Dimensional measurement management system and dimensional measurement management method

Abstract

The object of the present invention is to provide a dimensional measurement management system and a dimensional measurement management method that can improve the economic efficiency of dimensional measurement. [Solution] The dimensional measurement management system of the present invention is characterized by comprising: a shape information extraction unit that extracts shape information to be measured from the design information of a target member; a measurement coordinate calculation unit that calculates measurement coordinates from the shape information extracted by the shape information extraction unit; a measurement area setting unit that sets a measurement area based on the measurement coordinates calculated by the measurement coordinate calculation unit and the dimensional information of a measuring instrument; an interference check unit that checks for interference by comparing the measurement area generated by the measurement area setting unit with the design information; and a measurement feasibility determination unit that determines whether measurement is possible or not based on the results of the interference check unit.

Description

Technical Field

[0001] The present invention relates to a dimensional measurement management system and a dimensional measurement management method.

Background Art

[0002] In manufacturing, geometric tolerance management has become common. As an example of geometric tolerance management, there is positional tolerance. For example, the center point of a circle must be within a circle with a diameter of 0.1 mm. Here, since the center of the circle cannot be directly measured, for example, a contact-type three-dimensional coordinate measuring instrument is used to measure the three-dimensional coordinates of a plurality of points on the circumference, and the obtained data is fitted to obtain the center of the circle.

[0003] Generally, gantry-type contact three-dimensional coordinate measuring instruments are used. A spherical contact attached to the tip of a probe is moved by a three-dimensional (X, Y, Z) movement mechanism and applied to a measurement object placed on a surface plate to obtain the three-dimensional coordinates of that point. Therefore, it is necessary to determine the points on the measurement object to be measured and confirm whether those points can be measured with a three-dimensional coordinate measuring instrument. At this time, the size of the three-dimensional coordinate measuring instrument is not only the size of the probe ball that contacts the measurement object, but also the size of the movement mechanism and the holding mechanism. Therefore, it is necessary to confirm whether the probe and the above mechanisms will collide (interfere) with the measurement object.

[0004] Patent Document 1 discloses a technology including an interference check device having a model number upper limit input unit for inputting the upper limit number of geometric models to be set for a modeling target that is an interference check target, a modeling processing unit for generating model candidates from the modeling target using geometric models not exceeding the model upper limit number, a processing operation amount upper limit setting unit for setting the upper limit amount of interference check calculations based on the calculation processing amount required for each process of a controller that controls the modeling target, a minimum inclusion volume model determination unit for determining, as the model of the modeling target, the model candidate with the smallest inclusion volume among the model candidates for which interference check calculation processing can be performed within the upper limit amount of calculation, and an interference check unit for performing an interference check between models using the determined model.

[0005] Patent Document 2 discloses a technique in which, based on 3D CAD data received from a 3D CAD device, a 3D CAM device performs interference checks between the workpiece and the entire machining system, including the NC machine, based on the 3D CAD data, before creating machining paths. This check is performed by a pre-machining analysis unit, specifically for checking the interference of the movement of jigs, tool holders, spindle heads, during table rotation, or during automatic tool changes. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] International Publication No. 2014 / 122995 [Patent Document 2] Japanese Patent Publication No. 2001-154715 [Overview of the project] [Problems that the invention aims to solve]

[0007] However, Patent Document 1 describes a technique for creating interference check models that uses geometric models, specifically combinations of spherical models, cylindrical models, and combinations of spherical and cylindrical models to create shapes, but it does not consider the coordinates of measurement points or the size of the three-dimensional coordinate measuring instrument. Furthermore, it does not consider how to determine whether measurement is possible or not.

[0008] Patent Document 2 describes the interference between the workpiece and the entire machining system, but it does not consider the coordinates of the measurement points. Furthermore, it does not consider how to determine whether measurement is possible or not.

[0009] It is desirable to determine the feasibility of dimensional measurement during the upstream design phase of manufacturing, and to reconsider and implement countermeasures for any parts that are difficult to measure during the design phase. This will prevent rework and additional considerations in the downstream manufacturing and quality assurance phases, thereby preventing process delays and increased measurement costs.

[0010] The object of the present invention is to provide a dimensional measurement management system and a dimensional measurement management method that can improve the economic efficiency of dimensional measurement. [Means for solving the problem]

[0011] The dimensional measurement management system of the present invention is characterized by comprising: a shape information extraction unit that extracts shape information to be measured from the design information of a target member; a measurement coordinate calculation unit that calculates measurement coordinates from the shape information extracted by the shape information extraction unit; a measurement area setting unit that sets a measurement area based on the measurement coordinates calculated by the measurement coordinate calculation unit and the dimensional information of a measuring instrument; an interference check unit that checks for interference by comparing the measurement area generated by the measurement area setting unit with the design information; and a measurement feasibility determination unit that determines whether measurement is possible or not based on the results of the interference check unit.

[0012] Alternatively, the dimensional measurement management method of the present invention is characterized by including: a shape information extraction step of extracting shape information to be measured from the design information of a target member; a measurement coordinate calculation step of calculating measurement coordinates from the shape information extracted in the shape information extraction step; a measurement area setting step of setting a measurement area based on the measurement coordinates calculated in the measurement coordinate calculation step and the dimensional information of a measuring instrument; an interference check step of comparing the measurement area generated in the measurement area setting step with the design information to check for interference; and a measurement feasibility determination step of determining whether measurement is possible or not based on the results of the interference check step. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a dimensional measurement management system and a dimensional measurement management method that can improve the economic efficiency of dimensional measurement. [Brief explanation of the drawing]

[0014] [Figure 1] This diagram shows the components for determining whether or not dimensional measurement is possible in the embodiment. [Figure 2] An example of design information is shown below. [Figure 3] This is a diagram showing a contact-type three-dimensional measuring machine. [Figure 4] It is an enlarged view of the tip portion of a contact three-dimensional measuring machine. [Figure 5] It is a diagram showing a hollow cylinder as an example of a target member. [Figure 6] It is a diagram showing measurement points of the hollow cylinder in the embodiment. [Figure 7] It is a diagram showing the contact probe of a contact three-dimensional measuring machine. [Figure 8] It is a detailed enlarged view of the tip portion of a contact three-dimensional measuring machine. [Figure 9] It is a diagram showing the position of the tip sphere of the contact probe in the embodiment. [Figure 10] It is a diagram showing the area where the tip sphere of the contact probe moves in the embodiment. [Figure 11] It is a diagram showing the state where the contact three-dimensional measuring machine of the embodiment is in contact with the measurement point. [Figure 12] It is a diagram explaining the collision (interference) between the target member and the contact three-dimensional measuring machine of the embodiment. [Figure 13] It is an explanatory diagram for avoiding interference between the target member and the contact three-dimensional measuring machine by optimizing the contact probe of the embodiment. [Figure 14] It is a diagram showing the state where the movable part of the contact three-dimensional measuring machine of the embodiment is represented in a simplified shape. [Figure 15] It is a diagram showing the state where the simplified shape of the movable part of the contact three-dimensional measuring machine in the embodiment is moved to the measurement point. [Figure 16] It is a diagram showing the approaching direction of the contact probe to the hollow cylinder in the embodiment. [Figure 17] It is a diagram showing the state where the hollow cylinder of the target member example and the measurement area in the embodiment are superimposed and displayed. [Figure 18] It is a diagram showing the state where the shape of the object to be measured and the measurement area in the embodiment are superimposed and displayed for interference confirmation.

Mode for Carrying Out the Invention

[0015] In embodiments of the present invention, the target member has a complex shape, and its contour and surface are understood at the design stage, and the feasibility of measurement is determined considering the size of the three-dimensional coordinate measuring instrument. The examples are illustrative for explaining the present invention, and have been omitted and simplified as appropriate for clarity of explanation. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be singular or plural. Furthermore, the position, size, shape, and range of each component shown in the drawings may not represent the actual position, size, shape, and range in order to facilitate understanding of the invention. For this reason, the present invention is not necessarily limited to the position, size, shape, and range disclosed in the drawings. Specific embodiments will be described below using Figures 1 to 18. [Examples]

[0016] Figure 1 shows the components for determining whether or not dimensional measurement is possible in this embodiment. In this embodiment, a contact-type three-dimensional measuring instrument is used as an example of the measuring instrument, but this embodiment is not limited to a contact-type three-dimensional measuring instrument.

[0017] As shown in Figure 1, the dimension measurement management system of this embodiment includes a shape information extraction unit 3 that extracts shape information to be measured from the design information 2 of the object to be measured, a measurement coordinate calculation unit 4 that calculates measurement coordinates from the extracted shape information, a measurement instrument dimension database 5 that records the dimension information of the measuring instrument, a measurement area setting unit 6 that sets a measurement area based on the measurement coordinates calculated by the measurement coordinate calculation unit 4 and the dimension information in the measurement instrument dimension database 5, an interference check unit 7 that compares the measurement area generated by the measurement area setting unit 6 with the object to be measured and performs an interference check, a measurement feasibility determination unit 8 that determines whether measurement is possible based on the results of the interference check unit 7, and a display unit 9 that displays the determination result from the measurement feasibility determination unit 8.

[0018] Designer 1 designs the target component and creates design information 2. Specific examples of design information 2 include data such as CAD drawings. For example, as shown in Figure 2, the center of the circle is 190 mm from one end of reference plane A and 300 mm from the other end of reference plane B, with a tolerance of φ0.1 mm. Such design information 2 is transmitted to the shape information extraction unit 3.

[0019] Next, in the shape information extraction step, the shape information extraction unit 3 extracts shape information of the contour and surface of the target member from the design information 2. A specific example of contour and surface shape information would be, for example, if the target member to be measured is a hollow cylinder 10 as shown in Figure 5, then it would be the inner surface 11. The information extracted by this shape information extraction unit 3 is sent to the measurement coordinate calculation unit 4. In this way, the shape information extraction unit 3 can grasp the contour and surface, which are the external shapes of the target member, based on the design information 2.

[0020] Next, in the measurement coordinate calculation step, the measurement coordinate calculation unit 4 calculates the measurement coordinates of the object to be measured from the extracted information. For convenience, this embodiment will be explained in two dimensions. For example, when measuring the diameter of the inner surface 11 of a hollow cylinder 10, as shown in Figure 6, the ball at the tip of the contact probe 106 is brought into contact with the inner surface 11 of the hollow cylinder 10 for measurement. This contact position becomes the measurement coordinate, but this information is not recorded in the CAD, which is the design information 2. Therefore, measurement points (coordinates) such as measurement points 201a to 201h, measurement points 202a to 202h, and measurement points 203a to 203h in Figure 6 are determined. In this example, measurements are performed on three cross-sections (201, 202, and 203) of the hollow cylinder.

[0021] In the example shown in Figure 6, the measurement points are evenly distributed at eight locations across the entire circumference. However, the measurement range may be limited to a 180-degree range, or the points may be unevenly distributed. The measurement coordinate information from the measurement coordinate calculation unit 4 is transmitted to the measurement area setting unit 6. In this way, the measurement coordinate calculation unit 4 can calculate the measurement coordinates of the object to be measured from the information extracted from the shape information extraction unit 3. The measurement coordinates may also be calculated using the functions of CAD.

[0022] Next, in the measurement area setting step, the measurement area setting unit 6 receives measurement coordinate information from the measurement coordinate calculation unit 4 and measurement equipment size information stored in the measurement equipment dimension database 5. Then, the measurement area setting unit 6 sets the measurement area based on the measurement coordinates calculated by the measurement coordinate calculation unit 4 and the dimension information from the measurement equipment dimension database 5.

[0023] The measuring instrument dimension database 5 stores dimensional information of measuring instruments, such as the dimensions of the contact probe, the dimensions of the holding part, and the dimensions of the movable part.

[0024] In the interference check step, the interference check unit 7 compares the measurement area generated by the measurement area setting unit 6 with the object to be measured to perform an interference check.

[0025] In the measurement feasibility determination step, the measurement feasibility determination unit 8 determines whether measurement is possible based on the results of the interference check unit 7. It also compares the measurement error with the tolerance of the measurement coordinates to determine whether measurement is possible or the number of measurement points. This allows for an appropriate and efficient determination of whether measurement is possible or the number of measurement points.

[0026] The display unit 9 displays the judgment result from the measurement feasibility determination unit 8. By checking this displayed information, the designer 1 can make various decisions.

[0027] By using the dimensional measurement and control methods described above, any parts that are difficult to measure can be re-examined and addressed during the design phase. This prevents rework and additional considerations in downstream manufacturing and quality assurance stages, thus preventing process delays and increased measurement costs. In short, it leads to improved economic efficiency throughout the entire process.

[0028] Figure 7 shows the general shape of the contact probe 106. D is the diameter of the probe sphere. These dimensions are listed in the contact probe catalog and should be stored in the instrument dimension database beforehand.

[0029] Figure 8 is a detailed enlarged view of the tip of a contact-type three-dimensional measuring machine. In other words, it is a detailed view of the tip structure 104 of the contact-type three-dimensional measuring instrument shown in Figures 3 and 4. As shown in Figure 3, the contact probe 106 is mounted on a skeleton, which is a holding part that holds the entire contact-type three-dimensional measuring instrument. The contact probe 106 has movable parts that move its direction and position. As an example of a movable part, it moves in the X direction with mechanism 101, in the Y direction with mechanism 102, and in the Z direction with mechanism 103. This brings it closer to the measurement point. It rotates around the Y axis with mechanism 108 and around the Z axis with mechanism 105, changing the orientation of the contact probe 106. There are also mechanisms that allow the orientation of the contact probe 106 to be freely changed, rather than just rotating on two axes. In order to take a measurement, it is necessary to ensure that the structure including this mechanism does not come into contact with the object to be measured. Here, the Z axis indicates the vertical direction, and in the water surface, it indicates the X and Y axes.

[0030] Figure 9 shows the position of the tip sphere of the contact probe in the embodiment. It shows the measurement points 204a to 204h set on the inner surface 11 of the hollow cylinder 10, and how the tip sphere of the contact probe 106 is in contact with each measurement point. The contact state is as shown in Figure 9.

[0031] Figure 10 shows the region in which the tip sphere of the contact probe moves in the embodiment. When the movement of the contact probe 106 is considered, the region occupied by the contact probe is as shown in region 205 in Figure 10. In addition to the contact probe 106, there is a movement mechanism as shown in Figure 8.

[0032] Figure 11 shows the contact-type three-dimensional measuring machine of the embodiment in contact with a measurement point. It shows the state of measuring the set measurement point 201a. On the other hand, Figure 12 shows the state of measuring the set measurement point 203a.

[0033] In Figure 12, the hollow cylinder 10 being measured and the moving mechanism of the three-dimensional measuring instrument are colliding (interfering). While it is also possible to approach from the opposite direction of the hollow cylinder 10, here we consider the situation shown in Figure 12 as an example of interference. As a way to avoid interference, as shown in Figure 13, one option is to use a longer probe 106a. If interference is known to occur, such avoidance measures can be considered. If information on the dimensions of the contact probe 106 is available, interference avoidance measures can be considered as described above. Similarly, if information on the dimensions of the holding and movable parts of the measuring device is available, interference avoidance measures can also be considered. This allows for the selection of a measuring device suitable for the object being measured.

[0034] While the actual shape may be used as the shape of the three-dimensional coordinate measuring instrument for interference checking, it may also be replaced with a simple geometric shape as shown in Figure 14. Figure 14 is a simplified example of a simplified shape 118, which is a combination of rectangular parallelepipeds that encloses the contact probe 106 and other moving mechanisms such as movable parts. The structure is simplified, but the main dimensions are based on the actual dimensions.

[0035] For interference checking, it is necessary to place a simplified shape at the measurement point, as shown in Figure 15. Figure 17 shows an example of how to place the simplified shape. In Figure 15, the simplified shape 118 is given the center coordinates 109, which are the coordinate information of the center of the probe sphere shown in Figure 7. The probe sphere is then positioned so that its center coordinates 109 are at a distance of radius D / 2 from the measurement point 203a.

[0036] This can be created by first preparing a simplified shape 118 consisting of a combination of rectangular prisms in CAD, assigning the center coordinates 109 of the probe sphere to it as described above, and then instructing the CAD system to draw the simplified shape 118 so that the center coordinates 109 of the probe sphere are located at a point D / 2 away from the measurement point 201a. It is also possible to create a list of the measurement point coordinates, load that list, and then process the system to draw the simplified shape 118 for each measurement point.

[0037] At this time, the angle of the contact probe can take on various angles depending on the settings of mechanisms 105 and 108 in Figure 8. This angle (orientation) may be set manually by the designer 1, but for example, as shown in Figure 16, a rule may be established to orient the contact probe 106 parallel to the axial direction n of the hollow cylinder 10, and the contact position may be determined automatically. In addition, a rule may be established to approach the contact probe 106 from the normal direction n201a to n201e of the inner surface 11 relative to the measurement point set on the inner surface 11, and the contact position may be determined automatically according to that rule.

[0038] In the interference check unit 7 of Figure 1, as shown in Figure 18, the shape of the object to be measured and the measurement area created by placing the simplified shape of Figure 14 at each measurement point are superimposed and displayed, for example, on a CAD system. Then, in the measurement feasibility determination unit 8 of Figure 1, if there are any overlapping areas, they are extracted using the interference confirmation function of the CAD system and displayed in the display unit 9, for example, by highlighting them (changing the drawing color).

[0039] As described above, according to this embodiment, by determining whether a predetermined measuring instrument can measure certain parts during the design phase of the upstream manufacturing process, it becomes possible to reconsider and take countermeasures during the design phase if there are parts that are difficult to measure. This prevents rework and additional considerations during the manufacturing and quality assurance phases of the downstream processes, thus preventing process delays and increased measurement costs. In other words, it leads to improved economic efficiency throughout the entire process. [Explanation of symbols]

[0040] 1...Designer, 2...Design information, 3...Information extraction unit, 4...Measurement coordinate calculation unit, 5...Measurement instrument dimension database, 6...Measurement area setting unit, 7...Interference check unit, 8...Measurement feasibility determination unit, 9...Output unit, 10...Hollow cylinder, 11...Inner surface, 100...Surface plate, 101...X-axis linear motion mechanism, 102...Y-axis linear motion mechanism, 103...Z-axis linear motion mechanism, 104...Tip of contact-type three-dimensional measuring instrument, 105...Rotation mechanism around the Z axis, 106...Contact probe, 107...Swing direction of contact probe, 108...Mechanism, 201a~201h, 202a~202h, 203a~203h...Measurement point, 109...Center coordinate, 204a~204h...Position of tip sphere of contact probe, 118...Simplified shape.

Claims

1. A shape information extraction unit extracts shape information to be measured from the design information of the target component, A measurement coordinate calculation unit calculates measurement coordinates from the shape information extracted by the shape information extraction unit, A measurement area setting unit sets a measurement area based on the measurement coordinates calculated by the measurement coordinate calculation unit and the dimensional information of the measuring instrument, An interference check unit compares the measurement area generated by the measurement area setting unit with the design information to perform interference checks, A dimension measurement management system characterized by having a measurement feasibility determination unit that determines whether measurement is possible or not based on the results of the interference check unit.

2. In the dimensional measurement management system according to claim 1, A dimension measurement management system characterized by having a measuring instrument dimension database that stores dimensional information of the measuring instrument and can transmit the dimensional information of the measuring instrument to the measurement area setting unit.

3. In the dimensional measurement management system according to claim 1, A dimensional measurement management system characterized in that the dimensional information of the measuring instrument includes the dimensions of the contact probe of the measuring instrument.

4. In the dimensional measurement management system according to claim 1, A dimensional measurement management system characterized in that the dimensional information of the measuring instrument includes the dimensions of the holding part of the measuring instrument.

5. In the dimensional measurement management system according to claim 1, A dimensional measurement management system characterized in that the dimensional information of the measuring instrument includes the dimensions of the movable parts of the measuring instrument.

6. In the dimensional measurement management system according to claim 1, A dimensional measurement management system characterized in that the shape information is the contour or surface of the target member to be measured.

7. In the dimensional measurement management system according to claim 1, The dimensional measurement management system is characterized in that the measurement feasibility determination unit compares the measurement error with the tolerance of the measurement coordinates to determine whether measurement is possible or the number of measurement points.

8. In the dimensional measurement management system according to claim 1, A dimensional measurement management system characterized in that the shape used in the measurement area setting unit is the actual shape of the measuring instrument.

9. In the dimensional measurement management system according to claim 1, A dimensional measurement management system characterized in that the shape used in the measurement area setting unit is a geometrically simplified shape of the actual shape of the measuring instrument.

10. A shape information extraction step that extracts shape information to be measured from the design information of the target component, A measurement coordinate calculation step which calculates measurement coordinates from the shape information extracted in the shape information extraction step, A measurement area setting step in which a measurement area is set based on the measurement coordinates calculated in the measurement coordinate calculation step and the dimensional information of the measuring instrument, An interference check step which compares the measurement area generated in the measurement area setting step with the design information to perform an interference check, A dimensional measurement management method characterized by including a measurement feasibility determination step that determines whether measurement is possible or not based on the results of the interference check step.

11. In the dimensional measurement control method according to claim 10, The dimensional measurement management method is characterized in that the measurement feasibility determination step includes comparing the measurement error with the tolerance of the measurement coordinates to determine whether measurement is possible or the number of measurement points.

Images