JP3120263B2 - Machining program creation method for facing spindle lathe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an opposed spindle lathe having a pair of opposed spindles and a pair of tool rests capable of machining a workpiece in cooperation with both spindles. It is about how to create.

[0002]

2. Description of the Related Art Conventionally, there has been known an opposed-spindle type NC lathe in which a pair of spindles are arranged opposite to each other on a common machine frame and a pair of tool rests are installed above and below the spindle axis. According to this, the processing efficiency is dramatically improved, for example, the front and back of the work can be processed simultaneously by one lathe.

FIG. 3 shows an example of this type of opposed-spindle lathe, which comprises a left spindle 1, a right spindle 2, a lower tool rest 3, and an upper tool rest 4. Each of the tool rests 3 and 4 can work a workpiece in cooperation with either of the left and right spindles 1 and 2.

[0004] For example, in the case of a work that requires front and back processing, the work is chucked to the left main spindle 1 in a first step, and the surface thereof is processed by a tool attached to the lower tool rest 3. Second
In the process, the work is chucked to the right spindle 2 and the back surface is machined by a tool attached to the upper turret 4. The first step and the second step are performed simultaneously, and the longer processing time of both steps determines the cycle time.

However, the processing time of each step of a general work is often unbalanced. For example, when cutting the workpiece W from the material M shown in FIG. 4, in the first step shown in FIG.
2, and the inner diameter A3 are processed by the lower tool rest. In the second step shown in FIG. 6, the rear end face B1 and the outer diameter B2 of the right main shaft 2 are processed by the upper tool post.

At this time, as shown in FIG. 7A, an imbalance ΔT occurs in the processing time of the upper and lower tool rests,
The processing time of the lower turret, that is, the cycle time becomes considerably long. Therefore, the waiting time of the upper turret that has finished processing earlier becomes longer, and the processing efficiency deteriorates. In such a case, it is usually necessary to rearrange the processes, and a programmer who is familiar with the processing contents has spent a great deal of time and effort.

In view of the above, there has been proposed a technique for automatically canceling the imbalance in machining time between the two spindles. For example, Japanese Patent Application Laid-Open No. 63-169251 discloses that, in an opposed spindle lathe in which dedicated tool rests are installed on the left and right spindles, a part of the machining process of the spindle having the longer machining time is distributed to the other spindle. A method for doing so is disclosed. In Japanese Patent Application Laid-Open No. 4-69131, in addition to a dedicated tool rest for both spindles, a third tool rest movable to both spindles is installed. An opposing main spindle lathe configured to perform assisted machining with the main spindle is disclosed.

[0008]

However, according to the former programming method, for example, a part to be chucked in the second step must be processed in advance in the first step, or rough processing and finishing processing are required. The steps that can be distributed are limited, for example, the steps cannot be performed in reverse order, and each turret can only be machined with its own main spindle. As a result, it was not possible to expect much efficiency UP. Further, according to the latter opposed spindle lathe, it is necessary to install three turrets, which not only increases the machine cost but also complicates the entire machining program.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for creating a simple and efficient machining program in an opposed-spindle lathe having a pair of tool rests, by eliminating imbalance in machining time. .

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a machining program creating method according to the present invention comprises a pair of main spindles facing each other and a pair of main spindles capable of machining a work in cooperation with both main spindles. In an opposed spindle lathe provided with a tool post, a step of calculating the processing time of both tool post based on the processing data, a step of comparing the processing time difference with an allowable value, and a processing time when the processing time difference is larger than the allowable value. A step of searching for a process or a process in which two turrets can be simultaneously machined on the same spindle from the machining data of the longer turret,
It comprises the steps of creating a machining program for both spindles including simultaneous machining or balance machining, and saving the machining program when the machining time difference becomes equal to or less than an allowable value by repeating the above operation.

[0011]

According to the above-mentioned method, when an imbalance exceeding a permissible value occurs in the machining time, a machining program including simultaneous machining or balance machining is created. Then, this program is checked again, and by repeating this, the imbalance of the machining time between both spindles is eliminated, and the most efficient machining program is automatically created.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. The opposing spindle lathe of this embodiment is shown in FIG.
As shown in the figure, the tool comprises a left spindle 1, a right spindle 2, a lower turret 3, and an upper turret 4, and each of the turrets 3, 4 cooperates with either of the left and right spindles 1, 2 to carry out the work. It is configured so that it can be processed.

The machining program creating device for the opposing spindle lathe is configured as shown in FIG. Input control unit 1
1 inputs various processing data such as a cutting condition, a material shape, a used spindle section, a used turret section, a used tool, and a cutting order. The processing time calculation unit 12 calculates the processing time for each of the tool rests 3 and 4 based on the input processing data. The processing time comparison unit 13 compares the processing times of the tool rests 3 and 4,
The time difference is compared with an allowable value, which is a parameter, to determine the presence or absence of imbalance.

When the imbalance of the processing time is determined, the excess process simultaneous processing determination unit 14 determines a process in which the processing time is exceeded in the longer tool post, that is, a process in which the other tool post is in a waiting state; For example, in the step of processing the inner diameter A3 in FIG. 5, whether or not simultaneous processing is possible is determined based on the processing pattern. Here, the simultaneous machining means that two tool rests simultaneously perform different processes on the same main spindle. For details, refer to Japanese Patent Application Laid-Open No. 60-294633. When simultaneous processing of the excess process is possible, the excess process simultaneous processing combination unit 15 combines the process with the processing data of the tool rest having the shorter processing time to create a processing program for both spindles.

The initial step simultaneous processing determination unit 16 determines the initial step in the tool post having the longer processing time, for example, the step of processing the end face A1 and the outer diameter A2 in FIG. It is determined whether simultaneous machining is possible. When the initial process can be simultaneously processed, the initial process simultaneous processing combination unit 17 combines the process with the processing data of the tool rest having the shorter processing time to create a processing program for both spindles.

When the initial steps cannot be processed simultaneously, the balance processing determining section 18 determines whether or not the balance processing is to be performed for the initial step in the tool post having the longer processing time. Here, the balance processing means that two tool rests share the same process with the same main spindle and perform the same process at the same time. For details, refer to the above-mentioned publication. When the initial process can perform balance processing, the balance processing setting unit 19 sets the balance processing data in the processing data of both tool rests, and creates a processing program for both spindles. The data output unit 20 outputs the processing program including the simultaneous processing and the balance processing in which the processing time difference has become equal to or less than the allowable value to a storage medium such as a floppy disk or a tape and stores the processing program.

Next, a method of creating a machining program for the work W shown in FIG. 4 will be described with reference to the flowchart of FIG. 2 and the process chart of FIG. First, in step S1, various types of processing data such as cutting conditions and material shapes are input. Next, in step S2, the processing time is calculated for each of the tool rests 3, 4 based on the processing data, and in step S3, the processing time difference ΔT is calculated.

Next, in step S4, it is determined whether or not the processing time imbalance, that is, the processing time difference ΔT is equal to or greater than an allowable value.
Then, the processing data of the lower tool post 3 having the longer processing time is retrieved. Subsequently, in step S6, it is determined whether or not simultaneous machining is possible for the process that has been exceeded in the lower tool rest 3, that is, the machining process for the inner diameter A3. If simultaneous machining is possible, in step S7, the machining process for the inner diameter A3 is changed to the upper tool. A machining program for the two spindles 1 and 2 is created in combination with the machining data of the table 4 .

As shown in the drawing, if there is only one inner diameter machining step, simultaneous machining of the inner diameter A3 is impossible.
This time, in step S8, an initial process in the lower tool post 3,
In other words, the first end face A1 from the process of processing alone
It is determined whether or not simultaneous processing is possible for the process of the second outer diameter A2. Here, the processing of the end face A1 by the lower tool post 3 and the processing of the outer diameter A2 by the upper tool post 4 can be performed at the same time. 7B, the machining program for the upper tool rest 4 is set again in the order of the outer diameter A2 of the left main spindle 1, the end face B1 of the right main spindle 2 and the outer diameter B2, and the two main spindles are changed. 1, 2 machining programs are created.

If simultaneous processing is not possible in both the excess process and the initial process, in step S10, the lower turret 3
It is determined whether or not the balance processing can be performed in the initial process of step S11.
Then, the balance processing data is set in the processing data of both the tool rests 3 and 4, and a processing program for both the spindles 1 and 2 is created.

After the machining program is created in step S7, step S9, or step S11, subsequently, in step S12, the machining time is calculated for each of the tool rests 3, 4 based on the machining program. so,
The processing time difference ΔT is calculated, and in step S14, it is determined again whether the processing time difference ΔT is equal to or larger than the allowable value. If the processing time difference ΔT is still equal to or larger than the allowable value, the process returns to step S8, and the next single processing step capable of simultaneous processing is searched again from the initial steps. Then, when the processing time difference ΔT becomes equal to or less than the allowable value, in step S15, the final processing program is stored in a storage medium such as a floppy or a tape.

Therefore, according to the method of this embodiment, by repeatedly checking the processing time difference,
As shown in (B), the unbalance of the machining time on both spindles 1 and 2 can be reduced from ΔT to ΔT ′, and the cycle time can be saved by T time. Can be created automatically.

FIG. 8 shows another example of the machining program creation method. In this example, in the flowchart of FIG.
In step S6, it is determined that simultaneous processing is possible for the excess process in the lower tool post 3, that is, the outer diameter finish A4 and the inner diameter finish A5, and in step S7, the inner diameter finish A
The machining program of the two spindles 1 and 2 is created by combining the machining process of No. 5 with the machining data of the upper tool rest 4 .

The present invention is not limited to the above embodiment, but can be embodied by appropriately changing the shape and configuration of each part without departing from the spirit of the present invention.

[0025]

As described above in detail, according to the present invention, when the machining time difference is larger than the allowable value, the machining of the tool rest having the longer machining time is performed in the opposed spindle lathe having the pair of tool rests. A simple and efficient machining program eliminates imbalance in machining time by adopting a method that searches for processes that can be processed simultaneously or processes that can be balanced from data and creates a machining program for both spindles. It has an excellent effect that it can be created.

[Brief description of the drawings]

FIG. 1 is a block diagram of a machining program creating apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a machining program creating method by the apparatus of FIG. 1;

FIG. 3 is a schematic view of an opposed spindle lathe.

FIG. 4 is a cross-sectional view showing a processed shape of a work.

FIG. 5 is an explanatory diagram showing a machined portion on a left spindle.

FIG. 6 is an explanatory view showing a machined portion on a right main shaft.

FIG. 7 is a process chart illustrating a method of creating a machining program for the work in FIG. 4;

FIG. 8 is a process chart showing another example of the machining program creation method.

[Description of Signs] 1. Left spindle, 2. Right spindle, 3. Lower turret, 4.
Upper turret, 11 ··· Input control unit, 12 ··· Processing time calculation unit, 13 ··· Processing time comparison unit, 14 ··· Excess process simultaneous processing determination unit, 15 ··· Excess process simultaneous processing combination unit, 16 ·
Initial process simultaneous processing determination unit, 17 Initial process simultaneous processing combination unit, 18 Balance processing determination unit, 19 Balance processing setting unit, 20 Data output unit, M material,
W. Work.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B23Q 15/00-15/28 B23Q 3/155-3/157 G05B 19/18-19/46 B24B 41 / 00-51/00

Claims (1)

(57) [Claims] 1. An opposed spindle lathe comprising a pair of opposed spindles and a pair of tool rests capable of machining a work in cooperation with both spindles, machining both tool rests based on machining data. Calculating the time, comparing the processing time difference with an allowable value, and, when the processing time difference is larger than the allowable value, two tool rests based on the processing data of the tool rest having a longer processing time.
Phase and the steps of creating a simultaneous machining or balance processing, including by machining programs both spindles, the machining time difference by repeating the operation allowable value but looking for simultaneously workable process or balance workable process in the same spindle Storing a machining program when the following occurs: a method for creating a machining program.