Machining program generation device, numerical control device, machining system, and machining program generation method

Abstract

This machining program generation device comprises: an acquisition unit that acquires tool data, machining information indicating a machining method for turning that defines an operation of a tool, raw material shape data indicating the shape of an object to be machined, and product shape data indicating the shape of a product; an extraction unit that extracts, on the basis of the tool data, the machining information, the raw material shape data, and the product shape data, first shape data indicating the uncut shape left uncut in the turning; an uncut shape correction unit (26) that corrects the first shape data on the basis of the tool data so as to include an uncut portion caused by the curvature of a cutting edge of the tool, and generates second shape data; and a generation unit that generates, on the basis of the second shape data, a machining program for executing turning so as to include a machining step for turning the uncut shape.

Description

Processing Program Generation Device, Numerical Control Device, Machining System, and Processing Program Generation Method

[0001] The present disclosure relates to a processing program generation device, a numerical control device, a machining system, and a processing program generation method for generating a processing program for turning.

[0002] In cutting, one of the workpiece, which is the object to be processed, and the cutting tool is rotated at high speed, and the cutting tool and the workpiece are brought into contact to perform the processing. For example, in turning, which is a type of cutting, a turning tool called a tool bit is pressed against the workpiece that is rotated at high speed to perform the processing.

[0003] In the processing of forming a concave portion in the workpiece, there may be a portion that is not hit by the turning tool and remains uncut on the workpiece.

[0004] Patent Document 1 discloses a cutting tool generation unit that generates a tool shape capable of cutting the uncut portion of the concave portion from the uncut shape when there is no tool capable of cutting the uncut portion of the concave portion in a tool registered in advance, and creates numerical control information for the concave shape by the generated tool.

[0005] Japanese Patent No. 2599206

[0006] Since turning is a cross-feed machining in one direction, depending on the shape of the machining part and the tool shape, uncut portions may occur. However, in the technique disclosed in Patent Document 1, although a tool shape capable of cutting the uncut portion of the concave portion is generated from the uncut shape and numerical control information for the concave shape by the generated tool is created, a machining program including a machining process capable of eliminating the uncut portion in consideration of the shape of the tool edge and the uncut shape is not generated, and there is a problem that the uncut portion cannot be easily and accurately eliminated.

[0007] The present disclosure has been made in view of the above, and an object thereof is to obtain a processing program generation device capable of generating a processing program that can perform turning while easily and accurately eliminating uncut portions.

[0008] To solve the above-mentioned problems and achieve the objective, the machining program generation device according to this disclosure includes an acquisition unit that acquires tool data including information on the tool and turning conditions used for turning on a workpiece, machining information indicating a turning method that defines the operation of the tool, material shape data indicating the shape of the workpiece, and product shape data indicating the shape of the product, and an extraction unit that extracts first shape data indicating the uncut shape, which is the shape left uncut during turning, based on the tool data, machining information, material shape data, and product shape data. The machining program generation device includes an uncut shape correction unit that corrects the first shape data extracted by the extraction unit based on the tool data so as to include the uncut shape caused by the curvature of the cutting edge of the tool, and generates second shape data, and a generation unit that generates a machining program for performing turning, which includes a machining step of turning the uncut shape, based on the second shape data.

[0009] The machining program generation device described herein has the effect of being able to generate a machining program that enables turning while easily and accurately eliminating uncut material.

[0010] A figure showing the configuration of the machining system according to Embodiment 1. A figure showing an example of the specifications of a cutting tool stored in the tool data storage unit of the machining program generation device according to Embodiment 1. A flowchart showing the procedure of the machining program generation process performed by the machining program generation device according to Embodiment 1. A figure showing an example of a product shape corresponding to the product shape data stored in the shape data storage unit of the machining program generation device according to Embodiment 1. A figure showing an example of a material shape corresponding to the material shape data stored in the shape data storage unit of the machining program generation device according to Embodiment 1. The shape arrangement unit of the machining program generation device according to Embodiment 1 arranges the shape.Figure showing an example of product shape data and material shape data. Schematic diagram showing an example of turning shape data generated by the turning program generation unit of the processing program generation device according to Embodiment 1. Schematic diagram showing an example of turning shape data generated by the turning program generation unit of the processing program generation device according to Embodiment 1. Figure showing an example of a list of processing steps for a processing program generated by the turning program generation unit and the remaining material processing program generation unit of the processing program generation device according to Embodiment 1. Block diagram showing the configuration of the remaining material processing program generation unit according to Embodiment 1. Flowchart showing the detailed procedure for generating the remaining material processing program performed by the remaining material processing program generation unit of the processing program generation device according to Embodiment 1. Flowchart showing the detailed procedure for generating the remaining material shape performed by the remaining material processing program generation unit of the processing program generation device according to Embodiment 1. A diagram showing an example of the process of generating a remaining material shape from a machined shape in the remaining material machining program generation unit of the machining program generation device according to Embodiment 1. A diagram showing an example of the process of generating a remaining material shape from a machined shape in the remaining material machining program generation unit of the machining program generation device according to Embodiment 1. A diagram showing an example of the process of generating a remaining material shape from a machined shape in the remaining material machining program generation unit of the machining program generation device according to Embodiment 1. A diagram showing an example of the process of generating a remaining material shape from a machined shape in the remaining material machining program generation unit of the machining program generation device according to Embodiment 1. A diagram showing an example of the process of generating a remaining material shape from a machined shape in the remaining material machining program generation unit of the machining program generation device according to Embodiment 1. The remaining material machining program generation unit of the machining program generation device according to Embodiment 1 performs the following:A flowchart showing the detailed procedure for generating a machining program for the remaining material shape. A figure showing an example of the remaining material shape corrected by the remaining material shape correction unit of the machining program generation device according to Embodiment 1, in accordance with the radius value of the cutting edge R. A flowchart showing the detailed procedure for tool selection performed by the tool selection unit of the machining program generation device according to Embodiment 1. A figure showing an example of the maximum cutting edge angle obtained from the turning shape by the machining program generation device according to Embodiment 1. A figure showing an example of the maximum cutting edge angle obtained from the turning shape by the machining program generation device according to Embodiment 1. A figure showing an example of the maximum cutting edge angle obtained from the turning shape by the machining program generation device according to Embodiment 1. A block diagram showing the hardware configuration of the machining program generation device according to Embodiment 1.

[0011] The machining program generation apparatus, numerical control device, machining system, and machining program generation method according to the embodiment will be described in detail below with reference to the drawings.

[0012] Embodiment 1. Figure 1 is a diagram showing the configuration of a machining system according to Embodiment 1. The machining system 200 comprises a machine tool 60 that performs turning on a workpiece and a numerical control device 100 that numerically controls the machine tool 60 using a machining program 2.

[0013] The machine tool 60 is a lathe or a multi-tasking lathe. In other words, the following description will explain the case in which machining is performed by pressing a cutting tool, which is used for turning, against a workpiece that is rotating at high speed.

[0014] The numerical control device 100 automatically creates a machining program 2 for numerically controlling the machine tool 60, and controls the machine tool 60 using the created machining program 2. Here, the machining program 2 is used to machine a workpiece from its raw material state to cut out the shape of the turned product.

[0015] The numerical control device 100 includes a processing program generation device 10, an interactive operation processing unit 20, an instruction input unit 30, a display unit 40, and a control unit 50.

[0016] The machining program generation device 10 is a device that generates a machining program 2 which includes multiple turning processes for machining a turned product from a workpiece using numerical control. The machining program generation device 10 generates the machining program 2 based on machining shape data input to the machining program generation device 10 from outside the numerical control device 100. The machining shape data includes material shape data and product shape data. The machining program generation device 10 of Embodiment 1 generates the machining program 2 based on shape-corrected product shape data and material shape data.

[0017] Material shape data defines the material shape, which is the shape of the workpiece before processing. Product shape data defines the product shape, which is the shape of the workpiece after processing. Material shape data and product shape data are, for example, CAD (Computer-Aided Design) data 1.

[0018] The machining program generation device 10 generates a machining program 2, which includes machining unit information, based on the placement positions of the material shape data and product shape data, the workpiece origin, and the program coordinates. The machining program 2 includes a turning program 2a and a remaining material machining program 2b, which will be described later.

[0019] A machining unit represents machining performed continuously on the same spindle using the same tool. Machining unit information includes machining information that specifies the turning method defining the tool's movement, tool data that includes information on the tool used for machining and turning conditions, and shape sequence data that includes shape information defining a machining shape consisting of a single shape. Machining unit information is also data for machining processes such as turning units, stepped hole machining units, surface machining units, R-chamfering units, and C-chamfering units. A turning unit is a machining unit in which turning is performed, a stepped hole machining unit is a machining unit in which stepped holes are machined, a surface machining unit is a machining unit in which surface machining is performed, an R-chamfering unit is a machining unit in which R-chamfering is performed, and a C-chamfering unit is a machining unit in which C-chamfering is performed. Note that the shape information defining the machining shape may include information such as the surface roughness of the workpiece.

[0020] The tool information includes the type and shape of the tool. The tool information may also include information about the tool holder. The tool holder information includes the type and shape of the tool holder. The turning conditions are the turning speed, rotational speed, and feed rate used by the machine tool 60 during machining.

[0021] The interactive operation processing unit 20 serves as an interface between the numerical control device 100 and the operator, as well as an interface between the processing program generation device 10 and the operator. The interactive operation processing unit 20 transmits the instruction information entered by the operator via the instruction input unit 30 to the processing program generation device 10. The interactive operation processing unit 20 also displays the instruction information entered by the operator via the instruction input unit 30 on the display unit 40.

[0022] The instruction input unit 30 consists of input devices such as a mouse and a keyboard. The instruction input unit 30 receives instruction information from the operator and transmits the instruction information to the interactive operation processing unit 20.

[0023] The display unit 40 is a display device such as an LCD monitor, and displays CAD data 1, processing program 2, and instruction information entered by the operator via the instruction input unit 30. The display unit 40 can also display various information related to the processing performed by the numerical control device 100 and the processing program generation device 10.

[0024] The control unit 50 controls the machine tool 60 using the machining program 2 generated by the machining program generation device 10.

[0025] The machining program generation device 10 includes a shape input unit 11, a shape data storage unit 12, a shape arrangement unit 13, a tool data storage unit 14, a tool selection unit 15, a turning program generation unit 16, and a remaining material machining program generation unit 17.

[0026] Assembly data, product shape data, and material shape data are input from an external device of the numerical control device 100 to the processing program generation device 10. The assembly data, product shape data, and material shape data are composed of CAD data 1. The assembly data is composed of multiple combinations of at least one of the product shape data and material shape data.

[0027] The shape input unit 11 receives CAD data 1 input from an external device. The product shape data and material shape data are not limited to CAD data 1, but can be any data that the processing program generation device 10 can interpret.

[0028] The shape data storage unit 12 stores product shape data input to the shape input unit 11. The product shape data includes product shape data, which is the finished shape of the turned product, and material information indicating the material of the workpiece. The shape data storage unit 12 also stores material shape data input to the shape input unit 11. The material shape data is data of the material shape, which is the shape of the workpiece before processing. Examples of material shapes include cylindrical or rectangular parallelepiped shapes that enclose the product shape. Furthermore, the material shape does not necessarily have to enclose the product shape; it may be a shape with any face of the product shape thickened, or a shape with holes removed from the product shape. The material shape data may also include material information indicating the material of the material.

[0029] The shape arrangement unit 13 arranges the product shape data, material shape data, work origin, and program coordinate system stored in the shape data storage unit 12. The shape arrangement unit 13 may arrange the material shape and product shape so that the material shape encloses the product shape, or so that a part of the product shape overlaps the material shape. The product shape data and material shape data are stored in the shape data storage unit 12 along with the arrangement data. The shape arrangement unit 13 also places the work origin, which serves as the basis for generating the machining program, at the center position of the end face of the product shape data. Furthermore, the shape arrangement unit 13 arranges the program coordinate system, which serves as the basis for generating the machining program, so that the Z-axis of the program coordinate system coincides with the central axis of the cylindrical, conical, or annular surface of the product shape data that is turned. The work origin and program coordinate system are stored in the shape data storage unit 12 along with the arrangement data.

[0030] The tool data storage unit 14 stores tool data that associates the type of tool with the shape of the tool. Turning tools, or cutting tools, include internal diameter tools, external diameter tools, and grooving tools, parting tools, and threading tools depending on the machining application. Figure 2 shows an example of the specifications of a cutting tool stored in the tool data storage unit of the machining program generation device according to Embodiment 1. Parameters indicating the shape of the cutting tool 151 include the cutting edge radius R, the cutting edge angle, the cutting edge angle, and the secondary cutting edge angle. The cutting edge radius is sometimes called the nose radius.

[0031] The tool selection unit 15 selects the tool to be used for machining based on the tool data stored in the tool data storage unit 14 when the turning program generation unit 16 and the remaining material machining program generation unit 17 each generate the turning program 2a and the remaining material machining program 2b, respectively.

[0032] The turning program generation unit 16 generates a turning program 2a based on the product shape data, material shape data, workpiece origin, and program coordinate system stored in the shape data storage unit 12.

[0033] The remaining material machining program generation unit 17 generates a remaining material machining program 2b based on the product shape data stored in the shape data storage unit 12, the tool data stored in the tool data storage unit 14, and the turning program 2a generated by the turning program generation unit 16.

[0034] Next, the operation of the numerical control device 100 will be described. The operation of the numerical control device 100 includes the machining program generation process performed by the machining program generation device 10.

[0035] Figure 3 is a flowchart illustrating the procedure for generating a processing program performed by the processing program generation apparatus according to Embodiment 1. In step S1, the shape input unit 11 reads CAD data 1 of the product shape from a storage area (not shown) and stores the CAD data 1 of the product shape as product shape data in the shape data storage unit 12. In step S2, the shape input unit 11 generates a material shape based on the product shape data stored in the shape data storage unit 12 and stores it as material shape data. If the shape input unit 11 reads CAD data 1 of the material shape from a storage area (not shown), the shape data storage unit 12 stores the CAD data 1 of the material shape read by the shape input unit 11 as material shape data.

[0036] Figure 4 is a diagram showing an example of a product shape corresponding to the product shape data stored in the shape data storage unit of the processing program generation device according to Embodiment 1. Figure 5 is a diagram showing an example of a material shape corresponding to the material shape data stored in the shape data storage unit of the processing program generation device according to Embodiment 1. In Figure 4, product shape SA1 is shown as an example of a product shape, and in Figure 5, material shape SB2 is shown as an example of a material shape.

[0037] In step S3, the shape placement unit 13 places the product shape and the material shape, respectively. That is, in step S3, the shape placement unit 13 first generates placement data for the product shape and the material shape. In other words, the shape placement unit 13 generates placement data indicating the placement positions of the product shape and the material shape.

[0038] Next, the shape placement unit 13 places the product shape data and material shape data based on the generated placement data. At least one of the product shape data and material shape data may be placed at any position by the operator using the interactive operation processing unit 20, the instruction input unit 30, and the display unit 40.

[0039] In step S4, the shape placement unit 13 sets the work origin and program coordinate system at an arbitrary position from either the placed product shape or material shape, and stores the coordinate values ​​of the work origin and the direction vectors of each axis of the program coordinates. The work origin and program coordinate system may be placed at any position and in any direction by the operator using the interactive operation processing unit 20, the instruction input unit 30, and the display unit 40. If the coordinate values ​​of the work origin and the direction vectors of each axis of the program coordinates are set to the world coordinate system, this step can be omitted.

[0040] Figure 6 shows an example of product shape data and material shape data arranged by the shape arrangement unit of the machining program generation apparatus according to Embodiment 1. In Figure 6, product shape SA1, which is an example of a shape shown in the product shape data, material shape SB2, which is an example of a shape shown in the material shape data, and program coordinate system AX3 are shown. Note that the turning spindle is not shown in Figure 6.

[0041] The product is formed by turning the material. Therefore, Figure 6 shows the case where the product shape SA1 is positioned inside the material shape SB2.

[0042] In step S5, the turning program generation unit 16 unfolds the turning shape that indicates the area to be machined. Specifically, the turning program generation unit 16 generates machining shape data from the product shape data, material shape data, workpiece origin, and program coordinate system stored in the shape data storage unit 12. Furthermore, the turning program generation unit 16 generates turning shape data from the machining shape data. The machining shape corresponds to the shape of the difference between the product shape data and the material shape data. The machining shape data is data of the area to be machined relative to the material. The turning shape data is data indicating the area to be turned.

[0043] Next, the turning program generation unit 16 assigns a processing unit to the developed turning shape. That is, the turning program generation unit 16 determines a processing method, tool data, and turning conditions for the generated turning shape. The turning program generation unit 16 generates machining unit information for turning by assigning information on the machining method, tool, and turning conditions to the turning shape. Thus, the turning program generation unit 16 generates the turning program 2a by assigning a processing unit to the developed turning shape and generating machining unit information.

[0044] In step S6, the remaining machining program generation unit 17 generates a remaining shape based on the generated machining unit information for turning, machining information, tool data, and the machining shape. Specifically, the remaining machining program generation unit 17 generates an actual machining shape that is actually machined from the machining unit information, the machining shape, and the tool data, and calculates the difference obtained by subtracting the actual machining shape from the machining shape, thereby generating the remaining shape.

[0045] Furthermore, the remaining machining program generation unit 17 corrects the generated remaining shape so as to include the remaining due to the cutting edge R of the tool data. Specifically, the remaining shape generated due to the cutting edge angle caused by the movement of the tool is enlarged so that the remaining shape generated due to the cutting edge R of the tool is included, thereby correcting the generated remaining shape so as to include the remaining due to the cutting edge R.

[0046] Next, the remaining machining program generation unit 17 assigns a processing unit that combines a turning groove machining unit, a turning machining unit that turns in the opposite direction to the original turning machining unit, or a turning machining unit that turns in the opposite direction to the original turning machining unit and the turning groove machining unit to the corrected remaining shape. That is, the remaining machining program generation unit 17 determines a processing method, tool data, and turning conditions for the generated remaining shape.

[0047] The roughing process program generation unit 17 generates machining unit information for turning by assigning information on the machining method, tool, and turning conditions to the roughing shape, and generates a roughing process program 2b.

[0048] As described above, the machining program generation device 10 ends the machining program generation process according to the procedure shown in FIG. 3.

[0049] FIGS. 7 and 8 are schematic diagrams showing an example of turning shape data generated by the turning program generation unit of the machining program generation device according to the first embodiment. In FIG. 7, a turning hole machining shape SH1, which is an example of the shape shown by the turning shape data in the front side process, and turning shapes SH2, SH3, SH4, and SH5 are schematically shown. In FIG. 8, turning hole machining shapes SH6, SH7, and SH8, which are examples of the shapes shown by the turning shape data in the back side process, are schematically shown. The process of the turning program generation unit 16 generating the turning program 2a and the process of the roughing process program generation unit 17 generating the roughing process program 2b correspond to the processes of steps S5 and S6 in FIG. 3.

[0050] FIG. 9 is a diagram showing an example of a machining process list of the machining program generated by the turning program generation unit and the roughing process program generation unit of the machining program generation device according to the first embodiment. In the front side machining process HD1 of the machining program 2, machining units Uno1. to Uno5. are included. Also, in the back side machining process HD2 of the machining program 2, machining units Uno. 6. to Uno. 8 are included.

[0051] "Uno1. Turning Drill...SH1" indicates that the turning hole machining shape SH1 will be machined as a turning drill unit. "Uno2. End Face...SH2" indicates that the turning machining shape SH2 will be machined as a turning end face unit. "Uno3. Bar Stock...SH3", "Uno4. Bar Stock...SH4", and "Uno5. Bar Stock...SH5" indicate that the turning machining shapes SH3, SH4, and SH5 will be machined as turning bar stock units. Of these, "Uno4. Bar Stock...SH4" is a residual machining program 2b that processes the residual material left over from "Uno3. Bar Stock...SH3" using a tool with a cutting edge angle of 100 degrees, a secondary cutting edge angle of 55 degrees, and a cutting edge radius of R1, and is generated by the process in step S6 of Figure 3. Note that Uno1. to Uno5. Next, the material is held on the first spindle side and machined from the front.

[0052] "Uno 6. End face...SH6" indicates that the turned hole machining shape SH6 is machined as a turned end face unit. "Uno 7. Bar stock...SH7" and "Uno 8. Bar stock...SH8" indicate that the turned hole machining shapes SH7 and SH8 are machined as turned bar stock units. In Uno 6 to Uno 8, the material that has been held and machined by the first spindle is then held again by the second spindle and machined from the back side.

[0053] The first and second spindles are both turning spindles, one referred to as the main spindle and the other as the sub-spindle. The first and second spindles are positioned opposite each other. In the case of a machine tool 60 without a second spindle, after machining the front side, the workpiece is removed from the first spindle, its orientation is reversed, and then it is gripped again by the first spindle for machining the back side.

[0054] A turning drill unit is a processing unit that uses a turning drill to create a hole in the center of the material. A turning end face unit is a processing unit that removes protruding parts from the front or back end face of the material. A turning bar unit is a processing unit that uses a turning tool to turn the outer circumference, inner circumference, front, or back of a round bar material.

[0055] Figure 10 is a block diagram showing the configuration of the remaining material machining program generation unit according to Embodiment 1. The remaining material machining program generation unit 17 includes a turning program acquisition unit 21, a tool data acquisition unit 22, a machining shape acquisition unit 23, an actual machining shape generation unit 24, a remaining material shape extraction unit 25, a remaining material shape correction unit 26, a process assignment unit 27, and a machining program generation unit 28.

[0056] The turning program acquisition unit 21 receives the turning program 2a generated by the turning program generation unit 16.

[0057] The tool data acquisition unit 22 acquires tool data for the tools specified for each machining unit from the acquired turning program 2a, from the tool data storage unit 14.

[0058] The machining shape acquisition unit 23 acquires the machining shape specified for each machining unit from the acquired turning program 2a.

[0059] The turning program acquisition unit 21, the tool data acquisition unit 22, and the machining shape acquisition unit 23 are responsible for acquiring tool data, which includes information on the tool used for turning on the workpiece and turning conditions; machining information, which indicates the turning method that defines the operation of the tool; material shape data, which indicates the shape of the workpiece; and product shape data, which indicates the shape of the product.

[0060] The actual machining shape generation unit 24 generates the actual machining shape from the tool data acquired by the tool data acquisition unit 22 and the machining shape acquired by the machining shape acquisition unit 23.

[0061] The remaining material shape extraction unit 25 extracts the remaining material shape from the machining shape acquired by the machining shape acquisition unit 23 and the actual machining shape generated by the actual machining shape generation unit 24.

[0062] The remaining material shape extraction unit 25 plays the role of an extraction unit that extracts first shape data indicating the remaining material shape, which is the shape left unmachined during turning, based on tool data, processing information, material shape data, and product shape data.

[0063] The remaining material shape correction unit 26 corrects the first shape data extracted by the remaining material shape extraction unit 25 based on the tool data acquisition unit 22 so as to include the remaining material caused by the cutting edge angle of the tool, and generates second shape data.

[0064] The process assignment unit 27 manages the machining processes to be assigned to the remaining shape, and assigns machining processes to turn the remaining shape based on the remaining shape correction data.

[0065] The machining program generation unit 28 generates a machining program 2b for removing remaining material based on the remaining material shape corrected by the remaining material shape correction unit 26, the turning groove machining shape extracted by the process assignment unit 27, and the tool selected by the tool selection unit 15. The machining program generation unit 28 plays the role of a generation unit that generates a machining program for performing turning, which includes a machining process for turning the remaining material shape based on the second shape data.

[0066] Figure 11 is a flowchart showing the detailed procedure for generating a remaining material machining program performed by the remaining material machining program generation unit of the machining program generation apparatus according to Embodiment 1. The process in Figure 11 corresponds to the process in step S6 of Figure 3.

[0067] In step S11, the remaining material machining program generation unit 17 generates the remaining material shape from the turning program 2a generated by the turning program generation unit 16. Specifically, the remaining material machining program generation unit 17 performs the following processes: extracting first shape data indicating the remaining material shape, which is the shape left unmachined during turning, based on tool data, machining information, material shape data, and product shape data; and correcting the first shape data based on tool data so as to include the remaining material caused by the cutting edge angle of the tool, thereby generating second shape data. Details of this process will be described later.

[0068] In step S12, the remaining material machining program generation unit 17 generates turning machine unit information for the generated remaining material shape and generates the remaining material machining program 2b. That is, the remaining material machining program generation unit 17 performs machining program processing to execute turning, which includes a machining step for turning the remaining material shape. Details of this processing will be described later.

[0069] Based on the above, the machining program generation device 10 completes the process of generating a machining program for remaining material according to the procedure shown in Figure 11.

[0070] Figure 12 is a flowchart showing the detailed procedure for generating the remaining material shape performed by the remaining material machining program generation unit of the machining program generation apparatus according to Embodiment 1. The process in Figure 12 corresponds to the process in step S11 of Figure 11.

[0071] In step S21, the tool data acquisition unit 22 acquires tool data to identify the tool specified in the turning unit. The tool data acquired by the tool data acquisition unit 22 in step S21 includes, for example, the tool number, tool type, and tool magazine number.

[0072] In step S22, the tool data acquisition unit 22 acquires detailed tool data from the tool data storage unit 14 based on the acquired tool data. The detailed tool data acquired in step S22 includes, for example, the cutting edge angle, the secondary cutting edge angle, and the cutting edge radius (R).

[0073] In step S23, the machining shape acquisition unit 23 acquires the machining shape specified by the turning unit.

[0074] In step S24, the actual machining shape generation unit 24 generates an actual machining shape based on the cutting edge angle, using the machining shape and cutting edge angle specified by the turning unit. First, the actual machining shape generation unit 24 extracts edges that are tangent to the product shape from the machining shape. Next, the actual machining shape generation unit 24 obtains the first vertex at the outermost end on the cutting edge angle side. Starting from the first vertex, along the edge tangent to the product shape, the actual machining shape generation unit 24 generates an edge of the cutting edge angle + margin if the tangent vector of the edge is steeper than the cutting edge angle + margin, and trims it. For example, the margin is 3 degrees, but the margin may be set to any angle by the user. By performing this trimming up to the second vertex at the outermost end on the secondary cutting edge angle side of the edge tangent to the product shape, the actual machining shape generation unit 24 generates an actual machining shape based on the cutting edge angle.

[0075] In step S25, the actual machining shape generation unit 24 generates the actual machining shape based on the machining shape and the secondary cutting edge angle specified by the turning unit. First, the actual machining shape generation unit 24 extracts the edges that are tangent to the product shape from the machining shape. Next, the actual machining shape generation unit 24 obtains the second vertex at the outermost end on the secondary cutting edge angle side. Starting from the second vertex, along the edge tangent to the product shape, if the tangent vector of the edge is steeper than the secondary cutting edge angle + margin, the actual machining shape generation unit 24 generates an edge equal to the secondary cutting edge angle + margin and trims it. By performing this trimming up to the first vertex at the outermost end on the cutting edge angle side of the edge tangent to the product shape, the actual machining shape generation unit 24 generates the actual machining shape based on the secondary cutting edge angle.

[0076] In step S26, the actual machining shape generation unit 24 generates the actual machining shape. The actual machining shape generation unit 24 can generate the actual machining shape by integrating the actual machining shape based on the cutting edge angle and the actual machining shape based on the secondary cutting edge angle.

[0077] In step S27, the remaining material shape extraction unit 25 extracts first shape data indicating the remaining material shape, which is the shape left unmachined during turning, based on tool data, machining information, material shape data, and product shape data. By subtracting the actual machining shape from the machining shape of the turning unit, the remaining material shape extraction unit 25 can extract the remaining material shape.

[0078] Based on the above, the machining program generation device 10 completes the process of generating the remaining material shape according to the procedure shown in Figure 12.

[0079] Figures 13, 14, 15, 16, and 17 show an example of the process of generating a remaining material shape from a machined shape in the remaining material machining program generation unit of the machining program generation device according to Embodiment 1. The machined shape SH11 shown in Figure 13 is an example of a machined shape specified in the turning machined unit. The machined shape of the turning machined unit is processed using the cross-sectional shape of the XZ plane, and is therefore a sheet shape that spreads within the XZ plane.

[0080] The machining shape SH12 shown in Figure 14 is an example of the actual machining shape based on the cutting edge angle when the cutting edge angle is 45 degrees. The machining shape SH13 shown in Figure 15 is an example of the actual machining shape based on the secondary cutting edge angle when the secondary cutting edge angle is 45 degrees. The machining shape SH14 shown in Figure 16 is an example of the actual machining shape obtained by integrating the actual machining shape based on the cutting edge angle and the actual machining shape based on the secondary cutting edge angle. The remaining material shapes SH15 and SH16 shown in Figure 17 are examples of remaining material shapes obtained by subtracting the actual machining shape from the machining shape of the turning unit. The remaining material shape SH15 is the remaining material shape on the secondary cutting edge angle side, and the remaining material shape SH16 is the remaining material shape on the cutting edge angle side.

[0081] Figure 18 is a flowchart showing the detailed procedure for generating a machining program for a remaining material shape, performed by the remaining material machining program generation unit of the machining program generation apparatus according to Embodiment 1. The process in Figure 18 corresponds to the process in step S12 of Figure 11.

[0082] In step S31, the remaining material shape correction unit 26 corrects the remaining material shape according to the size of the cutting edge radius R. For example, if the cutting edge radius R is 1 mm, the remaining material shape correction unit 26 moves the bottom edge of the remaining material shape tangentially by 1 mm of the cutting edge radius plus a margin. The margin is, for example, 0.3 mm, but the margin may be set to any length by the user. In the case of the remaining material shape on the cutting edge side, the remaining material shape correction unit 26 moves the bottom edge of the remaining material shape in the -Z direction, and in the case of the remaining material shape on the secondary cutting edge corner side, the remaining material shape correction unit 26 moves the bottom edge of the remaining material shape in the +Z direction. After moving the bottom edges of the remaining material shape on the cutting edge corner side and the remaining material shape on the secondary cutting edge corner side, the remaining material shape correction unit 26 moves the edge of the remaining material shape in the +X direction to the end of the remaining material shape in the +X axis direction in the +X direction. In this way, the remaining material shape correction unit 26 corrects the first shape data based on the tool data to include the remaining material caused by the cutting edge angle of the tool, and generates the second shape data.

[0083] In step S32, the process assignment unit 27 extracts the turning groove machining shape from the remaining material shape. The turning groove machining shape is the shape obtained by extracting the portion to be assigned to the turning groove machining shape from the remaining material shape, based on the groove width, groove depth, and whether or not there is a chamfer.

[0084] In step S33, the process assignment unit 27 generates the shape obtained by subtracting the turning groove machining shape from the remaining material shape as the bar stock machining shape.

[0085] In step S34, the process assignment unit 27 assigns at least one of the following to the remaining material shape: a turning and grooving unit, which is a turning process that turns in the opposite direction to the turning process; and a turning and grooving unit, which is a turning and grooving unit that turns in the opposite direction to the bar stock shape. Here, the process assignment unit 27 assigns the turning and grooving unit to the turning and grooving shape, and assigns the turning and grooving unit that turns in the opposite direction to the bar stock shape generated in step S33.

[0086] In step S35, the machining program generation unit 28 selects a tool using the tool selection unit 15, taking as input the unit type assigned in step S34 and the turning and grooving machining shape extracted in step S32 or the bar stock machining shape generated in step S33.

[0087] In step S36, the machining program generation unit 28 generates a remaining material machining program 2b for turning the remaining material based on the assigned machining unit, the machining shape, and the selected tool. As a result, the machining program generation unit 28 generates a machining program for performing turning, which includes a machining step of turning the remaining material based on the second shape data.

[0088] In this case, since the remaining shape is smaller than the original machined shape, it may be possible to reduce the effort of tool changes and shorten the machining time by machining the remaining shape with a single reverse-turning bar stock machining unit rather than machining the remaining shape with a combination of a turning grooving machine unit and a turning bar stock machining unit that turns in the opposite direction. In such cases, the machining program generation unit 28 generates a remaining shape machining program 2b using only a reverse-turning bar stock machining unit, without generating a turning grooving machine unit. The machining time can be calculated by performing a machining simulation.

[0089] Based on the above, the machining program generation device 10 completes the process of generating a machining program for the remaining material shape according to the procedure shown in Figure 18.

[0090] Figure 19 shows an example of the remaining material shape corrected by the remaining material shape correction unit of the machining program generation device according to Embodiment 1, in accordance with the radius value of the cutting edge R. In the example shown in Figure 19, the product shape is concave. In turning, it is necessary to perform machining while moving the turning tool, the cutting tool 151, along the rotating workpiece. In the example shown in Figure 19, it is necessary to perform machining while continuously moving the cutting tool 151 in the Z direction. For this reason, when cutting into the workpiece with the cutting tool 151, instead of cutting perpendicular to the workpiece, the tool is moved in the Z direction to cut diagonally, and then the turning is performed while maintaining a constant cutting depth. As the cutting tool 151 moves along a path that maintains a constant cutting depth after cutting diagonally, a remaining material shape SH15 is generated on the sub-cutting edge side in areas machined on the cutting edge side, and a remaining material shape SH16 is generated on the cutting edge side in areas machined on the sub-cutting edge side. Thus, in cutting processes, uncut shapes are generated in both the cutting direction and the direction opposite to the cutting direction, depending on the cutting edge angle and the secondary cutting edge angle. Furthermore, because the cutting tool 151 has a cutting edge radius, when cutting with the cutting edge side, an uncut shape SH17 is generated at the bottom of the concave shape, and when cutting with the secondary cutting edge side, an uncut shape SH18 is generated at the bottom of the concave shape.

[0091] The remaining material shape SH21 is an example of a corrected shape that includes the remaining material shape SH17 by moving the bottom edge of the remaining material shape SH15 on the secondary cutting edge corner side by a length equal to (radius value + adjustment amount) of the cutting edge radius in the tangential direction. If the amount of movement of the bottom edge of the remaining material shape SH15 on the secondary cutting edge corner side is equal to the radius value of the cutting edge radius, depending on the machining accuracy, a portion of the remaining material shape SH17 may not be included in the corrected remaining material shape 21. However, by setting the amount of movement of the bottom edge of the remaining material shape SH15 on the secondary cutting edge corner side to (radius value + adjustment amount) of the cutting edge radius, it is possible to suppress the exclusion of a portion of the remaining material shape SH17 from being included in the corrected remaining material shape 21. The remaining material shape SH23 is an example of a further corrected shape by extending the edge of the remaining material shape SH21 in the +X direction in the +X axis direction.

[0092] The remaining material shape SH22 is an example of a corrected shape that includes the remaining material shape SH18 by moving the bottom edge of the remaining material shape SH16 on the cutting edge angle side tangentially by a length equal to (radius value + adjustment amount) of the cutting edge R. If the amount of movement of the bottom edge of the remaining material shape SH16 on the cutting edge angle side is equal to the radius value of the cutting edge R, depending on the machining accuracy, a part of the remaining material shape SH18 may not be included in the corrected remaining material shape 22. However, by making the amount of movement of the bottom edge of the remaining material shape SH16 on the secondary cutting edge angle side equal to (radius value + adjustment amount) of the cutting edge R, it is possible to suppress the exclusion of a part of the remaining material shape SH18 from being included in the corrected remaining material shape 22. The remaining material shape SH24 is an example of a further corrected shape by extending the edge of the remaining material shape SH22 in the +X direction in the +X axis direction.

[0093] Figure 20 is a flowchart showing the detailed procedure for tool selection performed by the tool selection unit of the machining program generation device according to Embodiment 1. The process in Figure 20 is performed when selecting the tools to be used in the turning program 2a and the remaining material machining program 2b, as shown in steps S5 and S6 of Figure 3 and step S35 of Figure 18.

[0094] In step S41, the tool selection unit 15 obtains the maximum cutting edge angle from the turning shape. The maximum cutting edge angle obtained in step S41 is the angle at which the turning shape has the largest angle relative to the turning direction among the edges that make up the product shape.

[0095] In step S42, the tool selection unit 15 obtains the maximum secondary cutting edge angle from the turning shape. The maximum secondary cutting edge angle obtained in step S42 is the angle at which the turning shape has the largest angle relative to the opposite direction of the turning process among the edges that make up the product shape.

[0096] In step S43, the tool selection unit 15 selects from the tool data storage unit 14 a tool that results in zero uncut material, the minimum uncut material, or the uncut material on either the cutting edge side or the sub-cutting edge side, based on the maximum cutting edge angle and the maximum sub-cutting edge angle. For example, if the maximum cutting edge angle is 90 degrees, the maximum sub-cutting edge angle is 0 degrees, and the adjustment angle is 3 degrees, a tool in the range of a cutting edge angle of 87 degrees and a sub-cutting edge angle of 3 degrees is selected. For example, if the maximum cutting edge angle is 45 degrees, the maximum sub-cutting edge angle is 45 degrees, and the adjustment angle is 3 degrees, a tool in the range of a cutting edge angle of 48 degrees and a sub-cutting edge angle of 48 degrees is selected. For example, if the maximum cutting edge angle is 90 degrees, the maximum sub-cutting edge angle is 90 degrees, and the margin angle is 3 degrees, there is no tool in the range of a cutting edge angle of 87 degrees and a sub-cutting edge angle of 93 degrees, so the cutting edge angle is prioritized and a tool in the range of a cutting edge angle of 87 degrees and a sub-cutting edge angle of 3 degrees is selected. This prevents any uncut material from being left on the cutting edge side, leaving only uncut material on the secondary cutting edge side. Note that the operator may choose the tool at their discretion.

[0097] In step S44, if multiple tools are selected, the tool selection unit 15 extracts the tool with the largest cutting edge angle. A tool with a larger cutting edge angle can make a larger cut.

[0098] In step S45, if multiple tools have been selected, the tool selection unit 15 extracts the tool with the largest cutting edge radius. A tool with a larger cutting edge radius can make a larger cut.

[0099] Figures 21, 22, 23, and 24 show an example of the maximum cutting edge angle obtained from a turning shape by the machining program generation device according to Embodiment 1. The machining shape SH31 is a machining shape with a maximum cutting edge angle of 90 degrees and a maximum secondary cutting edge angle of 0 degrees. That is, the tool selection unit 15 obtains a maximum cutting edge angle of 90 degrees and a maximum secondary cutting edge angle of 0 degrees from the machining shape SH31. The machining shape SH32 is a machining shape with a maximum cutting edge angle of 45 degrees and a maximum secondary cutting edge angle of 45 degrees. That is, the tool selection unit 15 obtains a maximum cutting edge angle of 45 degrees and a maximum secondary cutting edge angle of 45 degrees from the machining shape SH32. The machining shape SH33 is a machining shape with a maximum cutting edge angle of 90 degrees and a maximum secondary cutting edge angle of 90 degrees. That is, the tool selection unit 15 obtains a maximum cutting edge angle of 90 degrees and a maximum secondary cutting edge angle of 90 degrees from the machining shape SH33. The machining shape SH34 is a combination of a machining shape with a maximum cutting edge angle of 45 degrees and a maximum secondary cutting edge angle of 45 degrees, and a machining shape with a maximum cutting edge angle of 90 degrees and a maximum secondary cutting edge angle of 90 degrees. The tool selection unit 15 obtains the maximum cutting edge angle of 90 degrees and the maximum secondary cutting edge angle of 90 degrees from the machining shape SH34.

[0100] Based on the above, the machining program generation device 10 completes the tool selection process according to the procedure shown in Figure 20.

[0101] Although this description has focused on a machining system 200 in which a numerical control device 100 is connected to a machine tool 60, the numerical control device 100 may also be mounted on the machine tool 60.

[0102] As described above, the machining program generation device 10 of Embodiment 1 extracts data on the remaining material shape and assigns machining processes based on that data, thereby efficiently creating a machining program 2 that accurately prevents the occurrence of remaining material, and reducing the burden on the program creator. Furthermore, the machining program generation device 10 of Embodiment 1 can reduce material waste while simultaneously improving production efficiency and quality.

[0103] Furthermore, the machining program generation device 10 of Embodiment 1 can minimize or eliminate unmachined material by selecting a turning tool with a limited cutting edge angle. This further improves machining accuracy and reduces material waste. In addition, selecting an appropriate turning tool extends tool life, contributing to cost reduction in the long term.

[0104] Furthermore, the machining program generation device 10 of Embodiment 1 can prevent the generation of unmachined material due to the cutting edge radius by considering the cutting edge radius, overlapping the shape of the remaining material with the original turning shape, and correcting it in the tangential direction according to the shape. This improves machining quality, reduces the need for rework, contributes to shortening machining time, and improves production efficiency.

[0105] Furthermore, the machining program generation device 10 of Embodiment 1 improves machining flexibility by assigning at least one of a turning process that turns in the opposite direction to the remaining material shape and a turning grooving process, thereby shortening machining time while maintaining machining accuracy and improving production efficiency. In addition, appropriate assignment of processes can extend tool life, leading to cost reductions in the long term.

[0106] Next, the hardware configuration of the machining program generation device 10 will be described. Figure 25 is a block diagram showing the hardware configuration of the machining program generation device according to Embodiment 1. Each functional unit shown in Figure 25 comprises a processor 81, a memory 82 used by the processor 81 for the work area, a storage device 83 that stores computer programs describing the functions of the numerical control device 100, an input device 84 which is an input interface with the operator, a display device 85 which is an output device that displays information to the operator, and a communication device 86 which has a communication function with controlled equipment or other numerical control devices. The processor 81, memory 82, storage device 83, input device 84, display device 85, and communication device 86 are connected to each other by a data bus 87.

[0107] The processor 81 is a processing unit, arithmetic unit, microprocessor, microcomputer, CPU (Central Processing Unit), or DSP (Digital Signal Processor), etc. The memory 82 is a non-volatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable ROM), or EEPROM (Registered Trademark) (Electrically EPROM), a magnetic disk, a flexible disk, an optical disk, a compact disk, a minidisc, or a DVD (Digital Versatile Disc).

[0108] The shape input unit 11, shape placement unit 13, tool selection unit 15, turning program generation unit 16, and remaining material processing program generation unit 17 of the numerical control device 100 can be realized by the processor 81 reading and executing a computer program stored in the memory 82.

[0109] Furthermore, multiple processors 81 and multiple memories 82 may work together to realize each function of the numerical control device 100. Alternatively, some of the functions of the shape input unit 11, shape placement unit 13, tool selection unit 15, turning program generation unit 16, and remaining material processing program generation unit 17 may be implemented as electronic circuits, while the other parts are realized using the processors 81 and memories 82.

[0110] The configurations shown in the above embodiments are merely examples of the content, and can be combined with other known technologies. It is also possible to omit or modify parts of the configuration without departing from the gist of the invention.

[0111] 1 CAD data, 2 Machining program, 2a Turning program, 2b Remaining material machining program, 10 Machining program generation device, 11 Shape input unit, 12 Shape data storage unit, 13 Shape placement unit, 14 Tool data storage unit, 15 Tool selection unit, 16 Turning program generation unit, 17 Remaining material machining program generation unit, 20 Dialogue operation processing unit, 21 Turning program acquisition unit, 22 Tool data acquisition unit, 23 Machining shape acquisition unit, 24 Actual machining shape generation unit, 25 Remaining material shape extraction unit, 26 Remaining material shape correction unit, 27 Process assignment unit, 28 Machining program generation unit, 30 Instruction input unit, 40 Display unit, 50 Control unit, 60 Machine tool, 81 Processor, 82 Memory, 83 Storage device, 84 Input device, 85 Display device, 86 Communication device, 87 Data bus, 100 Numerical control device, 151 bytes, 200 machining systems.

Claims

1. A machining program generation device comprising: an acquisition unit that acquires tool data including information on the tool and turning conditions used for turning a workpiece; machining information indicating a machining method for turning that defines the operation of the tool; material shape data indicating the shape of the workpiece; and product shape data indicating the shape of the product; an extraction unit that extracts first shape data indicating the unmachined shape, which is the shape left unmachined in the turning process, based on the tool data, the machining information, the material shape data, and the product shape data; an unmachined shape correction unit that corrects the first shape data extracted by the extraction unit based on the tool data so as to include the unmachined shape caused by the curvature of the cutting edge of the tool, and generates second shape data; and a generation unit that generates a machining program for performing the turning process, including a machining step of turning the unmachined shape, based on the second shape data.

2. The machining program generation apparatus according to claim 1, further comprising a tool selection unit that selects the tool by limiting the cutting edge angle in a machining process for turning the remaining shape, thereby minimizing the amount of material left to be removed.

3. The machining program generating device according to claim 1 or 2, characterized in that the generating unit generates a machining program for performing the turning process by assigning at least one of a turning process and a turning grooving process to the remaining shape, which is turned in the opposite direction to the turning process.

4. A numerical control device comprising a machining program generation device according to any one of claims 1 to 3, and a control unit that executes the machining program and controls a machine tool.

5. A machining system comprising a numerical control device according to claim 4 and a machine tool controlled by the numerical control device.

6. A method for generating a machining program, comprising the steps of: acquiring tool data including information on the tool used for turning on a workpiece and turning conditions; machining information indicating a machining method for turning that defines the operation of the tool; material shape data indicating the shape of the workpiece; and product shape data indicating the shape of the product; extracting first shape data indicating a remaining shape, which is a shape left unmachined in the turning process, based on the tool data, the machining information, the material shape data, and the product shape data; correcting the extracted first shape data based on the tool data so as to include the remaining shape caused by the cutting edge angle of the tool, and generating second shape data; and generating a machining program for performing the turning process, including a machining step of turning the remaining shape, based on the second shape data.

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