A method and device for automatic dimensioning

Abstract

The present invention proposes a method and device for automatic dimensioning, including: obtaining a three-dimensional model of an assembly for which a 2D drawing is required, traversing a structure tree to identify each part in the assembly, and marking each part; naming the connection surfaces of the marked parts; identifying the pin holes of the projection reference surface as reference holes for marking, and using the projection line of the connection surface where the reference holes are located as the reference edge of the reference holes; marking other holes according to the center axis of the reference holes in each 2D view, and the relative position relationship between other holes and the reference holes; marking according to the contour segments in the projection of each 2D view; marking according to the fillets and chamfers in the projection of each 2D view. The present invention simplifies the operation steps, can realize the dimensioning of parts in the view with one click, greatly reduces the workload of designers, and improves design efficiency.

Description

Technical Field

[0001] The invention belongs to the field of automated design, and in particular relates to a method and a device for automatic dimensioning. Background Art

[0002] Currently, when design companies process parts of designed fixtures, they need to export the three-dimensional model into a 2D drawing for mechanical processing. The dimensioning in the 2D drawing is particularly important, which is related to whether the part can be processed and its processing accuracy.

[0003] The traditional 2D drawing annotation steps are as follows: 1. Marking of reference holes: Determine the reference holes (pin holes) based on the assembly relationship of the parts, and mark the dimensions of the selected reference holes based on the connection relationship in the assembly.

[0004] 2. Marking of other hole positions: Use the center of the reference hole as the reference point to mark the center positions of other holes.

[0005] 3. Marking of the outer contour of parts: Mark the basic outline dimensions according to the shape of the parts.

[0006] 4. Final complete part marking: In the same view, mark the reference hole, other holes, and the outer contour dimensions of the part together, and arrange them reasonably to complete the design of the 2D part drawing of the corresponding part.

[0007] However, there are some defects in the traditional annotation steps, as follows: ① The designer needs to determine a pin hole as the marked reference hole based on the assembly relationship between the parts in the assembly.

[0008] ② Designers are required to manually draw two dimension lines for each dimension object.

[0009] ③ The overall dimension lines cannot overlap and the spacing must be reasonable. Designers need to manually move the annotation lines multiple times to move the annotations into place.

[0010] The above defects make the dimensioning operation more complicated for designers, resulting in heavy workload and low work efficiency. Summary of the invention

[0011] The present invention provides a method and device for automatic dimensioning, which simplifies the operation steps of dimensioning, reduces the workload of designers, and improves design efficiency.

[0012] To achieve the above object, the technical solution of the present invention is achieved as follows: A method for automatic dimensioning, comprising: S1. Obtain the 3D model of the assembly for which a 2D drawing is required, traverse the structure tree to identify each part in the assembly, and mark each part; S2. Name the connection surfaces of the marked parts; S3. Based on the named connection surface, identify the pin hole of the projection reference surface as the reference hole for marking, and use the projection line of the connection surface where the reference hole is located as the reference edge line of the reference hole; S4. marking other holes according to the center axis of the reference hole in each 2D view and the relative position relationship between other holes and the reference hole; S5. marking according to the contour line segments in the projection of each 2D view; S6. Mark the fillets and chamfers according to the projections of each 2D view.

[0013] Further, step S3 includes: The first connection surface of each part is used as a projection reference surface, and the pin hole is identified according to the attribute information and / or hole diameter of the part model.

[0014] Further, step S4 includes: The positioning dimensions of the reference hole are marked in a 2D view, and then the relative position relationship between other holes and the reference hole is marked through the center of the reference hole and the center axis of the reference hole in other 2D views, and then the diameters and processing requirements of the other holes are marked.

[0015] Further, step S5 includes: Segmented annotation is a line segment parallel to the X and Y axes of the 2D view. The annotation lines on the same side remain on the same straight line.

[0016] Further, step S6 includes: Annotate chamfers: Annotate the edges with the same distance from two common connection points to the intersection points of the two end segments among three adjacent line segments in the view; Annotate fillet: Select non-segment elements in the 2D view, measure the radius of the non-segment elements and annotate them.

[0017] Another aspect of the present invention further provides a device for automatic dimensioning, comprising: Parts identification module: obtain the 3D model of the assembly that needs a 2D drawing, traverse the structure tree to identify each part in the assembly, and mark each part; Connection surface naming module: name the connection surfaces of marked parts; Reference hole marking module: Based on the named connection surface, the pin hole on the projection reference surface is identified as the reference hole for marking, and the projection line of the connection surface where the reference hole is located is used as the reference edge line of the reference hole; Other hole marking module: marking other holes according to the center axis of the reference hole in each 2D view and the relative position relationship between other holes and the reference hole; Outer contour annotation module: Annotate according to the contour segments in the projection of each 2D view; Fillet and chamfer annotation module: Annotate fillets and chamfers according to the projection of each 2D view.

[0018] Furthermore, the reference hole annotation module includes: The first connection surface of each part is used as a projection reference surface, and the pin hole is identified according to the attribute information and / or hole diameter of the part model.

[0019] Furthermore, other hole annotation modules include: The positioning dimensions of the reference hole are marked in a 2D view, and then the relative position relationship between other holes and the reference hole is marked through the center of the reference hole and the center axis of the reference hole in other 2D views, and then the diameters and processing requirements of the other holes are marked.

[0020] Furthermore, the outer contour annotation module includes: First, mark the line segments parallel to the X-axis and Y-axis of the 2D view in sections, and keep the marking lines on the same side on the same straight line.

[0021] Furthermore, the fillet and chamfer annotation module includes: Annotate chamfer units: Annotate the edges with the same distance from the intersection points of the two common connection points of three adjacent line segments in the view; Annotate fillet elements: Select non-segment elements in the 2D view, measure the radius of the non-segment elements and annotate them.

[0022] Compared with the prior art, the present invention has the following beneficial effects: The present invention simplifies the operation steps and can realize the dimensioning of parts in the view with one key, which greatly reduces the workload of designers and improves design efficiency.

[0023] The present invention automatically confirms the marked reference holes in the part view by automatically identifying the part, its connecting surface and the pin holes on the connecting surface, without the need for designers to identify the reference holes one by one according to the model of the assembly.

[0024] The present invention can automatically identify line segments in a view as annotation objects and automatically annotate them, without the need for designers to annotate the line segments one by one.

[0025] The present invention can automatically adjust the distance and position of the marked dimension line according to the set standard, and the designer does not need to move the position of the manually marked dimension. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the process of the present invention; Figure 2 is a schematic diagram of the execution logic of the automatic labeling of Embodiment 1 of the present invention; Figure 3 is a schematic diagram of parts marking of embodiment 1 of the present invention; Figure 4 This is a schematic diagram of connection surface naming in Example 1 of the present invention; Figure 5 is a schematic diagram of a pin hole for attribute determination according to Embodiment 1 of the present invention; Figure 6 is a schematic diagram of a pin hole for determining the aperture in Embodiment 1 of the present invention; Figure 7 is a schematic diagram of chamfer marking of embodiment 1 of the present invention; Figure 8 is a schematic diagram of rounded corner marking in Example 1 of the present invention; Fig. 9 It is a schematic diagram of the device structure of Example 2 of the present invention. DETAILED DESCRIPTION

[0027] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0028] The automatic dimensioning method proposed by the present invention is as follows: Figure 1 As shown, including: S1. Obtain the 3D model of the assembly for which a 2D drawing is required, traverse the structure tree to identify each part in the assembly, and mark each part; S2. Name the connection surfaces of the marked parts; S3. Based on the named connection surface, identify the pin hole of the projection reference surface as the reference hole for marking, and use the projection line of the connection surface where the reference hole is located as the reference edge line of the reference hole; S4. marking other holes according to the center axis of the reference hole in each 2D view and the relative position relationship between other holes and the reference hole; S5. marking according to the contour line segments in the projection of each 2D view; S6. Mark the fillets and chamfers according to the projections of each 2D view.

[0029] Based on the above method, the present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0030] Embodiment 1:

[0031] In this embodiment, the design software takes Catia as an example, develops an automatic marking function software, calls the Catia interface, and realizes automatic marking. The specific execution logic is as follows: Figure 2 As shown, including: 1. The functional software calls the interface of Catia through a function to obtain the assembly model that needs to produce a 2D drawing. The functional software traverses the structure tree, identifies each part in the assembly, and marks each part, such as Figure 3 As shown, they can be named as the first connecting member, the second connecting member, the third connecting member, etc. as needed.

[0032] Second, the mounting surfaces on the parts are named, and they can be named as the first connection surface, the second connection surface, the third connection surface, etc. according to the part numbers. The specific naming method in this embodiment is as follows: When the first connecting member has a connecting surface, the surface on the first connecting member where the first connecting surface is connected and installed with the corresponding surface of the second connecting member is named the first connecting surface of the second connecting member; the corresponding installation surface on the second connecting member with other connecting members (such as the third connecting member) is the second connecting surface corresponding to the other connecting member (such as the third connecting member), and the first connecting surface on the other connecting member (such as the third connecting member) is the second connecting surface on the second connecting member corresponding to the present connecting member, and so on.

[0033] If a connector, such as the first connector, has multiple connecting surfaces, measure the area of ​​the part plane where the connecting surfaces are located, and the part plane with the largest area is named the first connecting surface on the first connector. The remaining connecting surfaces are the second connecting surfaces, and the connecting surfaces of other connectors corresponding to the second connecting surfaces are the first connecting surfaces of the other connectors, and so on.

[0034] like Figure 4 As shown, if the first connector and the second connector have corresponding connection surfaces, the corresponding connection surface of the first connector is the first connection surface of the first connector, and the corresponding connection surface of the second connector is the first connection surface of the second connector. The second connector also has connection surfaces with the 3.1 connector and the 3.2 connector, respectively. Then the connection surface between the second connector and the 3.1 connector is named the 2.1 connection surface, and the connection surface between the second connector and the 3.2 connector is named the 2.2 connection surface; and the surface of the 3.1 connector corresponding to the 2.1 connection surface on the second connector is named the first connection surface of the 3.1 connector, and the surface of the 3.2 connector corresponding to the 2.2 connection surface on the second connector is named the first connection surface of the 3.2 connector.

[0035] 3. Determination of the marked reference holes on the connection surfaces of parts.

[0036] Use the first connection surface of the named part as the projection reference surface of the part, identify the pin holes on the projection reference surface, and any pin hole can be used as the marked reference hole. Since the connection surfaces are all finished surfaces, the projection line of the finished surface is used as the reference edge line of the reference hole during marking.

[0037] The pin hole identification method includes: the type of hole can be determined according to the properties of the part model, for example Figure 5 The name, color, etc. shown can also be used to determine whether it is a pin hole based on the hole diameter, such as Figure 6 The standard pin sizes are shown. Based on this size list, the corresponding hole diameter can be determined as a pin hole.

[0038] 4. In each 2D view, according to the center axis of the reference hole in the 2D view, mark the dimensions of the center of other holes in each 2D view projection to the center axis of the reference hole. The marking logic is to mark the positioning dimension of the reference hole in a certain 2D view, and then mark the relative position relationship between other holes and the reference hole through the center of the reference hole and the center axis of the reference hole in other 2D views. The marked dimension value is measured from the projection view; then mark the diameter of the hole and the processing requirements.

[0039] 5. After the reference hole marking is completed, first mark the line segments parallel to the X-axis and Y-axis of the 2D view in sections according to the contour segments in the projection of each 2D view. The marking lines on the same side must be kept on the same straight line.

[0040] 6. Chamfer and fillet annotation: The chamfer annotation method includes: annotating the edges with the same distance from two common connection points of three adjacent line segments in the 2D view to the intersection point of the two end segments, or annotating the distance from the intersection point of the two end segments of the three adjacent line segments in the 2D view to the two end points of the three line segments, such as Figure 7 shown.

[0041] The fillet annotation method includes: identifying all non-straight line elements in each 2D view, measuring their radius, and then annotating them, such as Figure 8 shown.

[0042] In the execution logic of automatic annotation in this embodiment, dimension annotation of drawings in 2D views is realized through the key technology of dimension annotation, and the key technology is: dimension annotation CATIDrwDimTolerance->SetLabel(); creating the annotation object CATIDrwAnnotationFactory class.

[0043] At the same time, the software design has the following interface implementation object annotations.

[0044] Model picking: SelectPart(); Parameter acquisition: GetParameter(); Parameter update: SetParameter(); 2D object acquisition: Get2DLine(); Get size object: GetSizeLine(); Special symbol marking: SetNumeric(); Dimension tolerance annotation: SetTolerance(); Text annotation: SetText(); Roughness annotation: SetRoughness().

[0045] Compared with the prior art, the method described in this embodiment simplifies the operation steps and can realize the dimensioning of parts in the view with one click, which greatly reduces the workload of designers and improves design efficiency.

[0046] Embodiment 2:

[0047] Example 2 proposes a device for automatic dimensioning, such as Fig. 9 As shown, including: Parts identification module: obtain the 3D model of the assembly that needs a 2D drawing, traverse the structure tree to identify each part in the assembly, and mark each part; Connection surface naming module: name the connection surfaces of marked parts; Reference hole marking module: Based on the named connection surface, the pin hole on the projection reference surface is identified as the reference hole for marking, and the projection line of the connection surface where the reference hole is located is used as the reference edge line of the reference hole; Other hole marking module: marking other holes according to the center axis of the reference hole in each 2D view and the relative position relationship between other holes and the reference hole; Outer contour annotation module: Annotate according to the contour segments in the projection of each 2D view; Fillet and chamfer annotation module: Annotate fillets and chamfers according to the projection of each 2D view.

[0048] Among them, the reference hole annotation module includes: The first connection surface of each part is used as a projection reference surface, and the pin hole is identified according to the attribute information and / or hole diameter of the part model; Other hole callout modules include: The positioning dimensions of the reference hole are marked in a 2D view, and then the relative position relationship between other holes and the reference hole is marked through the center of the reference hole and the center axis of the reference hole in other 2D views, and then the diameters and processing requirements of the other holes are marked.

[0049] The contour annotation module includes: First, mark the line segments parallel to the X-axis and Y-axis of the 2D view in sections, and keep the marking lines on the same side on the same straight line.

[0050] The fillet and chamfer annotation module includes: Annotate chamfer units: Annotate the edges with the same distance from the intersection points of the two common connection points of three adjacent line segments in the view; Annotate fillet elements: Select non-segment elements in the 2D view, measure the radius of the non-segment elements and annotate them.

[0051] The device proposed in this embodiment 2 can implement the method of automatic dimensioning described in embodiment 1, and has the same technical effect as the method described in embodiment 1.

[0052] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for automatic dimensioning, characterized in that: include: S1. Obtain the 3D model of the assembly for which a 2D drawing is required, traverse the structure tree to identify each part in the assembly, and mark each part; S2. Name the connection surfaces of the marked parts; S3. Based on the named connection surface, identify the pin hole of the projection reference surface as the reference hole for marking, and use the projection line of the connection surface where the reference hole is located as the reference edge line of the reference hole; S4. marking other holes according to the center axis of the reference hole in each 2D view and the relative position relationship between other holes and the reference hole; S5. marking according to the contour line segments in the projection of each 2D view; S6. Mark the fillets and chamfers according to the projections of each 2D view.

2. The method for automatic dimensioning according to claim 1, characterized in that: Step S3 includes: The first connection surface of each part is used as a projection reference surface, and the pin hole is identified according to the attribute information and / or hole diameter of the part model.

3. The method for automatic dimensioning according to claim 1, characterized in that: Step S4 includes: The positioning dimensions of the reference hole are marked in a 2D view, and then the relative position relationship between other holes and the reference hole is marked through the center of the reference hole and the center axis of the reference hole in other 2D views, and then the diameters and processing requirements of the other holes are marked.

4. The method for automatic dimensioning according to claim 1, characterized in that: Step S5 includes: Segmented annotation is a line segment parallel to the X and Y axes of the 2D view. The annotation lines on the same side remain on the same straight line.

5. The method for automatic dimensioning according to claim 1, characterized in that: Step S6 includes: Annotate chamfers: Annotate the edges with the same distance from two common connection points to the intersection points of the two end segments among three adjacent line segments in the view; Annotate fillet: Select non-segment elements in the 2D view, measure the radius of the non-segment elements and annotate them.

6. A device for automatic dimensioning, characterized in that: include: Parts identification module: obtain the 3D model of the assembly that needs a 2D drawing, traverse the structure tree to identify each part in the assembly, and mark each part; Connection surface naming module: name the connection surfaces of marked parts; Reference hole marking module: Based on the named connection surface, the pin hole on the projection reference surface is identified as the reference hole for marking, and the projection line of the connection surface where the reference hole is located is used as the reference edge line of the reference hole; Other hole marking module: marking other holes according to the center axis of the reference hole in each 2D view and the relative position relationship between other holes and the reference hole; Outer contour annotation module: Annotate according to the contour segments in the projection of each 2D view; Fillet and chamfer annotation module: Annotate fillets and chamfers according to the projection of each 2D view.

7. The automatic dimensioning device according to claim 6, characterized in that: The datum hole annotation module includes: The first connection surface of each part is used as a projection reference surface, and the pin hole is identified according to the attribute information and / or hole diameter of the part model.

8. The automatic dimensioning device according to claim 6, characterized in that: Other hole callout modules include: The positioning dimensions of the reference hole are marked in a 2D view, and then the relative position relationship between other holes and the reference hole is marked through the center of the reference hole and the center axis of the reference hole in other 2D views, and then the diameters and processing requirements of the other holes are marked.

9. The automatic dimensioning device according to claim 6, characterized in that: The contour annotation module includes: First, mark the line segments parallel to the X-axis and Y-axis of the 2D view in sections, and keep the marking lines on the same side on the same straight line.

10. The automatic dimensioning device according to claim 6, characterized in that: The fillet and chamfer annotation module includes: Annotate chamfer units: Annotate the edges with the same distance from the intersection points of the two common connection points of three adjacent line segments in the view; Annotate fillet elements: Select non-segment elements in the 2D view, measure the radius of the non-segment elements and annotate them.

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