KR950008029B1 - Nc machine tool with automatic tool exchange device - Google Patents

Abstract

No content.

Description

Numerically controlled machine tool for automatic tool change

1 is a block diagram illustrating the configuration of the invention described in claims 1 and 2;

2 is a perspective view of a compact integral machining center as an embodiment;

Figure 3 (a) is a front view of the tool magazine employed in the embodiment.

Figure 3 (b) is an X-X longitudinal cross-sectional view thereof.

3 (c) is a rear view of the tool magazine.

4 is a front view including a partially broken surface inside the machining center showing the drive mechanism of the tool change arm.

5 is a bottom view of the tool changer arm.

6 is a front view of a workpiece fixed to an index table.

7 is a block diagram showing a connection relationship between a control device of the embodiment and respective motors;

8A is an explanatory diagram showing a method of setting an interference area for each of the workpiece surfaces of a workpiece.

FIG. 8B is an explanatory diagram of a method of setting the interference region in the case where rotation is accompanied by B in the same manner.

9 is a flowchart of a closest retraction height calculation process.

10 is a flowchart of tool change processing.

* Explanation of symbols for main parts of the drawings

M1: Current Process Tool M2: Spindle

M3: Spindle Head M4: Next Process Tool

M5: Tool magazine M6: Means for preparing the next process tool

M7: Tool change arm M8: Spacer change means

M9: Means for calculating non-interfering closest approach position M10: Means for approaching closest

M11: Tool change operation inhibiting means M12: Work surface changing means

M13: Interference zone indicating means when changing the workpiece surface

M14: Prohibition means for changing the surface to be processed

P1: Tool index switch P2: Space out position

T: Tool W: Workpiece

WT: Workpiece Peripheral Device 1: Machining Center

3,3next: Tool 5: Spindle Head

7: Tool magazine 9: Tool change arm

11: colum 13: worktable

13a: X axis motor 13b: Y axis motor

15: Index table 15: B axis motor

19: vertical motion motor 21: spindle

23: spindle motor 29a ~ 29h, 29 next: tool port

31: magazine motor 41: swinging motor

49a, 49b: finger 51: camshaft

53: tool change motor 70: electronic control device

83: keyboard 85: vertical position sensor

C: Tool drawing shaft M: Magazine shaft

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a numerically controlled machine tool which automatically performs tool change while continuously machining a workpiece while exchanging a tool stored in a tool magazine according to a machining program.

Background Art In a conventional machine tool such as a machining center, it is known to continuously process a workpiece while exchanging a tool stored in a tool magazine in accordance with a machining program. As such a machine tool, there exist some which were described, for example in Unexamined-Japanese-Patent No. 63 (1988) -123646. The machine tool integrally assembles the tool magazine and the spindle head. When the tool is changed, the spindle head is moved up and down along the column to change the separation distance between the workpiece and the tool tip. The tool magazine houses various tools such as taps, drills, or reamers of different sizes and shapes.When the tool change timing is performed, the tool magazine is rotated to index the tool, and the swing mechanism is moved to swing the tool port. After changing the tool of the next step in the same direction as the tool of the current step, the exchange arm was driven to perform the tool change.

However, in the conventional apparatus, the spindle head is retracted to the origin position of the top of the column so that the respective tools, workpieces and peripherals of the current process and the next process do not interfere during this tool change. Therefore, since it takes time for the transition from the current step to the next step, and it is not the time for directly processing the workpiece, it is not possible to improve the processing efficiency.

In addition, this is integrated with the spindle head and the tool magazine, and even if the machine tool itself is small, the tool change cannot be performed unless a large operation is carried out. There was no. Therefore, there was a problem that the merit of the small integrated type could not be saved enough.

The machine tool of the present invention has an object of enabling a tool change to be performed with a minimum of operations, and in particular, in a compact integrated type device, the merits can be drawn out.

The numerically controlled machine tool which automatically performs tool change according to claim 1 of the present invention, as illustrated in FIG. 1, detachably supports the tools M1 and 3 provided for machining the workpiece in the present process. It has the main shaft (M2, 21) to rotate, the main shaft (M2, 21) by rotating the axis of rotation in the center of rotation to rotate the tools (M1, 3) supported on the main shaft (M2, 21) work W Spindle heads M3 and 5 for processing the tool and a threaded portion 29 for storing the plurality of tools T, and the plurality of tools T stored in the storage portion 29 for processing in the next step. Tool magazines M5 and 7 for moving the provided tools M4 and 3 next to a predetermined exchange position, and tools M1 and 3 and tool magazines of the current process supported by the spindle heads M3 and 5; Supported by the tool change arm 9 and the spindle head M3, 5 for exchanging with the tool M4, 3 next of the next process moved to the predetermined exchange position in M5, 7). Workpiece peripheral devices WT, 13, and 15 that support the workpiece W to be machined by the spheres M1 and 3, spindle heads M3 and 5, and workpiece peripheral devices WT, 13, and 15 In the machine tool provided with the column 11 which supports the axial direction of the spindle head M3, 5 so that it can move relatively, the tool M1,3 of the present process supported by the spindle head M3, 5 is carried out. In accordance with the length in the axial direction and the length in the axial direction of the tool (M4, 3 next) of the next step moved to the predetermined exchange position, and the size of the work piece (W) (M7, 9). ), The tool (M1,3 or M4,3 next) of the longer tool (M1,3 or M4,3 next) in the axial direction among the current tool (M1,3) and the next tool (M4,3 next). Non-interfering approach position calculation means for generating the closest retraction height required between the spindle heads M3 and 5 and the workpiece peripheral devices WT and 13 and 15 so that the tip does not interfere with the workpiece W. ( M9,71, 74,76) After the end of the machining by the tool M1, 3 of the current step supported by the head M3, 5, the spindle heads M3, 5 and the workpiece peripheral devices WT, 13, 15 are subjected to the non-interfering close approach. In order to take the closest retraction height generated by the position calculating means M9, 71, 74, 76, the separation position changing means M8, 19 are driven to drive the spindle heads M3, 5 and the workpiece peripheral device WT, It is characterized in that it is provided with the closest retraction means (M10, 71, 72, 85) for moving 13, 15 in the axial direction of the spindle head (M3, 5) relatively.

In addition, the numerically controlled machine tool for automatically performing tool change of the substrate according to claim 2 of the present invention, in addition to the above-described configuration, as shown by the dashed-dotted line in FIG. Work surface changing means (M12, 17, 72, 15b) for changing the work surface of the work (W) by rotating the work (W) around an axis perpendicular to a plane including an axis extending in the axial direction of the work (W). And the tool change operation by the tool change arms M7 and 9 and the surface change means (M12, 71, 72, 15b) when the tool change and the work surface change are designated in the next step. Means for calculating the non-interfering approach position of the interference area between the tool (M1,3 or M4,3 next) and the workpiece (W) determined in accordance with the overlap of the work surface change operation of the workpiece (W) by And interference area indicating means (M13, 71, 74, 76) for changing the surface to be applied to M9, 71, 74, 76; The nearest approach position calculating means (M9, 71, 74, 76) is the tool change arm (M7, 9) in accordance with the data of the intermediate interference area from the surface changer interference area indicating means (M13, 71, 74, 76). The tool M1 in the current process is performed even when the workpiece W is changed by rotating the workpiece W by the workpiece changing means M12, 71, 72, and 15b. (3) and the head of the main shaft so that the tip of the tool (M1,3 or M4,3 next) having a longer length in the axial direction among the tools (M4,3 next) in the next step does not interfere with the workpiece (W). Generates the closest retraction height required between M3,5 and the workpiece peripheral devices WT, 13,15, and the closest retraction means M10,71,72,85 are the spindle heads M3,5. After the end of the machining by the tool M1, 3 of the current step supported by (), the spindle heads M3, 5 and the workpiece peripheral devices WT, 13, 15 are subjected to the non-interfering closest position calculating means M9. To take the closest retraction height generated by (71,74,76) , By driving the separation position changing means (M8, 19) to move the spindle head (M3, 5) and the workpiece peripheral device (WT, 13, 15) in the axial direction of the spindle head (M3, 5) relatively. do.

According to the numerically controlled machine tool which automatically performs tool change according to claim 1 of the present invention, in the case of executing tool change while leaving the workpiece surface of the workpiece W intact, the non-interfering closest position calculating means ( M9) refers to the dimensions and shape of the current process tool M1 and the next process tool M4, so that both the tools M1 and M4 are formed of the workpiece peripheral device WT and the workpiece W such as a work table. With respect to the interference region determined from the shape, no one penetrates through the tool exchange operation and the position at which one approaches most is calculated. At the time of tool change, in accordance with the calculation result of the non-interfering closest position calculating means M9, the closest retracting means M10 drives the spacing position changing means M8, and the spindle head M3 and the tool magazine M5. ) And the tool change box (M7) are relatively evacuated to a position that is the non-interfering closest approach to the workpiece peripheral (WT) and the workpiece (W). In the meantime, the tool change operation prohibiting means M11 prohibits the operation of the next process tool preparation means M6 and the tool change arm M7 until the operation of the closest retraction means M10 is completed. Accordingly, only the minimum evacuation operation is performed on the spindle head M3, the tool magazine M5, and the tool change box M7, and the current process tool M1 and the next process tool M4 are operated through the tool change operation. There is no interference with the workpiece W and its peripheral device WT. As a result, the tool change is performed at a position close to the length avoiding the interference.

Further, according to the numerically controlled machine tool which automatically performs tool change according to claim 2 of the present invention, the workpiece surface changing means for changing the workpiece surface of the workpiece W in accordance with a machining process, for example, as an index table. (M12), when the tool change and the workpiece surface change are designated in the next step, the interference area indicating means M13 at the time of the workpiece surface change The interference region determined according to the overlap is given to the non-interfering optimum near-position calculating means M9. Therefore, the non-interfering closest approach position calculating means M9 calculates the non-interfering closest approach position in consideration of this machining surface change operation. As a result, the closest retraction means M10 retracts the spindle head M3, the tool magazine M5, and the tool change arm M7 to the non-interfering closest approach position at the time of the work surface change. In the meantime, not only the tool changing operation inhibiting means M11 prohibits the operation of the next process tool preparation means M6 and the tool changing arm M7, but also the workpiece surface changing operation inhibiting means M14 is the closest evacuation means ( The operation of the workpiece surface changing means M12 is prohibited until the operation of M10 is completed. As a result, in the case where a process for executing tool change and work surface change is instructed, tool change and work surface diameter are executed with minimal operation.

The work surface changing operation includes not only the rotational operation by the index table but also the case where the work between the work surfaces having different heights is executed by the X-Y table.

EMBODIMENT OF THE INVENTION Next, the Example which actualized this invention is described in detail according to drawing.

2 shows a machining center 1 with an index table of the embodiment.

The machining center 1 comprises a spindle head 5 detachably supporting a tool 3 used for machining, a tool magazine 7 integrally assembled to the side of the spindle head 5, and a spindle head ( 5), a tool change arm 9 integrally assembled with them in the middle of the tool magazine 7, a colum 11 for supporting the spindle head 5 from the back, and a lower part of the colum 11; It is provided with a work table 13 attached to the movable table XY itself, and an index table 15 mounted on the upper right side of the work table 13 to rotate the work W around the B axis.

The spindle head 5 is slidably mounted to the column 11 through a set of rails 17 and 17 extending up and down the front of the column 11, and is supported by the rail motor 17 by the vertical motor 19. And (17) slide up and down. The separation position changing means M8 slides the main shaft head 5 up and down on a set of rails 17 and 17 extending up and down the entire surface of the column 11 by the rotation of the vertical motion motor 19. As such, the operation is executed in accordance with the instruction from the closest evacuation means M10. Thereby, the spindle head 5 and the work peripheral device WT are moved relatively in the axial direction of the spindle head 5, and the tool change arm 9 is used to change the current step (3) and the next step. Since the tip of the longer tool 3 or 3next in the axial direction of the tool 3 next does not interfere with the work W, there is an effect of positioning the spindle head 5. Moreover, the tool 3 is supported by the main shaft 21 which has a clamp mechanism inside. The spindle 21 is driven by the spindle motor 23 to process the work W by the tool 3 supported at its tip.

The tool magazine 7 is rotatably mounted integrally with the magazine shaft M orthogonal to the Z axis of the spindle 21 on the side of the spindle head 5. The tool magazine 7 includes eight port arms 27a to 27h radially mounted on the rear side of the magazine body 25, as shown in Figs. Tool arms 29a to 29h pivotably supported on arms 27a to 27h are provided. Each tool port 29a-29h accommodates one tool each, such as a drill, a tap, or a reamer. In the center of the rear surface of the tool magazine 7, a high reduction ratio hypoid gear 37 composed of a pinion 33 which is rotationally driven by the magazine motor 31 and a waiting gear 35 engaged with the staggered shaft is mounted. . The tool magazine 7 rotates the magazine shaft M around the magazine shaft 31 via the hypoid gear 37 to hold the tool ports 29a to 29h in which the desired tools are stored. Move to the lower tool index switch (P1).

The tool port 29e moved to the tool index switch P1 is rocked about 90 degrees by the swinging motor 41 through the gripping rod 39e disposed on the back thereof, and moves downward. The aspect is shown by a dashed-dotted line in FIG. 3 (b). As shown in the figure, in the tool index switch P1, the holding rod 39e is inserted between the holding clicks 45 and 45 of the rocking arm 43. As shown in FIG. This rocking arm 43 is driven by the rocking motor 41 provided in the upper part of the spindle head 5 in parallel with the magazine motor 31. When driving the swinging motor 41 to pull the swinging arm 43 upward, the tool port 29e faces downward and is set at the tool take-off position P2.

The tool change arm 9 is mounted on the lower end of the change arm axis 47 installed in the spindle head 5, as shown in FIG. 4, and has a pair of fingers 49a and 49b at both ends. . The tool change arm shaft 47 performs a series of operations of raising, lowering, turning and finger opening and closing by the rotation of the cam shaft 51 disposed side by side. The camshaft 51 is rotationally driven by a tool change motor 53 provided on the right side of the spindle head 5.

5, the reference state in which the tool change arm 9 spreads the fingers 49a and 49b is shown. In this reference state, the length L9 of the tool change arm 9 is such that one finger 49a touches the tool 3 supported by the main shaft 21, while the other finger 49b is in the tool withdrawal position ( The length reaches the next process tool (3 next) brought on the tool take-off shaft C of P2). In addition, the exchange arm shaft 47 is an intermediate position between the tool pull-out shaft C and the main shaft 21 passing through the tool pull-out position P2. Therefore, when the tool correction arm 9 is rotated 180 degrees, the fingers 49a and 49h at both ends are replaced so that the tool can be gripped at the positions of the tool take-out shaft C and the main shaft 21.

The operation of the switch arm 9 will be briefly described with reference to FIGS. 4 and 5. In the above-mentioned reference state, when the camshaft 51 is rotated by the tool change motor 53, first, the cam flaw 55a on the upper surface of the first cam member 55 is operated to oscillate gear 57a on the left side of the figure. Swings a predetermined angle. A rotating gear 57a is engaged with the swinging gear 57a. When the rotary gear 57b is rotated by a predetermined amount, the opening and closing rod 59 for inserting the inside of the exchange arm shaft 47 is rotated so that both fingers 49a are rotated. And 49b are closed at the same time. Thus, both tools 3 and 3 next are gripped by the tool change arm 9 in the illustration.

Subsequently, the cam groove 61a of the outer circumference of the second cam member 61 is operated to push the collet chuck 63 provided in the main shaft 21 into an open state, and the tool 3 is unclamped. In addition, the cam flap 65a of the outer circumference of the third cam member 65 is operated to push down the exchange arm shaft 47 to move the two tools 3 and 3 next to the spindle 21 and the tool port 29 next. Simultaneously pull out from At this time, the exchange arm shaft 47 is engaged with the sleeve 67 by a spline provided on the outer circumferential surface. When the cam plate 69a of the fourth cam member 69 of the cam shaft 51 is operated, the sleeve 67 is operated. Each turn is 180 degrees.

Thereafter, the third cam member 65 is again operated to raise the tool change arm 9, and both tools 3 and 3 next are replaced to be stored in the tool port 29 next and the main shaft 21. do. Subsequently, further, the second cam member 61 is operated, the collet chuck 63 of the main shaft 21 is closed, and the first cam member 55 is operated again before the end of one rotation of the cam shaft 51, This time, the swinging gear 57a swings in the reverse direction as described above, and the fingers 49a and 49b are opened.

Tool change is thus carried out very quickly and accurately. In addition, the action of the cam in a series of operations performed while the camshaft 51 is rotated in one rotation is described in detail in Japanese Patent Application Laid-Open No. 63 (1988) -123646 filed by the present applicant. Please refer to it.

An index table 15 for rotatably processing the work W is shown in FIG. This index table 15 clamps the workpiece | work W from up, down, left, and right, and processes this workpiece | work W to the workpiece mounting surface 15a. The workpiece W is rotated around the B axis by the B axis motor 15b to change the surface to be processed.

FIG. 7 shows the relationship between the electronic control device 70 that controls drive control and the like in this embodiment, each motor, and the like.

The electronic control device 70 controls the entire control and the three of the master CPU 71, the slave CPU 72 which manages the workpiece hole, and the automatic tool change CPU (ATC unit CPU) 73 which controls the tool change. It consists of two CPUs.

The master CPU 71 includes a master RAM 74 that stores programs, constants, and the like for operating the control device itself, a first master RAM 75 that temporarily stores variables, flags, and the like during control execution, and tool exchange. The second master unit RAM 76, which stores a machining program for instructing timing, a tool used for work processing, and the like, is connected. The second master RAM 76 is backed up even when the power is turned off.

The slave CPU 72 is connected to a slave unit ROM 77 for storing motor drive programs, constants, and the like for workpiece machining, and a slave unit RAM 78 for temporarily storing variables, flags, and the like during workpiece machining control. have.

The ATC unit CPU 73 includes an ATC unit ROM 79 that stores exchange arm drive programs and constants for tool change, and an ATC unit RAM 80 that temporarily stores variables, flags, and the like during tool change control execution. Connected.

Between the master CPU 71 and the slave CPU 72, a common RAM 81 between MSs for storing instructions from the master CPU 71 to the slave CPU 72 or a signal in the reverse direction, other information, and the like is connected. It is. The common RAM 81 between the MSs is connected. In the inter-MS common RAM 81, information is written or referenced from both the master CPU 71 and the slave CPU 72.

In addition, between the master CPU 71 and the ATC unit CPU 73, the common RAM between the MAs in which a command from the master CPU 71 to the ATC unit CPU 73 or a signal in the reverse direction, other information, and the like are stored ( 82 is connected. Similar to the inter-MS common RAM 81 described above, in the inter-MA common RAM 82, information is written or referenced from both the master CPU 71 and the ATC unit CPU 73.

The master CPU 71 is also connected with a keyboard 83 for creating and inputting a machining program and the like, and a CRT 84 for displaying and referring to the machining program and the like. In addition, the master CPU 71 is connected to an up-down position sensor 85 that detects the up-down absolute position of the spindle head 5 that changes in accordance with the rotation of the up-and-down motion motor 19, and receives this detection signal.

The slave CPU 72 includes an X-axis motor 13a for moving the work table 13 in the X-axis direction, a Y-axis motor 13b for moving in the Y-axis direction, and a B-axis motor for rotating the index table 15. And a control signal are sent to each of the motors 13a, 13b, and 15b to change the work surface and the work position of the work W. The slave CPU 72 is also connected to the vertical motion motor 19 and the main shaft motor 23. The slave CPU 72 sends control signals to the slave CPU 72, and a predetermined tool for the workpiece W determined as the work surface and the work position. Execute machining by

On the other hand, the ATC unit CPU 73 is connected to the magazine motor 31 and the swinging motor 41, and sends a control signal to the magazine motor 31 to rotate the tool magazine 7 to perform the next process of the tool (3). next) is moved to the tool index switch P1, the control signal is sent to the swinging motor 41, and the next process tool port 29 next at this index position P1 is rocked on the tool take-out side C. To prepare the next process tool. In addition, the ATC unit CPU 73 is also connected to the tool change motor 53, sends a control signal to this, and drives the cam shaft 51 described above to execute tool change.

The workpiece machining control and the tool change control executed by these slave CPUs 72 and the ACT unit CPU 73 are executed in accordance with an instruction from the master next 71. The master CPU 71 reads and inputs the machining program inputted from the keyboard 83 and stored in the second master RAM 76 one by one operation. The read-in input information relates to the workpiece processing and the common RAM between MSs ( On page 81). The slave CPU 72 reads the written information, determines the rotation speed of the main shaft motor 23, and the like, and executes the above-described work processing control. Similarly, when tool change is instructed in the machining program, information is transmitted and received through the common RAM 82 between the MAs, and tool change control by the ATC unit CPU 73 is executed. In this tool change control, the slave CPU 72 also controls the movement and rotation of the work table 13 and the index table 15 at the same time. As described later, the workpiece W and The master CPU 71 instructs the slave CPU 72 and the ATC unit CPU 73 to control timing in order to prevent the respective tools 3 and 3 next exchanged with the peripheral device 15 from colliding with each other. have.

Next, information about the interference area for avoiding the interference of the work W and the peripheral device with the tools 3 and 3 next during tool change among the machining programs and information input from the keyboard 83 is given. The setting method will be described.

The interference region is input as separate information when there is no B-axis rotation and when there is B-axis rotation with respect to the four workpiece surfaces W1 to W4 of the work W. As shown in FIG.

When there is no B-axis rotation, as shown in FIG. 8A, the workpiece heights ZW1, ZW2, etc. on the base of each to-be-processed surface are input. The predetermined height of force Z0 is applied to the workpiece heights ZW1 and ZW2 as the interference heights Z fix1 and Z fix2 and stored in the predetermined addresses of the second master RAM 76. The same applies to the other two surfaces W3 and W4.

On the other hand, when there is B-axis rotation, as shown in FIG. 8 (b), the trunk height is input for each B-axis rotation direction and the workpiece to be processed after the change.

For example, as shown by the solid line, when the workpiece | work W exists in the position which puts the 1st processing surface W1 up, the 1st processing surface W1 of the 1st processing surface like the dashed-dotted line shown in figure is shown. When the workpiece | work W is rotated counterclockwise as shown to the 2nd to-be-processed surface W2 corresponding to the right side, the upper right angle K1 of the workpiece | work W of the present process passes the highest position. Therefore, the passage height Z1-2 is input from the keyboard 83, and the value which added the safety height X0 to the passage height Z1-2 makes the to-be-processed surface the 2nd from the 1st surface W1. Is stored in a predetermined address of the second master RAM 76 as the interference height Z index1-2 at the time of changing the workpiece surface when changing to the surface W2.

In the case where the machining surface is changed from the first machining surface W1 to the fourth machining surface W4 corresponding to the left side, as shown in the dashed-dotted line, the upper left angle of the workpiece W ( K4) passes through the highest point, and the interference height Z index1-4 is stored in the predetermined address of the second MR unit RAM 76 when the workpiece surface is changed by applying the safety height Z0 to the passage height Z1-4. . The interference height in case of these B-axis rotations is input for each condition according to the to-be-processed surface before and after a change, and B-axis rotation direction. In addition, when these information inputs the shape, the machining position, etc. of the workpiece | work W from a CAD system, the input data of this CDA system is rotated, and the information as the interference height (Z index) at the time of B-axis rotation from the trace | track May be automatically created.

In addition, from the keyboard 83, information of the eight types and dimensions of the eight tools stored in each of the tool ports 29a to 29h of the tool magazine 7 is input, and the information in the second master RAM 76 is entered. It is stored in the tool management map.

The master unit CPU 71 refers to the interference heights Z fix1, Z, index1-2 and the like, and at the same time, depending on the machining conditions (working surface, tool to be used, etc.) of the next process written in the machining program, Calculate the minimum height at which the main axis should be evacuated (hereinafter referred to as the non-interfering close approach height). The processing is shown in FIG.

Before finishing the current machining process, the tool (3 next) and the B-axis rotation of the next process read and input the machining conditions (Step S1: Hereinafter, each step is described as S1, etc.). If the B-axis rotation is specified among the conditions, the interference height (Z index) at which the above-described machining surface change determined from the wave surface and the B-axis rotation direction of the current process and the next process is determined. Set to Z base (S2, S3). On the other hand, when the next step does not involve the B-axis rotation, the interference height Z fix described in FIG. 8A is set to the non-interfering approach height reference value Z base (S4).

Next, the tool length L next of the next process tool (3 nest) and the tool length (L now) of the current process tool (3 now) are read from the tool management map of the second master unit RAM 76, and both Comparing with the length of the evacuation tool length (L avoid) (S5). This evacuation tool length (L avoid) is added to the above-mentioned non-interfering close approach reference height (Z base), and the tool extraction distance (Z dowm) according to the vertical movement of the exchange arm (9) at the time of tool change is added to the closest retraction. The height Z change is obtained (S6).

This closest retreat height X change is calculated until the end of the current process is completed and written in the common RAM 81 between MSs. In addition, a tool (3 next) to be selected as a machining condition for the next step is written into the common RAM 81 between the MSs and the common RAM 82 between the MAs, and the workpiece movement amount and rotation amount are written into the common RAM 81 between the MSs. . The information of the next process tool 3 next written in the common RAM 81 between the MSs is used in the slate CPU 72 to determine the spindle speed, for example, by the pitch of the drill. The information of the next process tool (3 next) written in the common RAM 82 between the MAs is the amount of the magazine motor 31 to be rotated in the ATC unit CPU 73, for example, at tool index. It is used for calculation.

When the current process is completed, the slave CPU 72 and the ATC unit CPU 73 read out the information of each of the common RAMs 81 and 82, respectively, and execute the tool change processing shown in FIG. In addition, in the figure, the control command from the master CPU 71 is described in the center, the control command of the slate CPU 72 is described on the right side, and the control command of the ATC unit CPU 73 is described on the left side.

When the processing of the present process is completed, the master CPU 71 commands the stop of the main shaft motor 23 (S11), and commands the rise of the main shaft head 5 (S12). The slave CPU 72 receives each command, stops the main shaft motor 23 (S13), and starts up / down motion motor 19 (S14).

The master CPU 71 refers to the detected value of the up-down position sensor 85 to determine whether the spindle head 5 has reached the closest retraction height Z change calculated in the processing shown in FIG. 9 ( S15). When the spindle head 5 reaches the closest retraction height Z change, a command is issued to stop the spindle head from the position (S16), and the up-and-down motion motor 19 is stopped on the slave CPU 72 side (S16). S17).

Thus, after the spindle head 5 is positioned at the closest retraction height Z change, the spindle orientation S18 and the next process tool index S19 are commanded. Upon receiving this, the main shaft motor 23 is started / stopped on the slate CPU 72 side, and the main shaft orientation is executed (S20), and the magazine motor 31 is started / stopped on the ACT unit CPU 73 side, and the next process tool is executed. The index of (3 next) is executed (S21).

The master CPU 71 waits for the tool index completion signal from the ATC unit CPU 73 and sends a next process tool preparation instruction (S22). Upon receipt of this next process tool preparation instruction, the swing motor 41 is started / stopped on the ATC unit CPU 73 side, and the next process tool 3 next is prepared downward on the tool take-off shaft C. (S23).

In addition, although description was made so that control of S18, S19, S22 may be performed in order for convenience of description, it does not need to implement in this order in practice. That is, since the control of S20 is executed by the slave CPU 72 and the control of S21 and S23 is executed by the ATC unit CPU 73, it can be executed at all independently. Moreover, even if the tool index is executed, interference does not occur to the work W, so the tool index may be executed until the evacuation operation of the spindle head 5 is completed. Therefore, in the actual control, the timing is set so that the preparation process (S22, S23) of the next process tool is executed immediately after the evacuation operation of the spindle head 5 is completed, thereby shortening the working time.

The master CPU 71 issues a signal from the ATC unit CPU 73 that the preparation of the next process tool 3 next has been completed and sends an exchange arm drive command (S24). In response to this command, the ATC unit CPU 73 starts / stops the tool change coater 53 to rotate the cam shaft 51 as described above, and the current step is performed on the tool change arm 9 as described above. Tool replacement is promptly completed by carrying out the gripping, extracting, turning, inserting and opening operations of the tool 3 and the next process tool (3 next) (S25).

Also, at the same time as the tool change, the B axis is rotated from the master CPU 71 to the slave CPU 72, and a command is issued to index the machining surfaces W1 to W4 instructed in the next step. In response to this command, the B-axis motor 15b is started / stopped, and the machining surfaces W1 to W4 of the next step are indexed (S27). In addition, when a process surface change is not specified in the next process, the process of S26 and S27 is not performed.

Although the description is made here so that the control of S24 and S26 is executed in order, the control of S25 and S27 is executed by the slate RAM 72 and the ATC unit CPU 73 separately, and can be duplicated. Further, the above-described next process tool preparation (S22, S23) and the surface index to be processed (S26, S27) can also be overlapped. Therefore, in practice, the surface indexes S26 and S27 control the timing so as to be executed quickly after the evacuation operations S11 to S17 of the spindle head 5 are completed.

Subsequently, an instruction to return the tool port 29 next set downward on the tool take-out shaft C is sent to the ATC unit CPU 73 (S28), and the swing motor is transmitted by the ATC unit CPU 73. 41 is started / stopped and the tool port 29 next is returned (S29).

When the signal indicating that the return of the tool port 29 next is completed is sent from the ATC unit CPU 73, the lowering of the spindle head 5 is commanded (S30), and the slave CPU 72 side moves the up / down motor 19. The process of starting by reverse rotation is performed with the above-mentioned (S31). Thereafter, when the spindle head 5 is lowered and the tip of the tool (3 next) of the next process reaches a height in contact with the workpiece surfaces W1 to W4 of the workpiece W (S32), it moves up and down according to the machining program. The motor 19 and the main shaft motor 23 are drive controlled to start the work processing of the next step.

As described above, according to this embodiment, the spindle head 5 is quickly retracted after the type of machining to change the tool and change the machining surface. Moreover, this retraction position is controlled by the closest retraction height (Z change) obtained in the closest retraction height calculation processing (S1 to S6), so that the interference between the tools (3), (3 next) and the workpiece (W) is reduced. It does not occur, and the time required for the evacuation of the spindle head 5 is minimized. Therefore, the indirect working time can be greatly reduced in the work of machining the workpiece while minimizing the grain size accompanying the notification exchange, and the efficient workpiece processing can be realized.

In addition, by minimizing the operation during machining of the compact integrated machining center 1, the merit of the small shape can be exhibited to the maximum. As a result, since the space occupied by the machining center 1 can be minimized in the processing plant, it is optimal for use in a narrow plant.

Since only a small device is used and a large evacuation operation is the same as that in which the tool magazine is separately placed at the evacuated position, the merit of the miniaturization as described above has not been achieved. However, according to this embodiment, this problem can be solved.

Moreover, since the spindle head 5, the tool magazine 7, and the tool change arm 9 are integrally formed, these three parties do not interfere with each other. Therefore, the interference of these three parties need not be considered at all, and only the simple approach based on the detected value of the vertical position sensor 85 is calculated by calculating the closest retraction height Z change. As a result, no control miss occurs, and a reliable evacuation operation can always be realized.

In addition, the tool magazine 7 is configured to arrange the tool along the magazine axis M orthogonal to the main shaft 21, and the swinging arm 43 is operated to swing the tool port 29 next downward. The operation S22 of preparing the tool 3 next on the tool take-out shaft C is configured to be executed immediately upon completion of the retraction operation S11 to S17 of the spindle head 5. Therefore, if the tool change is performed with the minimum working time and the tool of the next process is very long compared with the current process, it is brought to the tool take-off position P2 before the evacuation actuator of the spindle head 5 is completed. The state of interference with the work W is prevented from occurring. As a result, in any case, the tool change operation can be performed safely and reliably in the shortest time.

On the other hand, in calculating the non-interfering close approach height Z change, as shown in FIG. 8B, the highest point of the trajectory through which the work W passes is taken into consideration. As a result, when the retraction operation of the spindle head 5 is completed, no interference occurs even if the tool change operation and the workpiece surface change operation are executed. As a result, when the evacuation operation of the spindle head 5 is completed, the work surface change operation can be executed immediately, regardless of the progress of the tool change operation. Therefore, in the case of changing the tool and changing the surface to be processed, even if both operations are performed in duplicate, the interference between the tools 3, 3 next and the workpiece W can be avoided, and further, the shortest working time can be achieved. The preparation for the next process can be completed. In particular, the effect of obtaining the non-interfering approach height (Z change) in consideration of this trajectory does not need to adjust the timing of the control that differs in the types of tool change and workpiece surface change, respectively. Since only the completion of the operation is taken into consideration, the effect of very simple control is obtained. Therefore, no control miss occurs.

Incidentally, in the embodiment, the case where the present invention is applied to the small integrated machining center 1 is described. However, the spindle head, the tool magazine, and the tool change arm may be moved up and down by a separate driving source. In any case, by carrying out the control for evacuating the spindle head, the tool magazine and the tool change to the non-interfering closest approach position before the tool change, the time involved in the tool change can be shortened, so that efficient work can be realized.

Moreover, although the example which calculates from the length of a tool was shown in calculation of a non-interference closest approach position, it is not limited to this, It is good also as a structure which considers the thickness, the tip shape, etc. of a tool. In addition, it is good also as a structure which considers also the track | route which a tool turns.

In addition, as a study to shorten the working time, the tool indexes S19 and S21 may be configured to be completed beforehand during the current process. In addition, the workpiece surface change may be performed at the stage of reaching the pass heights (Z1-2, Z1-4) and the like when the spindle head 5 reaches the non-interfering approach height (Z change). It is good also as a structure to start. In this way, if the various timings are controlled more precisely, time can be shortened.

In addition, the change of the surface to be processed includes not only the rotation around the B axis but also the movement in the X-Y plane. That is, what is necessary is just to set it as the structure which calculates the non-interference closest approach height from the external shape and the to-be-processed position, when the workpiece | work W is a different shape. Also in this case, the tool change operation and the work surface change operation can be executed in duplicate, and further, since the retraction distance of the main shaft head is minimal, the effect of shortening the working time is high.

In the embodiment, the completion of evacuation is determined as an absolute position, but an incremental sensor may be used. In addition, since the embodiment is an absolute system, it is not necessary to determine how much the vertical motor should be driven to evacuate to the non-interfering approach height, and the calculation and control are simple.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above, and various aspects within the scope not departing from the gist, such as a configuration in which the worktable side moves up and down instead of the main shaft head side, may be employed. have.

As described above, according to the claimed invention of Claims 1 and 2, relative evacuation of the spindle head and the workpiece during tool change can be minimized. Therefore, the time required for tool change can be minimized, and the tool change time, which is an indirect work time in the work for machining the work, can be greatly reduced, and efficient work processing can be realized.

In addition, execution of the next process tool is prohibited until this evacuation operation is completed. As a result, even if the tool magazine or the like is integrally mounted on the spindle head, the next process tool is prepared after the evacuation operation is completed, and there is no fear of interference with the workpiece. Therefore, interference can be reliably avoided in performing the work of performing tool change in the closest position.

As a result, the present invention can be applied to, for example, a small integrated machine tool, and the merits thereof can be exhibited to the maximum.

In addition, according to the invention of claim 2, since the configuration for obtaining the interference area at the time of the work surface change is adopted, the interference is avoided when the work surface change and the tool change are designated in the next step. Tool change at the closest position can be performed. In addition, since the preparation of the next process tool, the tool change, and the change of the workpiece surface are prohibited until the evacuation operation is completed, the reliable operation without interference can be realized.

As described above, the invention described in each claim makes it possible to minimize the time required for indirect work such as tool change and / or change of the workpiece surface in the workpiece processing, so that the workpiece can be efficiently processed.

Claims (2)

The main shaft (M2) by having the main shaft (M2, 21) detachably supporting the tools (M1, 3) to be provided for machining the workpiece in the present step, and rotating the main shaft (M2, 21) in the rotational center in the axial direction And the spindle heads M3 and 5 for processing the work W by rotating the tools M1 and 3 supported by the tool 21, and an accommodating portion 29 for storing the plurality of tools T. Of the plurality of tools (T) in the storage section 29, the civil servants (M5, 7) and the head (M3) for moving the tools (M4, 3 next) to be provided for machining in the next step to a predetermined exchange position. (5) a tool change arm for exchanging the tool (M1, 3) of the current process supported by the current process and the tool (M4, 3 next) of the next process moved to a predetermined exchange position in the tool magazine (M5, 6) ( 9), workpiece peripheral values WT, 13, and 15 for supporting the workpiece W to be machined by the tools M1 and 3 supported by the spindle heads M3 and 5, and the spindle head M3. 5) and workpiece peripherals ( In the machine tool provided with the colum 11 which supports the WT, 13,15 so that it can move relatively to the axial direction of the spindle head M3,5, the present process currently supported by the spindle head M3,5. According to the length of the tool M1, 3 in the axial direction, the length in the axial direction of the tool M4, 3 next of the next step moved to the predetermined exchange position, and the size of the work W. , When the tool is changed by the tool change arm M7, 9, the tool M1, which has the longer length in the axial direction, among the tools M1, 3 in the current step and the tool M4, 3 next in the next step. In order to prevent the tip of 3 or M4,3 next) from interfering with the workpiece W, the height of the closest retraction required between the spindle head M3,5 and the workpiece peripheral devices WT, 13,15 is measured. After completion of processing by the non-interfering closest position calculation means M9, 71, 74, 76 and the current tool M1, 3 supported by the spindle heads M3, 5, the spindle head ( M3,5) and workpiece peripheral device (WT, 13,15) The distance between the spindle heads M3, 5 and the workpiece is driven by driving the separation position changing means M8, 19 so as to take the closest retraction height generated by the non-interfering closest position calculating means M9, 71, 74, 76. Automatic tool change characterized in that it is provided with the closest retraction means (M10, 71, 72, 85) for moving the apparatus (WT, 13, 15) relatively in the axial direction of the spindle head (M3, 5). Numerical Control Machine Tools. The work surface of the workpiece W is changed by rotating the workpiece W around an axis line which is also perpendicular to a plane including an axis line extending in the axial direction of the spindle heads M3 and 5. In the case where tool change and workpiece surface detection are designated in the next step and the surface change means M12, 17, 72, and 15b, the tool change operation and the target avoidance by the tool change arm M7, 9 Between the work W and the tool M1,3 or M4,3 next determined in accordance with the overlap of the work surface change operation of the work W by the work surface changing means M12, 71, 72, 15b. And interfering zone instructing means (M13, 71, 74, 76) for changing the workpiece surface to give data of the interfering zone to the non-interfering closest approach position calculating means (M9, 71, 74, 76). The approach position calculating means M9, 71, 74, 76 is adapted to change the tool change arm M in accordance with the data of the interference area given from the interference area indicating means M13, 71, 74, 76 when the workpiece surface is changed. 7,9), even if the workpiece W is changed by rotating the workpiece W by the workpiece surface changing means M12, 71, 72, 15b. In order that the tip of the tool M1,3 or M4,3 next in the axial direction among the tools M1, 3 and the next tool M4, 3 next does not interfere with the workpiece W, The closest retraction height required between the spindle heads M3, 5 and the workpiece peripheral devices WT, 13, 15 is generated, and the closest retraction means M10, 71, 72, 85 are the spindle head ( After the machining by the tool M1, 3 of the current step supported by M3, 5 is finished, the spindle heads M3, 5 and the workpiece peripheral devices WT, 13, 15 are not in close contact with each other. In order to take the closest retraction height generated by the means M9, 71, 74, 76, the separation position changing means M8, 19 are driven to drive the spindle heads M3, 5 and the workpiece peripheral devices WT, 13, Moving 15) relatively in the axial direction of the spindle heads M3, 5 Automatically numerically controlled machine tool which performs a tool change of.

Images