Stator diameter measuring device and stator diameter measuring method

Abstract

The present invention provides a stator diameter measuring device that can improve the production efficiency of a stator production line and can adjust the welding process at the appropriate time. It has a position measuring unit that measures the position of the welding portion and the welding portion projection range; a temperature measuring unit that measures the actual body temperature of the stator body; a time measuring unit that measures the welding elapsed time; a diameter calculating unit that calculates the actual outer diameter and the actual inner diameter of the stator body under the welding elapsed time; a estimated temperature calculating unit that calculates the estimated temperature based on an estimated temperature database; an estimated change amount calculating unit that calculates the estimated change amount based on an estimated change amount database; and a diameter estimating unit that calculates the estimated outer diameter and the estimated inner diameter of the stator body under the reference body temperature according to the actual outer diameter and the actual inner diameter and the calculated estimated change amount.

Description

Technical Field

[0001] This invention relates to a stator diameter measuring device and a stator diameter measuring method. Background Technology

[0002] A known method for manufacturing a component for a rotary electric machine involves welding a motor core, which consists of multiple stacked electromagnetic steel plates, from one axial end to the other. For example, International Publication No. 2018 / 164277 discloses a method for manufacturing a component for a rotary electric machine, comprising: a step of stacking multiple electromagnetic steel plates to form a motor core; and a welding step in which the motor core is welded along the stacking direction under a pressure less than that required to bring the electromagnetic steel plates together, so that the thickness in the stacking direction, from one end of the motor core to the other end, remains unchanged.

[0003] In the manufacturing method of a component for a rotating electrical machine disclosed in International Publication No. 2018 / 164277, the motor core is welded while being pressurized along the stacking direction to the extent that a gap is created between the stacked electromagnet plates of the motor core. After welding, the gap between the electromagnet plates can shrink in the axial direction (the direction in which adjacent electromagnet plates approach each other). Therefore, when the motor core cools from a state where the temperature has risen due to welding to a state of room temperature, the spacing between the stacked steel plates narrows along with the shrinkage of the welded portion. Since the shrinkage of the welded portion of the motor core is not hindered by the contact between the stacked steel plates, the tensile stress generated in the shrinking welded portion can be reduced.

[0004] On the other hand, because the motor core is welded into a linear fashion at specified intervals along its circumference, variations in the welding process lead to different amounts of shrinkage during cooling. Furthermore, the amount of shrinkage during cooling differs between the welded and unwelded portions of the motor core. Therefore, the outer and inner diameters of the motor core at room temperature differ before and after welding. Thus, it is essential to check whether the outer and inner diameters of the motor core after the welding process fall within specified ranges. Summary of the Invention

[0005] In the stator production line implementing this method for manufacturing components for rotating electric machines, the stator body (motor core) welded in the welding process is naturally cooled to a standard state, for example, 23 degrees Celsius, for 2 to 3 hours. Then, in the inspection process, the outer and inner diameters of the cooled stator body are measured using a three-dimensional measuring instrument. Thus, during the period when the welded stator body is cooled to its standard state, no processing is performed on the stator body, causing it to remain stationary, thereby reducing production efficiency.

[0006] Furthermore, in the stator production line, when adjustments to the welding process are needed based on the measurement results of the stator body during the inspection process, other stator bodies are welded in their pre-adjustment state during the period from when the stator body is welded in the welding process until it is cooled and measured in the inspection process. That is, in the aforementioned stator production line, because the stator body is held in place for cooling, a discrepancy arises between the time when the welding process adjustment is needed and the time when the adjustment is actually performed.

[0007] The purpose of this invention is to provide a stator diameter measuring device that can improve the production efficiency of a stator production line and can adjust the welding process at appropriate times.

[0008] An embodiment of the present invention provides a stator diameter measuring device for measuring the diameter of a stator body having multiple steel plates, wherein the multiple steel plates are stacked in a thickness direction and their outer peripheral sides are welded along the thickness direction. The stator diameter measuring device includes: a position measuring unit that measures the position of the measuring part relative to a reference position, using at least one of the welded portions of the multiple steel plates and the inner peripheral surface of the stator body overlapping the welded portions when viewed radially from the stator body; a temperature measuring unit that measures the actual body temperature of the stator body when the position measuring unit measures the position of the measuring part; a time measuring unit that measures the welding elapsed time, which is the elapsed time from the measurement start time, which is the time elapsed after a predetermined time since the completion of welding of the stator body; an acquisition unit that acquires the welding elapsed time measured by the time measuring unit, the actual body temperature measured by the temperature measuring unit, and the position of the measuring part relative to the reference position measured by the position measuring unit; and a diameter calculation unit that uses the position of the measuring part relative to the reference position to calculate the actual outer diameter of the stator body at the welding elapsed time. The system includes: at least one of the actual outer diameter and the actual inner diameter; a predicted temperature calculation unit having a predicted temperature database showing the relationship between the actual body temperature at the welding elapsed time and the predicted temperature of the stator body at the measurement start time, the predicted temperature calculation unit calculating the predicted temperature based on the predicted temperature database, according to the welding elapsed time and the actual body temperature; a predicted change calculation unit having a predicted change database showing the relationship between the welding elapsed time and the predicted change of the outer diameter and the inner diameter of the stator body for each predicted temperature, the predicted change calculation unit calculating the predicted change based on the predicted change database, according to the calculated predicted temperature and the welding elapsed time; and a diameter prediction unit calculating at least one of the predicted outer diameter and the predicted inner diameter of the stator body at a reference body temperature based on at least one of the calculated actual outer diameter and the actual inner diameter and the calculated predicted change.

[0009] According to one embodiment of the present invention, the stator diameter measuring device can improve the production efficiency of the stator production line and can adjust the welding process at appropriate times.

[0010] The above and other features, elements, steps, characteristics and advantages of the present invention can be more clearly understood from the following detailed description of preferred embodiments of the present invention, with reference to the accompanying drawings. Attached Figure Description

[0011] Figure 1 A three-dimensional view of the stator body is shown.

[0012] Figure 2 This shows a top view taken from the axial direction of the stator body.

[0013] Figure 3 A flowchart is shown for a stator production line incorporating a stator diameter measuring device according to an embodiment of the present invention.

[0014] Figure 4 This is a block diagram illustrating the control structure of a stator diameter measuring device according to an embodiment of the present invention.

[0015] Figure 5 A top view of a stator diameter measuring device according to an embodiment of the present invention is shown.

[0016] Figure 6 This is a side view illustrating the operation of the stator diameter measuring device according to an embodiment of the present invention.

[0017] Figure 7 This is a graph showing the relationship between the welding time and the actual body temperature of the stator diameter measuring device according to an embodiment of the present invention.

[0018] Figure 8 This is a graph showing the relationship between the actual body temperature and the estimated temperature of the stator diameter measuring device according to an embodiment of the present invention.

[0019] Figure 9 This is a graph showing the relationship between the welding time and the estimated change in the stator diameter measuring device according to an embodiment of the present invention.

[0020] Figure 10 A flowchart illustrating the inspection process of the stator diameter measuring device according to Embodiment 1 of the present invention is shown.

[0021] Figure 11 This is a coarse cross-sectional view showing the measuring surface of the stator diameter measuring device according to an embodiment of the present invention.

[0022] Figure 12 This is a schematic diagram showing the actual outer diameter and actual inner diameter of the stator diameter measuring device according to an embodiment of the present invention.

[0023] Figure 13 A flowchart illustrating the inspection process of the stator diameter measuring device according to Embodiment 2 of the present invention is shown.

[0024] (Symbol Explanation)

[0025] 1. Stator diameter measuring device

[0026] 2 Position Measurement Unit

[0027] 3 abutments

[0028] 4 mounting platforms

[0029] 5. Displacement sensor for outer diameter

[0030] 6 Outer diameter drive device

[0031] 7. Displacement sensor for inner diameter

[0032] 8. Drive device for inner diameter

[0033] 9 Temperature Measurement Section

[0034] 10 thermometers

[0035] 11 Time Measurement Department

[0036] 12 Acquisition Department

[0037] 13 Diameter Measurement Section

[0038] 14. Predicted Temperature Calculation Department

[0039] 15. Calculation Department for Estimated Changes

[0040] 16-diameter estimation section

[0041] 17Printing Department

[0042] 18 control devices

[0043] 19 Confirmation Measurement Department Detailed Implementation

[0044] Exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Furthermore, the same or equivalent parts in the drawings will be labeled with the same reference numerals without repeating their descriptions. Also, the dimensions of the constituent parts in the drawings do not faithfully represent the actual dimensions of the constituent parts or the dimensional ratios of each constituent part.

[0045] Furthermore, in the following description of the stator diameter measuring device 1 as an exemplary embodiment of the present invention, the direction parallel to the axis P of the stator body 100 is referred to as the "axial direction," the direction orthogonal to the axis P is referred to as the "radial direction," and the direction along the arc centered on the axis P is referred to as the "circumferential direction." Additionally, the vertical direction in which the stator diameter measuring device 1 is installed is defined as the "up-down direction." However, this definition of direction does not limit the orientation of the stator diameter measuring device 1 during use.

[0046] Furthermore, in the following explanation, the terms "fixed," "connected," "joined," and "installed" (hereinafter referred to as "fixed, etc.") include not only cases where parts are directly fixed to each other, but also cases where they are fixed via other parts. That is, in the following explanation, "fixed, etc." means both direct and indirect fixing of parts to each other.

[0047] Furthermore, in the following description of the stator diameter measuring device 1, the stator body 100 refers to the frame of the motor constructed by stacking electromagnetic steel sheets along the thickness direction. The stator body 100 has a through hole 105 for accommodating the rotor (see reference). Figure 1 The stator body 100 is a cylindrical shape extending along the axial direction.

[0048] (Structure of stator body 100)

[0049] use Figure 1 and Figure 2 The stator measured by the stator diameter measuring device 1 will be described. Figure 1 This is a three-dimensional view of the stator body 100. Figure 2 This is a top view taken along the axial direction of the stator body 100.

[0050] like Figure 1 and Figure 2 As shown, the stator body 100 is composed of multiple annular electromagnetic steel plates formed in a predetermined shape and stacked along the thickness direction. The stacked electromagnetic steel plates are welded together at multiple locations on the outer peripheral surface 104 along the plate thickness direction. The stator body 100 has a cylindrical yoke 101, multiple teeth 102 extending radially inward from the cylindrical yoke 101, and multiple flanges 103 extending radially outward from the cylindrical yoke 101. The front ends of the multiple teeth 102 form the inner peripheral surface of the through hole 105.

[0051] In this embodiment, the outer diameter of the stator body 100 refers to the diameter of the outer peripheral surface 104 of the magnetic yoke 101 on a plane orthogonal to the axis P at any position in the axial direction. The inner diameter of the stator body 100 refers to the diameter of the inner peripheral surface of the through hole 105 on a plane orthogonal to the axis P at any position in the axial direction. The stator body 100 has a plurality of linear welded portions 106 extending along the thickness direction on the outer peripheral surface 104 of the cylindrical magnetic yoke 101. The welded portions 106 are located within the entire stacked electromagnetic steel plates. That is, the welded portions 106 have a shape that extends linearly from one end of the stator body 100 to the other end in the axial direction. In this embodiment, the stator body 100 has eight linear welded portions 106.

[0052] (Implementation Method 1)

[0053] Next, use Figures 3 to 9 Embodiment 1 of an example of the stator diameter measuring device 1 of the present invention will be described. Figure 3 This is a flowchart of a stator production line L that includes a stator diameter measuring device 1. Figure 4 This is a block diagram showing the control structure of the stator diameter measuring device 1. Figure 5 This is a top view of the stator diameter measuring device 1. Figure 6 This is a side view showing the operation of the stator diameter measuring device 1.

[0054] Figure 7 It is a graph showing the relationship between the welding elapsed time T1 of the stator diameter measuring device 1 and the actual body temperature tr. Figure 8 It is a graph showing the relationship between the actual body temperature tr and the estimated temperature te of the stator diameter measuring device 1. Figure 9 It is a graph showing the relationship between the welding elapsed time T1 of the stator diameter measuring device 1 and the estimated change Ce.

[0055] like Figure 3 As shown, the stator production line L, including the stator diameter measuring device 1, is a production line for producing stator bodies from electromagnetic steel sheets. The stator production line L includes a stamping device 200, a welding device 300, and the stator diameter measuring device 1. The stamping device 200 is a device for punching and stacking electromagnetic steel sheets. The welding device 300 is a device for welding the electromagnetic steel sheets stacked by the stamping device 200. The stator diameter measuring device 1 is a device for measuring the outer diameter (actual outer diameter D1r) and inner diameter (actual inner diameter D2r) of the electromagnetic steel sheets welded by the welding device 300. The stator production line L consists of the stamping device 200, the welding device 300, and the stator diameter measuring device 1 sequentially from upstream.

[0056] (Structure of stator diameter measuring device 1)

[0057] like Figure 3 and Figure 4 As shown, the stator diameter measuring device 1 is a device for measuring the actual outer diameter D1r and the actual inner diameter D2r of the stator body 100. The stator body 100 has multiple electromagnetic steel plates (see reference) welded to its outer periphery along the thickness direction in a stacked state along the thickness direction. Figure 2 The stator diameter measuring device 1 acquires the stator body 100 welded by the welding device 300 via a conveying device (not shown). After measuring the actual outer diameter D1r and actual inner diameter D2r of the acquired stator body 100, the stator diameter measuring device 1 removes the stator body 100 via the conveying device (not shown). The stator diameter measuring device 1 includes a position measuring unit 2, a temperature measuring unit 9, a time measuring unit 11, an acquisition unit 12, a diameter calculation unit 13, a predicted temperature calculation unit 14, a predicted change calculation unit 15, a diameter prediction unit 16, a printing unit 17, and a control device 18.

[0058] like Figures 4 to 6As shown, the position measuring unit 2 uses at least one of the welded portions 106 of the plurality of electromagnetic steel plates and the inner peripheral surface of the through hole 105 of the stator body 100 that overlaps with the plurality of welded portions 106 when the stator body 100 is viewed radially as a measuring point, and measures the position of the measuring point relative to the reference position P0. The reference position P0 is defined as the origin of the orthogonal coordinates of a plane (measuring surface) orthogonal to the axial direction of the stator body 100 placed on the mounting table 4. In this embodiment, the reference position P0 is the axial position of the stator body 100 (refer to...). Figure 5 The position measuring unit 2 includes a base 3, a mounting platform 4, multiple outer diameter displacement sensors 5, an outer diameter drive device 6, multiple inner diameter displacement sensors 7, an inner diameter drive device 8, and a control device 18.

[0059] like Figure 5 and Figure 6 As shown, the mounting platform 4 is a platform for positioning the stator body 100 relative to the stator diameter measuring device 1. The mounting platform 4 is set on the base 3 of the stator diameter measuring device 1. On the mounting platform 4, the welded stator body 100 is placed on the mounting platform 4 with its axis P facing upwards and downwards via a conveying device (not shown). The mounting platform 4 positions the stator body 100 relative to any reference position P0 in the stator diameter measuring device 1.

[0060] Multiple outer diameter displacement sensors 5 are sensors that measure the measurement points of welded portions 6 in the stator body 100. Multiple outer diameter displacement sensors 5 are sensors that measure the amount of displacement from a reference value. In this embodiment, the outer diameter displacement sensors 5 are contact displacement sensors. Multiple outer diameter displacement sensors 5 are supported by an outer diameter drive device 6 so that they can move in the vertical direction. Multiple outer diameter displacement sensors 5 are located on a plane orthogonal to the axis P of the stator body 100 mounted on the mounting platform 4, and on an annulus centered on the axis P of the stator body 100. Furthermore, multiple outer diameter displacement sensors 5 are respectively located radially outside each welded portion 106 in the stator body 100. Thus, multiple outer diameter displacement sensors 5 move simultaneously in the same direction by the same amount along the welded portion 106 of the stator body 100 mounted on the mounting platform 4. Multiple outer diameter displacement sensors 5 are connected to a control device 18. The coordinate positions of each of the multiple outer diameter displacement sensors 5 are pre-calculated with the reference position P0 as the origin.

[0061] The outer diameter drive unit 6 is a drive device capable of linearly moving multiple outer diameter displacement sensors 5 in the vertical direction. The outer diameter drive unit 6 supports multiple outer diameter displacement sensors 5 from a frame (not shown) above the stator body 100, which is mounted on the mounting platform 4. The outer diameter drive unit 6 is connected to the control device 18. The outer diameter drive unit 6 moves multiple outer diameter drive units 6 to any position in the vertical direction via an actuator capable of position control, such as a servo motor (not shown).

[0062] Multiple outer diameter displacement sensors 5 move between a standby position Zu above the upper end of the stator body 100, which is placed on the mounting platform 4, and the lower end of the stator body 100. At this time, the multiple outer diameter displacement sensors 5 measure the coordinate position by using any position between the upper and lower ends of the stator body 100 as the measuring surface and the welded part 106 on the measuring surface as the measuring part.

[0063] Multiple inner diameter displacement sensors 7 are sensors that measure the measurement portion of the through hole 105 in the stator body 100. Multiple inner diameter displacement sensors 7 are sensors that measure the amount of displacement from a reference value. In this embodiment, the inner diameter displacement sensors 7 are contact-type displacement sensors. Multiple inner diameter displacement sensors 7 are supported by an inner diameter drive device 8 and are movable in the vertical direction. Multiple inner diameter displacement sensors 7 are located on a plane perpendicular to the axis P of the stator body 100 mounted on the mounting platform 4, and on an annulus centered on the axis P of the stator body 100. Furthermore, multiple inner diameter displacement sensors 7 are configured to pass through the through hole 105 of the stator body 100.

[0064] Multiple inner diameter displacement sensors 7 are positioned within the through hole 105, overlapping with the linear weld portions 106 when viewed radially from the stator body 100. Specifically, the multiple inner diameter displacement sensors 7 simultaneously move by the same amount in the same direction along the linear portion (hereinafter referred to as the weld portion projection range 107) of the inner circumferential surface of the through hole 105 that overlaps with the linear weld portions 106 when viewed radially from the stator body 100. Furthermore, the multiple inner diameter displacement sensors 7 use a plane orthogonal to the axis P of the stator body 100 mounted on the mounting platform 4 as the measuring plane, and measure the weld portion projection range 107 on the measuring plane. The multiple inner diameter displacement sensors 7 are connected to the control device 18. The coordinate positions of each of the multiple inner diameter displacement sensors 7 are pre-calculated with the reference position P0 as the origin.

[0065] The inner diameter drive unit 8 is a drive device capable of moving multiple inner diameter displacement sensors 7 linearly in the vertical direction. The inner diameter drive unit 8 supports multiple outer diameter displacement sensors 5 from a frame (not shown) below the stator body 100 mounted on the mounting platform 4. The inner diameter drive unit 8 is connected to the control unit 18. The inner diameter drive unit 8 moves multiple inner diameter drive units 8 to any position in the vertical direction via an actuator capable of position control, such as a servo motor.

[0066] Multiple internal diameter displacement sensors 7 move between a standby position below the lower end of the stator body 100 placed on the mounting platform 4 and the upper end of the stator body 100. At this time, the multiple internal diameter displacement sensors 7 measure the coordinate position by using any position between the upper and lower ends of the stator body 100 as the measuring surface and the weld projection range 107 on the measuring surface as the measuring part.

[0067] like Figures 4 to 6 As shown, the control device 18 is a device for controlling multiple outer diameter displacement sensors 5, an outer diameter drive device 6, multiple inner diameter displacement sensors 7, and an inner diameter drive device 8. The control device 18 is essentially connected to a CPU, ROM, RAM, HDD, etc., via a busbar. Alternatively, the control device 18 can also be a structure composed of a single-chip LSI, etc. The control device 18 stores various programs and data for controlling the operation of the multiple outer diameter displacement sensors 5, outer diameter drive devices 6, multiple inner diameter displacement sensors 7, and inner diameter drive devices 8. The control device 18 sends control signals to the multiple outer diameter displacement sensors 5, outer diameter drive devices 6, multiple inner diameter displacement sensors 7, and inner diameter drive devices 8. Furthermore, the control device 18 includes an acquisition unit 12, a diameter calculation unit 13, a predicted temperature calculation unit 14, a predicted change calculation unit 15, a diameter prediction unit 16, and a printing unit 17.

[0068] The temperature measuring unit 9 measures the actual body temperature tr of the stator body 100 when the position of the measurement point is measured by the position measuring unit 2 within the stator body 100. The temperature measuring unit 9 includes a thermometer 10 and a control device 18. In this embodiment, the thermometer 10 is a non-contact infrared thermometer. The thermometer 10 is mounted on the outer diameter displacement sensor 5. The thermometer 10 begins measurement when it receives a signal indicating that the stator body 100 is mounted on the mounting stage 4. The thermometer 10 measures the temperature at multiple locations, including the welded portion 106 and the unwelded portion. Furthermore, the thermometer 10 calculates the average temperature of the stator body 100, i.e., the actual body temperature tr, based on the multiple measurement results. The thermometer 10 is connected to the control device 18. The control device 18 stores various programs and data for controlling the operation of the thermometer 10. The control device 18 sends control signals to the thermometer 10.

[0069] The time measuring unit 11 measures the elapsed time, T1, from the measurement start time T0, which is the time elapsed after a predetermined time has elapsed since the completion of welding of the stator body 100. The time measuring unit 11 is included in the control device 18. The control device 18 stores various programs and data to enable the time measuring unit 11 to control the time measurement. The time measuring unit 11 is connected to the welding device 300, which is located upstream of the stator diameter measuring device 1. If the time measuring unit 11 receives a welding completion signal from the welding device 300 indicating the completion of welding of the stator body 100, it begins measurement from the moment a predetermined time has elapsed since receiving the welding completion signal, using this as the measurement start time T0. The time measuring unit 11 measures the time from the measurement start time T0 until the position measuring unit 2 begins measurement, using this as the welding elapsed time T1.

[0070] The acquisition unit 12 acquires the welding elapsed time T1 measured by the time measurement unit 11, the actual main body temperature tr measured by the temperature measurement unit 9, and the coordinate position of the measurement part relative to the reference position P0 measured by the position measurement unit 2. Additionally, the acquisition unit 12 acquires values ​​calculated by the diameter calculation unit 13, the estimated temperature calculation unit 14, the estimated change calculation unit 15, and the diameter estimation unit 16. The acquisition unit 12 is included in the control device 18. The control device 18 stores various programs and data for the acquisition unit 12 to acquire measured and calculated values. The acquisition unit 12 is connected to the position measurement unit 2, the temperature measurement unit 9, the time measurement unit 11, the diameter calculation unit 13, the estimated temperature calculation unit 14, the estimated change calculation unit 15, and the diameter estimation unit 16. When acquiring each measured value, the acquisition unit 12 records the stator body 100 to be welded and each measured value in an associated state.

[0071] The diameter calculation unit 13 uses the coordinate position of the measuring part relative to the reference position P0 to calculate at least one of the actual outer diameter D1r and the actual inner diameter D2r of the stator body 100 at the welding elapsed time T1 (see reference). Figure 2 The actual outer diameter D1r is the diameter of the largest circle calculated from the position coordinates of the welded part 106 measured by the position measuring unit 2. The actual inner diameter D2r is the diameter of the smallest circle calculated from the position coordinates of the welded part projection range 107 measured by the position measuring unit 2. The diameter calculation unit 13 is included in the control device 18. The control device 18 stores various programs and data to enable the diameter calculation unit 13 to calculate the actual outer diameter D1r and actual inner diameter D2r of the stator body 100. The diameter calculation unit 13 obtains from the acquisition unit 12 the coordinate position of the measuring part measured by the position measuring unit 2 relative to the reference position P0 of the stator body 100, which is the object of calculation.

[0072] When calculating the actual outer diameter D1r of the stator body 100, the diameter calculation unit 13 obtains the position coordinates of the welded portions 106 on the measuring surface from the acquisition unit 12. The diameter calculation unit 13 calculates the diameter of the circle passing through 3 of the 8 position coordinates of the welded portions 106 on the measuring surface. The diameter calculation unit 13 calculates the diameter of the largest circle among the calculated diameters as the actual outer diameter D1r of the stator body 100 (refer to...). Figure 12 ).

[0073] When calculating the actual inner diameter D2r of the stator body 100, the diameter calculation unit 13 obtains the position coordinates of the weld projection range 107 on the measuring surface from the acquisition unit 12. The diameter calculation unit 13 calculates the diameter of the circle passing through 3 of the 8 obtained position coordinates of the weld projection range 107. The diameter calculation unit 13 calculates the diameter of the circle with the smallest diameter among the calculated circles as the actual inner diameter D2r of the stator body 100 (refer to...). Figure 12 ).

[0074] The predicted temperature calculation unit 14 calculates the predicted temperature te based on the predicted temperature database DB1, according to the welding elapsed time T1 and the actual body temperature tr. The predicted temperature calculation unit 14 is included in the control device 18. The control device 18 stores various programs and data for the predicted temperature calculation unit 14 to calculate the predicted temperature te. The predicted temperature calculation unit 14 has a predicted temperature database DB1 (see reference) that shows the relationship between the actual body temperature tr and the predicted temperature te at the welding elapsed time T1. Figure 7 The predicted temperature te is the temperature of the stator body 100 at the measurement start time T0, predicted based on the actual body temperature tr at the welding elapsed time T1. The predicted temperature database DB1 is constructed by measuring the time series changes of the actual body temperature tr for each actual body temperature at the measurement start time T0. The predicted temperature database DB1 can calculate the predicted temperature te based on the welding elapsed time T1 and the actual body temperature tr of the stator body 100 at the welding elapsed time T1.

[0075] like Figure 4 , Figure 7 and Figure 8As shown, the predicted temperature calculation unit 14 acquires the welding elapsed time T1 and the actual body temperature tr from the acquisition unit 12. Based on the acquired welding elapsed time T1 and actual body temperature tr, the predicted temperature calculation unit 14 calculates the predicted temperature te according to the predicted temperature database DB1. Furthermore, when the welding elapsed time T1 is constant, the predicted temperature calculation unit 14 calculates the predicted temperature te based on the actual body temperature tr according to the predicted temperature database DB1. That is, the predicted temperature database DB1 can be represented as a temperature prediction formula showing the relationship between the actual body temperature tr and the predicted temperature te under a specified welding elapsed time T1 (see reference). Figure 8 The temperature estimation calculation unit 14 uses a temperature estimation formula to calculate the estimated temperature te based on the actual body temperature tr at the specified welding elapsed time T1.

[0076] like Figure 4 and Figure 9 As shown, the estimated change calculation unit 15 calculates the changes in the actual outer diameter D1r and actual inner diameter D2r of the stator body 100 at any welding elapsed time T1. The estimated change calculation unit 15 is included in the control device 18. The control device 18 stores various programs and data for the estimated change calculation unit 15 to calculate the changes in the actual outer diameter D1r and actual inner diameter D2r. The estimated change calculation unit 15 has an estimated change database DB2 (see reference) that shows the relationship between the welding elapsed time T1 and the estimated change Ce of the actual outer diameter D1r and actual inner diameter D2r of the stator body 100 according to each estimated temperature te. Figure 9 The estimated change Ce is estimated as the amount of shrinkage that occurs before the actual outer diameter D1r and actual inner diameter D2r of the stator body 100 reach the reference body temperature at any welding elapsed time T1, which is an arbitrary estimated temperature te. The reference body temperature is the body temperature at which the reference values ​​of the actual outer diameter D1r and actual inner diameter D2r of the stator body 100 are measured. In this embodiment, the reference body temperature is 23°C as a standard state. The estimated change database DB2 is constructed by measuring the time series change of the estimated change Ce for each actual body temperature tr at the measurement start time T0. The estimated change database DB2 can calculate the estimated change Ce of the actual outer diameter D1r and actual inner diameter D2r based on the estimated temperature te and the welding elapsed time T1.

[0077] The estimated change calculation unit 15 acquires the welding elapsed time T1 and the estimated temperature te from the acquisition unit 12. Based on the acquired welding elapsed time T1 and estimated temperature te, the estimated change calculation unit 15 calculates the estimated change Ce of the actual outer diameter D1r and the actual inner diameter D2r using the estimated change database DB2. Furthermore, based on the estimated change database DB2, the estimated change calculation unit 15 calculates the estimated change Ce for each estimated temperature te based on the welding elapsed time T1. That is, the estimated change database DB2 can be represented as a change estimation formula showing the relationship between the welding elapsed time T1 at the estimated temperature te and the estimated change Ce of the actual outer diameter D1r and the actual inner diameter D2r. The estimated change calculation unit 15 has a change estimation formula for each estimated temperature te. Using the change estimation formula, the estimated change calculation unit 15 calculates the estimated change Ce of the actual outer diameter D1r and the actual inner diameter D2r based on the welding elapsed time T1 at any estimated temperature te. The change estimation formula can be, for example, expressed as y = ax 2 +bx+x (y: change, x: welding time T1, a, b, c: coefficients) is shown.

[0078] The diameter estimation unit 16 calculates at least one of the estimated outer diameter D1e and estimated inner diameter D2e of the stator body 100 at the reference body temperature based on at least one of the calculated actual outer diameter D1r and actual inner diameter D2r, and a calculated estimated change Ce. The diameter estimation unit 16 is included in the control device 18. The control device 18 stores various programs and data for the diameter estimation unit 16 to calculate the estimated outer diameter D1e and estimated inner diameter D2e. The estimated outer diameter D1e and estimated inner diameter D2e are the outer diameter and inner diameter of the stator body 100 at the reference body temperature.

[0079] The diameter estimation unit 16 obtains at least one of the actual outer diameter D1r and the actual inner diameter D2r, and at least one of the estimated change in the outer diameter and the inner diameter Ce, from the acquisition unit 12. The diameter estimation unit 16 calculates at least one of the estimated outer diameter D1e and the estimated inner diameter D2e based on the obtained at least one of the actual outer diameter D1r and the actual inner diameter D2r, and the estimated change in the actual outer diameter D1r and the actual inner diameter D2r Ce.

[0080] The printing unit 17 prints identification marks, etc., on the stator body 100 after measurement. The printing unit 17 includes a printing device (not shown) and a control device 18. When the printing device acquires a signal that calculates at least one of the estimated outer diameter D1e and estimated inner diameter D2e of the stator body 100 to be measured, it prints an identification number, etc., on the stator body 100 using ink or laser. The printed identification number, etc., is associated with the measured value and the calculated value of the stator body 100 to be measured.

[0081] Next, use Figure 4, Figures 10 to 12 The inspection step S100 of the stator diameter measurement method using the stator diameter measuring device 1 of Embodiment 1 will be described. Figure 10 This is a flowchart of the inspection process for the stator diameter measuring device. Figure 11 This is a rough cross-sectional view showing the measuring surface of the stator diameter measuring device. Figure 12 This is a schematic diagram showing the actual outer diameter D1r and actual inner diameter D2r of the stator diameter measuring device.

[0082] like Figure 10 As shown, the inspection process S100 includes a time measurement process S110, a temperature measurement process S120, a position measurement process S130, a diameter calculation process S140, a predicted temperature calculation process S150, a predicted change calculation process S160, a diameter prediction process S170, and a printing process S180.

[0083] like Figure 11 As shown, in the initial state of the stator diameter measuring device 1, multiple outer diameter displacement sensors 5 are in standby position Zu. Multiple inner diameter displacement sensors 7 are in standby position Zd. The stator diameter measuring device 1 is in a state where the stator body 100 can be moved from the welding device 300 into the mounting platform 4 via a conveying device (not shown).

[0084] like Figure 4 , Figure 10 and Figure 11 As shown, the time measurement process S110 measures the welding elapsed time T1, which is the elapsed time from the measurement start time T0, which is the time elapsed since the welding of the stator body 100 by the welding device 300 was completed. In the time measurement process S110, the time measurement unit 11 takes the moment when the predetermined time has elapsed since the welding completion signal from the welding device 300 is received as the measurement start time T0, and starts measuring the time. The time measurement unit 11 continues to measure until the stator body 100 placed on the mounting stage 4 of the stator diameter measuring device 1 begins to be measured. The time measurement unit 11 sends the welding elapsed time T1 from the measurement start time T0 to the start of the measurement of the stator body 100 to the acquisition unit 12. The time measurement process S110 ends when a signal indicating that the stator body 100 has started to be measured by the stator diameter measuring device 1 is received. The inspection process S100 transfers to the temperature measurement process S120 after the time measurement process S110 ends.

[0085] In temperature measurement step S120, the actual body temperature tr of the stator body 100 is measured when the position measurement unit 2 measures the position of the measurement location. In temperature measurement step S120, when the temperature measurement unit 9 receives a signal indicating that the stator body 100 is mounted on the mounting stage 4, it begins measuring the actual body temperature tr of the stator body 100 using the thermometer 10. The temperature measurement unit 9 measures the temperature at multiple locations of the stator body 100 using the thermometer 10. The temperature measurement unit 9 calculates the actual body temperature tr based on the measurement results at multiple locations. The temperature measurement unit 9 sends the actual body temperature tr to the acquisition unit 12, completing temperature measurement step S120. After temperature measurement step S120 is completed, inspection step S100 proceeds to position measurement step S130.

[0086] In the position measurement process S130, at least one of the plurality of welded parts 106 and the inner circumferential surface of the stator body 100 that overlaps with the plurality of welded parts 106 when viewed radially from the stator body 100 is used as the measurement location, and the position coordinates relative to the reference position P0 are measured. In this embodiment, the measurement location of the actual outer diameter D1r is the coordinate position of the welded part 106 on the measurement surface Sa at the upper end, the measurement surface Sc at the lower end, and the measurement surface Sb (hereinafter referred to as "the measurement surface Sb of the middle part") at any position between the measurement surface Sa at the upper end and the measurement surface Sc at the lower end, which is placed on the mounting table 4. In addition, the measurement surface of the actual inner diameter D2r is the coordinate position of the welded part projection range 107 on the measurement surface n at predetermined intervals from the measurement surface S1 at the lower end of the stator body 100 placed on the mounting table 4 to the measurement surface S(n) at the upper end.

[0087] In the position measurement process S130, multiple outer diameter displacement sensors 5 of the position measurement unit 2 move from the standby position Zu above the stator body 100 mounted on the mounting table 4 to the upper measuring surface Sa. The multiple outer diameter displacement sensors 5 use eight welded portions 106 on the upper measuring surface Sa as measuring points and measure the coordinate positions of the measuring points relative to the reference position P0. The control device 18 acquires the position coordinates measured by the multiple outer diameter displacement sensors 5. Next, the multiple outer diameter displacement sensors 5 move from the upper measuring surface Sa to the middle measuring surface Sb. The multiple outer diameter displacement sensors 5 use eight welded portions 106 on the middle measuring surface Sb as measuring points and measure the coordinate positions of the measuring points relative to the reference position P0. Next, the multiple outer diameter displacement sensors 5 move from the middle measuring surface Sb to the lower measuring surface Sc. The multiple outer diameter displacement sensors 5 use eight welded portions 106 on the lower measuring surface Sc as measuring points and measure the coordinate positions of the measuring points relative to the reference position P0.

[0088] In the position measurement process S130, multiple inner diameter displacement sensors 7 of the position measurement unit 2 move from their standby position Zd, which is located below the stator body 100 on the mounting table 4, to the measurement surface S1, which is the lower end of the welding part projection range 107. The multiple inner diameter displacement sensors 7 use eight welding part projection ranges 107 on the first measurement surface S1 as measurement points and measure the coordinate positions of these measurement points relative to the reference position P0. The control device 18 acquires the position coordinates measured by the multiple inner diameter displacement sensors 7. Next, the multiple inner diameter displacement sensors 7 move to the second measurement surface S2, which is located at a predetermined interval above the first measurement surface S1. Multiple outer diameter displacement sensors 5 use eight welding part projection ranges 107 on the second measurement surface S2 as measurement points and measure the coordinate positions of these measurement points relative to the reference position P0. Similarly, multiple inner diameter displacement sensors 7 use the projection range 107 of 8 welded parts on the nth measuring surface S(n), which is the upper end measuring surface, as the measuring location, and measure the coordinate position of the measuring location relative to the reference position P0.

[0089] The position measuring unit 2 sends the coordinate positions of the welded portions 106 on each measuring surface and the coordinate positions of the projected ranges 107 of the welded portions on each measuring surface to the acquisition unit 12. After the position measuring unit 2 completes the measurement of the welded portions 106 on each measuring surface and the measurement of the projected ranges 107 of the welded portions on each measuring surface, the position measuring unit 2 completes the position measuring process S130. After the position measuring process S130 is completed, the inspection process S100 transfers to the diameter calculation process S140.

[0090] In the diameter calculation step S140, at least one of the actual outer diameter D1r and actual inner diameter D2r of the stator body 100 at the time T1 of welding is calculated using the position of the measuring part relative to the reference position P0. In the diameter calculation step S140, when calculating the actual outer diameter D1r of the stator body 100, the diameter calculation unit 13 obtains from the acquisition unit 12 the position coordinates of the welded part 106 on the measuring surface Sa at the upper end, the measuring surface Sb at the middle part, and the measuring surface Sc at the lower end of the stator body 100 along the axial direction.

[0091] like Figure 12As shown, the diameter calculation unit 13 obtains position coordinates Pc8 from the position coordinates Pc1 of the welded portion 106 on the measuring surface Sc at the lower end. The diameter calculation unit 13 calculates the diameter of the circle passing through the three positions in position coordinates Pc8 based on the obtained position coordinates Pc1. Similarly, the diameter calculation unit 13 calculates the diameter of the circle passing through the three positions in position coordinates Pc4, Pc7, and Pc8 on the measuring surface Sb at the middle end. When the diameter of the circle passing through position coordinates Pc4, Pc7, and Pc8 on the measuring surface Sc at the lower end is the largest among the diameters calculated on each measuring surface, the diameter calculation unit 13 calculates the diameter of the circle passing through position coordinates Pc4, Pc7, and Pc8 as the actual outer diameter D1r of the stator body 100.

[0092] like Figure 4 , Figure 10 and Figure 11 As shown, when calculating the actual inner diameter D2r of the stator body 100 in the diameter calculation process S140, the diameter calculation unit 13 obtains from the acquisition unit 12 the position coordinates of the weld projection range 107 on each of the first measurement surface S1 to the nth measurement surface S(n) in the axial direction of the stator body 100.

[0093] like Figure 12 As shown, the diameter calculation unit 13 obtains position coordinates P18, for example, from the position coordinates P11 of the weld projection range 107 on the measuring surface S1. The diameter calculation unit 13 calculates the diameter of the circle passing through three points in position coordinates P18 based on the obtained position coordinates P11. Similarly, the diameter calculation unit 13 calculates the diameter of the circle passing through three points in position coordinates P11, P14, and P17 on each of the obtained measuring surfaces. When the diameter of the circle passing through position coordinates P11, P14, and P17 on the measuring surface S1 is the smallest among the diameters of the circles calculated on each measuring surface, the diameter calculation unit 13 calculates the diameter of the circle passing through position coordinates P11, P14, and P17 as the actual inner diameter D2r of the stator body 100.

[0094] like Figure 4 , Figure 10 and Figure 11 As shown, the diameter calculation unit 13 sends the actual outer diameter D1r and the actual inner diameter D2r to the acquisition unit 12, completing the diameter calculation process S140. After the diameter calculation process S140 is completed, the inspection process S100 moves to the estimated temperature calculation process S150.

[0095] In the estimated temperature calculation step S150, based on the estimated temperature database DB1, which shows the relationship between the actual body temperature tr at the welding elapsed time T1 and the estimated temperature te of the stator body 100 at the measurement start time T0, the estimated temperature te is calculated according to the welding elapsed time T1 and the actual body temperature tr (see reference). Figure 7 and Figure 8 In the temperature estimation calculation step S150, the temperature estimation calculation unit 14 acquires the welding elapsed time T1 and the actual body temperature tr from the acquisition unit 12. Based on the acquired welding elapsed time T1 and actual body temperature tr, the temperature estimation calculation unit 14 calculates the estimated temperature te3 using the estimated temperature database DB1. Furthermore, in this embodiment, the welding elapsed time T1 is constant due to the interval between the welding device 300 and the stator diameter measuring device 1 and the transport speed from the welding device 300 to the stator diameter measuring device 1. Therefore, the temperature estimation calculation unit 14 calculates the estimated temperature te3 based on the actual body temperature tr using a temperature estimation formula. The temperature estimation calculation unit 14 sends the estimated temperature te3 to the acquisition unit 12, completing the temperature estimation calculation step S150. After the temperature estimation calculation step S150 is completed, the inspection step S100 proceeds to the estimated change calculation step S160.

[0096] In the estimated change calculation step S160, based on the estimated change database DB2 which shows the relationship between the estimated change Ce of the outer diameter D1 and inner diameter D2 of the stator body 100 at each estimated temperature te and welding elapsed time T1, the estimated change Ce is calculated according to the calculated estimated temperature te3 and welding elapsed time T1 (see reference). Figure 9 In the estimated change calculation step S160, the estimated change calculation unit 15 acquires the welding elapsed time T1 and the estimated temperature te3 from the acquisition unit 12. Based on the acquired welding elapsed time T1 and estimated temperature te3, the estimated change calculation unit 15 calculates the estimated change Ce of the outer diameter and inner diameter using the estimated change database DB2. Additionally, based on the welding elapsed time T1 at the estimated temperature te3 calculated using the change estimation formula derived from the estimated change database DB2, the estimated change calculation unit 15 calculates the estimated change Ce of the actual outer diameter D1r and actual inner diameter D2r. The estimated change calculation unit 15 sends the estimated change Ce to the acquisition unit 12, completing the estimated change calculation step S160. After the estimated change calculation step S160 is completed, the inspection step S100 proceeds to the diameter estimation step S170.

[0097] In the diameter estimation step S170, at least one of the estimated outer diameter D1r and estimated inner diameter D2r of the stator body 100 at the reference body temperature is calculated based on at least one of the calculated actual outer diameter D1r and actual inner diameter D2r and the calculated estimated change amount Ce. In the diameter estimation step S170, the diameter estimation unit 16 acquires at least one of the actual outer diameter D1r and actual inner diameter D2r, and at least one of the estimated change amount Ce of the actual outer diameter D1r and actual inner diameter D2r, from the acquisition unit 12. The diameter estimation unit 16 calculates at least one of the estimated outer diameter D1e and estimated inner diameter D2e based on at least one of the acquired actual outer diameter D1r and actual inner diameter D2r, and at least one of the estimated change amount Ce of the actual outer diameter D1r and actual inner diameter D2r. The diameter estimation unit 16 sends the estimated outer diameter D1e and estimated inner diameter D2e to the acquisition unit 12, completing the diameter estimation step S170. After the diameter estimation process S170 is completed, the inspection process S100 is transferred to the printing process S180.

[0098] In the printing process S180, an identification number or similar identifier is printed on the stator body 100. During printing process S180, the printing unit 17 prints identification marks or similar identifiers on the stator body 100 after measurement. The inspection process S100 concludes after printing process S180. The stator diameter measuring device 1 removes the stator body 100 via a conveying device (not shown).

[0099] The stator diameter measuring device 1, with the above-described structure, can calculate the estimated inner diameter D2e or estimated outer diameter D1e of the stator body 100 at the reference body temperature by measuring the welding elapsed time T1, the actual body temperature tr, and the position coordinates of the measuring part relative to the reference position P0, based on the estimated temperature database DB1 and the estimated change database DB2. Therefore, in the stator production line L equipped with the stator diameter measuring device 1, necessary measurements can be performed without cooling the welded stator body 100 to the reference body temperature. That is, it is not necessary to leave the stator body 100 until the actual body temperature tr of the stator body 100 reaches the reference body temperature. Furthermore, since the stator body 100 can be measured even immediately after welding, the transport time and transport distance from the welding device 300 to the stator diameter measuring device 1 can be shortened.

[0100] Furthermore, the temperature measurement unit 9 measures the actual main body temperature tr, and the position measurement unit 2 measures the measurement location, preferably when the difference between the actual main body temperature tr and the reference main body temperature is large. The greater the difference between the actual main body temperature tr and the reference main body temperature, the greater the change in the stator body 100 caused by thermal expansion compared to the change in the stator body 100 caused by other factors. Therefore, the accuracy of the estimated temperature te calculated by the estimated temperature calculation unit 14, and the actual outer diameter D1r and actual inner diameter D2r calculated by the diameter calculation unit 13 are improved.

[0101] Furthermore, the temperature estimation calculation unit 14 can calculate the estimated temperature te using a temperature estimation formula. The change estimation calculation unit 15 can calculate the estimated change Ce using a change estimation formula. Therefore, by measuring the actual body temperature tr of the stator body 100 and the position coordinates of the measuring part relative to the reference position P0 during the welding elapsed time T1, the stator diameter measuring device 1 can calculate at least one of the estimated outer diameter D1e and the estimated inner diameter D2e based on the temperature estimation formula and the change estimation formula.

[0102] Furthermore, the diameter calculation unit 13 calculates the diameter of the largest circle among the circles passing through the coordinate positions of the weld portion 6 on the measuring surface as the actual outer diameter D1r of the stator body 100. Then, the diameter calculation unit 13 calculates the diameter of the smallest circle among the circles passing through the coordinate positions of the weld portion projection range 107 on the measuring surface as the actual inner diameter D2r of the stator body 100. Thus, the calculation of the actual outer diameter D1r and the actual inner diameter D2r of the stator body 100 becomes easier, improving the production efficiency of the stator production line L.

[0103] (Implementation Method 2)

[0104] The following uses Figure 4 and Figure 13 Embodiment 2 of the stator diameter measuring device 1 of the present invention will be described. Figure 13 This is a perspective view showing the schematic structure of the stator body 100. In the following description, the same reference numerals are used for structures identical to those in Embodiment 1, and descriptions are omitted; only the parts that differ from Embodiment 1 are described.

[0105] like Figure 4 As shown, the stator diameter measuring device 1 includes a position measuring unit 2, a temperature measuring unit 9, a time measuring unit 11, an acquisition unit 12, a diameter calculation unit 13, an estimated temperature calculation unit 14, an estimated change calculation unit 15, a diameter estimation unit 16, a printing unit 17, and a confirmation measuring unit 19.

[0106] The verification measurement unit 19 measures the position of the measuring part relative to the reference position P0 at the reference body temperature for the stator body 100 measured by the position measurement unit 2. The verification measurement unit 19 also functions as the position measurement unit 2. The verification measurement unit 19 uses the same measuring part as the actual outer diameter D1r and actual inner diameter D2r measured by the position measurement unit 2 as the measuring part, and measures the position relative to the reference position P0.

[0107] Next, use Figure 13 The inspection process S100 of the stator diameter measuring device 1 in Embodiment 2 will be described. The inspection process S100 includes a time measurement process S110, a temperature measurement process S120, a position measurement process S130, a diameter calculation process S140, a predicted temperature calculation process S150, a predicted change calculation process S160, a diameter prediction process S170, a printing process S180, and a confirmation measurement process S190.

[0108] In the verification measurement process S190, the variation estimation formula is corrected based on the difference between at least one of the estimated outer diameter D1e and estimated inner diameter D2e of the stator body 100 and at least one of the actual outer diameter D1r and actual inner diameter D2r of the stator body 100 at the reference body temperature. In the verification measurement process S190, the verification measurement unit 19 uses the same measurement location as the actual outer diameter D1r and actual inner diameter D2r measured by the position measurement unit 2 as the measurement location, and measures the position coordinates relative to the reference position P0. Next, the acquisition unit 12 acquires the coordinate position of the measurement location at the reference body temperature relative to the reference position P0 of the stator body 100. Then, the diameter calculation unit 13 calculates at least one of the actual outer diameter D1r and actual inner diameter D2r of the stator body 100 at the reference body temperature based on the coordinate position of the measurement location at the reference body temperature.

[0109] The estimation change calculation unit 15 corrects the coefficients of the estimation change formula so as to reduce the difference between at least one of the estimated outer diameter D1e and estimated inner diameter D2e of the stator body 100 calculated in the diameter estimation process S180 and at least one of the actual outer diameter D1r and actual inner diameter D2r of the stator body 100 at the calculated reference body temperature.

[0110] The estimation change calculation unit 15 calculates the difference between at least one of the actual outer diameter D1r and actual inner diameter D2r of the stator body 100, corresponding to at least one of the estimated outer diameter D1e and estimated inner diameter D2e of the stator body 100 that has already been calculated. By correcting the coefficients of the estimation formula to reduce the calculated difference, the estimation change calculation unit 15 can calculate at least one of the estimated inner diameter D2e or estimated outer diameter D1e of the stator body 100 based on the tendency of thermal deformation caused by welding of the stator body 100. This improves the inspection accuracy of the inspection process S100 and increases the production efficiency of the stator production line L.

[0111] (Other implementation methods)

[0112] The embodiments of the present invention have been described above, but these embodiments are merely examples for implementing the present invention. Therefore, the present invention is not limited to the above embodiments, and the above embodiments can be appropriately modified for implementation without departing from the scope of the present invention.

[0113] In the above embodiment, the diameter calculation unit 13 calculates the actual outer diameter D1r and the actual inner diameter D2r based on the position coordinates of the welded part 106 and the position coordinates of the welded part projection range 107 measured by the position measuring unit 2. However, the diameter calculation unit 13 may also further calculate the roundness of the actual outer diameter D1r and the actual inner diameter D2r based on the position coordinates of the welded part 106 and the position coordinates of the welded part projection range 107 measured by the position measuring unit 2.

[0114] The diameter calculation unit 13 calculates at least one of the following using the center method: the roundness of the circle passing through the position coordinates of the weld portion 106 intersecting the measuring surface relative to the reference position P0, and the roundness of the circle passing through the position coordinates of the weld portion projection range 107 of the stator body 100, which overlaps with the weld portion 106 and intersects with multiple planes perpendicular to the axis P of the stator body 100 when viewed radially from the stator body 100, wherein the measuring surface is a plane perpendicular to the axis P of the stator body 100.

[0115] When calculating the roundness of the actual outer diameter D1r of the stator body 100, the diameter calculation unit 13 calculates the roundness of the circle using the center method based on the deviation of the position coordinates of the welded portion 106 on the upper end measurement surface Sa, the middle measurement surface Sb, and the lower end measurement surface Sc obtained from the acquisition unit 12. Similarly, when calculating the roundness of the actual inner diameter D2r of the stator body 100, the diameter calculation unit 13 calculates the roundness of the circle using the center method based on the deviation of the position coordinates of the welded portion projection range 107 on each measurement surface obtained from the acquisition unit 12. The center method includes, for example, the least squares center method, the minimum region center method, the maximum inscribed circle center method, and the minimum circumscribed circle center method. The diameter calculation unit 13 calculates the largest roundness among the calculated roundness of each circle as the roundness of the actual outer diameter D1r and the actual inner diameter D2r of the stator body 100.

[0116] The diameter calculation unit 13 calculates the actual outer diameter D1r of the stator body 100 based on the coordinate positions of the multiple welded portions 106 of the stator body 100 measured by the position measurement unit 2. Furthermore, the diameter calculation unit 13 calculates the roundness of the actual outer diameter D1r using the center method. Similarly, the diameter calculation unit 13 calculates the actual inner diameter D2r of the stator body 100 based on the coordinate positions of the welded portion projection range 107 of the stator body 100 measured by the position measurement unit 2, and calculates the roundness of the actual inner diameter D2r using the center method. Therefore, since multiple measurement results are calculated using the position coordinates measured by the position measurement unit 2, the production efficiency of the stator production line L can be improved.

[0117] In the above embodiment, the position measuring unit 2 measures the position coordinates of the welded portion 106 on the upper measuring surface Sa, the lower measuring surface Sc, and the middle measuring surface Sb of the stator body 100 placed on the mounting platform 4 along the axial direction. However, the measuring surfaces of the position measuring unit 2 are not limited to the upper measuring surface Sa, the lower measuring surface Sc, and the middle measuring surface Sb. The measuring surfaces of the position measuring unit 2 can also be arbitrarily set according to the shape of the stator body 100, the position of the welded portion 106, etc.

[0118] In the above embodiment, the position measuring unit 2 uses any position along the axial direction of the stator body 100 as the measuring surface and the welded portion 106 on the measuring surface as the measuring location for measurement. However, the position measuring unit 2 may also use a position on the measuring surface that is different from the welded portion 106 as the measuring location for measurement.

[0119] In the above embodiment, the position measuring unit 2 uses any position along the axial direction of the stator body 100 as the measuring surface and the projection range 107 of the weld portion on the measuring surface as the measuring location. However, the position measuring unit 2 may also use a position on the measuring surface that is different from the projection range 107 of the weld portion as the measuring location.

[0120] In the above embodiment, the multiple outer diameter displacement sensors 5 of the position measuring unit 2 measure while moving downward from the standby position Zu above the stator body 100. Similarly, the multiple inner diameter displacement sensors 7 of the position measuring unit 2 measure while moving upward from the standby position Zd below the stator body 100. However, the standby positions and moving directions of the multiple outer diameter displacement sensors 5 and the multiple inner diameter displacement sensors 7 are not limited to this embodiment. The multiple outer diameter displacement sensors 5 may also measure while moving upward from the standby position below the stator body 100. Similarly, the multiple inner diameter displacement sensors 7 may measure while moving downward from the standby position above the stator body 100.

[0121] In the above embodiment, the position measuring unit 2, temperature measuring unit 9, time measuring unit 11, acquisition unit 12, diameter calculation unit 13, estimated temperature calculation unit 14, estimated change calculation unit 15, diameter estimation unit 16, and printing unit 17 all have the same control device 18. However, the position measuring unit 2, temperature measuring unit 9, time measuring unit 11, acquisition unit 12, diameter calculation unit 13, estimated temperature calculation unit 14, estimated change calculation unit 15, diameter estimation unit 16, and printing unit 17 may each have their own control device 18.

[0122] This invention is applicable to stator diameter measuring devices and stator diameter measuring methods.

Claims

1. A stator diameter measuring device for measuring the diameter of a stator body comprising a plurality of steel plates, wherein the plurality of steel plates are stacked in a manner with their outer peripheral sides welded along the thickness direction, characterized in that, have: The position measuring unit takes at least one of the welded portions of the plurality of steel plates and the inner circumferential surface of the stator body that overlaps with the plurality of welded portions when the stator body is viewed radially as a measuring point, and measures the position of the measuring point relative to a reference position. A temperature measuring unit measures the actual body temperature of the stator body when the position measuring unit measures the position of the measuring part. The time measurement unit measures the welding elapsed time, which is the elapsed time from the measurement start time, which is the time elapsed after a predetermined time since the completion of welding of the stator body; The acquisition unit acquires the welding elapsed time measured by the time measurement unit, the actual body temperature measured by the temperature measurement unit, and the position of the measurement part relative to the reference position measured by the position measurement unit. A diameter calculation unit uses the position of the measuring part relative to the reference position to calculate at least one of the actual outer diameter and the actual inner diameter of the stator body after the welding time has elapsed. The estimated temperature calculation unit has an estimated temperature database that shows the relationship between the actual body temperature at the welding elapsed time and the estimated temperature of the stator body at the measurement start time. The estimated temperature calculation unit calculates the estimated temperature based on the estimated temperature database, according to the welding elapsed time and the actual body temperature. The estimated change calculation unit has an estimated change database, which shows the relationship between the welding elapsed time and the estimated change of the outer diameter and inner diameter of the stator body for each estimated temperature. The estimated change calculation unit calculates the estimated change based on the estimated change database, according to the calculated estimated temperature and the welding elapsed time. as well as The diameter estimation unit calculates at least one of the estimated outer diameter and estimated inner diameter of the stator body at a reference body temperature, based on at least one of the calculated actual outer diameter and actual inner diameter, and the calculated estimated change. The time measurement unit measures the welding elapsed time from the start time of the measurement to the start time of the position measurement unit.

2. The stator diameter measuring device according to claim 1, characterized in that, The estimated temperature calculation unit uses a temperature estimation formula that shows the relationship between the actual body temperature and the estimated temperature over the welding elapsed time to calculate the estimated temperature based on the welding elapsed time and the actual body temperature. The estimated change calculation unit uses a change estimation formula that shows the relationship between the estimated change of the stator body at each estimated temperature and the welding elapsed time to calculate the estimated change based on the calculated estimated temperature and the welding elapsed time.

3. The stator diameter measuring device according to claim 2, characterized in that, The device includes a confirmation measurement unit that, for the stator body as measured by the position measurement unit, measures the position of the measurement part relative to the reference position at the reference body temperature. The confirmation measurement unit measures the position of the measurement part relative to the reference position at the reference body temperature. The acquisition unit acquires the position of the measuring part of the stator body relative to the reference position at the reference body temperature, as measured by the confirmation measurement unit. The diameter calculation unit calculates at least one of the actual outer diameter and actual inner diameter of the stator body at the reference body temperature. The estimated change calculation unit corrects the estimated change formula based on the difference between at least one of the estimated outer diameter and the estimated inner diameter of the stator body calculated and at least one of the actual outer diameter and the actual inner diameter of the stator body at the reference body temperature.

4. The stator diameter measuring device according to any one of claims 1 to 3, characterized in that, The diameter calculation unit calculates the diameter of the largest of the following circles as the actual outer diameter of the stator body, wherein these circles pass through three of the locations of the weld portion relative to the reference position that intersect with a plane orthogonal to the axis of the stator body.

5. The stator diameter measuring device according to claim 4, characterized in that, The diameter calculation unit calculates the diameter of the smallest of the following circles as the actual inner diameter of the stator body, wherein these circles pass through at least three locations on the inner circumferential surface of the stator body that overlap with the welded portion when viewed radially from the stator body and intersect with a plurality of planes perpendicular to the axis of the stator body.

6. The stator diameter measuring device according to claim 5, characterized in that, The diameter calculation unit uses the center method to calculate at least one of the following roundnesses of a circle: the roundness of the circle at the position of the welded part relative to the reference position, which intersects with a plane perpendicular to the axis of the stator body; and the roundness of the circle at the position on the inner circumferential surface of the stator body, which overlaps with the welded part and intersects with a plurality of planes perpendicular to the axis of the stator body, as viewed radially from the stator body.

7. A method for measuring the diameter of a stator, comprising measuring the diameter of a stator body having multiple steel plates, wherein the multiple steel plates are stacked in a state along the thickness direction and the outer peripheral sides are welded along the thickness direction, characterized in that... have: The time measurement process measures the welding elapsed time, which is the elapsed time from the measurement start time, which is the time elapsed after a specified time since the completion of welding of the stator body; In the position measurement process, at least one of the welded portions of the plurality of steel plates and the inner circumferential surface of the stator body that overlaps with the plurality of welded portions when viewed radially from the stator body is taken as the measurement location, and the position of the measurement location relative to the reference position is measured. The temperature measurement process measures the actual body temperature of the stator body when the position of the measuring part is measured by the position measurement process. The diameter calculation process involves using the position of the measuring part relative to the reference position to calculate at least one of the actual outer diameter and the actual inner diameter of the stator body after the welding time has elapsed. The inferred temperature calculation process involves an inferred temperature database that shows the relationship between the actual body temperature at the welding elapsed time and the inferred temperature of the stator body at the measurement start time. Based on this inferred temperature database, the inferred temperature is calculated according to the welding elapsed time and the actual body temperature. The process of calculating the estimated change amount involves a database showing the relationship between the estimated change amount of the outer diameter and inner diameter of the stator body at each estimated temperature and the welding elapsed time. Based on this database, the estimated change amount is calculated according to the calculated estimated temperature and the welding elapsed time. as well as The diameter estimation process involves calculating at least one of the calculated actual outer diameter and actual inner diameter, and the calculated estimated change, at a reference body temperature, the estimated outer diameter and estimated inner diameter of the stator body. In the time measurement process, the time from the start time of the measurement to the start time of the position measurement process is used as the welding elapsed time.

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