JPH0242607B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a machining method for replacing green jaws in continuous machining of a variety of workpieces.

As is well known, after the raw jaw is attached to the chuck at the end of the spindle,
Since it is used after cutting with a boring tool according to the diameter of the workpiece, it is possible to accurately center the workpiece without being affected by installation errors of the green jaws. In addition, since the free jaw is machined to match the diameter of the workpiece, the workpiece can be stably gripped during machining.

With the recent automation of machine tools and production lines based on unmanned and systemized systems, processing of workpieces, such as front and back machining of workpieces, and a series of machining from rough machining to finishing machining, is changing depending on the type of workpiece. In order to continuously and automatically perform the process, there is a demand for automatic replacement of the green nail and automatic replacement of the green nail jig, ie, the mandrel used in green nail processing.

However, although devices for replacing green jaws and devices for attaching and removing mandrels have conventionally been provided, whenever the type of workpiece, that is, the shape and diameter of the workpiece changes, it is necessary to manually select the green jaws and mandrel that are suitable for the workpiece. As a result, it became a bottleneck in completely automating machine tools and production lines. In addition, if there are many types of workpieces, the frequency of replacing and machining the green jaws will increase, so although it is economically important to reduce the total amount of machining of the green jaws, conventional manual methods can reduce the amount of machining of the green jaws. It was not possible to reduce the amount.

The present invention has been made in view of the above circumstances, and the purpose of the present invention is to reduce the amount of machining of raw nails in order to minimize the cutting allowance even when machining raw nails without machining raw nails in principle. However, it is an object of the present invention to provide a method for automatically performing the process of replacing the raw nails by determining the optimum replacement, shift, and mandrel diameter of the raw nails.

In order to achieve this object, the present invention is equipped with a large number of free jaws and a large number of mandrels for processing the loose jaws, and replaces the loose jaws of the chuck every time the type of workpiece changes, when continuously machining various types of workpieces. A processing method of an NC machine tool in which the core metal is grasped by the raw jaws and the raw jaws are machined to a predetermined diameter, and the method includes various data including the diameters of the plurality of raw jaws, diameter data of the plurality of core metals grasped by the raw jaws, and Various data including the diameters of multiple workpieces grasped by the raw jaws are
a step of storing data in the NC machine tool; a step of comparing various data of the plurality of stored raw jaws in order to select the raw jaw that best matches the grasping conditions when gripping a given workpiece with a chuck; a step of calculating the diameter of the mandrel to be determined for the green jaw that is determined to be most applicable to the predetermined workpiece based on the results of the comparison; a step of selecting the mandrel diameter data that best matches the calculation result from the stored mandrel diameter data; If the workpiece cannot be grasped during the step of transporting the raw jaw from the raw jaw storage to the chuck and the grasping process of the raw jaw attached to a predetermined position of the chuck, the workpiece is moved to a predetermined position in the radial direction of the chuck that can grasp the workpiece. a step of setting a raw nail by shifting it, and transporting the selected mandrel that matches the set raw jaw from a mandrel storage and attaching it to the raw jaw; and conditions that allow the raw jaw with the mandrel attached to grasp a predetermined workpiece. The present invention is a method for replacing the raw jaws in continuous machining of a variety of workpieces, characterized in that the method comprises steps for machining according to the process. To express the configuration of the present invention more specifically, when a machine tool continuously processes various types of workpieces, a large number of free jaws and a large number of mandrels for processing free jaws are provided, and each time the type of workpiece to be machined changes. A method for replacing and processing a green jaw, a step of storing data on the diameter and shape of the workpiece, data on the diameter and shape of the green jaw, data on the mandrel grasping part diameter, and data on the diameter of the mandrel in a storage device;
The data of the smallest workpiece among unprocessed workpieces is determined to determine the shape of the green jaw required for machining, and the shape data is compared with the data of the shape of the green jaw installed on the machine tool to determine the need for replacing the green jaw. a procedure for determining whether
A procedure for determining the existence of similar jaws by comparing data on the shape and diameter of the raw jaws required for machining the workpiece with data on the shape and diameter of the raw jaws stored in the storage device when replacement of the raw jaws is required. and, when the raw jaws or standard jaws installed on the machine tool are shifted and closed to the smallest size within the safe stroke range, when the raw jaws do not need to be replaced, or when the raw jaws need to be replaced and similar jaws do not exist, the raw jaws are closed to the smallest size within the safe stroke range. The procedure of comparing the diameter of the workpiece with the value obtained by subtracting the standard machining amount for raw jaw machining from the diameter of the workpiece to determine whether or not a raw jaw shift is possible, and when the raw jaw shift is not possible for a standard jaw, the data of the standard jaw is The procedure of reading and calculating the required core diameter, the procedure of reading the raw jaw data and calculating the required number of pitches and required core diameter of raw jaw shift when raw jaw shift is possible, and the procedure of reading raw jaw data and calculating the required number of pitches and required core diameter of raw jaws installed on the machine tool. When the raw jaw shift is not possible, compare the value obtained by subtracting the diameter of the workpiece from the diameter of the raw jaw when the raw jaw is opened to the maximum within the safe stroke range and the required safety margin when mounting the workpiece. A procedure for determining whether processing of a raw nail is necessary, a procedure for calculating the necessary core diameter when processing of a raw nail is necessary, a first state in which a similar nail exists that requires replacement of a raw nail, and a similar nail that requires replacement of a raw nail. A second state in which a natural nail shift is not possible because no similar nail exists, and a third state in which a natural nail replacement is required and a similar nail does not exist and a natural nail shift is possible.
A procedure for issuing a raw nail replacement command in the state, a fourth state in which a raw nail shift is possible without requiring raw nail replacement, a procedure for issuing a raw nail shift command in the third state where raw nail replacement is completed, and a procedure for issuing a raw nail shift command in the third state where raw nail replacement is completed, and a procedure for issuing a raw nail shift command in the third state where raw nail replacement is completed. In the fifth state where the raw nail shift is not possible and raw nail machining is required, in the first and second states where the raw nail replacement is completed, and in the third and fourth states where the raw nail shift is completed, the mandrel installation command, the raw nail machining command, and the mandrel. A procedure for issuing a removal command, a sixth state in which a raw jaw shift is not required and no raw jaw machining is required, and a state in which the core metal removal is completed and the smallest of the unprocessed workpieces is set. The present invention is a method for changing the raw jaws in continuous machining of various types of workpieces, which is characterized by the steps of mounting the workpiece on a machine tool and issuing a machining command.

Embodiments of the present invention will be described below based on the drawings. FIG. 1 is a block diagram of a raw nail replacement processing system that implements the raw nail replacement processing method according to the present invention. In FIG. 1, the machine tool 1 may be a numerically controlled machine tool such as a machining center, which may be used alone, or a plurality of machine tools connected in parallel or series in a production line may be used. In the embodiment described below, in order to share the diameter range of the workpiece to be machined, three parallel machine tools are used, each of which targets a different range of machining diameters. As shown in FIG. 1, this embodiment further includes a raw nail changing device 2 that also serves as a raw nail shifting device, a mandrel attaching/detaching device 3, a storage device including a main storage device, a machine tool 1, and each of the above-mentioned devices 2. A central processing unit 5 consisting of a control unit and an arithmetic unit connected to 4 is provided.

FIG. 2 is a front view and a sectional view thereof illustrating the natural nail changing device 2. FIG. A raw nail storage 7 for storing a large number of raw nails 6 is provided outside the machine tool 1,
A guide 8 is installed between the vicinity of the raw nail storage 7 and the main body of the machine tool 1. A carrier 10 is movable along the guide 8 by driving a servo motor 9, and an arm 12 is movable relative to the carrier 10 in the radial direction of the chuck 13 of the machine tool 1 by driving a servo motor 11. A hand 14 is attached to the tip of the arm 12, and the hand 14 can be opened and closed by the drive of a servo motor 15 to grasp the raw nail 6. Reference numeral 16 denotes a drive device which can be rotated by a servo motor and moved freely in the radial direction of the chuck 13 in order to operate a locking member that locks the unformed jaw 6 to the chuck 13 side pawl holder and release the unformed jaw 6. be. In the raw nail storage 7, depending on the shape H and diameter D of the workpiece to be machined, the shape h of the raw jaw, that is, the height of the chuck portion 6c h ₁ , h ₂ , h ₃ , as illustrated in FIG. 3, is stored. Various kinds of raw nails 6 having different diameters c are stored for each different type. To replace a raw nail using the raw nail replacement device 2, the raw nail 6 attached to the chuck 13 is grasped by the handle 14, the lock of the raw jaw 6 is released by the drive device 16, and the servo motor 11 is activated. Raw nail 6 by driving
is removed from the chuck 13, and the raw nail 6 is stored in the raw nail storage 7 by moving the carrier 10. Next, the necessary raw nails 6 are extracted from the large number of raw nails 6 in the raw nail storage 7.
Select the carrier 1, hold it with the hand 14, and
0 and the arm 12, the raw nail 6 is inserted into the chuck 13 to a predetermined position, the raw nail 6 is locked, and the raw nail replacement is completed. In addition, in order to shift the unformed jaw 6 installed in the chuck 13 using the unformed nail changing device 2, the unlatched jaw 6 is released by the drive device 16 while the unformed jaw 6 is gripped by the hand 14, and the servo By driving the motor 11, the free jaw 6 is moved in the radial direction of the chuck 13 by a distance corresponding to a predetermined integral multiple of the rack pitch P, and the loose jaw 6 is locked. The raw nail replacement device 2 described above is shown as an example of the device used when carrying out the raw nail replacement processing method of the present invention, and the features of the present invention appear in the structure of the raw nail replacement device 2 itself. It's not something that exists. Therefore, as long as the raw nail changing device 2 is equipped with a large number of raw nails and can perform raw nail replacement and raw nail shifting, it is not limited to the structure described above, but other structures can be used.

FIG. 4 is a plan view and a front view of the mandrel attaching/detaching device 3 in the direction of the arrows. A mandrel storage 18 for storing a large number of mandrels 17 is provided outside the machine tool 1, and the mandrel storage 18 and the chuck 1 of the machine tool 1 are connected to each other.
A base 19 is installed at an intermediate position between 3 and 3.
A column 20 is mounted on the base 19 so as to be movable in the Z direction, and an arm 21 is movable up and down in the Y direction, pivotable in the B direction, and movable in the X direction relative to the column 20. A hand 2 is attached to the tip of the arm 21.
2 is attached so as to be rotatable in the A direction. The mandrel storage 18 stores a large number of mandrels 17 having a diameter d of a predetermined pitch. The dimensions of the predetermined pitch are determined in consideration of the reduction in the amount of raw nail machining, which will be described later. In order to attach and detach the mandrel 17 using the mandrel attaching/detaching device 3, the arm 21 is moved up and down in the Y direction and rotated in the B direction to position the arm 21 toward the mandrel 17 of the required diameter in the mandrel storage 18. Seshime, arm 21
is moved in the X direction, and then the mandrel 1 is moved with the hand 22.
7, and then move the mandrel 17 to the chuck 13 by combining the movement of the arm 21 in the X direction, the rotation of the hand 22 in the A direction, the vertical movement of the arm 21 in the Y direction, the rotation in the B direction, and the movement of the column 20 in the Z direction. Attach between 6 natural nails. In order to return the mandrel 17 attached between the free jaws 6 of the chuck 13 to the mandrel storage 18, the operation for attaching the mandrel to the chuck 13 described above may be performed almost in reverse. The mandrel attaching/detaching device 3 described above is shown as an example of the device used when carrying out the raw nail replacement processing method of the present invention, and the structure of the mandrel attaching/detaching device 3 itself has the characteristics of the present invention. It is not what is appearing. Therefore, the mandrel attaching/detaching device 3 is not limited to the structure described above, but may have any other structure as long as it is equipped with a large number of mandrels and can attach and detach the mandrel 17 between the free jaws 6 of the chuck 13. can be used.

FIG. 5 is an explanatory diagram showing the dimensional relationship in green nail shifting and green nail processing. FIG. 5A shows a state in which the free jaw 6 is attached to the reference position of the chuck and the chuck is opened to the maximum within the range of the safe stroke _Ss , which is defined as a range narrower than the opening margin of the chuck. In this state, the diameter of the green jaw 6, that is, the diameter of the gripping part 6c, is c, and the reference diameter, that is, the diameter of the mandrel chuck 6e is e.
shall be. FIG. 5B shows a state in which the free jaw 6 is shifted and the chuck is opened to the maximum within the range of the safe stroke _Ss , similar to FIG. 5A. In this state, the diameter of the raw nail 6 is assumed to be g, and the reference diameter is assumed to be f. If the shift pitch number is x, the shift amount is about the radius
It becomes xp. Therefore, f=e+2xp and g=c+2xp hold true. FIG. 5C shows a state in which the mandrel 17 having a diameter d is gripped by the free jaws 6. In this state, the diameter of the raw nail 6 is defined as b. FIG. 5D shows a state in which the gripping portion 6c in FIG. 5C has been machined to have a diameter equal to the diameter D of the workpiece. The standard cutting allowance Am is defined as the minimum cutting allowance within the range in which the grip portion 6c before machining does not remain. FIG. 5E shows the state in which the chuck in FIG. 5C is opened to the maximum within the range of the safe stroke _Ss after machining the raw nail. In this state, the diameter of the raw nail 6 is defined as a.
The distance between the raw jaw and the mandrel or workpiece, which is determined by taking into account the misalignment of the mandrel gripped by the mandrel attachment/detaching device or the workpiece held by a work feeder (not shown) with respect to the chuck when the mandrel or workpiece is attached. Let the safety margin of A _s be. Therefore, A _s ≦a−D=f−
It is required that d≦2S _s . . Above, we have explained the case of machining a raw nail that has been shifted from the reference position in Fig. 5 A to E. However, regarding the raw jaw that has already been shifted and has been machined and is attached to the chuck, we will perform the next machining target. The fifth method is also used when performing raw nail shifting and raw nail processing to suit the object.
The same relationships as in Figures A to H hold true. In this case, safely stroke the chuck with this natural nail attached.
The diameter c and the reference diameter e of the chuck in the maximum open state within the range of S _s are equal to the diameter a and the reference diameter f in the open state after the previous chuck processing.

FIGS. 6 and 7 are flowcharts showing various steps of a raw nail replacement processing method according to an embodiment of the present invention. According to the processing schedule, one lot of workpieces, for example, one day's worth of workpieces, is prepared in the work stocker, and a large number of raw nails and core metals are stored in the raw nail storage and core metal storage, respectively, as shown in Fig. 6. Start a flow. First, the diameter D and shape H of the workpiece are stored in the storage device as workpiece data, the diameter c and shape h of the raw jaw as raw jaw data, and the reference diameter e of the mandrel chuck part.
Then, the pawl diameter a during chuck unclamping after pawl machining and the mandrel diameter d are stored as mandrel data (step 31). When a plurality of machine tools are used in parallel, the workpieces are divided into groups to be machined by one of the machine tools according to the machining range determined by the chuck diameter of each machine tool (step 32). The workpieces assigned to each machine tool are numbered in descending order of their diameter D. Usually, a plurality of workpieces having the same diameter and the same shape are machined, so it is possible to assign the same number to these workpieces of the same type. The reason why workpieces are numbered in order of decreasing diameter is to machine the workpieces in order of decreasing diameter. Therefore, if the workpieces prepared on the work feeder are already lined up in descending order of diameter, they can be machined in that order. In addition, if the workpieces are arranged randomly on the work feeder, use a device that can take out the workpieces in order of small diameter as instructed by the central processing unit as a device for transporting the workpieces from the work feeder to the machine tool (step 33). ).

The following steps are common to all machine tools, so we will explain them for one machine tool. First, the workpiece data regarding the workpiece to be machined, that is, the one with the smallest diameter among the unprocessed workpieces for the machine tool, is read out (step 34), and the green jaw replacement and green jaw machining are performed as explained later with reference to the flowchart of FIG. (Step 35). After that, the workpiece is mounted, machining measurement and machining judgment are carried out according to the normal method (steps 36 to 39), and if machining is not possible and re-machining is possible, after re-machining (step 40),
The workpieces are carried out (step 41), and the above procedure is repeated until all workpieces are completed (step 42).

The flow of green nail replacement and green nail processing will be explained with reference to FIG. First, depending on the thickness of the workpiece to be machined next, h is determined as the shape of the free jaws that grip the workpiece (step 51). The shape of the natural nail currently attached to the chuck is read out from the storage device as _h0 (step 52), and by comparing h and _h0 , it is determined whether or not the natural nail needs to be replaced (step 53). If it is necessary to replace the raw nails, it is determined whether similar nails are stored while reading the raw nail data of the raw nails stored in the raw nail storage from the storage device (step 54). A similar jaw is selected that can be used for machining a workpiece by machining the raw jaw by a standard cutting allowance A _s without performing a raw jaw shift and using a mandrel with the same core diameter as before. Therefore, when determining similar nails, let the similar data be D ₁ , f ₁ , d _{1 ,} and if there is a raw nail that satisfies D ₁ = D - Am f ₁ - _{d 1} ≦2S _s - A _s , then there is a similar nail. shall be. If there is a similar nail, this is set as the first state.

If it is determined in step 54 that there is no similar jaw, the standard jaw will be used, and when the standard jaw is shifted by one pitch, the standard cutting allowance Am will be applied to the workpiece diameter D within the safe stroke range.
It is determined whether or not the raw nail diameter can be obtained taking into account the following equation, 2P+c-2S _s +Am>D, and whether or not the shift is possible is determined (step 55). If the shift is not possible, set this as the second state,
Core diameter d that allows for green jaw machining with standard cutting allowance Am
(Step 56). Next, it is determined whether or not the mandrel having the mandrel diameter d can be gripped with a sufficient safety margin A _s (step 57), and if it can be gripped, the step
The mandrel diameter d calculated in step 56 is used, and if gripping is not possible, a smaller mandrel diameter calculated in step 58 is used to obtain a machining allowance larger than the standard machining allowance Am. If the calculated value of d takes a fraction that is not included in the mandrel diameter prepared in the mandrel storage, the mandrel diameter of the value that is rounded down will be used, and in this case, only the amount equivalent to that fraction will be used. It is necessary to take a large cutting allowance. The same applies when a fraction occurs in the mandrel diameter d in each subsequent step.

If the shift is possible in step 55, this is set as the third state.

If it is determined in step 53 that nail replacement is not necessary, the currently installed natural nail is used, and it is determined whether or not the natural nail can be shifted using a formula almost the same as in step 55 (step 59). .
A fourth state is a case where shift is possible.

If the shift is not possible in step 59, it is determined whether the workpiece can be gripped with a sufficient safety margin A _s without machining the workpiece (step 60), and if gripping is not possible, this is In step 61, the core diameter d is calculated in order to perform machining with the minimum machining allowance sufficient to provide a sufficient safety margin _As .

If the grip is possible in step 60, this is set as the sixth state.

In the third and fourth states, a group of steps for determining the number of shift pitches x and the mandrel diameter d to be used for machining the raw nail after shifting the raw nail is comprehensively indicated by 62. Step group 62 is an example of a step group in which x and d are determined for the purpose of reducing the amount of raw nail machining as much as possible. Therefore, before sequentially explaining each step in the step group 62, its principle will be explained based on FIGS. 8 and 9. In FIG. 8, since the diameter of the gripping portion 6c of the free jaw 6 in the maximum open state is φ _c , the range in which the gripping portion 6c can be positioned without shifting is the range indicated by the S _s arrow. If the standard cutting allowance Am is taken as the cutting allowance, the range in which the gripping portion 6c after machining the raw nails can be positioned is the range indicated by the T arrow. Therefore, since a safety margin A _s is taken for gripping the workpiece, the range of the diameter of the workpiece that can be gripped by the gripping portion 6c after machining the soft jaws is the range indicated by the arrow Q. It is not possible to grip a workpiece with a diameter below the range of Q.
In addition, in order to grip a workpiece with a diameter exceeding the range of Q, the cutting allowance must exceed the standard cutting allowance Am.

What has been described above regarding the case where the diameter of the raw nail is c applies similarly to the case where the raw nail is shifted. If the diameter of the workpiece W is included in the range of Q when the raw jaw is not shifted or when the raw jaw is shifted, the shift state corresponding to this range of Q is taken and the minimum cutting allowance, that is, the standard cutting allowance is set. Raw nail processing can be performed. For example, in FIG. 8, when the diameter of the workpiece W is D, the diameter D is included in the range of Q when shifted by 2 pitches, so it is sufficient to shift the workpiece by 2 pitches and perform the soft-jaw machining. In addition, in the same figure, when the diameter of the workpiece W is D ₀ , the diameter D ₀ is included in the range of Q when shifted by 1 pitch and the range of Q when shifted by 2 pitches. It is possible to perform machining, and it is also possible to perform raw nail machining by shifting 2 pitches. When the diameter of the workpiece W is D in FIG. 9, it is sufficient to perform the soft-jaw machining by shifting two pitches in the same manner as described above for the case where the diameter of the workpiece W is D in FIG. If the diameter of the workpiece W is not included in any of the ranges of Q, it is not possible to take the standard cutting allowance, and it is necessary to take a shift state that corresponds to the range of R that minimizes the cutting allowance. . For example, when the diameter of the workpiece is D ₀ in Fig. 9, the diameter D ₀ is not included in any of the ranges of Q, so the state that has been shifted the most within the range of R that includes the diameter D ₀ 1
All you have to do is pitch shift and process the raw nails.

The formula for minimizing the amount of raw nail machining is shown above.
The lower limit x ₁ and upper limit x ₂ of the number of shift pitches x required to perform green jaw machining corresponding to a workpiece of diameter D using the standard cutting allowance are x ₁ = (D - Am) - c + 2S _s / 2P x ₂ =D+A _s -Am-c/2P. Therefore, if there is one integer x such that x ₁ ≦x≦x ₂ , it is shifted by x pitch, and if there are two or more integers x that satisfy this condition, either x
Integer x that satisfies this condition by shifting by pitch
If does not exist, x ₁ or the integer x truncated from x ₁
Shift only the pitch.

The above discussion has focused on minimizing the machining allowance, but the actual steps to be taken will be explained with reference to Fig. 7 62. First, the state in which the mandrel is gripped after shifting should be located at the center of the safe stroke S _s range. Assuming that C=g-2xp =b+ _Ss -2xp=D-Am+ _Ss -2xp, x is calculated by x=( _Ss +D-Am)-C/2P (step 63). Since the shift position of the natural nail is regulated by the rack, the large value must be an integer value. x calculated in step 63
When deriving an integer value from x, it is possible to round down or round up x. x in step 64
truncate. The diameter g of the free jaw after the shift is calculated (step 65), g is compared with the workpiece diameter D (step 66), and if g is larger than D, f, b, and d are calculated (step 67). The core metal diameter d calculated here is such that green nail machining can be performed with a standard cutting allowance Am. It is determined whether or not the mandrel of the mandrel diameter D calculated using the calculated reference diameter f can be gripped with a sufficient safety margin A _s (step 68), and if it is possible to grip it, in step 67. The calculated mandrel diameter d is used, and if gripping is not possible, a smaller mandrel diameter calculated in step 69 is used to obtain a machining allowance larger than the standard machining allowance Am.

If g is not larger than D in step 66, x calculated in step 63 is rounded up (step 70) with the aim of minimizing the amount of raw nail machining. g, f,
b and d are calculated (step 71). It is determined whether or not the mandrel having the mandrel diameter d calculated within the range of the safe stroke _Ss can be gripped using the calculated reference diameter f (step 72), and if it is possible to grip it, the value is rounded up as x. For use, proceed to step 68. If gripping is not possible, the cut-off value is used as x (step 73), g is calculated (step
74), join step 67.

Determination of which of the first to sixth states as explained above and calculation of x, d, etc. are performed by the central processing unit 5 in FIG. Next, the sixth
If it is in the state, none of the raw nail replacement, raw nail shift, and raw nail processing is performed, so the flow shown in FIG. 6 is directly ended. If the first to fifth states are present, automatic pawl setting and mandrel automatic setting are performed as follows depending on the state (steps 75 and 76).
In the first to third states, the central processing unit 5 issues a raw nail replacement command to the raw nail replacement device 2, and the raw nail replacement device 2 replaces a similar nail or standard nail specified by the command. When the natural nail replacement end signal is input to the central processing unit 5 in the third state, and in the fourth state,
The central processing unit 5 issues a raw nail shift command to the raw nail replacement device, and the raw nail replacement device 2 performs the raw nail shift by the number of shift pitches x designated by the command. In the first and second states, when the raw nail replacement end signal is input to the central processing unit 5, in the third and fourth states, when the raw nail shift end signal is input to the central processing unit 5, and in the fifth state, The central processing unit 5 issues a mandrel mounting command to the mandrel attachment/detachment device 3 . The mandrel attaching/detaching device 3 attaches a mandrel having a mandrel diameter specified by the command between the raw jaws of the chuck. Next, the central processing unit 5 issues a raw jaw machining command to process the gripping portion 6c of the raw jaw 6 into a size equal to the diameter D of the workpiece (step 77). Measure the measurement and determine whether the machining diameter is acceptable (steps 78 and 79).
If the machining is rejected, it is determined whether further correction is possible (step 80), and if the correction is possible, reprocessing is performed after automatic correction (step 81), and if correction is not possible, the process returns to step 52 and the raw nail is replaced again. Perform processing.
If the processing is successful, the mandrel attachment/detachment device 3, which receives the mandrel removal command from the central processing unit 5, removes the mandrel and returns it to a predetermined position in the mandrel storage 18 (step 82). Next, the data stored in the storage device 4 is updated (step 83), and all steps of the raw nail replacement process are completed.

Thereafter, the machine tool 1 processes the workpiece in response to the workpiece device and the machining command, as described with reference to FIG.

The present invention has the above-described configuration, and allows one or more machine tools to automatically perform green nail replacement and green nail processing using a central processing unit and a storage device. Therefore, it is possible to achieve automation, including unmanned operation at night, especially in the continuous processing of a wide variety of workpieces. In addition, if it is possible to avoid machining the raw jaws, do not process the raw jaws, and when machining the raw jaws, only the standard machining allowance is machined as much as possible. By increasing the machining allowance only when it is not possible to safely grip the jaw, the total machining amount of the raw jaw can be reduced. Therefore, it is possible to reduce the cost of raw nails and tools, and to shorten machining time.

[Brief explanation of drawings]

The drawings represent embodiments of the present invention, with FIG. 1 being a block diagram, FIG. 2 A being a front view of the natural nail changing device, FIG. C is an explanatory diagram of the shape of the green nail, FIG. 4 A is a plan view of the mandrel attaching/detaching device, FIG. 4 B is a front view as seen from the arrow in FIG. 6 is a flowchart showing an outline of workpiece machining including green jaw replacement machining, and 7th
The figure is a flowchart showing the details of the natural nail replacement process.
FIGS. 8 and 9 are explanatory diagrams showing the number of shift pitches and the machining range based on the standard cutting allowance. 1...Machine tool, 2...Hard jaw changing device, 3...
Core metal attaching/detaching device, 4... Memory device, 5... Central processing unit, 6... Raw nail, 17... Core metal.

Claims (1)

[Claims] 1. When continuously machining various types of workpieces, a large number of green jaws and a large number of mandrels for machining the green jaws are provided, and each time the type of workpiece changes, the green jaws of the chuck are replaced and the core metal is replaced. A processing method of an NC machine tool that processes the raw jaws into a predetermined diameter by making the raw jaws grasp various data including the diameters of a plurality of raw jaws, diameter data of a plurality of mandrels grasped by the raw jaws, and the raw jaws grasped by the raw jaws. Various data including the diameter of multiple workpieces to be
a step of storing data in the NC machine tool; a step of comparing various data of the plurality of stored raw jaws in order to select the raw jaw that best matches the grasping conditions when gripping a given workpiece with a chuck; a step of calculating the diameter of the mandrel to be determined for the green jaw that is determined to be most applicable to the predetermined workpiece based on the results of the comparison; a step of selecting the mandrel diameter data that best matches the calculation result from the stored mandrel diameter data; If the workpiece cannot be grasped during the step of transporting the raw jaw from the raw jaw storage to the chuck and the grasping process of the raw jaw attached to a predetermined position of the chuck, the workpiece is moved to a predetermined position in the radial direction of the chuck that can grasp the workpiece. a step of setting a raw nail by shifting it, and transporting the selected mandrel that matches the set raw jaw from a mandrel storage and attaching it to the raw jaw; and conditions that allow the raw jaw with the mandrel attached to grasp a predetermined workpiece. A method for replacing green jaws in continuous machining of a variety of workpieces, consisting of steps for machining according to .