JPS6044099B2 - Automatic tool size correction method and device for copying machine tools - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention generally relates to the improvement of copying machine tools, and in particular, to machining molds, etc. with complex male and female shapes, while performing automatic tool exchange and achieving high machining efficiency and high machining accuracy. The present invention relates to a copying method which has been improved so as to be able to perform copying, and a copying machine tool with an automatic four-wheel tool changer for carrying out the method.

Generally, in the case of molds for molding or objects whose dimensions are difficult to specify based on drawings, a master mold prepared in advance is traced using a tracer with a contact ball, and the tracer is moved according to the movement of the tracer. A so-called profile slicing machine is used which servo-controls the profile processing operation of a processing tool having a spherical shape corresponding to the contact ball.

In other words, even with numerically controlled machine tools that have recently been significantly developed, it is difficult to program molds etc. due to their complex male and female shapes. is used. However, profiling machine tools such as profiling slicing machines, which have been widely used in the past, generally require a long time and a large amount of cutting to process molds, etc., but they do not automatically change processing tools. A machining method that efficiently progresses copy machining while performing the process has not yet been adopted at all. In the case of copying machine tools, for example, if the automatic tool change mechanism already used in ordinary machining centers is simply applied to automatically change the machining tool, the following problems will occur. It is caused by coming.
Ru. That is, in a copying machine tool, for example, the X. Y. Z
A method is adopted in which the amount of axial movement is controlled and the machining tool is made to copy the workpiece based on this, so a constant relative positional relationship is always maintained between the tracer and the machining tool. If this is not done, accurate dimensions and shape cannot be guaranteed. However, when machining tools are replaced, especially in the case of copy milling machines, it is inevitable that there will be differences in the tool diameter, that is, the radius dimension and tool length of the spherical machining tool. This results in the inconvenience that it is not possible to guarantee that a constant relative positional relationship between the tracer and each processing tool can be maintained. On the other hand, it goes without saying that a copying machine tool has the advantage of being able to automatically change tools and perform all machining tools, from the rough machining process to the finishing machining process, in one step. An object of the present invention is to automatically accomplish tool exchange by dealing with differences in machining processes such as rough machining and finishing machining processes, tool wear, etc., without causing any inconvenience as described above, and to avoid machining errors when exchanging tools. To provide a copying machining method in which the tool diameter and tool length can be corrected according to preset correction amounts in order to always maintain a constant relative positional relationship between the tool and the tracer, The present invention also provides a copying machine tool with an automatic tool changer that can directly implement this method.

In addition, in implementation, only the tool diameter may be automatically corrected, and the tool length may be achieved by manually correcting the tool spindle quill or tracer head of the copying machine tool.
Alternatively, it goes without saying that it is most preferable if both the tool diameter and tool length can be automatically corrected. Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings. The figure is a mechanical diagram showing the overall configuration of a copying machine tool with an automatic tool changer according to the present invention.

In the figure, reference numeral 10 denotes a copying machine tool, which has an upright machine body 11 and a work table 17. A processing tool T is provided in the machine body 11. A tool spindle 12 to which one of the -Tn is attached is provided so as to be slidable in the upward and downward directions by a quill 13. The tool spindle 12 is configured to be rotated by a spindle drive motor 14 after being clamped at a constant height within the quill 13, and the spindle drive motor 14 receives a drive signal from a controller 15 to tool the tool. Main shaft 1
2 at a desired rotational speed. Note that the tool spindle 12 can be slid up and down in small amounts with respect to the quill 13 by manual operation of the handle 21, or automatically by a drive motor 16 such as a pulse motor as described later.
Therefore, the machining tool T is attached to the tool spindle 12. (or T1
~Tn) can be positioned on the table 17 in the upward and downward directions with respect to the workpiece W. As described above, the workpiece W is placed on the table 17, and the mother mold (master) M is also placed on the table 17, and these workpieces W1 mother mold M
The table 17 is placed on the X. ．． Y2
It is movable in the axial direction, and the spindle head 23 is attached to the tool spindle 1.
2 and quill 13 are attached, it can be moved up and down in the Z-axis direction. In this way, the table 17 is arranged at XsY, . It moves relatively in the three Z-axis directions. The movement of this table]7 is controlled by a drive motor 18 which receives a drive servo signal from a well-known copying control device 51.
(equipped with three motors in the X-axis direction, Y-axis direction, and Z-axis direction), and the movement of the table 17 is
For example, the X. sY. ．． It is detected as a machine position signal in the Z3-axis direction and sent to a copying machine tool control device 52, which will be described later.
Now, 30 is a laser part that follows the pattern M on the table 17, and a tracer 31 having a spherical contact that can be normal-displaced according to the shape of the pattern M on the table 17, and the vector normal of the tracer 31. The trace head 32 converts displacement into an electrical signal and sends it out. This tracer section 30
is attached and supported by an arm 24 extending laterally from the spindle head 23. Then, the above-mentioned electric signal generated from the tracer head 32 and indicating the displacement of the tracer 31 is sent to the tracing control device 51. Note that the tracer section 3 consists of a tracer 31 having a spherical probe and a tracer head 32.
As a specific configuration example of 0, a three-dimensional shape measuring device described in Japanese Patent Application Laid-Open No. 49-107558 by the present applicant can be used. Now, in a copying machine tool, when the tracer 31 of the tracer section 30 moves to copy the mother die M, the tracer head 32 moves the tracer 31 by a preset constant amount, that is, the tray which becomes the servo target value in copying control.
Standard displacement position E. As described above, the copying control device 51 sends a drive servo signal to the drive motor 18 of the table 17 to move the table 17 to the X. ,Y. ．． Relative movement corresponding to the shape of the matrix M is given in the three axis directions of Z.
During this time, the processing tool T gripped by the tool spindle 12 is applied to the workpiece W on the table 17. Alternatively, the workpiece W is finished into a shape that matches the shape of the mother die M by cutting at T1 to Tn. In this case, processing tool T is used. −
Both Tn have the same rod and spherical shape as the spherical contact of the tracer 31, and the radial dimension from the spherical center is called the tool diameter, and is usually shaped approximately equal to the radial dimension of the spherical contact of the tracer 31. Ru. Note that the normal vector displacement position detected by the tracer head 32 is sent to the copying control device 51 via the sending section 32''. 33, 34, and 35 each move the tracer 31 of the tracer section 30 to a predetermined position by manual operation. For example, the tracer 31 is used 9 when positioning the master mold M to a copying position.

Reference numeral 50 denotes an operation panel for causing the tracer 31 of the tracer unit 30 to perform a copying operation along the mother die M during copying processing, and is used to set the copying mode, command signals for approach and disapproach between the tracer 31 and the mother die M, or Copying]=Used to manually apply command signals such as starting and stopping the tool spindle 12 of the machine tool 10; therefore, the operation command from the operation panel 50 is applied to the copying machine tool control device 52,
Among these command signals, a copying mode setting command signal and command signals for approach, disapproach, etc. are further sent to the copying control device 51.

That is, the copying machine tool control device 52 forms a central control section of the copying machine tool, in charge of supplying power to various drive motors, etc., and also controls tool exchange according to the present invention and correction operations related thereto, which will be described later. It is something to do. In addition to the general structure of a copying machine tool as described above, according to the present invention, an automatic tool changer 40 is provided on the side surface of the machine body 11 of the copying machine tool 10. A tool change control device 53 is provided to control the tool change operation of the automatic tool change section 40, and receives a tool change command via the copying machine tool control device 52, and also copies a completion signal when the tool change is completed and controls the machine tool control device. 52.

The automatic tool change section 40 is a processing tool T. -T. ．． This magazine device 41 is rotatably provided around a horizontal axis and stores replacement tools,
For example, it also includes means for transporting the illustrated machining tool Tn to a replacement position indicated by a broken line. Replacement processing tool T moved to the replacement position. is a used machining tool attached to the tool spindle 12 which has also been previously lifted from the profiling machining position to the tool exchange position by the well-known tool exchange arm 42;
For example, the processing tool T shown in the figure. is exchanged with That is, the tool exchange arm 42 has tool grips at both ends, as is well known. The tool T is provided with a holding claw that can be rotated around a vertical axis and movable upward and downward. , Tn and then moving it downward. from the tool spindle 12 and the tool Tn from the magazine device 41! Then, the tool Tn is inserted into the tool spindle 12 by rotating 180 times and moving upward again. By returning the tool to the magazine device 41, the tool exchange is completed. This series of tool change operations is started by a tool change start command signal sent from the tool change control device 53 to the automatic tool change section 40 at the tool change time. This is the same as in the case of a machine tool with a device, and when the tool change is completed, a tool change signal is transmitted from the automatic tool change section 40, and at this time, as described above, the tool change control device 53
A tool change completion signal is sent to the copying machine tool control device 52 from there. In the present invention, the tool exchange timing is set by a tool exchange timing signal applied from a tool exchange timing device 54 connected to the copying machine tool control device 52 to the copying machine tool control device 52. The specific configuration of this tool change timing device 54 is as follows: Each machining tool T in the magazine device 41. -T. ．． The machining tool T may be of a type having a built-in timer device that detects the cumulative time of machining operations from the start of the machining operation and notifies the user when the cumulative time predetermined for each machining tool is reached. - The degree of wear and damage of each machining tool is detected from fluctuations in the machining load applied to each machining tool during the Tn profiling operation, and when it reaches a certain level, it is determined that it is time to replace the tool. It may also be of a type that sends out a notification signal. On the other hand, upon receiving the tool change completion signal from the tool change control device 53, the copying machine tool control device 52 pulls down the tool spindle 12 and quill 13 again to the copy machining operation position upon completion of the tool change. That is, a required amount of command pulses are issued to the pulse motor 16 to drive the pulse motor, and the pulse motor 16 is fed to an appropriate feed mechanism (for example, a well-known feed screw mechanism or pinion/rack mechanism) not shown in the drawings. The processing tool Tr. of the tool spindle 12 is connected to the processing tool Tr. is pulled down, and the workpiece W corresponding to the tracer 31 located on the mother mold M is pulled down.
to reach the upper position. Next, the copying machine tool control device 52 further sends a drive signal to the drive motor 14 via the controller 15 to start rotating the tool spindle 12 and restart the copying operation. However, an important feature of the present invention is that at the time of tool exchange and prior to restarting the profiling operation with the replaced new machining tool L, automatic correction of the tool data, namely the tool diameter and preferably the tool length, is performed. It is structured as follows. As mentioned above, in the copying machine tool of this example, the mother die M is placed in the tracer section 30.
As the tracer 31 performs the tracing operation, the three-axis movement of the table 17 is servo-controlled via the tracing control device 51, and at this time, the processing tool gripped by the tool spindle 12 moves against the workpiece W. Since this is a method of performing copy machining and cutting a machined product corresponding to the mother die M, a constant position must always be maintained between the tracer 31 and the machining tool on the tool spindle 12 during the copy machining operation. Otherwise, it becomes impossible to obtain a processed product having exactly the predetermined dimensions and shape. However, when a tool is exchanged, all of the machining tools in the magazine device 41 have completely the same size, that is, the same size. It is impossible to have the same tool diameter and tool length. Therefore, the processing tool T. -Tn
T in order to maintain the relative positional relationship between the tracer 31 and the tracer 31 even when changing tools. From T. ．． It is necessary to correct each machining tool in order to obtain a predetermined relative positional relationship between it and the tracer 31 when it is attached to the tool spindle 12. Therefore, in the present invention, the processing tool T. -Tool data regarding each machining tool (i.e., tool diameter, tool length) in advance when installing the TO in the magazine device 41
When the tool is replaced, the correction amount for the new tool that has been replaced and mounted on the tool spindle 12 is read out and corrected, and after this correction action is completed, the copying machining operation is started. I try to do that. At this time, in the present invention, the tool diameter is corrected at the reference displacement position E of the tracer 31.

This is achieved by changing the . That is,
Reference displacement position E of tracer 31. By changing the servo target value of the copying servo system, it is possible to change the servo target value of the copying servo system, and therefore it is possible to correct the variation in tool diameter. In order to concretely carry out such tool radius correction, a tool data setting device 55 is provided in the present invention, and each machining tool T is set in advance in this device 55. -T. , the reference displacement position E corresponding to . For example, if the correction amount is manually set and the tool data setting device 55 is connected to the copying machine tool control device 52, the copying machine tool control device 52 will be able to change the tool at the tool change time notified by the tool change time control device 54. A tool change command is issued to the tool change control device 53, and the tool data setting device 55 sends a tool change command to the tool data setting device 55 for a machining tool (for example, tool Tn when changing from T to Tn) to be newly mounted on the tool spindle 12. Reference displacement position E that is preset according to the diameter. The correction value is protruded and the reference displacement position E is set in the copying control device 51. A configuration is adopted in which a command is given to change and correct. In addition, the reference displacement position E. As a means of manually setting the correction value of
one for each n in the tool data setting device 55,
Furthermore, by providing each circuit means for A-D conversion and D-A conversion in the copying machine tool control device 52, it is possible to easily adjust the reference displacement position setting circuit of the tracer section 30 provided in the copying control device 51. Reference displacement position E (not shown as it is well known). The changes can be corrected. On the other hand, correction of the tool length is also performed using the tool data setting device 55 for each machining tool T.

The relative positional relationship in the length direction between Tn and the tracer 31 is determined in advance, and the amount to be corrected in length at the time of tool exchange is determined in accordance with this determined relative positional relationship in the length direction. This is set in the tool data setting device 55. If the length correction amount is set in advance in this manner, each machining tool T is controlled by the copying machine tool control device 52 at the same time as the aforementioned tool diameter correction operation. By reading the length correction amount corresponding to -Tn and correcting the amount of drive pulses sent to the pulse motor 16 in accordance with this length correction amount, the length correction regarding the tool length can be achieved. Incidentally, instead of the embodiment shown in the drawings, it is also possible to correct the tool length by applying upward and downward fine movements to the tracer head 32, and in this case, the same A motor and a suitable feeding mechanism may be provided to engage the tracer head 32.
In the above explanation, the tool change timing control device 5 and the tool data setting device 55 are provided to adjust the correction amount of the tool diameter and tool length according to tool change with respect to a copying machine tool having an automatic tool change mechanism. Therefore, although an example of implementation has been described, if a copying machine tool equipped with the copying command storage control calculation means that has already been proposed is equipped with an automatic tool change mechanism, the tool change timing and tool data cannot be changed. It can also be pre-programmed to further improve the automation rate.

As can be understood from the above description, according to the present invention, the present invention is not simply a scale in which a copying machine tool is equipped with an automatic tool changer to automatically change tools; The relative positional relationship between the extremely important tracer for copying the master mold and the processing tool can always be accurately maintained in a predetermined state, making it ideal for processing workpieces such as molds with complex male and female shapes. It is possible to obtain high machining efficiency and high machining accuracy.

[Brief explanation of drawings]

The figure is a mechanical diagram showing the overall mechanism of a copying machine tool with an automatic tool changer according to the present invention.

Claims (1)

[Scope of Claims] 1. In a copying machining method in which a machining tool attached to a tool spindle of a machine body performs a workpiece copying machining operation in accordance with a master pattern copying of a tracer, an automatic tool change mechanism attached to the machine body is provided. The tool is automatically replaced at the tool change time, and the tool data of the processing tool is set in advance, and the tool diameter of the processing tool attached to the tool spindle and the tracer diameter are set in advance. In response to the difference, the reference displacement amount of the tracer is corrected at the tool change time, or in response to the difference between the tool length of the machining tool attached to the tool spindle and the tracer length, the difference between the tool and the tracer is adjusted. An automatic tool size correction method for a copying machine tool, characterized in that the relative length position is corrected at the time of tool exchange, and the tool dimensions are corrected every time the tool is replaced. 2. A copying machine tool that performs a workpiece copying operation on the tool spindle of the machine body by controlling the master pattern copying operation of the tracer by a copying machine tool control means, which is attached to the machine body and has one or more automatic tool change means having a processing tool and a tool change actuation means;
A tool change control means that automatically commands the start of tool change at the tool change time, and a tool change control means that automatically commands the start of tool change at the tool change time, and a tool change control means that performs the copying machining process in advance to correct the reference displacement amount of the tracer in accordance with the difference between the tool diameter of each of the machining tools and the tracer diameter. Automatic tool dimensioning for a copying machine tool, characterized in that the tool diameter correction setting means is configured to set a reference displacement correction amount to the machine control means, and the tool diameter correction is performed automatically in conjunction with automatic tool exchange. correction device. 3. In the automatic tool size correction device for a copying machine tool according to claim 2, the tool diameter correction setting means is an analog or digital means for variably adjusting the gain of the tracer displacement detection output by the copying machine tool control means. Automatic tool size correction device for copying machine tools consisting of: 4. In the automatic tool size correction device for a copying machine tool as set forth in claim 3, the tool diameter correction setting means consisting of the analog means comprises a volume device for manually adjusting an electrical analog output. Automatic tool size correction device. 5. A copying machine tool that performs a workpiece copying operation on a tool spindle of a machine body by controlling the master pattern copying operation of a tracer by a copying machine tool control means, which is attached to the machine body and has one or more automatic tool change means having a processing tool and a tool change actuation means;
A tool change control means for automatically instructing a start of tool change at the tool change time, and a relative length position between the machining tool and the tracer corresponding to the difference between the tool length of each of the machining tools and the length of the tracer. a tool length correction setting means for setting a tool length correction amount in advance in order to keep the tool length constant; A copying machine tool comprising a correction operation actuating means for applying a correction operation to the tracer at the tool exchange time, and configured to perform automatic tool length correction in conjunction with automatic tool exchange. Automatic tool size correction device. 6. In the automatic tool size correction device for a copying machine tool as set forth in claim 5, the correction operation actuating means comprises a motor means for moving the tool spindle of the machine body up and down by a fixed amount. Automatic tool size correction device. 7. In the automatic tool size correction device for a copying machine tool as set forth in claim 5, the correction operation actuating means comprises motor means for moving the tracer up and down by a fixed amount. correction device. 8. A copying machine tool that performs a workpiece copying operation on a tool spindle of a machine body by controlling the master pattern copying operation of a tracer by a copying machine tool control means, which is attached to the machine body and has one or more An automatic tool change means having a processing tool and a tool change operation means, a tool change control means for automatically instructing to start tool change at the tool change time, and a difference between the tool diameter and tracer diameter of each of the above-mentioned processing tools. A tool radius correction setting means for setting a reference displacement correction amount in advance to the copying machine tool control means in order to correspondingly correct the reference displacement amount of the tracer, and a difference between the tool length of each of the processing tools and the length of the tracer. a tool length correction setting means for setting a tool length correction amount in advance to maintain a constant relative length position between the processing tool and the tracer according to the above, and each of the processing tools set in the tool length correction setting means. and a correction operation activation means for applying a correction operation to the tool spindle of the machine body or the tracer at the tool exchange time according to the tool length correction amount. Automatic tool size correction device for machines.