6. projection center of extended tolerance zone; 7. center of first position; 8. center of second position; 9. measuring screw; 91. screw body; 92. fixing part; 93. adjustment part; 94. machining positioning surface; 95. pin hole; 96. slot; 97. scale line; 10. measuring head; 101. cylindrical measuring head; 1011. first observation part; 1012. frustum part; 1013. first cylindrical part; 1014. second cylindrical part; 102. spherical measuring head; 1021. second observation part; 1022. spherical part; 11. measuring needle; 12. marking line; 13. observation hole; 14. locking piece. DETAILED DESCRIPTION

[0058] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0059] In the description of the present invention, it should be understood that the terms "longitudinal", "radial", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0060] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0061] The embodiment of the present invention provides a method for detecting an extended tolerance zone, referring to Figure 2 , Figure 3 and Figure 4 The extended tolerance zone detection method is suitable for detecting a threaded hole 2 on a workpiece 1 to be detected, and includes:

[0062] S101: fitting a reference plane 3 based on a plurality of first auxiliary points on the workpiece 1 to be measured, and obtaining a theoretical hole center of the threaded hole 2 on the reference plane 3;

[0063] S102: fitting the actual center 5 of the extended tolerance zone based on a plurality of second auxiliary points on the measuring surface 4;

[0064] S103: Normally projecting the actual center 5 of the extended tolerance zone onto the reference plane 3 to obtain the projection center 6 of the extended tolerance zone;

[0065] S104: Based on the projection center 6 of the extended tolerance zone and the theoretical hole center, the position deviation of the threaded hole 2 is obtained.

[0066] Among them, the position of the threaded hole 2 has an extended tolerance zone requirement. Testing its extended tolerance zone can achieve the purpose of obtaining the position deviation of the threaded hole 2. The position deviation refers to the difference between the actual position of the threaded hole 2 to be tested and the theoretical position, which is used to determine whether the threaded hole 2 is qualified. The first auxiliary point is a measuring point on the workpiece 1 to be tested. For example, when the working condition to be tested is a body sheet metal, the first auxiliary point can be a measuring point on the sheet metal surface of the body sheet metal.

[0067] As an example, in step S101, since the sheet metal surface of the workpiece 1 to be measured is directly used for detection, the theoretical hole center of the threaded hole 2 obtained is not accurate enough. Therefore, it is necessary to first determine multiple first auxiliary points on the workpiece 1 to be measured, and use the program to fit the reference plane 3, so that the theoretical hole center of the threaded hole 2 on the reference plane 3 can be obtained. Specifically, three first auxiliary points are determined on the sheet metal of the workpiece 1 to be measured, and the reference plane 3 is fitted by the program, and the theoretical hole center of the threaded hole 2 is found on the reference plane 3.

[0068] The measuring surface 4 may be a surface on the wall of the threaded hole 2 or a surface on a detection tool.

[0069] As an example, in step S102, multiple second auxiliary points are determined on the measuring surface 4, and the actual center 5 of the extended tolerance zone corresponding to the multiple second auxiliary points is fitted using a program. For example, multiple second auxiliary points are determined on the surface on the wall of the threaded hole 2 or on the surface on the inspection tool, and the multiple second auxiliary points are substituted into the program to obtain the fitted actual center 5 of the extended tolerance zone.

[0070] As an example, in step S103, the actual center 5 of the extended tolerance zone is normally projected onto the reference plane 3 to obtain the extended tolerance zone projection center 6. Specifically, the coordinates of the actual center 5 of the extended tolerance zone are projected onto the reference plane 3 along the normal direction of the reference plane 3 to obtain the extended tolerance zone projection center 6.

[0071] As an example, in step S104, based on the extended tolerance zone projection circle center 6 and the theoretical hole center, the position deviation of the threaded hole 2 is obtained. Specifically, by subtracting the coordinates of the extended tolerance zone projection circle center 6 from the coordinates of the theoretical hole center, the position deviation of the threaded hole 2 of the workpiece 1 to be measured can be obtained, so that it can be concluded whether the extended tolerance zone of the threaded hole 2 of the workpiece 1 to be measured meets the requirements. If the position deviation is within the error range, the extended tolerance zone of the threaded hole 2 of the workpiece 1 to be measured meets the requirements, and the threaded hole 2 is judged to be qualified. If the position deviation is not within the error range, the extended tolerance zone of the threaded hole 2 of the workpiece 1 to be measured does not meet the requirements, and the threaded hole 2 is judged to be unqualified.

[0072] In this embodiment, based on multiple second auxiliary points on the measuring surface 4, the actual center 5 of the extended tolerance zone is fitted, and the actual center 5 of the extended tolerance zone is normally projected onto the reference surface 3 to obtain the projection center 6 of the extended tolerance zone; based on the projection center 6 of the extended tolerance zone and the theoretical hole center, the coordinates of the projection center 6 of the extended tolerance zone are subtracted from the coordinates of the theoretical hole center to obtain the position deviation of the threaded hole 2. Compared with the existing detection methods, this detection method can perform quantitative measurement of the threaded hole 2, ensure measurement accuracy, promptly discover precision and quality problems, and provide adjustment direction for production, thereby improving product strength; secondly, this extended tolerance zone detection method clarifies the process of the program calculating the position deviation of the threaded hole 2, provides programming logic for the measurement program, and improves detection efficiency.

[0073] In one embodiment, referring to Figure 2 and Figure 3 , the measuring surface 4 includes a threaded hole measuring surface;

[0074] In step S102, the actual center 5 of the extended tolerance zone is fitted based on the plurality of second auxiliary points on the measuring surface 4, including:

[0075] A1021: fitting a first position circle center 7 based on at least three second auxiliary points on the first threaded hole measuring surface of the threaded hole 2;

[0076] A1022: fitting a second position circle center 8 based on at least three second auxiliary points on the second threaded hole measuring surface of the threaded hole 2;

[0077] A1023: Determine an extended connection line according to the first position circle center 7 and the second position circle center 8;

[0078] A1024: The intersection of the extended connection line and the extended tolerance zone position is determined as the actual center of the extended tolerance zone 5;

[0079] The first threaded hole measuring surface and the second threaded hole measuring surface are two threaded hole measuring surfaces with different depths in the threaded hole. The extended tolerance zone position is the position reached by the extended tolerance zone calibrated for the threaded hole 2 of the workpiece 1 to be measured.

[0080] As an example, the measuring surface 4 includes a threaded hole measuring surface. Since the three-coordinate device cannot measure the extended tolerance zone position of the threaded hole 2, the actual center 5 of the extended tolerance zone is fitted based on multiple second auxiliary points on the measuring surface 4, including: first, fitting the first position center 7 at at least three second auxiliary points on the first threaded hole measuring surface of the threaded hole 2; then, fitting the second position center 8 at at least three second auxiliary points on the second threaded hole measuring surface of the threaded hole 2; then, determining the extended connecting line based on the first position center 7 and the second position center 8; finally, determining the intersection of the extended connecting line and the extended tolerance zone position as the actual center 5 of the extended tolerance zone. In this example, a disc-type probe is used for measurement in the extended tolerance zone position detection method. At least three second auxiliary points are respectively taken on the first threaded hole measuring surface and the second threaded hole measuring surface of the threaded hole 2 of the workpiece 1 to be measured, and the first position circle center 7 and the second position circle center 8 are fitted. Under the premise that the length of the disc-type probe is allowed, the distance between the first threaded hole measuring surface and the second threaded hole measuring surface is made as large as possible, so that the distance between the first position circle center 7 and the second position circle center 8 in the axial direction of the threaded hole 2 is made as large as possible. The first position circle center 7 and the second position circle center 8 are connected into a straight line as a vector by a program, and one of the position circle centers is translated along the vector direction to the extended tolerance zone position, and the coordinates of the translated circle center are obtained as the actual circle center 5 of the extended tolerance zone, and then the actual circle center 5 of the extended tolerance zone is projected normally onto the reference plane 3 to obtain the extended tolerance zone projection circle center 6. Based on the extended tolerance zone projection circle center 6 and the theoretical hole center, the coordinates of the extended tolerance zone projection circle center 6 are subtracted from the coordinates of the theoretical hole center to obtain the position deviation of the threaded hole 2. The operating principle of this measurement method is shown in Figure 3 Among them, a disc-type stylus is used to determine the auxiliary point, and points can be collected by inserting the needle along the axis of the hole, which solves the problem of accurate point collection of deep holes by three-coordinate equipment. It can avoid large measurement errors caused by needle slippage and avoid needle collision due to the large depth or small diameter of the threaded hole 2 of the workpiece 1 to be measured.

[0081] In one embodiment, referring to Figure 2 , Figure 4 and Figure 6 , based on multiple second auxiliary points on the measuring surface, the actual center of the extended tolerance zone is fitted, including:

[0082] The measuring head 10 is adjusted to the extended tolerance zone position of the measuring screw 9 , and the actual center 5 of the extended tolerance zone is fitted based on a plurality of second auxiliary points on the measuring surface 4 of the measuring head 10 .

[0083] As an example, a detection device is used to perform an extended tolerance zone detection on the threaded hole 2 of the workpiece 1 to be measured. When in use, the measuring screw 9 is inserted into the threaded hole 2. The extended tolerance zone position of the threaded hole 2 can be displayed on the measuring screw 9, and then the measuring head 10 is adjusted to the extended tolerance zone position of the measuring screw 9. Based on multiple second auxiliary points on the measuring surface 4 of the measuring head 10, the actual center 5 of the extended tolerance zone is fitted. Compared with the above-mentioned detection method, the determination of the second auxiliary points can be reduced, and the position deviation calculation procedure of the threaded hole 2 is simplified, thereby improving the detection efficiency of the extended tolerance zone of the threaded hole 2.

[0084] In one embodiment, referring to Figure 2 , Figure 4 and Figure 6 , the measuring surface 4 includes the cylindrical surface of the cylindrical measuring head 101 or the spherical surface of the spherical measuring head 102;

[0085] Based on a plurality of second auxiliary points on the measuring surface 4 of the measuring head 10, the actual center 5 of the extended tolerance zone is fitted, including:

[0086] The cylindrical measuring head 101 is adjusted to the extended tolerance zone position of the measuring screw 9, and the actual center 5 of the extended tolerance zone is fitted based on at least three second auxiliary points on the cylindrical surface of the cylindrical measuring head 101;

[0087] Alternatively, the spherical measuring head 102 is adjusted to the extended tolerance zone position of the measuring screw 9 , and the actual center 5 of the extended tolerance zone is fitted based on at least five second auxiliary points on the spherical surface of the spherical measuring head 102 .

[0088] As an example, the measuring surface 4 includes the cylindrical surface of the cylindrical measuring head 101 or the spherical surface of the spherical measuring head 102. Since the above-mentioned extended tolerance zone detection method needs to be measured with the help of a disc-type probe, other mounting holes are measured by cylindrical needles, spherical needles or three-coordinate probes. Switching back and forth, and measuring a threaded hole 2 requires at least six second auxiliary points to be determined, the measurement process is relatively complicated, and in view of the problem that the opening gauge cannot achieve quantitative detection and some areas rely on manual detection, which is laborious and time-consuming, the actual center 5 of the extended tolerance zone is fitted based on multiple second auxiliary points on the measuring surface 4 of the measuring head 10, including:

[0089] In one example, the cylindrical measuring head 101 is adjusted to the extended tolerance zone position of the measuring screw 9, and the actual center 5 of the extended tolerance zone is fitted based on at least three second auxiliary points on the cylindrical surface of the cylindrical measuring head 101, and then the actual center 5 of the extended tolerance zone is projected normally onto the reference plane 3 to obtain the projection center 6 of the extended tolerance zone, and based on the projection center 6 of the extended tolerance zone and the theoretical hole center, the coordinates of the projection center 6 of the extended tolerance zone are subtracted from the coordinates of the theoretical hole center to obtain the position deviation of the threaded hole 2. Among them, the positions of the at least three second auxiliary points are auxiliary points determined on the cylindrical surface of the cylindrical measuring head 101, and the actual center of the cylindrical surface of the cylindrical measuring head 101, that is, the actual center 5 of the extended tolerance zone, can be fitted by substituting them into the program algorithm.

[0090] In another example, the spherical measuring head 102 is adjusted to measure the extended tolerance zone position of the screw 9, and based on at least five second auxiliary points on the spherical surface of the spherical measuring head 102, the actual center 5 of the extended tolerance zone is fitted, and then the actual center 5 of the extended tolerance zone is normally projected onto the reference plane 3 to obtain the extended tolerance zone projection center 6, and based on the extended tolerance zone projection center 6 and the theoretical hole center, the coordinates of the extended tolerance zone projection center 6 are subtracted from the coordinates of the theoretical hole center to obtain the position deviation of the threaded hole 2. Among them, the positions of the at least five second auxiliary points are auxiliary points determined on the spherical surface of the spherical measuring head 102, and the actual center 5 of the spherical surface of the spherical measuring head 102 can be fitted by substituting them into the program algorithm, that is, the actual center 5 of the extended tolerance zone.

[0091] In this embodiment, a cylindrical measuring head 101 or a spherical measuring head 102 is used, and the center of the measuring surface on the measuring head 10 is used to replace the projection center 6 of the extended tolerance zone, and the three-coordinate measuring needle is used to assist in point sampling. There is no need to switch the measuring needle 11. At least three auxiliary points need to be determined to complete the extended tolerance zone detection, which further simplifies the measurement operation. The principle of the extended tolerance zone detection method in this example is shown in Figure 4 .

[0092] An embodiment of the present invention provides a controller, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, an extended tolerance zone detection method is implemented.

[0093] As an example, a controller is introduced, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, an extended tolerance zone detection method is implemented.

[0094] The embodiment of the present invention provides an extended tolerance zone detection device, referring to Figure 4-11, including a measuring screw 9, a measuring head 10 and a measuring needle 11; the first end of the measuring screw 9 is used to be placed in the threaded hole 2 of the workpiece 1 to be measured, and the second end of the measuring screw 9 is used to display the extended tolerance zone position corresponding to the threaded hole 2; the measuring head 10 is assembled on the measuring screw 9 and is located at the extended tolerance zone position corresponding to the measuring screw 9; the measuring needle 11 is used to determine the second auxiliary point on the measuring surface 4 of the measuring head 10 and the first auxiliary point on the workpiece 1 to be measured.

[0095] As an example, an extended tolerance zone position detection device is introduced, which includes a measuring screw 9, a measuring head 10 and a measuring needle 11. When in use, the first end of the measuring screw 9 is first placed in the threaded hole 2 of the workpiece 1 to be measured, and the second end of the measuring screw 9 is used to display the extended tolerance zone position corresponding to the threaded hole 2. The measuring head 10 is assembled on the measuring screw 9 and located at the extended tolerance zone position corresponding to the measuring screw 9. The center of the measuring surface on the measuring head 10 is used to replace the center of the extended tolerance zone projection 6. Then, the measuring needle 11 is used to determine at least three second auxiliary points on the measuring surface 4 of the measuring head 10 and at least three first auxiliary points on the sheet metal of the threaded hole 2 on the workpiece 1 to be measured. According to the at least three second auxiliary points, the measuring surface 4 of the measuring head 10 is used to determine at least three first auxiliary points. The actual center 5 of the extended tolerance zone is fitted by the second auxiliary point, and the reference plane 3 is fitted according to at least three first auxiliary points. Then, according to the designed program setting, the actual center 5 of the extended tolerance zone is normally projected onto the reference plane 3 to obtain the projection center 6 of the extended tolerance zone. Based on the projection center 6 of the extended tolerance zone and the theoretical hole center, the coordinates of the projection center 6 of the extended tolerance zone are subtracted from the coordinates of the theoretical hole center to obtain the position deviation of the threaded hole 2. If the position deviation is within the error range, the extended tolerance zone of the threaded hole 2 of the workpiece 1 to be measured meets the requirements, and the threaded hole 2 is judged to be qualified. If the position deviation is not within the error range, the extended tolerance zone of the threaded hole 2 of the workpiece 1 to be measured does not meet the requirements, and the threaded hole 2 is judged to be unqualified. Among them, the measuring surface 4 of the measuring head 10 can be designed according to the shape of the measuring needle 11. When the shape of the measuring needle 11 is a cylindrical needle or a disc needle, the measuring surface 4 is a cylindrical surface; when the shape of the measuring needle 11 is a spherical needle, the measuring surface 4 is a spherical surface.

[0096] In this example, the center of the measuring surface on the measuring head 10 is used to replace the projection center 6 of the extended tolerance zone, and the three-coordinate probe is used to assist in point sampling. There is no need to switch the probe 11. At least six auxiliary points need to be determined to complete the extended tolerance zone position detection, which reduces the determination of auxiliary points and simplifies the position deviation calculation procedure of the threaded hole 2, thereby improving the detection efficiency. By adjusting the position of the measuring head 10, the extended tolerance zone position of different threaded holes 2 can be adapted to different detection requirements and detection environments. It has good versatility and a wide range of applications, and can effectively solve the current technical problem that threaded holes 2 with large depths and extended tolerance zone requirements cannot be quantitatively measured or are inaccurately measured. It can promptly discover precision and quality problems and provide adjustment directions for production, thereby improving product strength. Both ends of the measuring screw 9 are threaded, one end of the measuring screw 9 is threadedly connected to the measuring head 10, and the extended tolerance zone position of different threaded holes 2 is achieved by adjusting the position of the measuring head 10 on the measuring screw 9, and the other end of the measuring screw 9 is threadedly connected to the threaded hole 2 of the workpiece 1 to be measured; to improve efficiency, the measuring screw 9 only needs to be screwed into the threaded hole 2 to be measured for 3 to 5 turns until the measuring screw 9 is fixed; when the extended tolerance zone is small, so that the measuring head 10 cannot be adjusted to the required position, the measuring screw 9 can be screwed a few more times until the position of the measuring head 10 meets the detection requirements for the extended tolerance zone of the threaded hole 2.

[0097] In one embodiment, referring to Figure 4 , Figure 5 and Figure 7 The measuring screw 9 includes a screw body 91, a fixing portion 92 extending axially from a first end of the screw body 91 along the screw body 91, and an adjusting portion 93 extending axially from a second end of the screw body 91 along the screw body 91; the fixing portion 92 is used to be placed in the threaded hole 2 of the workpiece 1 to be measured; the adjusting portion 93 is used to display the extended tolerance zone position corresponding to the threaded hole 2 and to assemble the measuring head 10.

[0098] As an example, it is introduced that the measuring screw 9 includes a screw body 91, a fixing part 92 and an adjusting part 93. The screw body 91 is connected to the detection auxiliary tool as a reference part. The fixing part 92 is extended from the first end of the screw body 91 along the axial direction of the screw body 91. The size specification of the fixing part 92 is consistent with the threaded hole 2 of the workpiece 1 to be measured, and is used to be placed in the threaded hole 2 of the workpiece 1 to be measured; the adjusting part 93 is extended from the second end of the screw body 91 along the axial direction of the screw body 91, and is used to be placed in the threaded hole 2 of the workpiece 1 to be measured; the adjusting part 93 is used to display the extended tolerance zone position corresponding to the threaded hole 2, and assemble the measuring head 10, adjust the position of the measuring head 10, and make the measuring surface 4 of the measuring head 10 correspond to the extended tolerance zone position. At this time, the center of the measuring surface on the measuring head 10 replaces the projection center 6 of the extended tolerance zone, which provides convenience for obtaining the extended tolerance zone position deviation corresponding to the threaded hole 2.

[0099] In one embodiment, referring to Figure 4-11 A processing positioning surface 94 is provided on the outer side of the screw body 91, and a pin hole 95 is provided on the processing positioning surface 94. The pin hole 95 is used to connect with the detection auxiliary tool through a pin.

[0100] As an example, when using an extended tolerance zone position detection device, after the first end of the measuring screw 9 (i.e., the fixing portion 92) is placed in the threaded hole 2 of the workpiece 1 to be measured, a detection auxiliary tool is needed to fix the measuring screw 9 to ensure that the measuring screw 9 does not shift. A machined positioning surface 94 is provided on the outer side of the screw body 91, and a pin hole 95 is provided on the machined positioning surface 94. The pin hole 95 is used to install a pin and is used to connect with the detection auxiliary tool to facilitate the tightening and loosening of the measuring screw 9, thereby ensuring that the measuring screw 9 is easy to install and does not shift to affect the detection result.

[0101] In one embodiment, referring to Figure 4-11 A slot 96 is provided on the adjusting portion 93 along the axial direction of the screw body 91 , and a scale line 97 is provided on the inner wall of the slot 96 along the axial direction of the screw body 91 .

[0102] As an example, it is introduced that a slot 96 is provided on the adjustment portion 93 along the axial direction of the screw body 91, and a scale line 97 is arranged along the axial direction of the screw body 91 on the inner wall of the slot 96, so that the user can adjust the position of the measuring head 10 and make the measuring surface 4 of the measuring head 10 correspond to the position of the extended tolerance band.

[0103] In this example, two slots 96 can be set on the adjustment part 93. The two slots 96 are symmetrical with the center line of the screw body 91 as the symmetry axis, and the scale lines 97 are set in the slots 96. In this way, the position of the measuring head 10 on the adjustment part 93 can be observed from two directions, which provides convenience for people to adjust the position of the measuring head 10. At the same time, it can also protect the scale lines 97 to avoid direct contact between the measuring head 10 and the scale lines 97 during adjustment, which causes wear of the scale lines 97 and makes it inconvenient to observe the numerical values.

[0104] In one embodiment, referring to Figure 5 , Figure 6 , Figure 8 and Fig. 9The measuring head 10 includes a cylindrical measuring head 101; the cylindrical measuring head 101 includes a first observation portion 1011 and a truncated cone portion 1012 extending from one end of the first observation portion 1011 along the axial direction of the first observation portion 1011, a first cylindrical portion 1013 extending from one end of the truncated cone portion 1012 along the axial direction of the first observation portion 1011, and a second cylindrical portion 1014 extending from the center of one end of the first cylindrical portion 1013 along the axial direction of the first observation portion 1011; a marking line 12 and an observation hole 13 are provided on the first observation portion 1011, and the observation hole 13 is located at the position of the marking line 12, corresponding to the slot 96, and is used to determine the position of the cylindrical measuring head 101; a measuring surface 4 is provided on the first cylindrical portion 1013, which is used to determine the second auxiliary point and fit the actual center 5 of the extended tolerance zone.

[0105] As an example, the measuring head 10 includes a cylindrical measuring head 101; the cylindrical measuring head 101 includes a first observation portion 1011, a truncated cone portion 1012, a first cylindrical portion 1013 and a second cylindrical portion 1014, the first observation portion 1011 is provided with a marking line 12 and an observation hole 13, the marking line 12 represents the extended tolerance zone position of the threaded hole 2 corresponding to the measuring surface 4 of the measuring head 10, the marking line 12 is arranged in a ring shape on the first observation portion 1011, and the observation hole 13 is located at the position of the marking line 12, corresponding to the double-sided slot 96. , used to determine the position of the cylindrical measuring head 101, the conical portion 1012 is extended from one end of the first observation portion 1011 along the axial direction of the first observation portion 1011, the first cylindrical portion 1013 is extended from one end of the conical portion 1012 along the axial direction of the first observation portion 1011, and the second cylindrical portion 1014 is extended from the center of one end of the first cylindrical portion 1013 along the axial direction of the first observation portion 1011, and a measuring surface 4 is provided on the first cylindrical portion 1013 for determining the second auxiliary point and fitting the actual center 5 of the extended tolerance zone.

[0106] In this example, the center of the measuring surface on the cylindrical measuring head 101 is used to replace the projection center 6 of the extended tolerance zone, and then the actual center 5 of the extended tolerance zone is fitted using at least three second auxiliary points determined by the measuring probe 11 on the measuring surface 4 of the first cylindrical portion 1013. Then, according to the designed program setting, the actual center 5 of the extended tolerance zone is normally projected onto the reference plane 3 to obtain the projection center 6 of the extended tolerance zone. Based on the projection center 6 of the extended tolerance zone and the theoretical hole center, the coordinates of the projection center 6 of the extended tolerance zone are subtracted from the coordinates of the theoretical hole center to obtain the position deviation of the threaded hole 2. The measuring surface 4 of the first cylindrical portion 1013 provides a convenient and simple point sampling environment for the three-coordinate device, which can solve the problem that the three-coordinate measuring probe is insufficient in length and limited in motion stroke and cannot sample points for the threaded hole 2 with a larger depth, and can accurately reflect the position deviation of the threaded hole 2 relative to the installation reference system, thereby improving the detection efficiency.

[0107] In one embodiment, referring to Figure 5 , Figure 6 , Fig.10 and Fig.11 The measuring head 10 includes a spherical measuring head 102; the spherical measuring head 102 includes a second observation portion 1021 and a spherical portion 1022 extending from the second observation portion 1021 along the axial direction of the second observation portion 1021; the second observation portion 1021 is provided with a marking line 12 and an observation hole 13, the observation hole 13 is located at the position of the marking line 12, corresponding to the slot 96, and is used to determine the position of the spherical measuring head 102; the spherical portion 1022 is provided with a measuring surface 4, which is used to determine the second auxiliary point and fit the actual center 5 of the extended tolerance zone.

[0108] As an example, it is introduced that the measuring head 10 includes a spherical measuring head 102; the spherical measuring head 102 includes a second observation part 1021 and a spherical part 1022, the second observation part 1021 is provided with a marking line 12 and an observation hole 13, the marking line 12 represents the extended tolerance zone position of the threaded hole 2 corresponding to the measuring surface 4 of the measuring head 10, the observation hole 13 is located at the position of the marking line 12, corresponds to the slot 96, and is used to determine the position of the spherical measuring head 102, the spherical part 1022 extends from the second observation part 1021 along the axial direction of the second observation part 1021, and the spherical part 1022 is provided with a measuring surface 4, which is used to determine the second auxiliary point and fit the actual center 5 of the extended tolerance zone.

[0109] In this example, the center of the measuring surface on the spherical measuring head 102 is used to replace the projection center 6 of the extended tolerance zone, and then the measuring probe 11 is used to determine at least three second auxiliary points on the measuring surface 4 of the spherical part 1022 to fit the actual center 5 of the extended tolerance zone, and then the actual center 5 of the extended tolerance zone is projected normally onto the reference plane 3 according to the designed program settings to obtain the projection center 6 of the extended tolerance zone, and based on the projection center 6 of the extended tolerance zone and the theoretical hole center, the coordinates of the projection center 6 of the extended tolerance zone are subtracted from the coordinates of the theoretical hole center to obtain the position deviation of the threaded hole 2; the measuring surface 4 of the spherical part 1022 provides a convenient and simple point sampling environment for the three-coordinate device, which can solve the problem that the three-coordinate measuring probe is insufficient in length and the movement stroke is limited and it is impossible to sample points for the threaded hole 2 with a larger depth, and can accurately reflect the position deviation of the threaded hole 2 relative to the installation reference system, thereby improving the detection efficiency.

[0110] In one embodiment, referring to Figure 5 , Figure 8 , Fig. 9 , Fig.10 and Fig.11 The extended tolerance zone detection device also includes a locking member 14 , which is assembled on the measuring screw 9 and is used to limit the position of the measuring head 10 .

[0111] As an example, it is introduced that the extended tolerance zone detection device also includes a locking piece 14, which is assembled on the measuring screw 9 and is used to limit the position of the measuring head 10. The locking piece 14 adopts a hexagonal thin nut, and the size is selected according to the specifications of the measuring screw 9; the locking piece 14 can be selected according to the adjustable range of the extended tolerance zone. If the measuring surface 4 on the measuring head 10 cannot be adjusted to the extended tolerance zone position due to the small extended tolerance zone, the locking piece 14 can be removed. If necessary, in order to ensure stable fixation, the upper side of the measuring head 10 can also be fixed with a locking piece 14.

[0112] An embodiment of the present invention provides an extended tolerance zone detection system, including a controller and an extended tolerance zone detection device; the controller is connected to a probe 11 of the extended tolerance zone detection device, and is used to receive a second auxiliary point on a measuring surface 4 and a first auxiliary point on a workpiece to be measured 1 determined by the probe 11, and substitute them into an extended tolerance zone detection method.

[0113] As an example, when in use, the first end of the measuring screw 9 is first placed in the threaded hole 2 of the workpiece 1 to be measured, and the second end of the measuring screw 9 is used to display the extended tolerance zone position corresponding to the threaded hole 2. The measuring head 10 is assembled on the measuring screw 9 and located at the extended tolerance zone position corresponding to the measuring screw 9. The center of the measuring surface on the measuring head 10 is used to replace the projection center 6 of the extended tolerance zone. Then, the measuring needle 11 is used to determine at least three second auxiliary points on the measuring surface 4 of the measuring head 10 and at least three first auxiliary points on the workpiece 1 to be measured, that is, on the sheet metal of the threaded hole 2. The controller fits the actual center 5 of the extended tolerance zone according to the at least three second auxiliary points. And according to at least three first auxiliary points, a reference plane 3 is fitted, and then according to the designed program setting, the actual center 5 of the extended tolerance zone is normally projected onto the reference plane 3 to obtain the extended tolerance zone projection center 6. Based on the extended tolerance zone projection center 6 and the theoretical hole center, the coordinates of the extended tolerance zone projection center 6 are subtracted from the coordinates of the theoretical hole center to obtain the position deviation of the threaded hole 2. If the position deviation is within the error range, the extended tolerance zone of the threaded hole 2 of the workpiece 1 to be measured meets the requirements, and the threaded hole 2 is judged to be qualified. If the position deviation is not within the error range, the extended tolerance zone of the threaded hole 2 of the workpiece 1 to be measured does not meet the requirements, and the threaded hole 2 is judged to be unqualified.

[0114] In this example, the controller cooperates with the extended tolerance zone detection device to implement the extended tolerance zone detection method. The center of the measuring surface on the measuring head 10 is used to replace the extended tolerance zone projection circle center 6, and the three-coordinate probe is assisted in picking points. There is no need to switch the probe 11. At least six auxiliary points need to be determined to complete the extended tolerance zone position detection, which reduces the determination of auxiliary points and simplifies the position deviation calculation procedure of the threaded hole 2, thereby improving the detection efficiency. By adjusting the position of the measuring head 10, the extended tolerance zone position of different threaded holes 2 can be adapted to different detection requirements and detection environments. It has good versatility and a wide range of applications. It can effectively solve the current technical problem that threaded holes 2 with large depths and extended tolerance zone requirements cannot be quantitatively measured or are inaccurately measured, and can promptly discover precision and quality problems and provide adjustment directions for production, thereby improving product strength.

[0115] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for detecting an extended tolerance zone, characterized in that: Suitable for testing threaded holes on workpieces, including: Based on the multiple first auxiliary points on the workpiece to be measured, a reference plane is fitted to obtain a theoretical hole center of the threaded hole on the reference plane; Based on multiple second auxiliary points on the measuring surface, the actual center of the extended tolerance zone is fitted; Projecting the normal direction of the actual center of the extended tolerance zone onto the reference plane to obtain the projection center of the extended tolerance zone; Based on the projection center of the extended tolerance zone and the theoretical hole center, the position deviation of the threaded hole is obtained.

2. The extended tolerance zone detection method according to claim 1, characterized in that: The measuring surface comprises a threaded hole measuring surface; The step of fitting the actual center of the extended tolerance zone based on the plurality of second auxiliary points on the measuring surface comprises: Fitting a first position circle center based on at least three second auxiliary points on the first threaded hole measuring surface of the threaded hole; Fitting a second position circle center based on at least three second auxiliary points on the second threaded hole measuring surface of the threaded hole; Determine an extended connection line according to the center of the first position and the center of the second position; The intersection point of the extended connection line and the extended tolerance zone position is determined as the actual center of the extended tolerance zone; Wherein, the first threaded hole measuring surface and the second threaded hole measuring surface are two threaded hole measuring surfaces with different depths in the threaded hole.

3. The extended tolerance zone detection method according to claim 1, characterized in that: The step of fitting the actual center of the extended tolerance zone based on the plurality of second auxiliary points on the measuring surface comprises: The measuring head is adjusted to the extended tolerance zone position of the measuring screw, and the actual center of the extended tolerance zone is fitted based on a plurality of second auxiliary points on the measuring surface of the measuring head.

4. The extended tolerance zone detection method according to claim 3, characterized in that: The measuring surface comprises a cylindrical surface of a cylindrical measuring head or a spherical surface of a spherical measuring head; The step of adjusting the measuring head to the extended tolerance zone position of the measuring screw and fitting the actual center of the extended tolerance zone based on a plurality of second auxiliary points on the measuring surface of the measuring head comprises: Adjusting the cylindrical measuring head to the extended tolerance zone position of the measuring screw, and fitting the actual center of the extended tolerance zone based on at least three second auxiliary points on the cylindrical surface of the cylindrical measuring head; Alternatively, the spherical measuring head is adjusted to the extended tolerance zone position of the measuring screw, and the actual center of the extended tolerance zone is fitted based on at least five second auxiliary points on the spherical surface of the spherical measuring head.

5. An extended tolerance zone detection device, characterized in that: Including measuring screw, measuring head and measuring needle; The first end of the measuring screw is used to be placed in the threaded hole of the workpiece to be measured, and the second end of the measuring screw is used to display the position of the extended tolerance zone corresponding to the threaded hole; The measuring head is mounted on the measuring screw and is located at a position of an extended tolerance zone corresponding to the measuring screw; The measuring needle is used to determine the second auxiliary point on the measuring surface of the measuring head and the first auxiliary point on the workpiece to be measured.

6. The extended tolerance zone detection device according to claim 5, characterized in that: The measuring screw comprises a screw body, a fixing portion extending from a first end of the screw body along the axial direction of the screw body, and an adjusting portion extending from a second end of the screw body along the axial direction of the screw body; The fixing portion is used to be placed in a threaded hole of the workpiece to be measured; The adjusting portion is used to display the position of the extended tolerance zone corresponding to the threaded hole and to assemble the measuring head.

7. The extended tolerance zone detection device according to claim 6, characterized in that: A processing positioning surface is provided on the outer side of the screw body, and a pin hole is provided on the processing positioning surface. The pin hole is used for installing a pin for connecting with a detection auxiliary tool.

8. The extended tolerance zone detection device according to claim 6, characterized in that: The adjusting portion is provided with a slot along the axial direction of the screw body, and the inner wall of the slot is provided with scale lines arranged along the axial direction of the screw body.

9. The extended tolerance zone detection device according to claim 8, characterized in that: The measuring head comprises a cylindrical measuring head; The cylindrical measuring head comprises a first observation portion and a truncated cone portion extending from one end of the first observation portion in the axial direction of the first observation portion, a first cylindrical portion extending from one end of the truncated cone portion in the axial direction of the first observation portion, and a second cylindrical portion extending from the center of one end of the first cylindrical portion in the axial direction of the first observation portion; The first observation portion is provided with a marking line and an observation hole, wherein the observation hole is located at the position of the marking line, corresponding to the slot, and is used to determine the position of the cylindrical measuring head; The first cylindrical portion is provided with a measuring surface for determining a second auxiliary point and fitting the actual center of the extended tolerance zone.

10. The extended tolerance zone detection device according to claim 8, characterized in that: The measuring head comprises a spherical measuring head; The spherical measuring head comprises a second observation portion and a spherical portion extending from the second observation portion along the axial direction of the second observation portion; The second observation portion is provided with a marking line and an observation hole, wherein the observation hole is located at the position of the marking line and corresponds to the slot, and is used to determine the position of the spherical measuring head; The spherical part is provided with a measuring surface for determining the second auxiliary point and fitting the actual center of the extended tolerance zone.

11. The extended tolerance zone detection device according to claim 5, characterized in that: The extended tolerance zone detection device further comprises a locking member, which is assembled on the measuring screw and is used to limit the position of the measuring head.

12. An extended tolerance zone detection system, characterized in that: It comprises a controller and the extended tolerance zone detection device as described in any one of claims 5-11; the controller is connected to the probe of the extended tolerance zone detection device, and is used to receive the second auxiliary point on the measuring surface determined by the probe and the first auxiliary point on the workpiece to be measured, and substitute them into the extended tolerance zone detection method as described in any one of claims 1-4.

13. A controller comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the extended tolerance zone detection method according to any one of claims 1 to 4 is implemented.

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