JPH01321142A - Turning method of numerical control lathe - Google Patents

Abstract

PURPOSE:To have smooth turning with a lathe by forming the shape data from the position data about several turns of the spindle of cam shaft corresponding to the spindle rotation angle of an NC lathe, and conducting the turning according to the sensing values of the spindle rotation angle. CONSTITUTION:The processing program and cam shape data DC are stored in memories 11, 15. The shape data DC consists of position data about several turns of the spindle of cam shaft corresponding to the spindle rotation angle of an NC lathe. When the processing program is started, one-block data DB is read out of the memory 11, while the processing program read out of a command selection part 13 is implemented unless there is cam shape data selection command at a sensing part 12, and if it exists, a data transfer control part 14 reads the cam shape data from the memory 15 and stores in another memory 21 in a cam shaft control part 20, and a control part 22 controls the cam shaft in accordance with the spindle rotation angle DA given by a sensor 17, and now a work 3 is processed by a cutting tool 7. Thus smooth turning with a lathe is accomplished.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a turning method that allows smooth turning of a three-dimensional shape using a numerically controlled (hereinafter referred to as NC) lathe.

(Prior Art) A conventional turning method for, for example, a cam has been carried out by copying. For example, as shown in FIG. 5, a master cam 2 is attached to the main shaft, and a tailstock 4 is pushed into the main shaft and fixed in order to bring the workpiece 3 into close contact with the master cam 2 and integrate it. Then, attach the cam follower 6 and the cutting tool 7 to the tool post 5, rotate the master cam 2, and copy the surface of the master cam 2 with the cam follower 6 (control the cam axis parallel to the X axis and the feed axis parallel to the Z axis). By doing this, the workpiece 3 can be turned using the cutting tool 7 according to the shape of the master cam 2.

In the above-described cam turning method using tracing, when the surface of the master cam 2 wears or when chips or the like enter between the master cam 2 and the cam follower 6, the accuracy of the turning process decreases. Therefore, it is necessary to remove the master cam 2, modify its shape, and reinstall it while adjusting the accuracy, and to remove chips etc. frequently, which requires a lot of effort and time for maintenance work. Was. Furthermore, there are various problems such as the need for skill to modify the shape of the master cam 2.

Therefore, in order to solve the above-mentioned problems, a cam turning method using Nc control was developed. This is a method of turning based on cam shape data.

(Problems to be Solved by the Invention) The above-mentioned NC-controlled cam turning method requires the cam shape to be defined before turning, so it is difficult to turn a cam with a three-dimensional shape that is a combination of multiple types of cam shapes. In this case, cam shape data for machining each of a plurality of cam shapes is prepared in advance and divided machining is performed.

For example, a helical cam CA as shown in Fig. 4(A)
When turning the P part of M, it is necessary to divide the P part into four parts, for example, and prepare four cam shape data that approximate the actual shape before turning. First, there was a drawback that the surface could not be processed smoothly due to cutter marks and the like.

The present invention was made in view of the above-mentioned circumstances, and an object of the present invention is to provide a turning process that can smoothly turn the surface of a three-dimensional shape that is a combination of multiple types of shapes using an NC lathe. The purpose is to provide a method.

(Means for Solving the Problems) The present invention relates to a turning method capable of smoothly turning a three-dimensional shape with an NC lathe, and the above object of the present invention is to When predetermined shape data is read out from a plurality of pre-stored shape data in the order of the shape data selection command and turned by the NC lathe according to the shape data selection command, the shape data is read out from a plurality of pre-stored shape data in the order of the shape data selection command. This is achieved by performing lathe processing in accordance with the detected value of the rotation angle of the main spindle and the shape data.

(Function) The turning method of the NC lathe of the present invention performs turning by relatively controlling the rotation of the main spindle and the feed of the camshaft, so the resulting processed product is smooth without cutter marks etc. It has a shape.

(Example) FIG. 1 is a block diagram showing an example of an NG device for realizing the turning method of an NC lathe of the present invention when turning a cam, and a machining program memory in which a machining program is stored in advance. The cam shape data selection command is selected from the one block data DB read out from 11 through the reading unit 12, and when the cam shape data selection command is issued, the transfer request signal SS is sent to the data transfer control unit 14.
The cam shape data (position data of the main shaft multiple times of the camshaft corresponding to the main shaft rotation angle) is stored in advance by the command selection section 13 outputted to the finger and the transfer request signal SS from the total selection section 13. The predetermined cam shape data DC is read out from the cam shape data memory 15, and the camshaft control unit 20
It has a data transfer control unit 14 that transfers data to. Furthermore, a memory 21 of the camshaft control section 20 that stores the cam shape data DC transferred from the data transfer control section 14;
The memory 21 is
The camshaft drive command control section 22 outputs a camshaft drive command Sx for controlling the camshaft based on the cam shape data DC from the main shaft rotation angle detector 17 and the main shaft rotation angle DA from the main shaft rotation angle detector 17.

In such a configuration, an example of its operation will be explained with reference to the flowchart of FIG. 2. The machining program and cam shape data DC to be used are stored in the memories 11 and 15, respectively (step St).

Here, for example, when turning a helical-shaped cam CAM as shown in FIG.
The rotation axis RA corresponds to the main shaft rotation angle as shown in C).
The distance between and the turning path! ! ! (Camshaft position) A1.
/h..., and is stored in the cam shape data memory 15 in the format shown in FIG. Then, it is repeatedly checked whether the machining program has started (step S2). When the machining program starts, one block data DB is read out from the machining program memory 11 (step S3), and the presence or absence of a cam shape data selection command in the one block data DB read out by the command selection section 13 is checked (step S4). If there is no cam shape data selection command in the read one block data OB, the machining program for that one block is executed in step S.
5) Check whether there is an end code (step S6); if there is no end code, return to step S3; if there is an end code, end all processing.

On the other hand, in the judgment step S4, if there is a cam shape data selection command force number in the read one block data DB, the data transfer control section 14 reads predetermined cam shape data DC from the cam shape data memory 15. It is stored in the memory 21 of the camshaft control section 20.

(Step S7). Then, the camshaft drive command control section 22
Then, the presence or absence of the feed start signal SZ from the NC control unit 16 is checked repeatedly (Step S8). If the feed start signal SZ is present, the cam shape data DC from the memory 21 and the spindle rotation angle detector 17 are The camshaft is controlled according to the main shaft rotation angle D^ (step s9), and the process returns to step S3 to repeat the above-mentioned operation.

(Effects of the Invention) As described above, according to the turning method for an NC lathe of the present invention, when turning a three-dimensional shape that is a combination of multiple shapes, the camshaft can be turned continuously without stopping. Therefore, it is possible to smoothly turn the surface of even a helical shape, thereby preventing deterioration of machining accuracy due to cutter marks or the like.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of an NG device that implements the turning method for an NC lathe according to the present invention, FIG. 2 is a flowchart explaining an example of its operation, and FIGS. 3 (8) and (B) are according to the present invention. A diagram explaining how to obtain cam shape data used in the method, FIG. 4(C) is a diagram showing the cam shape data, FIG. 4(A)
and (B) are perspective views showing a specific example to which a conventional NC lathe turning method is applied, and FIG. 5 is a plan view schematically showing an example of a conventional copying lathe. l... Main spindle, 3... Workpiece, 5... Turret, 7
... Byte, 11 ... Machining program memory, 12
...Reading unit, 13...Command selection unit, 14...Data transfer control unit, 15...Cam shape data memory, 16
...NC control unit, 17...Spindle rotation angle detector, 2
o...Camshaft control unit, 21...Memory, 22...
Camshaft drive command control unit. Applicant's agent Yuzo Yasugata Figure 2

Claims (1)

[Claims] 1. According to a shape data selection command in a machining program for a numerically controlled lathe, predetermined shape data is read out from a plurality of pre-stored shape data in the order of the shape data selection command, and lathe is performed on the numerically controlled lathe. In this case, the shape data is composed of position data for multiple rotations of the main shaft of the camshaft of the numerically controlled lathe that corresponds to the rotation angle of the main shaft of the numerically controlled lathe, and the detected value of the rotation angle of the main shaft and the shape data A method for turning using a numerically controlled lathe, characterized in that the turning is carried out according to the following.