JPH1148072A - Machine tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a machine tool to perform machining of a work and also tool replacement while the spindle heat fitted with a tool is moved between the machining region and replacement region, whereby tool replacement can be performed efficiently. SOLUTION: A timing chart used in a machine tool for performing tool replacement is illustrated in the attached drawing, where the movement of a table (XYB-axis) holding a work is started when the spindle head (Z-axis) has attained the simultaneous motion starting position, so that the table movement is finished at an earlier time than with a conventional machine tool in which the table movement is started when the spindle head has reached the point of origin of the Z-axis. Accordingly the total time required to make tool replacement can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a machine tool which moves a spindle head on which a tool is mounted between a machining area and a change area to machine a workpiece and change a tool, respectively.

[0002]

2. Description of the Related Art Conventionally, there has been known a machine tool capable of performing various kinds of machining by mounting a tool designated by a machining program from a plurality of tools prepared in advance on a spindle. I have.

A machine tool 10 shown in FIG. 7 is one example. The machine tool 10 includes a table 14 for placing a work (not shown) inside a splash guard 12 for preventing scattering of cutting chips, a tool magazine 16 holding tools such as drills and taps, and a machine tool. A main body (hereinafter, also simply referred to as a main body) 28 and the like are arranged. The splash guard 12 has a CRT (Cathode Ray Tube) 20 for displaying the operation status of the machine tool 10, various buttons for giving commands to the machine tool 10, and data such as a machining program for a floppy disk. An operation panel 22 provided with a floppy disk drive or the like for inputting / outputting a work, a work exchange port 24 for entering / exiting and maintaining a work, an inspection hatch 26 used for maintenance and the like are provided.

FIG. 8 shows a side surface around the main body 28. As shown in FIG. 8, the main body 28 includes a spindle head 36 that is moved up and down by rotating a ball screw 34 by a Z-axis servomotor (hereinafter simply referred to as a Z-axis motor) 32 fixed to a column 30, and a frame 38. And a magazine support base 40 fixed to the column 30 through the main body. The tool magazine 16 includes a magazine shaft 42.
Is fixed to the magazine support base 40 so as to be rotatable around.

The spindle head 36 has a spindle for holding tools such as drills and taps, a spindle motor 46 for rotating the spindle, a composite cam body 50, and a ball screw 3.
4 is provided with a feed nut (not shown) screwed to the unit 4 and a clamp / unclamp mechanism (not shown) for detachably holding a tool with respect to the main shaft. The tool magazine 16 has ten grip arms 52 for holding tools.
Are arranged in the circumferential direction, and are swingable by the swing shafts 54, respectively. The grip arm 52 is provided with a cam follower 56 which comes into contact with and separates from the cam surface of the composite cam body 50. The composite cam body 50 is moved up and down together with the main spindle head 36, so that the tool attached to the main spindle is moved. Perform desorption. The tool exchange is performed by rotating the tool magazine 16 by the magazine motor 57. Since this mechanism is described in Japanese Patent Publication No. Hei 7-22860, only the outline thereof will be described here.

FIG. 9 schematically shows a tool changing process. After drilling a workpiece 60 using a tool 58 as shown in the lower left of FIG. Shows how to replace it. To do this, first
The tool 58 is removed from the workpiece 60 by operating the shaft motor 32 and raising the spindle head 36. This moving distance changes depending on the length of the tool 58, the height of the work, and the like.
Next, the rotation of the spindle motor is stopped, and Z
Activate the axis motor 32 and move the spindle head 36 to the Z-axis origin ZO.
(This is called Z-axis return to origin). In the Z-axis origin ZO, an arbitrary work is fixed to the table 14,
Even if the table 14 is moved while any tools (not limited to the tools 58 and 58 ') are attached to the main shaft,
The Z-axis position at which the tool and the workpiece 60 do not collide with each other (however, only when a workpiece having a size that meets the specifications of the machine tool 10 and a usable tool are used).

When the tool 58 is moved up to this point, the table 14 is moved so that the position where the tool 58 'is processed on the workpiece 60 is directly below the spindle, and the spindle head 36 is raised to the ATC origin.
The ATC origin is set further above the Z-axis origin ZO. While the spindle head 36 is being raised to this point,
When the grip cam 52 is swung by the composite cam body 50 and the clamp / unclamp mechanism unclamps the tool 58, the tool 58 is detached from the spindle. When the spindle head 36 reaches the ATC origin, the tool 58 Is held by the grip arm 52. Then, the tool magazine 16 is rotated to position the grip arm 52 holding the tool 58 'below the main shaft. In this figure,
For convenience, the spindle head 36 is shown as moving in the horizontal direction, but actually moves only in the vertical direction. Then, the spindle head 36 is lowered to the Z-axis origin ZO. During this lowering, the tool 58 'is mounted on the spindle by the clamp / unclamp mechanism clamping the tool 58'. Then, the spindle motor is operated, and the spindle head 3
6 is lowered to a height determined by the length of the tool 58 'and the height of the workpiece 60.

FIG. 1 is a timing chart of this.
0. In this figure, the horizontal axis represents time, and the vertical axis represents the rotation speed of each motor. In the figure, the drive related to the movement of the table 14 is indicated by the XYB axis. Actually X
The (left-right direction) axis, the Y (front-back direction), and the B-axis (rotation about the left-right direction) are performed independently, but in the figure, the three are integrated and described as XYB axes.

[0009]

As can be seen from the timing chart of FIG.
There is a dead time TD after 6 is lowered to the Z-axis origin ZO. This is the time to wait for the movement of the XYB axes to be completed. This time increases as the distance between the position where the machining is performed by the tool 58 and the position where the machining is performed by the tool 58 'increases, resulting in inefficient tool change.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and the present invention according to claim 1 shortens the time required for tool change by shortening the dead time TD, thereby realizing the efficiency of the entire machining. The purpose is to do. Another object of the present invention is to make it possible to further reduce the processing time according to the present invention.

Still another object of the present invention is to reduce the processing time by a method different from that of the present invention. The fourth object of the present invention is to make it possible to further reduce the processing time according to the third aspect of the present invention.

[0012]

Means for Solving the Problems and Effects of the Invention In order to achieve the above object, a machine tool according to claim 1 of the present invention is a spindle head for processing a workpiece by rotating a mounted tool. A spindle head moving means for moving the spindle head between a machining area for machining a workpiece and an exchange area for exchanging a tool mounted on the spindle head; a table for holding the workpiece; the table and the spindle Relative movement means for relatively moving the heads relative to each other at least in a direction perpendicular to the rotation axis of the tool, and exchange means for exchanging a tool mounted on the spindle head moved to the exchange area with a tool to be used next When the instruction to operate the exchange means is given in a program created in advance, the spindle head is moved from the machining area to the machine tool. A retracting means for moving the relative moving means in the direction of the rotation axis up to an origin, which is a point at which the relative moving means can be driven without interfering with any work that can be a processing target. When the head is retracted, at least the spindle head and a tool mounted on the spindle head can drive the relative moving unit without interfering with the work held on the table, and the spindle head is retracted. A movement start position input means for inputting a movement start position which is a position, a spindle head position detection means for detecting a position of the spindle head moved by the retreating means, and the spindle head is moved to the movement start position. When the evacuation is detected by the spindle head position detecting means, the driving of the relative moving means is started, and the program Based on the beam,
Relative movement start means for relatively moving from the current position of the table to a position where processing is performed using a tool to be used next.

Here, the origin corresponds to the Z-axis origin ZO of the machine tool 10, the machining area corresponds to a portion below the Z-axis origin ZO, and the exchange area corresponds to the Z-axis origin ZO of the machine tool 10. Above. Some machine tools other than the machine tool 10 perform tool change at the origin. In such a machine, the origin is the exchange area.

Processing of the spindle head moving means is performed by the machine tool 1
0, the Z-axis motor 32 corresponds to the process of reciprocating between the Z-axis origin ZO and the ATC origin in the process.
This corresponds to a process of raising the spindle head 36 to the axis origin ZO. As described above, in the machine tool 10, both the processing of the spindle head moving means and the processing of the retraction means are performed by driving the Z-axis motor 32. Is located along the rotation axis. In a machine tool in which the exchange area is located on the side of the machining area or the like, the spindle head is moved in that direction by another motor or the like, and this processing is processing as spindle head moving means.

The exchange means corresponds to the tool magazine 16, the composite cam body 50, the cam follower 56, and the like. The relative movement means moves the table 14 in each of the X, Y, and B axes (the B axis). In this case, it corresponds to a drive motor for rotating the motor. The present invention is also directed to a machine tool in which a work is fixed to a machine tool, and a desired position of the work is machined by moving a spindle head in a direction other than the direction along the rotation axis. However, hereinafter, unless otherwise specified, a description will be given using a type such as the machine tool 10 described above.

In the machine tool constructed as described above, the retreating means retreats the spindle head each time the tool is exchanged by the exchanging means (corresponding to the above-described process). Is started when the spindle head position reaches. The movement start position is input via the movement start position input means, and when the movement start position is reached, the relative movement start means relatively moves the table to a position where processing is performed using a tool to be used next. . The position of the spindle head is detected by a spindle head position detecting means.

The difference between the origin and the movement start position is as follows.
In the latter case, the work held on the table and the tool mounted on the spindle head do not interfere with each other, while the arbitrary work and any tool are at the position of the spindle head that does not interfere with each other. It is the position of the spindle head.

In such a machine tool, if the movement start position is set closer to the machining area than the origin, the table starts relative movement at a point before the spindle head reaches the origin. For this reason, even when the table is moved so that the relative movement cannot be performed within the operation time of the exchange means alone (corresponding to time A in FIG. 10), compared with the conventional case where the relative movement is started after reaching the origin. , The relative movement is completed earlier.

Thus, according to the machine tool of the first aspect, the movement of the table is started before the raised spindle head reaches the origin, so that the movement is terminated at an early time. Can be. And this gives
Since the lowering of the spindle head corresponding to the above-described process can be started at an early point in time, the time required for tool change can be reduced.

If the machine tool according to the first aspect is specialized for a work fixed to the table and a tool mounted on the head, the machine tool does not interfere with each other even when the table is moved (ie, the movement start position). ) Can be shifted to the machining area side from the origin, but if it is specialized for the work immediately before the tool change, there is a possibility that it can be further shifted to the machining area side. For example, in the above-described machine tool 10, when processing a workpiece having a stepped upper surface, the lower the surface, the lower the movement start position may be. The machine tool according to claim 2 utilizes this.

That is, in this machine tool, machining is performed using the next tool from the relative position of the table immediately before the exchange in response to the instruction to operate the exchange means indicated in the program. A retreat position of the spindle head up to a relative position is set in advance, and this retreat position is set as a movement start position.

In this way, in the above-described work having a stepped upper surface, when the same surface is to be machined with two or more types of tools, a movement start position specialized for that surface is set in the program. By doing so, the movement start position can be set to a position closer to the work, thereby further reducing the time required for tool change. In addition, when the height of the machining point changes before and after the tool change, it is often necessary to set the movement start position with reference to the higher surface. If the program is programmed so that the time to reach the movement start position can be made earlier, the time required for the tool change can be reduced.

If a program for processing such a workpiece is prepared so as to process from a high surface to a low surface, it is expected that the processing operation will be performed more efficiently. The tool head is moved from the exchange area to the machining area in order to perform machining using the tool when the exchange of the tool in the exchange area is completed. Will be. At this time, if the movement of the spindle head is controlled as in the machine tool according to the third aspect, machining can be resumed at an early point.

That is, in the machine tool according to the third aspect, when the spindle head whose tool has been replaced approaches the workpiece instead of the movement start position input means in the machine tool according to the first aspect, At least the spindle head and the tool mounted on the spindle head, the approach position of the spindle head capable of driving the relative moving means without interfering with the work,
And an approaching position inputting means for inputting a command, and, in place of the retreating means, an approaching means for moving the spindle head to the approaching position when the replacement by the replacing means is completed. Processing start means for moving the spindle head to a position at which the work can be processed when the movement of the table by the necessary relative moving means is completed and the spindle head is moved to the approach position by the approach means. Has become.

If the machine tool according to the third aspect does not include the relative movement start means, the relative movement of the table is started when the spindle head is moved from the machining area and reaches the origin. Therefore, the time when the relative movement is completed is not different from the conventional machine tool. However, if the approach position is set closer to the workpiece than the origin via the approach position input means, the approach means moves the spindle head to this approach position, so the machining start means moves the spindle head accordingly. The amount to be reduced is reduced, and processing is started at an early point.

Therefore, according to the machine tool of the third aspect, it is possible to reduce the time from the interruption of the machining for the tool change to the resumption of the machining. Note that the approach position input means, approach means, and processing start means are described as configurations that replace the movement start position input means, retreat means, and relative movement start means, respectively, but the retreat means retracts the spindle head to the origin. In order to perform this, it is usually provided with a movement start position input unit and a relative movement start unit. When these are provided, the time point at which the movement of the table is completed is also advanced, so that the time point at which the processing is resumed can be further advanced.

According to the present invention described in claim 2,
If the work is specialized for the work immediately after the tool change, there is a possibility that the approach position can be further shifted to the machining area side. This may be achieved by a machine tool according to the fourth aspect. That is, in the machine tool according to the fourth aspect, the approach position of the spindle head at the relative position where the machining is performed using the tool to be used next is determined in response to the instruction to operate the exchange means indicated in the program. Set in advance.

In this way, in the case of the above-described work having the step-like upper surface, when the processing portion is moved from a high surface to a low surface before and after the tool change, the approach position can be made closer to the low surface. The point at which the processing start means restarts the processing can be advanced.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A machine tool to which the present invention is applied will be described below with reference to the drawings. The appearance is the same as that of the machine tool 10 described above, so that the illustration is omitted, and the same reference numerals are given to the same components as those of the machine tool 10.

FIG. 1 is a block diagram showing a control device 70 that controls the entire control of machining in the machine tool 10. As shown in FIG. The control device 70 includes a master CPU 71 that controls the entire control and a slave C that mainly controls the processing of the work 60.
PU72 and ATC unit CPU73 that manages tool change
It is configured around one CPU.

The master CPU 71 has a master ROM 74 for storing programs and constants for operating the control device 70 itself, a first RAM 75 for temporarily storing variables, flags, and the like during execution of control. A second master RAM 76 which stores a machining program for instructing a tool or the like to be used for workpiece machining.
, The CRT 20 and the operation panel 22 are connected. The second master RAM 76 has a backup function so that the stored contents are not erased even when the power is turned off.

The slave CPU 72 has a slave ROM 77 for storing a motor drive program and constants for work machining, a slave RAM 78 for temporarily storing variables and flags during execution of work machining control, and a table 1.
An X-axis motor 84 that moves the X-ray 4 in the X-axis direction, a Y-axis motor 86 that moves the Y-axis in the Y-axis direction, a B-axis motor 88 that rotates around the B-axis, the Z-axis motor 32, and the main shaft motor 46 are connected. The slave CPU 72 controls and drives them, and executes machining of the work 60 held on the table 14 by a predetermined tool.

The ATC CPU 73 has an ATC ROM 79 for storing a magazine turning program and constants for tool change, an ATC RAM 80 for temporarily storing variables, flags, and the like during execution of tool change control, and a magazine motor 5.
7 are connected. The ATC unit CPU 73 controls and drives the magazine motor 57 to rotate the tool magazine 16 to determine the next tool to be used.

Master CPU 71 and slave CPU 72
In the meantime, the master CPU 71
An inter-MS common RAM 81 for exchanging a command to the MS or a signal in the opposite direction and other information is connected. Information is written to and read from the MS-to-MS common RAM 81 from both the master CPU 71 and the slave CPU 72.

The master CPU 71 and the ATC unit CPU
Between 73, the master CPU 71 to the ATC unit CPU
A common RAM 82 between MAs for exchanging a command to 73 or a signal in the opposite direction and other information is connected. Like the inter-MS common RAM 81 described above, the inter-MA common RAM 82 includes a master CPU 71 and an ATC unit CP.
Information is written or read from both sides of U73.

The master CPU 71 temporarily stores the machining programs and parameters read from the floppy disk drive of the operation panel 22 in the second master unit RAM 76. The stored machining program can be confirmed by displaying it on the CRT 20 as shown in FIG. The parameter is a group of items for setting the operation of the machine, and can be confirmed by displaying it on the CRT 20 as shown in FIG. Then, the master CPU 71 generates various commands based on these machining programs and parameters, and outputs
U72 issues an operation command to the ATC unit CPU73.

FIG. 4 shows how the tool is changed in the machine tool 10 having the above-described configuration. This drawing corresponds to FIG. 9 and shows a state in which, after drilling a workpiece 60 using a tool 58, the tool 58 is replaced with a tool 58 ', similarly to FIG.

To do this, first, a common RAM between MSs
The Z-axis motor 32 is operated by issuing a command to the slave CPU 72 via 81, the spindle head 36 is raised, the tool 58 is removed from the work 60, and once the spindle head 3
6 is stopped. Next, at step (1), the spindle motor 46 is stopped, and the Z-axis motor 32 is operated again.
6 is raised to the simultaneous operation position. At this time, the simultaneous operation position corresponds to the movement start position of the present invention. That is, the simultaneous operation position is determined by the work 6 fixed to the table 14.
0, and the tool 58 mounted on the spindle,
Even when the table 14 is moved, these are positions on the Z axis where they do not interfere with each other, and are given as one of the parameters. Therefore, in order to input the simultaneous operation position, a screen for inputting the simultaneous operation position as shown in FIG.
2 to input the simultaneous operation position. This processing corresponds to the movement start position input means of the present invention (as described later,
Since the simultaneous operation position also corresponds to the approach position of the present invention, this processing also serves as the approach position input means.) Whether the spindle head 36 has reached the simultaneous operation position is determined by the position of the spindle head 36 calculated by the slave CPU 72 based on the count value output from the rotary encoder of the Z-axis motor 32 in the inter-MS common RAM 81. It is determined by comparing with the simultaneous operation position which is received by the master CPU 71 and input in advance as one of the parameters. In other words, the slave CPU 72 when calculating the position of the spindle head 36 based on the count value output by the rotary encoder of the Z-axis motor 32 corresponds to the spindle head position detecting means of the present invention.

Then, a command is issued to the slave CPU 72 through the inter-MS common RAM 81 at X, thereby
The axis motor 84, the Y-axis motor 86, and the B-axis motor 88 are appropriately driven to start the movement of the table 14, and the spindle head 36 is raised to the ATC origin. 9, when the spindle head 36 is raised to the ATC origin, the tool 58 is removed from the spindle and is held by the grip arm 52 for the tool 58. Then, by issuing a command to the ATC unit CPU 73 via the common RAM 82 between MAs, the magazine motor 57 is driven to rotate the tool magazine 16, and the grip arm 52 holding the tool 58 'is positioned below the main shaft. Then, when the spindle head 36 is lowered to the simultaneous operation position, a tool 58 'is mounted on the spindle during the lowering. At this time, the simultaneous operation position corresponds to the approach position, and the process of lowering the spindle head 36 to the simultaneous operation position corresponds to the approach means of the present invention. Then, the spindle motor 46 is driven at ′, the spindle head 36 is lowered, and machining using the tool 58 ′ is started. That is, 'corresponds to the processing start means of the present invention.

FIG. 6 is a timing chart showing this process according to FIG. As shown in the figure, in the machine tool 10, when the spindle head 36 (Z-axis) reaches the simultaneous operation position before reaching the Z-axis origin ZO, the table 14 (XYB axis) starts moving. To do
The movement of the table 14 ends earlier than that shown in FIG. 10 (other conditions are assumed to be the same). Therefore, the dead time TD is reduced, and the total time required for tool change can be reduced. Under the conditions shown in this figure, since the driving of the XYB axes happens to be completed at the same time when the spindle head 36 descends and reaches the simultaneous operation position, the time TD is zero. When the moving amount of the data is larger, a time TD occurs. In this case as well, the time required for ′ can be reduced as compared to the case shown in FIG.

Whenever the machining program to be executed is changed, the screen shown in FIG. 5 is displayed on the CRT 20 and the simultaneous operation position is input, so that the simultaneous operation position suitable for each program can be set. In addition, in ', the Z axis is AT
To reciprocate between the C origin and the simultaneous operation position lower than the Z-axis origin ZO, the time A ′ required for this is longer than the time A shown in FIG. 10, but ″ becomes shorter accordingly. Therefore, the time from 'to' is shortened by the time TD.

As described above, the machine tool 10 has been described as an embodiment of the present invention, but the present invention is not limited to such an embodiment, and can be implemented in various modes. For example, as shown in FIG. 6, in the machine tool 10, the spindle head 36 is temporarily stopped at the simultaneous operation position and raised to the ATC origin, but the spindle head 36 is moved up to the conventional position shown in FIG. 10. It may be raised to the origin like the machine tool 10. The position of the spindle head 36 is monitored almost constantly, and when the simultaneous operation position is reached, by moving the table 14, the tool change time can be reduced in the same manner as described above.

The table 14 may be configured to be able to move (or rotate) about axes other than the X, Y, and B axes. Even in this case, the work,
If the optimal simultaneous operation position is set in accordance with the tool to be used and the machining program, the time required for tool exchange can be reduced as compared with a machine tool in which the table cannot be moved until the spindle head 36 reaches the origin.

In this embodiment, the simultaneous operation position is input as one of the parameters, but may be set in the machining program. Particularly in this case, there is a possibility that the processing time can be further reduced for the following reasons. In other words, the optimal simultaneous operation position differs depending on the upper surface position of the workpiece at the time of tool change and the tool to be changed,
This is because the simultaneous operation position may be set at a lower position. For example, if the optimal simultaneous operation position is set for each tool change command in the machining program, the movement of the table 14 can be started at an earlier point in time, and the table 14 can be moved without generating the dead time TD. You can move it for a long distance.

Although the movement start position and the approach position are set to the common position as the simultaneous operation positions, they may be set to different positions. As the way of inputting these, it is conceivable to give them as parameters as described above, or to set the movement start position and the approach position for each tool change command in the machining program. In the latter case, if the stepped workpiece is machined from the high side to the low side, the time required from the interruption of machining due to tool change to the restart of machining will be shortened each time the machining is changed. (Except when all tool changes are made on one surface).

When the length of the tool is increased in order of length for a workpiece having a uniform height, the same effect can be obtained as in the case of processing a step-shaped workpiece in order from a higher surface. In view of using such tools having different lengths, the reference position of the tool may be set to the tip of the tool. That is, FIG.
In the explanatory diagrams shown in FIGS. 9A and 9B, the tip of the tool is used as a reference instead of the base of the tool. If the length of the tool is previously taught to the machine tool, and the tip of the tool is brought to the simultaneous operation position (movement start position, approach position), these positions can be set only from the shape of the work. become.

The present invention may be applied to a machine tool other than the type shown in FIG. 7 in which the tool is changed by the approach and separation of the spindle head 36 from and to the tool magazine 16. For example, the tool magazine moves up and down together with the spindle head, and both the tool and the tool exchange tools at a position where they do not interfere with the work (that is, the exchange area of the present invention). In the machine tool for positioning the machining position, or by a spindle head configured in the form of a manipulator, the stock is stored at another location in the machine tool (this area corresponds to the exchange area of the present invention). The present invention may be applied to a machine tool that takes out a tool, rotates the tool, and performs machining. In any machine tool, the machine tool 10
Similarly to the above, when the spindle head retreats to a position where relative movement is possible without interfering with the table each time a tool change is made, if the relative movement is started, the time for tool change can be reduced, and the relative movement can be reduced. If the spindle head can be approached to the approach position during this time, the start of machining can be advanced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a control device of a machine tool to which the present invention is applied.

FIG. 2 is an explanatory diagram showing a state in which a part of a machining program is displayed on a CRT 20.

FIG. 3 is an explanatory diagram illustrating a state in which some of the parameters are displayed on a CRT 20;

FIG. 4 is an explanatory view schematically showing how a tool change is performed in a machine tool to which the present invention is applied.

FIG. 5 is an explanatory diagram showing a screen displayed on the CRT 20 when a simultaneous operation position is input.

FIG. 6 is a timing chart when a tool change is performed in a machine tool to which the present invention is applied.

FIG. 7 is an external view showing an example of a conventional machine tool.

FIG. 8 is a side view showing a state near a main body 28 in a conventional machine tool.

FIG. 9 is an explanatory diagram schematically showing how a tool change is performed in a conventional machine tool.

FIG. 10 is a timing chart when a tool change is performed in a conventional machine tool.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Machine tool 14 ... Table 16 ... Tool magazine 22 ... Operation panel 32 ... Z-axis motor 36 ... Spindle head 46 ... Spindle motor 48 ... Composite cam body 50 ... Composite cam body 52 ... Grip arm 54 ... Swing axis 56 ... Cam follower 57: Magazine motor 58: Tool 60: Workpiece 70: Control device 84: X-axis motor 86: Y-axis motor 88: B-axis motor A: time TD: dead time ZO: Z-axis origin

Claims (4)

[Claims] 1. A spindle head for machining a workpiece by rotating a mounted tool, and a machining area for machining the workpiece and an exchange area for exchanging a tool attached to the spindle head. A spindle head moving means for moving, a table for holding a work, a relative moving means for relatively moving the table and the spindle head relative to each other at least in a direction perpendicular to the rotation axis of the tool, Exchange means for exchanging a tool mounted on the spindle head for a tool to be used next, and when the instruction to operate the exchange means is given in a previously created program, the spindle head is processed by the machining. From the region, to the origin, which is a point at which the relative movement means can be driven without interfering with any work that can be a processing target of the machine tool, A retracting means for moving in the rotation axis direction, when the spindle head is retracted by the retracting means,
At least the spindle head and the tool mounted on the spindle head do not interfere with the work held on the table, and the movement start position, which is the retreat position of the spindle head, at which the relative movement means can be driven, Movement start position input means for inputting; spindle head position detection means for detecting the position of the spindle head moved by the retreat means; and that the spindle head has retreated to the movement start position, When detected by the position detecting means,
Relative movement start means for starting driving of the relative movement means and performing relative movement from a current position of the table to a position where processing is performed using a tool to be used next, based on the program. A machine tool characterized in that: 2. The method according to claim 1, wherein the movement start position input means sets the movement start position from a current relative position of the spindle head and the table to a relative position at which machining is performed using a tool to be used next. , At least the spindle head and a tool mounted on the spindle head do not interfere with the work held on the table, the retracted position of the spindle head at which the relative movement start means can be driven, In the program, the setting is performed for each instruction to operate the exchange means, wherein the relative movement start means performs the machining by the spindle head in response to the instruction to operate the exchange means. Retreating from the area and reaching the movement start position set in the program in response to the instruction, the spindle head position detecting means More is detected, the machine tool of claim 1, wherein said one starts driving the relative moving means is. 3. A spindle head for processing a workpiece by rotating a mounted tool, and a machining area for processing the workpiece and an exchange area for exchanging a tool mounted on the spindle head. A spindle head moving means for moving, a table for holding a work, a relative moving means for relatively moving the table and the spindle head relative to each other at least in a direction perpendicular to the rotation axis of the tool, Exchange means for exchanging a tool mounted on the spindle head for a tool to be used next, when the spindle head whose tool has been exchanged by the exchange means approaches the work. At least the spindle head and the tool mounted on the spindle head do not interfere with the work held on the table. Approach position input means for inputting an approach position of the spindle head capable of driving relative movement means, and approach means for moving the spindle head from the exchange area to the approach position when the exchange by the exchange means is completed. When the relative movement by the relative moving means necessary for tool exchange is completed and the spindle head is moved to the approach position by the approaching means, the spindle head can be moved to a position where the work can be processed. A machine tool comprising: a machining start means for moving the machine tool to 4. The approach position input means, as the approach position, at least at the spindle head and a tool mounted on the spindle head at a relative position where processing is performed using a tool to be used next. Setting a position that does not interfere with the work held on the table for each instruction to operate the exchange means in the program, wherein the approaching means operates the exchange means. When the tool is replaced in response to the instruction, the spindle head approaches the work from the replacement area to the approach position set in the program in response to the instruction. The machining start means completes the movement of the table by the relative movement means required in accordance with the tool change, and the spindle head is moved by the approach means. When the spindle head is moved to the approach position set in the program in response to an instruction to operate the exchange means, the spindle head is moved to a position at which the work can be processed. The machine tool according to claim 3, wherein