JPH0698567B2 - Free curved surface processing machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a free-form surface processing machine that realizes a desired three-dimensional free-form surface by machining, and in particular, the freedom to achieve complete automation without manpower. The present invention relates to a curved surface processing machine.

[Prior Art] Conventionally, mechanical processing such as mold making, which requires high accuracy for a three-dimensional free-form surface, is performed by the manual work and intuition of an expert, and requires a lot of time and labor. For example, after performing only rough engraving with a processing machine or the like, rough finishing is performed with a hand-held grinder, and then grinding and polishing are performed using a grindstone or the like depending on the sense of touch and visual sense of an expert. Therefore, in recent years, a three-dimensional free-form curved surface grinder has been developed for the purpose of mechanization of the above-mentioned manual work. This kind of equipment is intended to achieve the desired work by knowing the contents of the grinding work by constant pressure self-guided copying or by teaching teaching by copying a typical work point. However, it is necessary to manually input information on the machined surface by manually teaching the working point.

[Problems to be Solved by the Invention] Accordingly, the above-described conventional processing of a three-dimensional free-form surface has the above-mentioned problems.

First, the grinder using the constant pressure self-guided copying can grind the machined surface to a certain degree of roughness, but can grind only according to the shape of the pre-machining, and finally requires the work of the skilled person. That is, the effect is that the time required for the work can be shortened to some extent.

Further, in a grinder in which the work content is taught by teaching, there is a problem in using it for high-mix low-volume production due to the complexity of manually teaching a typical work point for each work.

Furthermore, both of the above grinding machines have low degrees of freedom in the grinding machines,
For example, it is necessary to chuck a work piece many times to perform grinding of one work piece, productivity is low, and complete automation cannot be achieved.

In other words, all the conventional processing machines are open controls with a low degree of freedom, are not sufficient in terms of application to the liberalization, processing accuracy, etc., and cannot comply with today's automation.

The present invention has been made in view of the above problems, and provides an excellent free-form surface processing machine capable of performing desired machining quickly and accurately over all three-dimensional free-form surfaces with one work chuck. It is an object.

[Means for Solving Problems] Means configured according to the present invention for solving the above problems are as follows.
As shown in the basic configuration diagram of FIG. 1, the finish three-dimensional curved surface shape, which is the target shape of the work, is determined based on the data and stored, and after the work is cut, the shape is formed by grinding. In a free-form surface processing machine to be performed, a processing unit that moves a processing tool to an arbitrary position on the work under predetermined processing conditions and changes a processing amount of the processing tool with respect to the work in order to realize the target shape of the work. C1, a workpiece relative shape measuring means C2 for measuring a relative shape of the workpiece in a processing range during grinding by the processing means C1, a relative shape of the workpiece measured by the workpiece relative shape measuring means C2 and the workpiece Processing condition changing means C3 for changing the processing conditions of the processing means C1 by comparing with the target shape of
A workpiece absolute shape measuring means C4 for measuring the absolute shape of the workpiece machined by the machining means C1, and comparing the absolute shape of the workpiece measured by the workpiece absolute shape measuring means C4 with the target shape of the workpiece. And a machining shortage amount calculating means C5 for calculating a machining shortage amount, and a reworking control means for performing reworking when the machining shortage amount calculated by the machining shortage amount calculating means C5 is equal to or more than a predetermined value.
The gist is a free-form surface processing machine that is equipped with C6 and.

[Operation] The present invention is an apparatus for cutting and grinding a work to form a work having a desired three-dimensional curved surface, and the final shape (target shape) of the work is, for example, a known memory element. Remembered

In addition, since the shape memory usually has a huge amount of information, the shape of the work is designed in advance by CAD (Computer Aided Design) in order to store the shape more accurately and quickly. It is preferable to configure a data flow such as directly writing) to a ROM or the like.

The processing means C1 in the present invention changes the shape of the work, and therefore has the ability to move the processing tool that changes its shape to an arbitrary position on the work and the ability to control the operation of the processing tool. For example, when only slightly machining the shape of the work, move the processing tool such as the grindstone to the predetermined position of the work and change the rotation speed of the grindstone or the pressing pressure to operate the grindstone or the like with respect to the work. What is controlled corresponds to the processing means C1.

Further, since the processing means C1 has the ability to move the processing tool to an arbitrary position on the work, the portion for holding the processing tool, so-called arm or head has three-dimensional freedom. For example, in order to move the processing tool, the X axis, the Y axis, the Z axis, the contact angle control axis A axis, and the C axis 5
A moving mechanism that can freely control the axis is adopted.
Furthermore, in order to change the amount of processing performed by the processing tool,
It is preferable that one axis of the pressing force control axis of the processing tool can be controlled, and a 6-axis processing means in combination with the control axis for movement is a more preferable aspect. Further, it is preferable that the processing tool itself to be held is selected and changed as a means for changing the processing amount. That is, when the machining amount is coarse and large, a dedicated tool such as grinding can be selected, and when the machining amount is small and small, a dedicated tool such as polishing can be selected. This can be constituted, for example, by a known automatic tool change.

The workpiece relative shape measuring means C2 measures the three-dimensional curved surface shape in the machining execution range of the workpiece. For this, for example, shape recognition devices such as shape sensors such as various cameras currently provided can be used. That is, when grinding or the like is performed and a large change is caused in the shape of the work, it is always necessary to absolutely detect the shape of the entire work. Therefore, the absolute shape measuring unit is indispensable, but in order to know how much shape change occurs in the part where grinding is actually performed in real time and to know the usage status of the grinding tool, etc. It is sufficient to detect changes in relative shape. That is, real-time detection is simple and effective for detecting that the grinding ability is deteriorated due to clogging or wear of the grinding tool. It should be noted that in the polishing process for producing a simple surface accuracy without changing the shape of the workpiece, rather than performing an absolute shape detection that requires time for detection, a method of performing a simple partial or relative shape detection Is preferable from the viewpoint of improving workability.

The machining condition changing means C3 means the machining means according to the machining state measured by the workpiece relative shape measuring means.
The conditions for processing by C1 are changed. Specifically, for example, the grinding condition is changed (for example, pressing force of the grinding device) based on the relative shape measured in real time during grinding so as to always maintain the optimum grinding state. As a result, even if the grinding ability is lowered due to clogging or wear of the grinding tool during grinding, the compensation can be promptly performed.

The work absolute shape measuring means C4 measures the absolute three-dimensional curved surface shape of the work over the entire work. For this, for example, various shape recognition devices such as a three-dimensional shape measuring machine having a head that can freely move in the X, Y, and Z directions and having a distance sensor at its tip can be used. This is because, as described above, when the grinding or the like is executed to cause a large change in the shape of the work, it is always necessary to absolutely detect the shape of the whole work.

The machining shortage amount calculation means C5 compares the detection information of the work absolute shape measurement means C4 with the information of the target shape of the work. By comparing these two pieces of information, the difference between the finished shape and the actual shape, that is, the amount of machining shortage currently required is found.

The reprocessing control means C6 controls the processing means C1 according to the processing shortage amount found as described above. In other words, the processing amount C1
To execute. Therefore, for example, if the amount of machining shortage is extremely large and a rough product is required,
The processing means C1 is caused to select a coarse grindstone or a grinder (which can realize a large processing amount), and sends a control signal to increase the pressing pressure and the rotation speed. In this way, the present rework control means C6 appropriately performs centralized management of the control amount in order to operate the various means described above more efficiently. Due to the progress of computer technology in recent years, it is preferable in terms of accuracy and processing speed to use this computer as the rework control means C6 and numerically control each of the above means.

Hereinafter, in order to describe the present invention more specifically, examples will be described in detail.

[Embodiment] FIG. 2 is an explanatory view schematically showing the free-form surface processing machine of the embodiment for each function.

In FIG. 2, reference numeral 1 denotes a so-called gate-type processing machine main body, and a beam 5 movable in the up-and-down direction (hereinafter referred to as the Z direction) is bridged over the gate-shaped support portion 3 so as to wrap the beam 5. A head 7 is provided. Further, the head 7 can freely move on the beam 5 and can move to any position in the vertical direction of the paper (hereinafter referred to as Y direction). Further, the pallet 11 on which the work 9 is placed can be moved by the moving table 13 in the front-back direction of the paper (hereinafter referred to as the X direction). With the above-described components, the free-form surface processing machine of this embodiment can achieve X, Y and Z 3-axis free operation.

Further, when the head 7 moves to the right on the beam 5 and reaches an automatic attachment changer 15 (hereinafter referred to as AAC) installed next to the gate-shaped support column 3, the attachment 17 most suitable for various processes is attached. To be Similarly, a tool held by the attachment 17, such as a grindstone or a grinder, is an automatic tool changer 19 (hereinafter referred to as ATC) which is attached to the side of the column 3 by moving the head 7 with the attachment 17 leftward on the beam 5. When it reaches), it will be automatically replaced with the best one. twenty one
Has a head 23 that can move freely in X, Y, and Z directions with a gate-shaped device like the main body of the processing machine, and three-dimensionally measures the shape of the work 9 having a distance sensor 25 at its tip This is a shape measuring machine. The shape measuring machine 21 and the processing machine main body 1 are connected to each other online by the moving table 13 described above, and constitute a so-called automatic pallet changer (hereinafter referred to as APC). 27 and 29
Is a controller composed of computers that mutually perform information communication, and controls the above-mentioned movement amounts of the three axes and controls the ATC 19, AAC 15 and moving table 13, respectively. The controllers 27 and 29 also perform updating with external devices and form a closed loop with the external devices.

Details of the attachment 17 will be described with reference to the explanatory view of FIG. As shown, this embodiment has a special grinding / measuring tool 30. This grinding and measuring tool
Although 30 is held by the attachment 17, the contact angle with respect to the work 9 is freely changed by the operation of the attachment 17 (by driving in the A-axis and C-axis directions in the figure). The grinding / measurement tool 30 is shown with a roughing grindstone 31 attached as an example. The grinding and measuring tool 30 has a simple shape sensor 33 on its side wall. This is, for example, a work 9 to be ground by a roughing grinding wheel 31.
The grinding condition on the surface is detected by capturing it with a camera or by measuring the surface roughness. Further, the grinding / measuring tool 30 is capable of rotating each tool by a high-frequency motor 37 at a predetermined number of rotations, and controlling the air cylinder 39 supporting the high-frequency motor 37 to adjust the pressing pressure of each tool against the work 9. is there. With such a special grinding / measuring tool 30, the processing amount for the work 9 can be finely adjusted. Furthermore, the AAC 15 according to the present embodiment is not limited to the special attachment 17 described above, and also has an attachment without a pressing pressure adjusting mechanism that a normal 5-axis machine has.

FIG. 4 is an explanatory diagram showing in block diagram what kind of information is exchanged between the controllers 27, 29 and various devices described in detail above.

As is clear from the figure, the free-form surface processing machine of this embodiment is CAD
Configured to form part of the system, the two controllers 27,29 are subordinate to CAD. Reference numeral 40 is a central monitoring system that links information compatibility between the CAD and this free-form surface processing machine. Directly below that is a grinding condition system that calculates grinding conditions according to commands from the central monitoring system 40.
42, processing machine drive data calculation system 44 and shape measuring machine 21
A measuring machine drive system 46 that controls the operation of

First, from the side of the processing machine, the grinding condition calculation system 42 for inputting information on how much grinding should be executed from the central monitoring system 40 is a condition for grinding from various grinding correlations input in advance, for example, The pressing force F, the tool moving speed V, the contact angle θ with the work, and the like are determined. The correlation between the operation of the tool, which is the basis of the condition calculation, and the grinding amount for the operation is determined theoretically or experimentally and is input as the above-mentioned grinding correlation. The calculation result of this grinding condition calculation system 42,
When the output from the central monitoring system 40 is simply surface polishing that does not require calculation of grinding conditions, the output is directly input to the machine tool drive data calculation system 44.
Here, how to drive the processing machine and how to respond to the command from each of the above-mentioned high-level machines is calculated, and the result is input to the controller 27 described above. On the side of the shape measuring machine, the measuring machine drive data calculation system 46 commands the controller 29 to start up in response to a signal from the central monitoring system 40, and detects the shape of the given work in three dimensions.

On the other hand, there is information transmitted to the central monitoring system 40 side. When the attachment having the above-described shape sensor 33 is used, the detection output from the sensor 33 is input to the grinding state determination system 48 and the polishing state determination 50. The grinding condition determination system 48 gives data indicating the grinding condition to the grinding condition calculation system 42, and a feed hack system for grinding is configured therein. The polishing state determination system 50 is also for transmitting the polishing state to the host central monitoring system 40, and its output is given to the re-polishing command system 52. This re-polishing command system 52 determines whether or not the polishing state of the work 9 is sufficient, that is, whether or not re-polishing is required. The central monitoring system 40 informs the determination result and the portion of the work 9 that needs re-polishing. Give information.

Further, the controller 29 of the shape measuring machine 21 gives the output from the shape measuring machine, that is, the shape information to the measurement data judging system 54. This measurement data determination measurement system 54 simultaneously inputs the CAD data, that is, the data of the final shape of the workpiece 9 through the central monitoring system 40 at the same time, compares these two data, and regrinds the result. Notify the command system 56. And this re-grinding command system 56
Judges whether or not re-grinding is necessary based on the comparison result of the above data, and transmits the judgment to the data central monitoring system 40 of the part of the work 9 on which the judgment is made.

Next, the operation of the free-form surface processing machine of this embodiment having the above configuration will be described.

For example, in order to manufacture a die, the free-form surface processing machine of this embodiment proceeds to the basic routine shown in FIG.

First, information about the shape of the mold to be manufactured is input from the database created by the upper CAD (step 100). Then, based on the obtained information, a carving process (step 200), which is a so-called cutting process for approximating the workpiece to the above-mentioned shape information, is executed, and the shape after the carving is subjected to higher surface accuracy. Rough finishing (formation 1) (Step 30
0), shape formation (shape formation 2) (step 400), and polishing (step 500) are sequentially executed. As a result, what is drawn on the drawing by CAD can be obtained as a product having an actual three-dimensional shape.

Incidentally, the characteristic control of the present invention is, as will be described in detail later, the processing of rough finishing of step 300 and the shaping of step 400, and both processings are only slightly different in the degree of cutting,
Both processes correspond to the shaping process (described in the claims).

FIG. 6 is an explanatory diagram for explaining the function of each of the above steps. As shown in the figure, the work 9 is roughly cut into a strip shape by a die-cutting tool and is roughly modeled. After that, rough cutting, which is extremely rough polishing, was performed to eliminate the large number of cutter marks caused by the engraving (about 0.08
mm deep grinding), and then so-called shape forming (depth grinding of about 0.15 mm) is performed to finish the shape according to the information from CAD. The last polishing (polishing to a depth of about 0.01 mm) is not accompanied by a change in the shape of the work 9, but is polishing performed by an extremely fine grindstone in order to further improve the surface accuracy.

Hereinafter, the work order will be described.

The above-mentioned engraving (step 200) is performed by a ball end mill or the like which is usually used. This is the X axis, the Y axis,
This is because the machined surface does not need any precision as long as it has a three-dimensional Z-axis degree of freedom. Therefore, a simple three-dimensional automatic grinding machine has been proposed. Although the operation is not described in detail here, the free-form surface processing machine of this embodiment is characterized by the subsequent processing (step 300 and step 400).

Next, the work 9 having the rough shape formed by die-cutting is automatically rough-finished (step 300).

FIG. 3 shows the operating state of the grinding / measurement tool 30 of the free-form surface processing machine which is performing rough finishing.
As described above, the grinding / measuring tool 30 to which the roughing grindstone 31 is attached can be moved to an arbitrary position with respect to the work 9 by the 5-axis control by the X-axis, Y-axis, Z-axis, A-axis and C-axis. . The grinding / measuring tool 30 has a variable pressing pressure against the work 9 by the operation of the air cylinder 39 incorporated therein. Such a grinding and measurement tool 30
Is controlled as follows, and rough work is performed.

FIG. 7 is a flow chart of control for grinding for the rough finish (formation first). In this process, as learning control, the cutting condition (processing condition) is changed based on the measurement of the relative shape of the work 9, and the re-cutting (reprocessing) is controlled based on the measurement of the absolute shape.

As shown in the figure, step 310 drives the grinding / measuring tool 30 in accordance with the CAD information to grind a three-dimensional curved surface, and by this processing, temporary grinding is performed. During this cutting, the relative shape of the work 9 is measured by the shape sensor 33 in step 311. That is, the state of cutting is measured by a camera or the like. In the following step 312, the grinding status is detected from the shape information of the relative shape measured in the step 311, and the grinding condition calculation system 42 calculates and compares how much difference there is with the currently executed grinding. . Then, based on the comparison result obtained in this way, the extent to which the mathematical formulas, constants, etc., which are the basis of the grinding used in the calculation in the grinding condition calculation system 42, should be changed, and the cutting conditions are changed.

Here, the learning control, which is the processing for changing the cutting conditions, will be described in detail with reference to the block diagram shown in FIG.

As shown, this learning control learns the grinding conditions based on the detection result of the shape sensor 33. First, the shape information of the work 9 detected by the shape sensor 33 is input to the grinding state determination system 48. The grinding condition determination system 48 detects the grinding condition from the information, compares the grinding condition with the grinding condition calculation system 42, and compares the grinding condition with the currently executed grinding. Then, based on the comparison results obtained in this way, a grinding condition calculation system
The amount of so-called learning correction, that is, how much the basic mathematical formulas and constants used for the calculation in 42 should be changed, is calculated, and the result is input to the grinding condition calculation system 42 and reflected in the subsequent condition calculation. It is. With this learning control, the control amount for the six axes of the processing machine can always be maintained in the optimum state, and highly accurate processing can be realized.

Then, while performing the learning control, step 313
If it is determined that the cutting is temporarily completed in step 314, the process proceeds to the next step 314, while if it is determined that the cutting is not completed, the process returns to step 310 to perform the cutting again.

In step 314, the work 9 is moved to the shape measuring machine 21 by the operation of the APC, and the absolute shape of the work 9 is measured by the shape measuring machine 21.

In the following step 315, the measured three-dimensional information of the absolute shape is compared with the information from CAD to calculate the grinding shortage amount (processing shortage amount). In the following step 316, it is judged whether or not the grinding shortage amount calculated in step 315 is equal to or more than a set value set to achieve a predetermined accuracy, and it is recognized that re-grinding is necessary (with the set value or more). As far as possible, the process returns to step 310 again and the above processing is repeated.

That is, if the process using the information on the relative shape of the work 9 and the process using the information on the absolute shape in steps 310 to 316 are explained based on the block diagram shown in FIG. 4, they are as follows. Become.

First, the grinding condition calculation system 42, which inputs data on how much grinding should be performed from the central monitoring system 40 based on CAD information, calculates the grinding conditions for performing the grinding faithful to the data, and processes the result. It is sent to the machine drive data calculation system 44. In accordance with this, the processing machine drive data calculation system 44 instructs the controller 27 on the control amount and the processing machine 1
Works. In this way, after the temporary grinding is performed in accordance with the CAD information, the work 9 is measured by the APC on the shape measuring machine 21.
Is moved to and used for shape measurement. Then, this measurement result is compared with the CAD information by the operation of the controller 29, the measurement data determination system 54, and the re-grinding command system 56, and the place where the grinding is still insufficient and the degree of the lack are sent to the central monitoring system 40. It will be sent. After that, the central monitoring system 40 operates as described above.

The process of step 400 shown in FIG. 5, that is, the process of forming the shape (shape forming 2), is almost the same as the above-mentioned step 300, and the similar control unit operates according to the flowchart similar to FIG. And grind. However, what is different from rough finishing here is the accuracy of the surface, and in the step 400 shape formation, a finer grindstone is used as a tool, and more accurate shape measurement is used as much as possible for CAD information. Realize a close shape.

Here, FIG. 8 shows a calculation method of the grinding condition calculation system 42 performed in the above steps 300 and 400.

When the central monitoring system 40 inputs how much an arbitrary point on the surface of the work 9 as shown in (A) and the point of coordinates (x, y, z) is to be ground, as shown in (B). Then, the normal vector (i, j, k) of the point to be ground is calculated.
This can be obtained by normal graphic processing because the shape of the point of coordinates (x, y, z) is three-dimensionally grasped from the information from the shape measuring machine 21. Then, the control amounts of all the six axes of the processing machine described above are determined from the values of (x, y, z) and (i, j, k). That is, first of all, among the 6 axes, X,
The control amounts of the Y and Z axes are uniquely determined by moving the tool to the position of the point (x, y, z) on the work 9,
The contact area between the work 9 and the tool is determined by the control amounts of the axis and the C axis. Next, the control amount of the pressing pressure (Fa) on the work 9 necessary for performing the desired grinding is determined.

After finishing the grinding, rough finishing, and shape forming based on the above control, polishing (step 500 in FIG. 5) is executed.

This polishing is not intended to give the work 9 a shape change, but is simply a treatment for improving the surface accuracy. Therefore, the measurement of the three-dimensional shape using the shape measuring machine 21 as described above is not performed, and the control is performed according to the flowchart whose details are shown in FIG. That is, polishing of the three-dimensional curved surface is performed (step 50
1) detect the surface roughness of the execution part (step 502),
The process returns to step 501 again and the same control is repeated until the surface roughness becomes a desired value or less (step 503).

As is clear from the control of each step described above, it is not necessary to grasp the absolute three-dimensional shape of the work 9 in the control at this time, and it is only necessary to grasp the surface roughness within a narrow range for the portion where polishing is performed. Degree measurement is sufficient. Further, since the polishing is also a work of polishing the surface of the work 9 uniformly, control of the processing amount such as pressing pressure is not required as much as finishing.
Therefore, during this work, the air cylinder 39 is provided as a tool, and constant pressure copying control can be adopted.

What executes this control is a polishing state determination system 50 that inputs the output of the shape sensor 33 shown in the block diagram of FIG.
A re-polishing command system 52 for determining whether re-polishing is required from the output, and a central monitoring system 40 for operating the processing machine drive data calculation system 44 based on the command.

According to the free-form surface processing machine configured and controlled as described above, it is possible to realize an arbitrary three-dimensional shape without human intervention. Moreover, since the process from die engraving to polishing is fully automated, no human intervention is required in the process. Further, since the control is accurately executed based on the digitized information called CAD data, human error and unevenness are eliminated, the precision of the three-dimensional curved surface is extremely high, and troublesome work such as teaching is unnecessary. Further, by adopting the simple shape sensor 33 that detects the relative shape of the workpiece 9, learning control can be executed at the same time during grinding and high-precision machining can be maintained. In addition, constant time scanning control can also be executed because the time required for processing is short-circuited during polishing.

[Effects of the Invention] As described in detail with reference to the embodiments above, the free-form surface processing machine of the present invention has a machining means, a workpiece relative shape measuring means, a machining condition changing means, a workpiece absolute shape measuring means, and a machining shortage amount calculation. Means and reprocessing control means are provided.

Therefore, all the machining according to the finished shape is automatically completed. Moreover, since even the amount of machining can be controlled, the precision of the machined surface is high, and even the process that ultimately relied on a skilled worker such as polishing can be replaced by this free-form surface processing machine. It will be.

Particularly in the present invention, the relative shape of the workpiece is measured during processing,
By comparing this information with the target shape and changing the machining conditions, it is possible to compensate for, for example, clogging and wear of the machining tool and perform machining under optimum machining conditions. With it. The absolute shape of the workpiece is measured, this information is compared with the target shape to determine the machining shortage amount, and when this machining shortage amount is large, re-machining is performed, so it is possible to perform precise shape forming processing. Produce an effect.

[Brief description of drawings]

1 is a basic configuration diagram of the present invention, FIG. 2 is a schematic diagram of the configuration of an embodiment, FIG. 3 is an explanatory diagram of its attachment, FIG. 4 is a block diagram of its control system, and FIG. 5 is its control. A flow chart of the basic routine, FIG. 6 is an explanatory view of the work, FIG. 7 is a detailed flow chart of the grinding work, FIG. 8 is an explanatory view of the control amount calculation method, and FIG. 9 is a learning control during grinding. Explanatory drawing and FIG. 10 show a detailed flowchart of the polishing operation. C1 …… Machining means C2 …… Work relative shape measuring means C3 …… Machining condition changing means C4 …… Absolute shape measuring means C5 …… Machining shortage amount calculating means C6 …… Re-machining control means 1 …… Machining machine 9… … Work 15 …… AAC 17 …… Attachment 19 …… ATC 27,29 …… Controller

Continuation of the front page (72) Inventor Katsuiku 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Co., Ltd. (72) Inventor, Hideto Watanabe 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Co., Ltd. ( 72) Inventor Masaaki Utsumi 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (56) References JP-A-58-45863 (JP, A) JP-A-55-144981 (JP, A) JP-B 54-24156 (JP, B2)

Claims (1)

[Claims] 1. A free-form surface processing machine for determining a finished three-dimensional curved surface shape, which is a target shape of a work, on the basis of data, storing the shape, and performing shape formation by grinding after cutting the work. In order to realize the target shape of the work, the working tool is moved to an arbitrary position on the work under a predetermined working condition, and a working means for changing a working amount of the work tool to the work, and grinding by the working means. The workpiece relative shape measuring means for measuring the relative shape of the workpiece in the processing range, and the relative shape of the workpiece measured by the workpiece relative shape measuring means and the target shape of the workpiece are compared, Machining condition changing means for changing the machining conditions of the means, workpiece absolute shape measuring means for measuring the absolute shape of the workpiece machined by the machining means, and the workpiece Machining shortage amount calculating means for calculating the machining shortage amount by comparing the absolute shape of the work measured by the pair shape measuring means and the target shape of the work, and the machining shortage amount calculated by the machining shortage amount calculating means. A free-form surface processing machine comprising: a re-machining control means for performing re-machining when is greater than or equal to a predetermined value.