Numerical control device and method for controlling movement of a processing tool for processing inner surface of a recessed portion preformed in a workpiece

Abstract

The numerical control device (100) comprises a main control unit (110), a processing program reading unit (120), and a tool movement path setting unit (130) for setting a movement path of a processing tool (14) between a plurality of recesses, wherein the tool movement path setting unit (130) comprises: a tool retraction position setting unit (132) for setting a retraction position (P2) of the processing tool (14) after the inner surface processing is completed; a tool tip stop angle setting unit (134) for setting a stop angle of the tool tip based on the movement direction to the next recess; and a tool retraction path setting unit (136) for setting a retraction path (ER) of the processing tool (14), wherein the stop angle is set so that the direction toward which the tool tip is directed does not have a movement vector component in the same direction as the movement direction.

Description

Technical Field

[0001] The present invention relates to a numerical control device and a numerical control method for controlling the movement of a processing tool for processing the inner surface of a recessed portion preformed on a workpiece. Background Art

[0002] In the machining of a workpiece, sometimes inner surface machining is performed to machine the inner surface of a recessed portion (e.g., a lower hole for hole machining or groove machining) pre-formed in the workpiece into a predetermined shape. As such inner surface machining, methods such as boring machining (boring machining) are known.

[0003] When the tool that has finished such inner surface processing on the concave portion is controlled to move to the next command point, the control device of the processing device controls the relative movement of the processing tool and the workpiece along the path toward the command point after temporarily withdrawing the processing tool from the concave portion where the inner surface processing has been completed. As such processing, the case where the relative movement of the processing tool and the workpiece is controlled along a continuous processing path connecting concave portions formed at multiple locations of the workpiece can be exemplified, but in this case, the command point on the processing program from the concave portion after processing to the concave portion to be processed next is generally constituted as a straight line connecting the centers or centroids of two concave portions.

[0004] As an example of such inner surface processing, the following constant depth processing device and processing method are disclosed in Patent Document 1, the constant depth processing device comprising: a tool head, which holds a rotating tool for cutting a workpiece; a worktable, which supports the workpiece; a feed unit, which feeds the tool head in a cutting direction; a unit for setting a target cutting amount from a reference surface of the workpiece; a unit for setting a temporary cutting position for feeding the tool head to a position close to the target cutting amount; a measuring unit, which has a pair of sensors, respectively connected to the reference surface of the workpiece and the reference surface of the workpiece. The present invention provides a method for detecting the positions of the cutting surfaces of the temporary cutting by detecting the positions of the cutting surfaces of the temporary cutting, and measuring the cutting amount from the reference surface of the workpiece by the difference between the two positions; a calculation unit that calculates the remaining cutting amount by subtracting the cutting amount based on the temporary cutting measured by the measurement unit from the target cutting amount; and a control unit that controls the feeding unit so as to perform temporary cutting by feeding the tool head to the temporary cutting position, and then perform final cutting by feeding the tool head to the final cutting position obtained by adding the calculated remaining cutting amount to the position of the cutting surface cut by the temporary cutting. Thus, the workpiece can be cut with high precision without almost generating an error in the cutting amount from the reference surface.

[0005] In addition, patent document 2 discloses a workpiece processing method and a processing device for performing the processing. The workpiece processing method is a workpiece processing method for boring a hole formed in a workpiece, and is characterized in that it comprises: a first step of rough-processing the inner circumference of the hole using a polishing tool; a second step of cutting the inner circumference of the rough-processed hole using a tool; and a third step of fine-processing the inner circumference of the cut hole using a polishing tool.

[0006] Thus, when the inner peripheral surface of the hole of the workpiece is polished in the third step after the cutting in the second step, deformation of the hole due to cutting resistance is suppressed and a flat surface can be formed by performing the polishing.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application Laid-Open No. 8-174320

[0010] Patent Document 2: Japanese Patent Application Publication No. 2018-51738 Summary of the invention

[0011] Problems to be solved by the invention

[0012] However, in the inner surface machining of the concave portion formed in the workpiece using a common numerical control device, the machining origin and reference axis (e.g., three axes of XYZ) for holding the workpiece and moving the machining tool are set for the machining device performing the inner surface machining, and the relative movement of the workpiece and the machining tool is performed based on these machining origins and reference axes. At this time, in the machining program for the inner surface machining, in order to simplify the description of the machining instructions, the stop position or stop direction of the machining tool at the end of the inner surface machining of one concave portion (lower hole) is sometimes always set to the same direction (e.g., always toward the X direction or always toward the direction of the program origin of the machining tool, etc.).

[0013] However, when the processing tool is retreated from the concave portion and moved in a predetermined moving direction after the inner surface processing is completed, if the stop position or stop direction of the processing tool is always set to the same direction, the processing tool must be moved in a direction that does not include the same vector component as the moving path of the next indicated point in the "avoidance action" of the processing tool retreating from the processed concave portion. Therefore, when the inner surface processing of the concave portion is controlled, the moving path of the processing tool after processing increases, resulting in a problem of increasing the moving path of the processing tool in the entire processing program.

[0014] Under such circumstances, there is a demand for a numerical control device and a numerical control method that can avoid an increase in the moving path of a machining tool after the inner surface machining is completed when performing inner surface machining of a recessed portion formed in advance in a workpiece.

[0015] Means for solving problems

[0016] A numerical control device for controlling the movement of a machining tool for performing inner surface machining on a recessed portion preformed on a workpiece according to one embodiment of the present invention comprises: a main control unit that issues a machining command to a machining device based on a machining program; a machining program reading unit that pre-reads the machining program; a tool movement path setting unit that sets a movement path of the machining tool after the inner surface machining is completed, the tool movement path setting unit including: a tool retraction position setting unit that sets a retraction position of the machining tool relative to the recessed portion after the inner surface machining is completed based on the pre-read machining program; a tool tip stop angle setting unit that sets a stop angle of a tool tip attached to the machining tool when the inner surface machining is completed based on a moving direction of the machining tool from the retraction position; and a tool retraction path setting unit that sets a retraction path from a stop position of the machining tool when the inner surface machining is completed to the retraction position, the stop angle being set so as to be within a stop range defined as a direction in which the front end of the tool tip faces and does not have a moving vector component in the same direction as the moving direction of the machining tool.

[0017] In addition, one embodiment of the present invention involves a numerical control method for controlling the movement of a processing tool for performing inner surface processing on a recess pre-formed on a workpiece, including: pre-reading a processing program, and setting a tool movement path setting action for setting the movement path of the processing tool after the inner surface processing is completed, and the tool movement path setting action also includes: a step of setting a retreat position of the processing tool relative to the recess after the inner surface processing is completed based on the pre-read processing program; a step of setting a stop angle of the tool tip mounted on the processing tool when the inner surface processing is completed based on the movement direction of the processing tool from the above-mentioned retreat position; and a step of setting a retreat path from the stop position of the processing tool when the inner surface processing is completed to the retreat position, and setting the above-mentioned stop angle to be within a stop range defined as a direction toward which the front end of the tool tip is directed and does not have a movement vector component in the same direction as the movement direction of the processing tool.

[0018] Effects of the Invention

[0019] According to one embodiment of the present invention described above, an action is performed to set a retreat position of a machining tool relative to a recess after inner surface machining is completed based on a pre-read machining program, an action to set a stop angle of a tool tip mounted on the machining tool when inner surface machining is completed based on a moving direction of the machining tool from the above-mentioned retreat position, and an action to set a retreat path from the stop position of the machining tool when inner surface machining is completed to the retreat position. The stop angle at this time is set to be within a stop range defined as a direction in which the front end of the tool tip faces a direction that does not have a moving vector component in the same direction as the moving direction of the machining tool. Thus, when performing inner surface machining of a recess pre-formed in a workpiece, an increase in the moving path of the machining tool after the inner surface machining is completed can be avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a block diagram showing the relationship between a numerical controller and its peripheral devices for controlling the movement of a machining tool for machining the inner surface of a recessed portion formed in advance on a workpiece according to the first embodiment of the present invention.

[0021] Figure 2 This is a diagram showing an overview of relative movement between a workpiece and a processing tool in a numerical control method for controlling movement of a processing tool for processing the inner surface of a recessed portion formed in advance in the workpiece according to the first embodiment.

[0022] Figure 3A yes Figure 2 A partial cross-sectional view of section A1-A1.

[0023] Figure 3B yes Figure 2 A partial cross-sectional view of section A1-A1.

[0024] Figure 4 This is a flowchart showing an example of a process of determining a tool stop angle and a tool retraction path in a retraction operation from a recessed portion of a machining tool, which is executed by the numerical controller according to the first embodiment.

[0025] Figure 5A This is a diagram showing an overview of relative movement between a workpiece and a processing tool in a numerical control method for controlling movement of a processing tool for performing inner surface processing on a recessed portion formed in advance on a workpiece according to a second embodiment.

[0026] Figure 5B This is a diagram showing an overview of relative movement between a workpiece and a processing tool in a numerical control method for controlling movement of a processing tool for performing inner surface processing on a recessed portion formed in advance on a workpiece according to a second embodiment.

[0027] Fig. 6AThis is a diagram showing an overview of relative movement between a workpiece and a processing tool in a numerical control method for controlling movement of a processing tool for performing inner surface processing on a recessed portion formed in advance on a workpiece according to a third embodiment.

[0028] Figure 6B This is a diagram showing an overview of relative movement between a workpiece and a processing tool in a numerical control method for controlling movement of a processing tool for performing inner surface processing on a recessed portion formed in advance on a workpiece according to a third embodiment. DETAILED DESCRIPTION

[0029] Hereinafter, an embodiment of a numerical control device and a numerical control method for controlling the movement of a machining tool for machining the inner surfaces of a plurality of recessed portions, which is a representative example of the present invention, will be described with reference to the drawings.

[0030] <First embodiment>

[0031] Figure 1 This is a block diagram showing the relationship between a numerical control device and its peripheral devices for controlling the movement of a machining tool for machining the inner surface of a recessed portion pre-formed on a workpiece in a first embodiment as a representative example of the present invention. Figure 2 This is a diagram showing an overview of the relative movement between a workpiece and a processing tool in a numerical control method for controlling the movement of a processing tool for performing inner surface processing on a recessed portion preformed in a workpiece according to a first embodiment. Figure 3A and Figure 3B yes Figure 2 A partial cross-sectional view of section A1-A1.

[0032] Here, the "inner surface processing" in the present application specification includes a technology for further cutting or finishing the inner surface of a hole or groove (hereinafter referred to as "lower hole") pre-processed on the workpiece W, and can be exemplified by a processing technology such as boring processing in which a tool tip protruding in the circumferential direction from a processing tool rotating in a top view contacts the inner surface of a recessed portion and the center of the rotating spindle does not move. In addition, in the present application specification, in a processing program for processing the inner surface of a recessed portion, it includes a processing tool being located (returned) at the processing origin or a predetermined designated point (for example, before and after a series of processing) of the processing device 10. Figure 2 The action of the starting point SP1 and the ending point SP2 shown.

[0033] like Figure 1As shown in FIG. 1 , as an example, the numerical control device 100 includes: a main control unit 110 that issues a processing instruction to a processing device (control object) 10 based on a processing program stored in an external storage device 20; a processing program reading unit 120 that pre-reads the processing program from the external storage device 20; and a tool movement path setting unit 130 that sets the movement path of the processing tool 14 before and after the processing of the recessed portion H1 formed on the workpiece W. The numerical control device 100 is configured to be communicably connected to the processing device 10 or the external storage device 20 via a wired or communication line, etc., and can issue various control instructions to the processing device 10 and receive detection signals from various sensors (not shown) installed in the processing device 10. In addition, the numerical control device 100 can also be configured to be connected to various input devices, display devices, and other auxiliary devices not shown, or include them.

[0034] Here, the structure of the processing device 10 is not limited as long as it can perform the above-mentioned "inner surface processing", but as an example, a structure including a processing table holding the workpiece W and a rotating mechanism such as a spindle holding and rotating the rotating member 12 can be applied. In addition, the processing device 10 numerically controls the position of the processing table or the rotating mechanism based on the control command signal from the numerical control device 100, thereby executing the processing operation including the inner surface processing and the tool movement operation including the retraction operation of the processing tool.

[0035] In addition, if Figure 2 As shown, the processing tool 14 is mounted on the lower end of a substantially cylindrical or substantially cylindrical rotating member 12 in a manner that the tool tip 14a protrudes radially, and revolves on the outer circumference of the rotating member 12 as the rotating member 12 rotates. In addition, the rotating member 12 is mounted on a rotating mechanism (not shown) such as a spindle of the processing device 10, and is configured to be able to perform three-dimensional relative movement relative to the workpiece W. As a result, the tool tip 14a of the rotating processing tool 14 contacts the inner surface Ha of the recess H formed in the workpiece W to perform inner surface processing.

[0036] The main control unit 110 is a unit that issues an action command signal to the control object 10, and as an example, includes: a function of combining a program block of a machining program read by a machining program reading unit 120 described later with a movement command of a machining tool 14 generated by a tool movement path setting unit 130 to generate a control command signal to be sent to the machining device 10, and a function of receiving detection signals from various sensors (not shown) provided in the machining device 10 and correcting the control command signal according to the detection values ​​thereof, etc. In addition, the main control unit 110 may also include a function of adding or correcting a control program stored in the external storage device 20 as needed.

[0037] As an example, the processing program reading unit 120 includes: a function of pre-reading the processing program blocks from the external storage device 20 one by one and analyzing them to determine what control instructions are included in the pre-read processing program blocks; and a function of temporarily storing and saving the pre-read processing program blocks. Then, if the pre-read processing program blocks do not include a processing end instruction, the processing program reading unit 120 sends the program blocks to the main control unit 110, and if the processing end instruction is included, the processing program reading unit 120 sends the program blocks read thereafter to the main control unit 110, and sends them to the tool movement path setting unit 130 described later in parallel.

[0038] The tool movement path setting unit 130 includes a tool retreat position setting unit 132 which sets a retreat position P2 (see FIG. 1 ) of the machining tool 14 relative to the recess H after the inner surface machining is completed based on the program block of the machining program received from the machining program reading unit 120. Figure 3B ); a tool tip stop angle setting unit 134, which sets the stop angle of the tool tip 14a mounted on the processing tool 14 when the inner surface processing is completed based on the moving direction MD2 that the processing tool 14 will move from the above-mentioned retreat position P2; a tool retreat path setting unit 136, which sets the retreat path ER from the stop position P1 of the processing tool 14 when the inner surface processing is completed to the retreat position P2. In addition, the tool movement path setting unit 130 has the following functions: when it is determined that the program block of the processing program pre-read by the processing program reading unit 120 is a processing end instruction, the program block group after the processing end instruction is received and the program block group is temporarily accumulated. Here, as Figure 2 As shown, as an example, the moving direction MD2 refers to the program origin or predetermined designated point (refer to FIG. 1 ) at which the processing tool 14 is located (returned) in the processing device 10 before and after processing, which is included in the processing program as described above. Figure 2 The direction of movement of the processing tool 14 caused by the action of symbol SP2).

[0039] The tool retreat position setting unit 132 analyzes the control instructions included in the program block group of the processing program temporarily accumulated as described above, determines the movement start position (retreat position P2) when the processing tool 14 moves from the currently processed recessed portion H to the specified point SP2 after processing, and sets its representative point. Figure 2 As shown, as a representative point indicating the retreat position P2, for example, a retreat point EP where the rotation center CP of the lower end portion of the rotating member 12 to which the processing tool 14 is attached is located can be used.

[0040] The tool tip stop angle setting unit 134 has the following function: when, in accordance with the machining end instruction included in the machining program, for example, the rotation of the rotating member 12 is stopped at the recessed portion H1 being machined to execute the "avoidance action" of the machining tool 14, the tool tip 14a attached to the front end of the machining tool 14 is set to the angle (stop angle) at which the tool tip 14a is directed when it stops. Here, as an example, the "stop angle" of the tool tip 14a can be set to the angle with respect to the rotation axis ( Figure 2 In a plane orthogonal to the axis passing through the rotation center CP, a predetermined axial direction (such as the X direction of the worktable holding the workpiece W, etc.) is used as a reference axis, and an absolute angle between 0° and 360° is defined relative to the reference axis.

[0041] In the present invention, the stopping angle of the blade edge 14a defined as above is, for example, Figure 2 The stop range SR is defined as a stop range SR in which the direction TD in which the front end of the blade tip 14a is directed does not have a moving vector component from the recess H in the same direction as the moving direction MD2 described above. Figure 2 In the specific example shown, the stop range SR is set to a range of 180° orthogonal to the circumferential direction of the rotating member 12 relative to the moving direction MD. Figure 3B As shown, when the tool tip 14a of the processing tool 14 mounted on the rotating part 12 leaves the inner surface Ha of the recess H after the inner surface processing is completed, it always performs a retreat action in the direction having the same vector component as the moving direction MD2 (i.e., a direction not reverse to the moving direction MD2), so the moving path of the processing tool 14 will not increase.

[0042] In addition, if Figure 2 As shown, the above-mentioned stop angle is preferably set to the angle at which the direction TD that the front end of the blade tip 14a is facing and the moving direction MD2 are on the same straight line and become the opposite direction. Thus, the stop angle of the blade tip 14a can be easily set based on the moving direction MD2, so additional calculations are not required, and the burden of the program maker can also be reduced.

[0043] like Figure 3B As shown, the tool retreat path setting unit 136 has the function of generating and setting a retreat path ER for retreating the rotating member 12 and the processing tool 14 from, for example, the stop position P1 of the processing tool 14 when processing the inner surface of the recess H is completed to the retreat position P2 set by the tool retreat position setting unit 132. Figure 3B In the specific example shown, the retraction path ER is set as a line that linearly connects the rotation center CP at the stop position P1 and the retraction point EP at the retraction position P2.

[0044] After these processes, the tool movement path setting unit 130 determines the movement path from the recessed portion H to the designated point (end point) SP2 including the evacuation action based on the evacuation path ER set by the tool evacuation path setting unit 136 as the tool movement path setting action, and sends the action information to the main control unit 110. Then, the main control unit 110 that has received the action information generates a movement command of the processing tool 14 corresponding to the movement path, and sends it to the processing device 10, thereby executing control of the processing device 10.

[0045] Figure 4 This is a flowchart showing an example of a process for determining a tool stop angle and a tool retraction path in a retraction operation from a concave portion of a machining tool executed by a numerical control device according to the first embodiment. Figure 4 The flowchart shown can be implemented in parallel with the processing instruction action in the main control unit 110. As an example, when the processing program reading unit 120 identifies a program block of the processing end instruction in the processing control instruction executed by the main control unit 110 for the processing device 10, it can also be executed in parallel with the processing instruction for the inner surface of the recess.

[0046] like Figure 4 As shown, in the operation of determining the tool retracting path of the machining tool 14 in the first embodiment, the tool moving path setting unit 130 receives the program blocks of the machining program pre-read by the machining program reading unit 120 (step S1) and temporarily accumulates them (step S2).

[0047] Next, the tool retreat position setting unit 132 determines the moving direction MD2 from the recessed portion currently being processed to the designated point SP2 to which the processing tool 14 is to move next, based on the program block group of the processing program currently stored (step S3).

[0048] Here, in the tool retraction position setting unit 132, it is determined whether the moving direction MD2 can be determined (step S4). Then, if it is determined in step S4 that the moving direction MD2 can be determined, the tool retraction position P2 (or the retraction point EP) for the recessed portion currently being processed is determined based on the determined moving direction MD2 (step S5).

[0049] At this time, as an example, on the same straight line corresponding to the moving direction to the designated point, the retreat point EP is selected from the position where the rotation center CP coincides when the shape of the machining tool 14 is projected onto the recessed portion currently being machined (for example, the recessed portion H). On the other hand, if it is determined in step S4 that the moving direction MD2 can be determined, the process returns to step S1, and the program blocks of the machining program are read ahead and accumulated again.

[0050] Next, the tool tip stop angle setting unit 134 sets the tool tip stop angle of the tool tip 14a of the processing tool 14 at the end time of processing the concave portion currently being processed on the inner surface (step S6). At this time, the tool tip stop angle can be pre-defined by the processing program as in the past, or can be calculated using a calculation formula using various processing conditions.

[0051] Next, the blade stop angle setting unit 134 determines whether the blade stop angle set in step S6 is within the above-mentioned predetermined stop range ( Figure 2 symbol SR) (step S7).

[0052] When it is determined in step S7 that the set tool nose stop angle is within the stop range SR, it is considered that the tool nose stop angle is appropriate, and the process proceeds to the subsequent steps.

[0053] On the other hand, if it is determined in step S7 that the set tool nose stop angle is outside the stop range SR, it is considered that the tool nose stop angle is inappropriate, and the process returns to step S6 to reset the tool nose stop angle. Through this series of actions, the tool nose stop angle at the end of the inner surface machining, which is one of the features of the present invention, can be set within a predetermined stop range.

[0054] Next, the tool retreat path setting unit 136 determines Figure 3B The tool movement path setting unit 130 determines the escape path ER from the stop position P1 to the escape position P2 of the processing tool 14 (step S8), and the tool movement path setting unit 130 sends the action information of the tool movement path setting action including the escape action based on the escape path ER determined in step S8 to the main control unit 110 (step S9), and the program ends. Then, the main control unit 110 executes the tool movement action based on the action information of the tool movement path setting action.

[0055] Through the above-mentioned structure and action, the numerical control device and the numerical control method of the first embodiment of the present application execute: based on the pre-read processing program, the action of setting the retreat position of the processing tool relative to the recess after the inner surface processing is completed, the action of setting the stop angle of the tool tip installed on the processing tool when the inner surface processing is completed based on the moving direction of the processing tool from the above-mentioned retreat position, and the action of setting the retreat path from the stop position of the processing tool when the inner surface processing is completed to the retreat position, and the stop angle at this time is set to be within the stop range defined as the direction in which the front end of the tool tip faces does not have a moving vector component in the same direction as the moving direction of the processing tool, thereby, when performing the inner surface processing of the recess pre-formed in the workpiece, the moving path of the processing tool after the inner surface processing is completed can be avoided from increasing.

[0056] <Second embodiment>

[0057] Figure 5A as well as Figure 5B FIG. 1 is a diagram showing an overview of the relative movement of a workpiece and a processing tool in a numerical control method for controlling the movement of a processing tool for performing inner surface processing on a recessed portion preformed on a workpiece in a second embodiment as another example of the present invention. Figure 1 The block diagram shown, Figure 4 In the flowcharts and the like shown in the drawings, components that can adopt the same or common configurations as those of the first embodiment are denoted by the same reference numerals, and duplicate descriptions are omitted.

[0058] In the second embodiment, the following case is illustrated: for a plurality of recesses pre-formed on a workpiece, the movement of a processing tool is controlled when the inner surface of the plurality of recesses is continuously processed. In addition, the “plural recesses” may include a case where a plurality of lower holes are formed in one workpiece W, or a case where a plurality of workpieces W having recesses H1 are arranged in a processing device.

[0059] In a second embodiment, if Figure 5B As shown in the partial cross-sectional view of the A2-A2 section of FIG. 1 , the tool movement path setting unit 130 sets the movement path from the stop position P1 of the processing tool 14 at which the inner surface processing of one recess H1 is completed to the processing start position P3 of the recess H2 to be processed next. At this time, the "movement direction in which the processing tool is to move next" shown in the first embodiment is, for example, the direction of the line connecting the retreat point in the recess at which the inner surface processing is completed and the processing start point of the recess to be processed next ( Figure 5A as well as Figure 5B It is given the figure mark MD).

[0060] The tool retreat position setting unit 132 analyzes the control instructions included in the program block group of the processing program temporarily accumulated as described above, determines the movement start position (retreat position P2) when the processing tool 14 moves from the currently processed recessed portion H1 to the next recessed portion H2 to be processed, and sets its representative point. Figure 5B As shown, as a representative point indicating the retreat position P2, a retreat point EP where the rotation center CP of the lower end portion of the rotating member 12 to which the processing tool 14 is attached is located is used as an example.

[0061] The tool tip stop angle setting unit 134 sets the angle (stop angle) of the tool tip 14a attached to the front end of the processing tool 14 when it stops, in accordance with the processing end command included in the processing program, in the same manner as in the first embodiment. Here, in the second embodiment, the stop angle of the tool tip 14a is set to be within a stop range SR defined as a direction TD toward which the front end of the tool tip 14a is directed without a moving vector component in a direction coaxial with the moving direction MD from the recessed portion H1 toward the recessed portion H2 to be processed next.

[0062] Therefore, if Figure 5B As shown, when the tool tip 14a of the processing tool 14 mounted on the rotating member 12 leaves the inner surface H1a of the recess H1 after the inner surface processing is completed, the tool tip 14a always performs a retreat action in a direction having the same vector component as the moving direction MD (i.e., a direction not counter to the moving direction MD), so the moving path of the processing tool 14 does not increase. In addition, as in the case of the first embodiment, the above-mentioned stop angle is preferably set to an angle at which the direction TD toward which the front end of the tool tip 14a is directed is opposite to the moving direction MD on the same straight line.

[0063] like Figure 5B As shown, the tool retreat path setting unit 136 has the function of creating and setting a retreat path ER for retreating the rotating member 12 and the processing tool 14 from the stop position P1 of the processing tool 14 when processing the inner surface of the recess H1 is completed, for example, toward the retreat position P2 set by the tool retreat position setting unit 132. Figure 5B In the specific example shown, the retraction path ER is set as a line that linearly connects the rotation center CP at the stop position P1 and the retraction point EP at the retraction position P2.

[0064] After these processes, the tool movement path setting unit 130 determines the movement path from the recess H1 to the recess H2 including the evacuation action based on the evacuation path ER set by the tool evacuation path setting unit 136 as the tool movement path setting action between the recesses, and sends the action information to the main control unit 110. Then, the main control unit 110 that has received the action information generates a movement command of the processing tool 14 corresponding to the tool movement path setting action, and sends it to the processing device 10, thereby controlling the processing device 10.

[0065] By performing such an action, in the second embodiment, in addition to the effects obtained by the numerical control device and the numerical control method of the first embodiment, a series of movement actions of the processing tool such as continuous inner surface processing between a plurality of recesses can be controlled. In addition, the movement direction MD of the processing tool after the inner surface processing of one recess (e.g., recess H1) is defined each time as the direction toward the recess (e.g., H2) to be processed next, so the movement control of the processing tool can be performed without stopping the processing control of a series of processing programs and without increasing the burden on the program creator.

[0066] <Third embodiment>

[0067] Fig. 6A as well as Figure 6B FIG. 1 is a diagram showing an overview of the relative movement of a workpiece and a processing tool in a numerical control method for controlling the movement of a processing tool for performing inner surface processing on a recessed portion preformed in a workpiece, according to a third embodiment of the present invention as another example. Figure 1 The block diagram shown, Figure 4 In the flowcharts and the like shown in the drawings, components that can adopt the same or common configurations as those of the first embodiment are denoted by the same reference numerals, and duplicate descriptions are omitted.

[0068] In the third embodiment, the retraction path ER set by the tool retraction path setting unit 136 is composed of the following paths: a first retraction path ER1 from the stop position P1a at the end of the inner surface machining to the separation position P1b where the rotation axis of the rotating member 12 on which the machining tool 14 is mounted is parallelly moved by a predetermined distance D; and a second retraction path ER2 from the separation position P1b to the retraction position P2. At this time, for the predetermined distance D, it is considered that the current machining program or the independent variable of the past machining program is used, the case where it is determined according to the rotation radius of the machining tool 14, or the case where it is determined as a predetermined value set for each control device, etc. In addition, the parallel movement of the machining tool 14 is performed in the direction of the tool tip 14a toward the rotation center CP.

[0069] By performing such an action, in the third embodiment, in addition to the effects obtained by the numerical control device and the numerical control method of the first embodiment, after the inner surface machining is completed, the machining tool 14 can first be made to evade from the inner surface Ha of the recessed portion H along the first evacuation path ER1, thereby reliably avoiding damage to the inner surface Ha of the recessed portion H after the machining during the evacuation action. Figure 6B As shown, the parallel movement of the first escape path ER1 is performed in a direction including the same vector component as the moving direction MD2 in which the machining tool will move next, so that the increase in the moving path of the machining tool can be avoided.

[0070] In addition, Fig. 6A In the specific example shown, as the amount of movement D of parallel movement based on the first escape path ER1, the distance from the rotation center CP at the stop position P1a to the position directly below the escape point EP of the escape position P2 is exemplified, but as a modified example of the third embodiment, it is also possible to configure such that the amount of movement D can be arbitrarily selected. Thus, for example, in the inner surface machining of the recessed portion H, the amount of cut-in varies in the depth direction, and when there are irregularities on the inner surface Ha, the amount of parallel movement D is set to be larger than the amount of protrusion of the irregularities, and contact between the inner surface Ha of the recessed portion H and the machining tool 14 can be avoided during the escape operation.

[0071] The present invention is not limited to the above-described embodiment, and can be appropriately modified without departing from the gist of the invention. The present invention can modify any structural element of the embodiment or omit any structural element of the embodiment within the scope of the invention.

[0072] Description of Reference Numerals

[0073] 10 Processing equipment,

[0074] 20 external storage device,

[0075] 100 numerical control devices,

[0076] 110 Main control unit,

[0077] 120 Processing program reading unit,

[0078] 130 tool movement path setting unit,

[0079] 132 tool retreat position setting unit,

[0080] 134 blade stop angle setting unit,

[0081] 136 Tool retreat path setting unit.

Claims

1. A numerical control device for controlling the movement of a machining tool for machining the inner surface of a recessed portion preformed on a workpiece, characterized in that: The numerical control device comprises: A main control unit that issues processing instructions to the processing device based on the processing program; a processing program reading unit that pre-reads the processing program; and a tool movement path setting unit, which sets the movement path of the processing tool after the inner surface processing is completed, The tool movement path setting unit includes: a tool retreat position setting unit that sets a retreat position of the machining tool relative to the recessed portion after the inner surface machining is completed based on the pre-read machining program; a tool tip stop angle setting unit that sets a stop angle of a tool tip attached to the processing tool when the inner surface processing is completed based on a moving direction of the processing tool from the retreat position; and a tool retreat path setting unit for setting a retreat path from a stop position of the machining tool when the inner surface machining is completed to the retreat position, The stop angle is set to be within a stop range defined as a direction in which the tip of the blade edge faces does not have a movement vector component in the same direction as the movement direction.

2. The numerical control device according to claim 1, characterized in that: The stop angle is set to an angle such that the direction in which the tip of the blade edge is directed is in the opposite direction to the moving direction and is on the same straight line.

3. The numerical control device according to claim 1 or 2, characterized in that: The retreat path further includes a first retreat path from the stop position toward a direction in which the rotation axis of the processing tool is parallelly moved, and a second retreat path toward the retreat position.

4. The numerical control device according to claim 3, characterized in that: The amount of the parallel movement is determined in accordance with the shape of the recessed portion after processing.

5. The numerical control device according to claim 1 or 2, characterized in that: A plurality of recessed portions are formed in advance on the workpiece, and the moving direction is set to a direction connecting a retreat point in a recessed portion where inner surface processing has been completed and a processing start point of a recessed portion to be processed next.

6. The numerical control device according to claim 1 or 2, characterized in that: The recessed portions are formed in advance on a plurality of workpieces, and the moving direction is set to a direction connecting a retreat point in a recessed portion for which inner surface processing has been completed and a processing start point of a recessed portion to be processed next.

7. A numerical control method for controlling the movement of a machining tool for machining the inner surface of a recessed portion preformed on a workpiece, characterized in that: The numerical control method comprises: pre-reading a machining program, setting a tool movement path setting action of setting a movement path of the machining tool after the inner surface machining is completed, The tool movement path setting action also includes: A step of setting a retracted position of the processing tool relative to the recessed portion after the inner surface processing is completed based on the pre-read processing program; The step of setting a stop angle of a tool tip attached to the processing tool when the inner surface processing is completed based on a moving direction of the processing tool from the retreat position; and a step of setting a retreat path from a stop position of the machining tool at the end of the inner surface machining to the retreat position, The stop angle is set to be within a stop range defined as a direction in which the tip of the blade edge faces does not have a movement vector component in the same direction as the movement direction.

8. The numerical control method according to claim 7, characterized in that: The stop angle is set to an angle such that the direction in which the tip of the blade edge is directed is in the opposite direction to the moving direction and is on the same straight line.

9. The numerical control method according to claim 7 or 8, characterized in that: The retreat path further includes a first retreat path from the stop position toward a direction in which the rotation axis of the processing tool is parallelly moved, and a second retreat path toward the retreat position.

10. The numerical control method according to claim 9, characterized in that: The amount of the parallel movement is determined in accordance with the shape of the recessed portion after processing.

11. The numerical control method according to claim 7 or 8, characterized in that: A plurality of recessed portions are formed in advance on the workpiece, and the moving direction is set to a direction connecting a retreat point in a recessed portion where inner surface processing has been completed and a processing start point of a recessed portion to be processed next.

12. The numerical control method according to claim 7 or 8, characterized in that: The recessed portions are formed in advance on a plurality of workpieces, and the moving direction is set to a direction connecting a retreat point in a recessed portion for which inner surface processing has been completed and a processing start point of a recessed portion to be processed next.

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