Method for measuring and removing eccentricity of porcelain piece and blank of porcelain insulator

Abstract

The invention relates to a method for measuring and removing eccentricity of a porcelain piece and a blank of a porcelain insulator, and belongs to the technical field of insulator quality detection. The method comprises the following steps: positioning a to-be-tested piece; the wall thickness of the to-be-measured piece is measured at different angles, and the eccentric distance of the to-be-measured piece is calculated according to the wall thickness of the to-be-measured piece; and analyzing the eccentric distance according to a preset rejection threshold value, and judging whether the to-be-detected piece needs to be rejected or not. After the porcelain insulator is positioned, the wall thickness of the porcelain insulator at different angles is detected, the eccentric distance is calculated according to the wall thickness measurement result, whether the porcelain insulator needs to be removed or not is judged according to the removal threshold value of the Westgard sigma multi-rule based on quality management, a manufacturer can know the eccentric information of the disc-type suspension porcelain insulator, and the production efficiency is improved. And an elimination scheme is formulated, the consistency of final products is improved, eccentric data can be provided for users, product information is increased, and the market competitiveness is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of insulator quality detection, and in particular relates to a method and a measuring system for measuring and rejecting the eccentricity of porcelain parts and blanks of porcelain insulators. Background Art

[0002] Disc-type suspension porcelain insulators are important equipment components of power transmission and transformation systems. They are widely used in power grid systems such as high-voltage transmission lines and substations, and play a role in mechanical support and power insulation for transmission conductors. The porcelain parts of disc-type suspension porcelain insulators have cylindrical or conical inner holes in structure, and the inner hole and the outer wall should be concentric in structural design. In actual production, there is often eccentricity between the inner hole and the outer wall. Eccentricity will cause uneven force on the final product and reduce the insulation distance on one side. In order to improve product quality, it is necessary to check and remove the eccentricity of the blanks and porcelain parts during production.

[0003] Due to the complex shape of disc-type suspension insulators, there is currently no tool that can directly measure the eccentricity between the inner hole circle and the outer wall circle of a blank or porcelain part. The present invention proposes a method for measuring and rejecting the eccentricity of a porcelain part or blank of a disc-type suspension porcelain insulator, provides a method for calculating the eccentricity, and a rejection threshold that meets the Westgard sigma multi-rule for quality management.

[0004] Specifically, there are the following problems in the existing porcelain insulator measurement work:

[0005] 1. In the traditional method of measuring the eccentricity of porcelain parts and blanks, steel rulers, internal calipers, vernier rulers, etc. are used. During the measurement process, there is a certain damage to the head and inner hole of the blank and there is a large error; the measurement efficiency is low, the operation is difficult, and the labor intensity is high.

[0006] 2. In the traditional measurement method, although the outer wall circle and the inner hole circle can be measured using a vernier ruler and an internal caliper, and the side wall thickness can then be calculated by the difference, it is impossible to determine whether there is a difference in the thickness of the side walls on both sides, and it is impossible to eliminate eccentric products.

[0007] 3. Since the head and inner hole of the cylindrical porcelain part are covered with a layer of porcelain sand, the size of the head and inner hole of the porcelain part cannot be accurately measured using traditional measurement methods.

[0008] 4. When using tools such as steel rulers, vernier rulers, and internal calipers to measure, they are often limited to a certain position. The measurement range is too small and it is impossible to accurately determine whether the product is eccentric. Summary of the invention

[0009] The object of the present invention is to provide a method for measuring and removing the eccentricity of porcelain parts and blanks of porcelain insulators in order to solve the above problems.

[0010] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0011] A method for measuring and removing the eccentricity of a porcelain insulator porcelain part and a blank, wherein the porcelain insulator porcelain part and the blank are both parts to be measured by the method, and the method comprises the following steps:

[0012] Step 1: Position the workpiece to be tested so that the axis of the outer wall of the workpiece to be tested is aligned with the measuring station;

[0013] Step 2: Measure the wall thickness of the test piece at different angles, and calculate the eccentricity of the test piece based on the wall thickness. The calculation method of the eccentricity is as follows:

[0014]

[0015] Where dE is the range of N wall thickness measurement results; max{E i} is the maximum wall thickness in N wall thickness measurements, is the minimum wall thickness in N wall thickness measurements, k is the middle value, and d is the eccentricity;

[0016] Step 3: Analyze the eccentricity of the test piece. When the eccentricity of the test piece exceeds the preset rejection threshold, the test piece is rejected. The method for establishing the rejection threshold is as follows:

[0017]

[0018] Among them, d MAX is the rejection threshold of the tested part, s is the standard deviation of the two-dimensional normal distribution, and P is the probability value obtained by querying the Westgard sigma multi-rule.

[0019] As a further optimization scheme of the present invention, in step 3, the standard deviation of the two-dimensional normal distribution is calculated as follows:

[0020]

[0021] Wherein, d is the average value of the eccentricity of a batch of porcelain parts or blanks calculated in advance.

[0022] A measuring system for implementing the above method comprises a positioning mechanism, a thickness measuring mechanism and a control module, wherein the positioning mechanism is used to perform axial positioning on a workpiece to be measured, the thickness measuring mechanism is used to collect wall thickness data of the workpiece to be measured at different angles, and send the wall thickness data to the control module, after receiving the wall thickness data, the control module obtains the eccentricity of the workpiece to be measured according to the eccentricity calculation method, and determines whether the workpiece to be measured needs to be rejected based on a rejection threshold.

[0023] As a further optimization scheme of the present invention, the system also includes an air supply mechanism and a driving mechanism connected to the control module, the positioning mechanism has a pneumatic actuator, the air supply mechanism is used to make the pneumatic actuator position the outer wall axis of the workpiece to be measured, the thickness measuring mechanism has two thickness measuring components, the driving mechanism is used to place the two thickness measuring components of the thickness measuring mechanism inside and outside the workpiece to be measured, respectively, and make the thickness measuring mechanism and the positioning mechanism rotate relative to each other about the outer wall axis of the workpiece to be measured.

[0024] As a further optimization scheme of the present invention, the positioning mechanism includes a positioning seat, a accommodating cavity arranged inside the positioning seat, an airbag fixed to the upper part of the accommodating cavity, and a carrier plate arranged at the lower part of the accommodating cavity, and the carrier plate can slide along any horizontal direction on the bottom wall of the positioning seat.

[0025] As a further optimization scheme of the present invention, the positioning mechanism also includes a reset member, which is used to reset the carrier plate to the axis center of the positioning mechanism after the wall thickness measurement of each test piece is completed. After resetting, the axis center of the carrier plate coincides with or is close to the axis center of the positioning mechanism.

[0026] As a further optimization scheme of the present invention, the reset member includes a counterweight member located directly below the positioning seat, and a pull rope provided between the counterweight member and the carrier plate. When positioning the workpiece to be tested, the counterweight member moves upward to keep the pull rope loose and the carrier plate in an unconstrained state; after the wall thickness measurement of the workpiece to be tested is completed, the counterweight member moves downward to reset and constrain the carrier plate through the pull rope.

[0027] As a further optimization scheme of the present invention, balls are evenly arranged along the circumferential direction on the bottom of the carrier plate, a guide piece is formed by an upward protrusion at the center of the bottom wall of the positioning seat, and a wire groove corresponding to the pull rope is arranged through the guide piece, and the wire groove passes through the bottom wall of the positioning seat.

[0028] As a further optimization scheme of the present invention, the system also includes a bracket, a load sensor is fixedly provided between the bracket and the positioning seat, and an air cylinder is fixedly provided on the bracket, and the air cylinder is slidably provided under the counterweight, the air supply mechanism includes an air pump, a shunt pipe connected to the air outlet of the air pump, and an air pressure sensor and a three-way valve arranged on the shunt pipe, the airbag and the air cylinder are both connected to the shunt pipe, a clamping component corresponding to the counterweight is provided on the bracket, and a flow blocking component is provided on the branch connecting the shunt pipe and the airbag.

[0029] As a further optimization scheme of the present invention, the driving mechanism includes a lifting assembly and a rotating driving member fixedly mounted at the output end of the lifting assembly, the thickness measuring mechanism includes a mounting frame fixedly mounted at the output end of the rotating driving member, a thickness measuring component of the thickness measuring mechanism is arranged in the middle of the mounting frame, and another thickness measuring component of the thickness measuring mechanism is arranged at one end of the mounting frame, and a counterweight component is provided at the other end of the mounting frame.

[0030] The beneficial effects of the present invention are:

[0031] 1) The present invention detects the wall thickness of the porcelain insulator at different angles through the thickness measuring component, and calculates the eccentricity through the wall thickness measurement result, and the rejection threshold that meets the Westgard Sigma multi-rule of quality management, so that the manufacturer can understand the eccentricity information of the disc-type suspension porcelain insulator, formulate a rejection plan, and improve the consistency of the final product;

[0032] 2) The present invention can automatically measure the wall thickness and eccentricity of porcelain insulators at different heights, and can accurately obtain the size of the porcelain head and inner hole. It has a large measuring range, high measuring efficiency, simple operation, and saves manpower;

[0033] 3) The present invention uses the eccentricity measurement and elimination method to obtain eccentricity data, which can be provided to users who purchase porcelain insulator products, thereby increasing product information and improving market competitiveness;

[0034] 4) The present invention positions the porcelain insulator through the pneumatic actuator of the positioning mechanism, and during positioning, the friction between the carrier plate below the porcelain insulator and the positioning seat is small, so that each porcelain insulator can be moved to the axis of the positioning mechanism, thereby preventing the porcelain insulator from being damaged during the positioning process and improving the measurement accuracy;

[0035] 5) The present invention resets the carrier plate by a reset member after the eccentricity measurement is completed, thereby avoiding the situation where the carrier plate moves to the inner wall of the positioning seat after multiple eccentricity measurements and cannot cooperate with the pneumatic actuator to reset the porcelain insulator;

[0036] 6) In the present invention, when the pneumatic actuator is inflated, the air supply mechanism also inflates the air cylinder to move the counterweight of the reset member upward, thereby avoiding the restraint of the movement of the carrier plate by the deadweight of the counterweight. After the eccentricity measurement is completed, the gas in the air cylinder is discharged through the shunt pipe and the three-way valve, and the counterweight resets the carrier plate by its deadweight, further improving the positioning effect and improving the measurement accuracy.

[0037] 7) When positioning the porcelain insulator, the present invention utilizes the positioning gas source to automatically and synchronously contact the constraints on the porcelain insulator carrier. During the measurement preparation stage and the measurement process, the reset component will not generate any interference force on the carrier. After the measurement, when the positioning of the porcelain insulator is released, the constraint force on the porcelain insulator carrier is automatically and synchronously restored to achieve automatic positioning and resetting. The carrier reset and the porcelain insulator positioning will not interfere with each other, and the reset operation does not require the addition of an additional power source. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 1 is a side cross-sectional schematic diagram of the present invention when measuring the wall thickness E1;

[0039] Figure 2 It is a top view cross-sectional schematic diagram when the present invention measures six wall thicknesses E1-E6 on the circumference;

[0040] Figure 3 It is a top view cross-sectional schematic diagram when the present invention measures eight wall thicknesses E1-E8 on the circumference;

[0041] Figure 4 is a system block diagram of the measurement system of the present invention;

[0042] Figure 5 It is a structural schematic diagram of the measurement system of the present invention in a non-working state;

[0043] Figure 6 It is a schematic diagram of the structure of the measuring system of the present invention in working state;

[0044] Figure 7 It is a schematic diagram of the internal structure of the positioning mechanism of the present invention;

[0045] Figure 8 yes Figure 7 The enlarged view of point A in the middle;

[0046] Fig. 9 yes Figure 7 The enlarged view of point B in the middle;

[0047] Fig.10 yes Figure 7 Enlarged view of point C in the middle;

[0048] Fig.11 It is a side view of the thickness measuring mechanism with a suspension assembly of the present invention.

[0049] In the figure: 1, positioning mechanism; 2, thickness measuring mechanism; 3, air supply mechanism; 4, driving mechanism; 5, bracket; 11, positioning seat; 12, accommodating chamber; 13, air bag; 14, carrier plate; 15, reset member; 16, ball bearing; 17, guide member; 18, wire groove; 19, load sensor; 21, mounting frame; 22, counterweight component; 23, mounting plate; 24, circular track; 25, hanging wheel; 26, limit plate; 27, top plate; 28, telescopic member; T1, thickness measuring component 1; T2, thickness measuring component 2 ; 31. air pump; 32. shunt pipe; 33. air pressure sensor; 34. three-way valve; 41. lifting assembly; 42. rotary drive member; 51. operating table; 52. support plate; 53. mounting table; 151. counterweight; 152. pull rope; 153. air cylinder; 154. stopper; 155. ball head; 156. clamping member; 321. main pipe; 322. branch pipe 1; 323. branch pipe 2; 324. choke tube; 325. baffle; W. part to be tested; O1. axis 1; O2. axis 2. DETAILED DESCRIPTION

[0050] The present application is further described in detail below in conjunction with the accompanying drawings. It is necessary to point out here that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technical personnel in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0051] First embodiment

[0052] like Figure 1-5 As shown, a method for measuring and rejecting the eccentricity of porcelain parts and blanks of porcelain insulators is provided. The method is used to measure and reject disc-type suspension porcelain insulators. The porcelain parts or blanks of disc-type suspension porcelain insulators are applicable. The above-mentioned porcelain parts and blanks belong to the test piece W of the method. The method specifically comprises the following steps:

[0053] Step 1, place the workpiece W to be measured on the positioning mechanism 1. The inner diameter of the positioning mechanism 1 is slightly larger than the diameter of the outer wall of the workpiece W to be measured. The positioning mechanism 1 positions the workpiece W to be measured to a state where the axis of its outer wall is aligned with the measuring station, so that the axis of the outer wall of the workpiece W to be measured is coaxial with the axis of the positioning mechanism 1. The axis of the positioning mechanism 1 is the measuring station. The axis of the outer wall of the workpiece W to be measured is recorded as axis 1 O1, and the axis of the inner wall of the workpiece W to be measured is recorded as O2. The wall thickness of the workpiece W to be measured is measured by the thickness measuring mechanism 2. The thickness measuring mechanism 2 has two thickness measuring components, which are divided into thickness measuring component 1 T1 and thickness measuring component 2 T2. In the preparation stage of eccentricity measurement, the thickness measuring component 1 T1 of the thickness measuring mechanism 2 is placed inside the workpiece W to be measured, and the thickness measuring component 2 T2 of the thickness measuring mechanism 2 is placed outside the workpiece W to be measured.

[0054] The thickness measuring mechanism 2 can be a contact thickness measuring device, such as a vernier caliper; it can also be a non-contact thickness measuring device. In this embodiment, a non-contact thickness measuring device is used to measure the wall thickness of the workpiece W. Specifically, the non-contact thickness measuring device is preferably a laser thickness measuring device. In addition, in some other embodiments, an infrared thickness measuring device or an ultrasonic thickness measuring device can be used to replace the thickness measuring mechanism 2 in this embodiment.

[0055] Step 2: The thickness measuring mechanism 2 rotates around the axis of the positioning mechanism 1, that is, around the axis -O1, and measures the wall thickness N times at N rotation angles. The wall thickness is recorded as E. i , and according to the wall thickness E i Calculate the eccentricity d between the inner and outer centers of the test piece W. The eccentricity d is calculated by the following three equations:

[0056]

[0057] Where dE is the range of N wall thickness measurement results; max{E i} is the maximum wall thickness in N wall thickness measurements, is the minimum wall thickness in N wall thickness measurements, and k is the intermediate value. Figure 2 As shown, N is 6, and the wall thickness is measured at 6 locations. In addition, in some other embodiments, the wall thickness E can also be increased. i The number of measurements, for example Figure 3 The measurement process shown in the figure is a total of 8 measurements. Here the wall thickness E i The more measurements you make, the more accurate the calculation results will be.

[0058] In step 2, the thickness measuring mechanism 2 can also be controlled to remain stationary, and the ceramic piece or blank can be driven to rotate by rotating the positioning mechanism 1 to achieve the wall thickness E of the corresponding parts of the ceramic piece or blank at different angles. i measurement.

[0059] Step 3: For a certain type of porcelain insulator product produced by the manufacturer, the eccentricity of the test piece W is analyzed. When the eccentricity d of the test piece W exceeds the preset rejection threshold d MAX When d>d MAX When the test piece W is rejected, in order to obtain highly consistent products and meet the Westgard Sigma multi-rule of quality management, the rejection threshold is established as follows:

[0060]

[0061] Where s is the standard deviation of the two-dimensional normal distribution of the eccentricity d of a batch of porcelain parts or blanks calculated in advance. When the test piece W is a porcelain part, the standard deviation of the two-dimensional normal distribution is calculated using a batch of porcelain parts prepared in advance. When the test piece W is a blank, the standard deviation of the two-dimensional normal distribution is calculated using a batch of blanks prepared in advance. d is the average value of the eccentricity of this batch of porcelain parts or blanks, d MAX is the rejection threshold for each subsequent porcelain or blank inspection. P is the probability value obtained by querying the Westgard sigma multi-rule. For example, if there is a 3 sigma quality requirement for the product, the P value is 0.9973.

[0062] Second embodiment

[0063] This embodiment relates to a measuring system for implementing the above-mentioned eccentricity measurement and rejection method, the measuring system comprises a positioning mechanism 1 and a thickness measuring mechanism 2, such as Figure 4-9As shown, the positioning mechanism 1 is used to perform axial positioning on the workpiece W to be tested, so that the axis O1 of the workpiece W to be tested coincides with the axis center of the positioning mechanism 1. The thickness measuring mechanism 2 is used to collect the wall thickness data of the workpiece W to be tested at multiple angles. The thickness measuring mechanism 2 is connected to a control module, and the control module is used to calculate the eccentricity data based on the wall thickness data. The thickness measuring component of the positioning mechanism 1 is divided into a thickness measuring component 1 T1 and a thickness measuring component 2 T2. Both the thickness measuring component 1 T1 and the thickness measuring component 2 T2 are laser distance measuring devices, and a transmitting probe and a receiving probe are provided on the side of the laser distance measuring device. The heights of the transmitting probes of the two laser distance measuring devices are consistent, and the two transmitting probes are arranged opposite to each other.

[0064] The system also includes an air supply mechanism 3 and a driving mechanism 4 connected to the control module. The positioning mechanism 1 has a pneumatic actuator. The air supply mechanism 3 is used to make the pneumatic actuator locate the outer wall axis of the workpiece W to be measured. The driving mechanism 4 is used to place the two thickness measuring components T1 and T2 of the thickness measuring mechanism 2 inside and outside the workpiece W to be measured, respectively, and make the thickness measuring mechanism 2 rotate around the axis -O1.

[0065] The driving mechanism 4 includes a lifting assembly 41 and a rotating driving member 42 fixedly mounted at the output end of the lifting assembly 41. The thickness measuring mechanism 2 includes a mounting frame 21 fixedly mounted at the output end of the rotating driving member 42. The mounting frame 21 is F-shaped and has a horizontal bar and two vertical bars. One vertical bar is arranged in the middle of the lower side of the horizontal bar, and the other vertical bar is arranged at one end of the lower side of the horizontal bar. A rotating rod is fixedly mounted in the middle of the upper side of the horizontal bar, and the horizontal bar is fixedly connected to the output end of the rotating driving member 42 through the rotating rod. A thickness measuring component T1 of the thickness measuring mechanism 2 is arranged at the bottom of the middle vertical bar of the mounting frame 21, and another thickness measuring component T2 of the thickness measuring mechanism 2 is arranged at the bottom of the vertical bar at one end of the mounting frame 21. A counterweight component 22 is fixedly mounted at the other end of the lower side of the horizontal bar of the mounting frame 21 to balance the weight on both sides of the mounting frame 21.

[0066] In the preparation stage of eccentricity measurement, the workpiece W to be measured is first inserted into the positioning mechanism 1, and the positioning mechanism 1 performs axial positioning of the workpiece W to be measured through the pneumatic actuator, so that the axis line O1 of the workpiece W to be measured coincides with the axis center of the positioning mechanism 1, and the positioning of the workpiece W to be measured is completed. Then, the rotary drive member 42 and the mounting frame 21 are moved downward by the lifting assembly 41, so that the thickness measuring component T1 is inside the workpiece W to be measured, and the thickness measuring component T2 is outside the workpiece W to be measured, and the preparation stage of wall thickness measurement is completed. In this embodiment, the center of the thickness measuring component T1 is located on the axis line 1 of the workpiece W to be measured, and the rotating rod on the mounting frame 21 is coaxially arranged with the positioning mechanism 1.

[0067] In the formal stage of eccentricity measurement, the wall thickness E of the test piece W is measured at different angles. iDuring the measurement process, the rotating driving component 42 rotates the thickness measuring component T1 and the thickness measuring component T2 to different angles in sequence through the mounting frame 21. The thickness measuring component T1 and the thickness measuring component T2 cooperate with the control module to measure the wall thickness of different positions of the workpiece W to be measured. Specifically, the thickness measuring component T1 and the thickness measuring component T2 emit lasers to the workpiece W to be measured at the same angle, and respectively detect the distance 1 between the thickness measuring component T1 and the inner wall of the workpiece W to be measured, and the distance 2 between the thickness measuring component T2 and the outer wall of the workpiece W to be measured. The distance between the thickness measuring component T1 and the thickness measuring component T2 always remains unchanged, and this distance is recorded as the thickness measuring component spacing. The thickness measuring component spacing is first subtracted from the spacing 1 and then from the spacing 2, and the resulting value is the wall thickness E at this angle. i The above calculation process is realized by a control module. The control module calculates the eccentricity distance d and the rejection threshold d according to the eccentricity measurement and elimination method described in the first embodiment. MAX Calculation is performed to measure and remove the eccentricity of porcelain insulator parts or blanks.

[0068] It should be noted that in this embodiment, the two thickness measuring components T1 and T2 of the thickness measuring mechanism 2 are driven to rotate at different heights by the lifting assembly 41 in cooperation with the rotating driving member 42. The eccentricity between the outer wall circle and the inner hole circle of the test piece W at different heights can be measured. During the entire measurement process, the thickness measuring mechanism 2 performs eccentricity measurement on the test piece W at different heights from top to bottom. After the eccentricity measurement of the previous height is passed, the eccentricity measurement of the next height is performed. If the eccentricity d of a certain height exceeds the rejection threshold d MAX When the eccentricity measurement of the tested piece W fails, the product is deemed unqualified. At this time, the control module generates an alarm and stops the measurement, and the operator scraps the product, effectively preventing the eccentric product from flowing into the next process. MAX The eccentricity error of the qualified porcelain insulator product can be controlled within the range of 0 to 1 mm.

[0069] In some other embodiments, when an infrared thickness measuring device is used to replace the thickness measuring mechanism 2 in this embodiment, the thickness measuring components T1 and T2 are replaced by infrared probes, and the wall thickness E can be calculated according to the infrared distance measurement principle. i When an ultrasonic thickness measuring device is used to replace the thickness measuring mechanism 2 in this embodiment, the thickness measuring components T1 and T2 are replaced by ultrasonic probes, and the wall thickness E is calculated by the propagation speed and time of ultrasonic waves in the medium. i The above alternatives can automatically compare whether the wall thickness of the product is within the standard requirements, solving the problem that the traditional measurement method cannot accurately measure the wall thickness. When using ultrasonic thickness measuring equipment, it is also possible to perform flaw detection on the blanks and porcelain parts, effectively preventing defective products from flowing into the next process and causing quality problems.

[0070] In order to prevent the test piece W from being damaged during the detection process and to improve the measurement accuracy, the positioning mechanism 1 fixes the test piece W to the axis of the positioning mechanism 1 through a pneumatic actuator. For the specific positioning process, please refer to Figure 7-9 . The positioning mechanism 1 includes a positioning seat 11 with an opening at the top, a accommodating chamber 12 arranged inside the positioning seat 11, an airbag 13 fixedly arranged at the upper part of the accommodating chamber 12, and a movable carrier 14 arranged at the lower part of the accommodating chamber 12, and the carrier 14 can slide along any horizontal direction on the bottom wall of the positioning seat 11. The airbag 13 is annular as a whole and has a built-in annular cavity. The axis of the positioning mechanism 1 is the axis of the positioning seat 11. The accommodating chamber 12 includes an upper cavity and a lower cavity, and the inner diameter of the lower cavity is larger than that of the upper cavity. The carrier 14 is located in the lower cavity, and the airbag 13 is located in the upper cavity. The airbag 13 is the pneumatic actuator of the positioning mechanism 1.

[0071] During positioning, the piece to be tested W is inserted into the positioning seat 11, and the airbag 13 is sleeved on the outside of the piece to be tested W. The piece to be tested W is placed on a movable carrier 14, and balls 16 are evenly arranged along the circumference at the bottom of the carrier 14, resulting in a smaller friction between it and the positioning seat 11. When the airbag 13 is inflated, if the piece to be tested W is not at the axis of the positioning seat 11, the airbag 13 can push the piece to be tested W to the center of the positioning seat 11. Avoid the decrease in measurement accuracy due to deviations in the placement positions of different pieces to be tested W. The piece to be tested W is positioned by the airbag 13, the force-bearing area of ​​the outer wall of the piece to be tested W is increased, and the impact force received by the piece to be tested W during positioning is reduced. And because the inner wall aperture of the piece to be tested W is small, after it is accurately positioned, it can also avoid the inner wall from contacting the thickness measuring mechanism 2 during the measurement process. Provide full protection for the inner and outer walls of the insulator. In addition, in some other embodiments, the positioning mechanism 1 may also be merely a cylindrical base with an upper opening, and the inner diameter of the base is slightly larger than the outer wall diameter of the porcelain piece or blank.

[0072] Furthermore, after multiple eccentricity measurements, if a reset structure is not provided, the carrier plate 14 may move to the inner wall of the positioning seat 11, causing the carrier plate 14 to be unable to move afterwards. At this time, there is a large friction between the workpiece W to be tested and the carrier plate 14, and the positioning accuracy of the airbag 13 to the workpiece W to be tested may be affected. Therefore, a reset member 15 is also provided on the positioning mechanism 1 to reset the carrier plate 14 to the axis of the positioning mechanism 1 after the wall thickness measurement of each workpiece W to be tested is completed. After reset, the axis of the carrier plate 14 coincides with or is close to the axis of the positioning mechanism 1.

[0073] Specifically, the reset member 15 includes a counterweight 151 located directly below the positioning seat 11, and a pull rope 152 provided between the counterweight 151 and the carrier plate 14. When positioning the workpiece W to be tested, the air supply mechanism 3 drives the counterweight 151 to move upward, so that the pull rope 152 remains loose. At this time, the carrier plate 14 is in a non-constrained state. After the wall thickness measurement of the workpiece W to be tested is completed, the counterweight 151 is reset, and the pull rope 152 is pulled downward to reset the carrier plate 14. In this embodiment, the counterweight 151 is driven to move by the air supply mechanism 3. A guide member 17 is formed in the center of the bottom wall of the positioning seat 11, and a wire groove 18 corresponding to the pull rope 152 is provided through the guide member 17, and the wire groove 18 passes through the bottom wall of the positioning seat 11. The inner wall of the guide member 17 is in a trumpet shape, and the guide member 17 protrudes upward, which can avoid stress concentration between the pull rope 152 and the positioning seat 11 during resetting, and ensure that when the pull rope 152 pulls the carrier plate 14, the upper part of the pull rope 152 is close to a horizontal state, thereby improving the resetting pulling effect on the carrier plate 14 and reducing the wear of the pull rope 152 and the weight of the counterweight 151.

[0074] The system also includes a bracket 5, which includes an operating table 51 and a support plate 52 arranged below the top wall of the operating table 51. A load sensor 19 is fixedly arranged between the operating table 51 and the positioning seat 11. A limit rod is fixedly arranged at the bottom of the positioning seat 11. The limit rod is embedded in the operating table 51. The positioning seat 11 is limited by the limit rod to improve the detection accuracy of the load sensor 19. An air cylinder 153 is fixedly arranged on the support plate 52, and a counterweight 151 is slidably arranged on the outside of the air cylinder 153. The counterweight 151 is a cylinder with a built-in counterweight block. The air supply mechanism 3 includes an air pump 31, a shunt pipe 32 connected to the air outlet of the air pump 31, and an air pressure sensor 33 and a three-way valve 34 arranged on the shunt pipe 32. The air bag 13 and the air cylinder 153 are both connected to the shunt pipe 32. The bracket 5 also includes a mounting platform 53 fixed on the top wall of the operating table 51, the lifting assembly 41 is fixed on the mounting platform 53, the rotating rod on the mounting frame 21 passes through the mounting platform 53, the lifting assembly 41 is preferably a screw motor, and the rotating drive member 42 is preferably a motor, and the rotating drive member 42 is fixedly arranged on a support frame, and the support frame is threadedly connected to the output shaft of the lifting assembly 41. In addition, in some other embodiments, the lifting assembly 41 and the rotating drive member 42 can also be replaced by other existing linear drive structures and rotary drive structures.

[0075] The shunt pipe 32 includes a main pipe 321, a branch pipe 1 322 and a branch pipe 2 323. The main pipe 321 is fixedly arranged at the air outlet of the air pump 31. The air outlet of the main pipe 321 is provided with a three-way joint. The air inlets of the branch pipe 1 322 and the branch pipe 2 323 are connected to the main pipe 321 through the three-way joint, and the air outlets of the branch pipe 1 322 and the branch pipe 2 323 are connected to the air cylinder 153 and the air bag 13 respectively. The air pressure sensor 33 and the three-way valve 34 are both arranged on the main pipe 321. The upper and lower ports of the three-way valve 34 are fixedly arranged on the main pipe 321, and the port on the side of the three-way valve 34 is connected to the external atmosphere of the air supply mechanism 3. The control module is composed of a controller 1, a controller 2 and a PC end. The controller 1 is connected to an alarm. When the product is unqualified, the controller 2 sends an alarm through the alarm to remind the operator that the unqualified product needs to be scrapped and discarded. The controller 1 is preferably a PLC controller, which is electrically connected to the PC end and is used to calculate the wall thickness E i and the rejection threshold d MAX , and sends its calculation results to the PC for the operator to view. Controller 2 is preferably a single-chip microcomputer controller, which is arranged on a mounting frame 21 and is wirelessly connected to the PLC controller. In addition, in some other embodiments, the single-chip microcomputer controller can also be electrically connected to the PLC controller through an electric slip ring, and the PLC controller can also be connected to the PC through a wireless signal. The lifting assembly 41 and the rotating drive member 42 of the driving mechanism 4, the load sensor 19 of the positioning mechanism 1, and the air pump 31, the air pressure sensor 33 and the three-way valve 34 of the air supply mechanism 3 are all electrically connected to the controller one, and the two thickness measuring components T1 and T2 of the thickness measuring mechanism 2 are all electrically connected to the controller two.

[0076] After the reset member 15 is set, during the specific positioning process, the load sensor 19 cooperates with the control module to detect whether the test piece W is placed on the carrier 14. When the test piece W is placed on the carrier 14, the pressure on the load sensor 19 exceeds the set value, indicating that the test piece W is placed on the carrier 14, and the system automatically performs positioning of the test piece W, eccentricity measurement, and calculation of the rejection threshold.

[0077] During positioning, the air pump 31 inflates the airbag 13 and the air cylinder 153 through the shunt pipe 32, so that the airbag 13 expands and the counterweight 151 moves upward, ensuring that the movement of the carrier plate 14 is not affected by the tension of the pull rope 152. In addition, during the eccentricity measurement process, the air pressure in the shunt pipe 32 is measured by the air pressure sensor 33 in cooperation with the control module, and the air pump 31 is adjusted by the control module to ensure that during the eccentricity measurement process, after the air pressure in the shunt pipe 32 is stable, that is, after the air pump 31 is started for a period of time, the air pressure in the main pipe 321 is within the set range. After the eccentricity calculation is completed, the air pump 31 is turned off, and the upper port of the three-way valve 34 is connected to the side port. At this time, the gas in the airbag 13 and the air cylinder 153 can be discharged outward through the shunt pipe 32 and the three-way valve 34, and the counterweight 151 resets the carrier plate 14 by its own weight. In addition, if the air pump 31 adopts a bidirectional pump, such as a Roots pump, the three-way valve 34 can be eliminated, and the bidirectional pump can be used to supply and exhaust air to the shunt pipe 32.

[0078] For porcelain insulators with larger sizes, the reset member 15 needs to be equipped with a heavier counterweight 151, which may cause excessive energy consumption of the air supply mechanism 3. Figure 7-10 In view of this situation, a clamping component 156 is also fixedly provided under the top wall of the operating table 51. The clamping component 156 is preferably a magnet, and the shape of the magnet is preferably annular. Accordingly, the whole or part of the material of the counterweight 151 is made of ferromagnetic metal. When positioning the test piece W, the air supply mechanism 3 is used to inflate the air cylinder 153, and the counterweight 151 is moved up to a state in which it fits with the magnet. When the counterweight 151 fits with the magnet, the sum of the magnetic force of the magnet and the thrust provided by the air supply mechanism 3 to the counterweight 151 is not less than the deadweight of the counterweight 151. After the measurement is completed, after the gas in the air cylinder 153 is discharged from the three-way valve 34, the deadweight of the counterweight 151 is greater than the magnetic force of the magnet. Under the action of gravity, the counterweight 151 is reset, and its reset effect on the carrier 14 is exerted. In addition, in some other embodiments, the clamping component 156 can also be a sleeve, and the counterweight 151 is embedded in the sleeve after moving up, and the sum of the friction between the sleeve and the counterweight 151 and the thrust provided by the air supply mechanism 3 to the counterweight 151 is not less than the weight of the counterweight 151, and the weight of the counterweight 151 is greater than the friction between the sleeve and the counterweight 151.

[0079] On the basis of providing the clamping component 156 , a flow blocker is also provided on the second branch pipe 233 . The flow blocker includes a flow blocker tube 324 provided on the second branch pipe 323 . Figure 5 and Figure 6The choke tube 324 is not shown in the figure. When the size of the test piece W is small, or the pressure bearing capacity of the test piece W and the material of the air bag 13 is strong, the choke may not be set. The choke tube 324 is fixed between the branch pipe 2 323 and the main pipe 321, and the choke also includes a plurality of baffles 325 arranged inside the choke tube 324 and staggered with each other. In addition, in other embodiments, a plurality of baffles may be arranged inside the choke tube 324, and adjacent baffles may have staggered through holes. During the positioning process, the gas entering the branch pipe 2 323 is intercepted by the choke tube 324 in cooperation with the baffle 325, so as to reduce the rate of change of the air pressure in the air bag 13. After a period of time after the air pump 31 supplies air, the counterweight 151 is connected to the clamping component 156. At this time, the air pump 31 reduces the power, and cooperates with the air pressure sensor 33 and the controller to stabilize the air pressure in the main pipe 321 within the set range. In this process, excessive air pressure in the branch pipe 323 and the airbag 13 is avoided, so as to protect the test piece W and the airbag 13.

[0080] In addition, a stopper 154 is fixedly provided on the outer wall of the gas cylinder 153. The stopper 154 is used to support the counterweight 151 after the gas in the gas cylinder 153 is discharged, so as to prevent the pull rope 152 from being kept in a tensioned state for a long time in a non-working state. The stopper 154 is preferably a convex ring fixedly provided on the outer wall of the gas cylinder 153, and an elastic buffer layer is provided on the upper surface of the convex ring. In the case of setting the stopper 154, although the carrier plate 14 cannot be accurately reset to the axis of the positioning seat 11, the axis of the carrier plate 14 is near the axis of the positioning seat 11, so that the outer wall of the carrier plate 14 and the inner wall of the positioning seat 11 have a sufficient distance. During the positioning process, the carrier plate 14 has a sufficient movable distance. The decrease in the reset accuracy does not affect the positioning accuracy, and can extend the service life of the reset member 15. Ball heads 155 are provided at both ends of the pull rope 152. The two ball heads 155 are rotatably connected to the bottom of the carrier plate 14 and the top of the counterweight 151 respectively, so as to reduce the wear of the ends of the pull rope 152.

[0081] In addition, in some other embodiments, a suspension assembly is further provided on the thickness measuring mechanism 2. The suspension assembly includes a mounting plate 23, an annular track 24 fixed to the bottom of the mounting plate 23, two suspension wheels 25 symmetrically arranged on the inner side of the annular track 24, two limit plates 26 respectively fixed to the two sides of the top of the mounting plate 23, and a top plate 27 fixed to the top of the limit plates 26, the two suspension wheels 25 are respectively connected to the two ends of the cross bar of the mounting frame 21, the mounting plate 23 is hinged to the rotating rod on the mounting frame 21, an elastic buffer layer is provided on the lower surface of the top plate 27, and the limit plates 26 penetrate the top wall of the mounting platform 53.

[0082] When the lifting assembly 41 moves the thickness measuring component T1 downward to the inside of the workpiece W to be measured, the elastic buffer layer on the lower surface of the top plate 27 is in close contact with the top wall of the mounting platform 53, and the mounting frame 21 can be suspended under the annular track 24 through the hanging wheel 25, and the annular track 24 is suspended on the mounting platform 53 through the limit plate 26 and the top plate 27. In the process of measuring the wall thickness, the deformation of the mounting frame 21 caused by gravity can be reduced. After the measurement is completed, the thickness measuring component T1 can also be placed in this position, and the mounting frame 21 of the thickness measuring mechanism 2 can be suspended and supported by the suspension assembly to avoid the decrease in the accuracy of the thickness measuring mechanism 2 after long-term use. In addition, a pair of telescopic parts 28 can be set on the mounting platform 53, and the telescopic parts 28 are preferably electromagnets. A group of jacks corresponding to the telescopic parts 28 are opened on the limit plate 26. The workpiece W to be measured can be eccentrically measured at different heights, and the telescopic parts 28 can be inserted into the corresponding jacks at different measuring heights to achieve the suspension support of the thickness measuring mechanism 2 at different measuring heights.

[0083] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A method for measuring and removing the eccentricity of porcelain insulator porcelain parts and blanks, characterized in that: The porcelain insulator porcelain piece and the blank are both the test pieces of the method, and the method comprises the following steps: Step 1: Position the piece to be tested; Step 2: Measure the wall thickness of the test piece at different angles, and calculate the eccentricity of the test piece based on the wall thickness. The calculation method of the eccentricity is as follows: d=dE / (2k) Where dE is the range of N wall thickness measurement results; max{E i } is the maximum wall thickness in N wall thickness measurements, is the minimum wall thickness in N wall thickness measurements, k is the middle value, and d is the eccentricity; Step 3: Analyze the eccentricity of the test piece. When the eccentricity of the test piece exceeds the preset rejection threshold, the test piece is rejected. The method for establishing the rejection threshold is as follows: Among them, d MAX is the rejection threshold of the tested part, s is the standard deviation of the two-dimensional normal distribution, and P is the probability value obtained by querying the Westgard sigma multi-rule.

2. The method for measuring and removing eccentricity of porcelain insulator parts and blanks according to claim 1 is characterized in that: In step 3, the standard deviation of the two-dimensional normal distribution is calculated as follows: in, It is the average value of the eccentricity of a batch of porcelain parts or blanks calculated in advance.

3. A measurement system for implementing the method according to claim 1 or 2, characterized in that: The system includes a positioning mechanism, a thickness measuring mechanism and a control module. The positioning mechanism is used to perform axial positioning on the workpiece to be tested. The thickness measuring mechanism is used to collect wall thickness data of the workpiece to be tested at different angles and send the wall thickness data to the control module. After receiving the wall thickness data, the control module obtains the eccentricity of the workpiece to be tested according to the eccentricity calculation method, and determines whether the workpiece to be tested needs to be rejected based on the rejection threshold.

4. The measuring system according to claim 3, characterized in that: The system also includes an air supply mechanism and a driving mechanism connected to the control module. The positioning mechanism has a pneumatic actuator, and the air supply mechanism is used to enable the pneumatic actuator to locate the outer wall axis of the workpiece to be measured. The thickness measuring mechanism has two thickness measuring components. The driving mechanism is used to place the two thickness measuring components of the thickness measuring mechanism inside and outside the workpiece to be measured, respectively, and to enable the thickness measuring mechanism and the positioning mechanism to rotate relative to each other about the outer wall axis of the workpiece to be measured.

5. The measuring system according to claim 4, characterized in that: The positioning mechanism includes a positioning seat, a receiving cavity arranged inside the positioning seat, an airbag fixed to the upper part of the receiving cavity, and a carrier plate arranged at the lower part of the receiving cavity, wherein the carrier plate can slide along any horizontal direction on the bottom wall of the positioning seat.

6. The measuring system according to claim 5, characterized in that: The positioning mechanism also includes a reset member, which is used to reset the carrier plate to the axis center of the positioning mechanism after the wall thickness measurement of each piece to be measured is completed.

7. The measuring system according to claim 4, characterized in that: The reset member includes a counterweight member located directly below the positioning seat, and a pull rope provided between the counterweight member and the carrier plate. When positioning the workpiece to be measured, the counterweight member moves upward to keep the pull rope loose and the carrier plate in an unconstrained state; after the wall thickness measurement of the workpiece to be measured is completed, the counterweight member moves downward to reset and constrain the carrier plate through the pull rope.

8. The measuring system according to claim 7, characterized in that: The bottom of the carrier plate is evenly provided with balls along the circumferential direction, the center of the bottom wall of the positioning seat protrudes upward to form a guide piece, and a wire groove corresponding to the pull rope is penetrated in the guide piece, and the wire groove penetrates the bottom wall of the positioning seat.

9. The measuring system according to claim 7, characterized in that: The system also includes a bracket, a load sensor is fixedly provided between the bracket and the positioning seat, and an air cylinder is fixedly provided on the bracket, and the air cylinder is slidably provided under the counterweight. The air supply mechanism includes an air pump, a shunt pipe connected to the air outlet of the air pump, and an air pressure sensor and a three-way valve arranged on the shunt pipe. The airbag and the air cylinder are both connected to the shunt pipe. A clamping component corresponding to the counterweight is provided on the bracket, and a flow blocking component is provided on the branch connecting the shunt pipe and the airbag.

10. The measuring system according to claim 4, characterized in that: The driving mechanism includes a lifting component and a rotating driving member fixedly arranged at the output end of the lifting component, the thickness measuring mechanism includes a mounting frame fixedly arranged at the output end of the rotating driving member, a thickness measuring component of the thickness measuring mechanism is arranged in the middle of the mounting frame, and another thickness measuring component of the thickness measuring mechanism is arranged at one end of the mounting frame, and a counterweight component is arranged at the other end of the mounting frame.

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