JPH0482616A - Screw groove alignment control method for nc grinder - Google Patents

Abstract

PURPOSE:To automatically process screw groove grinding by aligning the screw groove of a work set in a machine with the screw groove of a grinding wheel with a table or a spindle moved or rotated by a specified stroke or a specified angle respectively by the use of a manual pulse generator attached to an NC device. CONSTITUTION:A table 10 or a main spindle is moved or rotated by the stroke of X or the rotating angle of theta respectively by means of MDI-3 attached to a NC device 1, so that a grinding wheel 4 is thereby aligned with a screw groove 6. The value of X or theta is then inputted into the NC device 1. Next, necessary data such as a screw data, the range of table stroke, relation between table stroke and the revolution of a spindle and the like is inputted into the NC device as information in advance. The range of the stroke of a work 5, the revolution of the spindle corresponding to the aforesaid stroke and the like are computed by an operating circuit 2 within the NC device 1 based on inputted information and the value of X or theta, so that operating commands are thereby issued to the respective motors of the NC grinder 1. By this constitution, the finishing work of the screw groove 6 can thereby be automatically processed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a workpiece in which a workpiece having a threaded groove formed therein is arbitrarily set on a grinding machine, and finishing processing of the threaded groove is automatically performed. The present invention relates to a method for controlling thread and groove alignment in an NC grinding machine.

[Prior Art] When completing a product by machining a lower thread groove in advance or finishing the thread groove of a workpiece in which a lower thread groove has been formed, it is necessary to accurately align a grindstone with the lower thread groove. Become. If this positioning is performed inaccurately, parts that are not finished threaded may remain, resulting in a defective product, or large grinding resistance will be applied to some parts during processing, resulting in the problem that high-precision processing cannot be performed. In the prior art, this thread groove alignment was performed mostly manually.

[The problem that the present invention aims to solve is that manually performing the head screw groove alignment requires considerable skill and requires a large amount of setup time.

Further, even when the thread grooves are aligned, the range to be threaded is not automatically grasped, and it becomes necessary to adjust and check the stroke range of the table and the number of rotations (rotation range) of the main shaft related thereto. Therefore, it takes a long time to finish machining the thread groove, resulting in a problem that reduces productivity.

In addition, when finishing thread grooves on workpieces of the same shape one after another, it is necessary to adjust the thread groove alignment, table stroke, and number of rotations of the spindle as described above, making it impossible to improve productivity. .

The present invention solves the above-mentioned problems by simply aligning thread grooves with MDI, and then calculating the necessary data using an NC device to automatically and easily perform finishing thread groove machining. The purpose of the present invention is to provide a method for controlling thread groove alignment in an NC grinding machine that enables the following.

[Means for Solving the Problems] In order to achieve the above objects, the present invention sets a workpiece for the lower thread groove forming method in a grinding machine equipped with an NC device, and provides a screw when finishing the thread groove. In the groove alignment control method, necessary information such as screw specifications, relationship between table feed and spindle rotation speed, distance from the machine origin to the grindstone, table origin, stroke range of the workpiece (S□ to S2), etc. is provided in advance to the NC device. At the same time, the thread grooves of the set workpiece and the grindstone are aligned using a manual pulse generator (MDI) attached to the NC device, and the table or main shaft is adjusted to the stroke ΔX or rotation angle. The movement range of the table of the workpiece and the corresponding number of rotations of the spindle are calculated by the arithmetic circuit in the NC device based on the value of △X or ΔO and the input information. The present invention is characterized by control of thread groove alignment in an NC grinder that performs groove finishing.

It turns out.

[Operation] A workpiece in which a lower thread groove is formed is arbitrarily set on the table of an NC grinding machine that has returned to the table origin position or is at a known table stroke position. In that case, the grindstone at a predetermined position and the thread groove of the workpiece usually do not match. MD attached to NC device
The table or the main shaft is rotated by the stroke ΔX or the rotation angle Δθ by I to align the grindstone and the thread groove. Said Δ
The value of X or Δθ is input to the NC device. The screw specifications and table stroke range are stored in advance in the NC device.

Necessary data such as the relationship between the table stroke and the number of rotations of the spindle is input as information. The calculation circuit in the NC device calculates the stroke range of the workpiece and the corresponding number of rotations of the main shaft based on the input information and the value of ΔX or Δθ, and issues operation commands to the motors of each part of the NC grinding machine. emits. As a result, finishing of the threaded groove is automatically performed [Embodiment] Hereinafter, an embodiment of the present invention will be described based on the drawings.

As shown in FIG. 1, the workpiece 5 is supported centrally between a headstock 7 and a spindle 8, and is rotated by a spindle rotation motor 9 (M2. pulse motor) attached to the headstock 7. The headstock 7 and the spindle 8 are fixed on a table 10. The nut 11 fixed to the table 10 is a feeder 1
2, and the feed screw 12 is rotated by a feed screw motor 14 (M, pulse motor) via a gear mechanism 13. The table 10 is slidably supported on a bed 15 and is moved in strokes by a feed screw motor 14.

On the other hand, the grindstone 4 is fixed at a predetermined position, and the grindstone rotation motor 1
6(M,).

Spindle rotation motor9. Both the feed screw motor 14 and the grindstone rotation motor 16 are NG devices! connected to 1,
It is configured so that its operation is controlled by the NC device 1.

Inside the NC device 1 are screw specifications 1, such as the diameter of the thread.

Data such as the lead, thread angle, total length (L) of the workpiece, range to be threaded (2), distances a and b (Fig. 2) from the machine origin point to the origin position of the grindstone and table are input. On the other hand, a manual pulse generator 3 attached to the NC device 1
(hereinafter referred to as MDI) sends a signal to the NC unit M1,
The main shaft rotation motor 9 and the feed screw motor 14 are configured to be operated by a necessary amount to rotate or feed the motor. That is, by operating the MDI 3, the table 10 can be moved by ΔX, and the workpiece 5 can be rotated by Δθ at that position.

The calculation circuit 2 in the NC device 1 is configured to perform calculations necessary for thread machining based on the table stroke ΔX or workpiece rotation amount Δθ operated by the MDI 3. That is, by inputting the above △X or △θ, the arithmetic circuit 2 automatically determines the stroke range of the workpiece to be thread grooved, calculates the corresponding number of revolutions of the main shaft, and operates the feed screw motor. 14 and the data to be commanded to the spindle rotation motor 9.

The details of the control method will be explained below with reference to FIGS. 2 to 4.

In FIG. 2, the grindstone 4 is fixedly placed at a distance a from the machine origin (line O-○).

On the other hand, at the position where the table 10 has returned to the table origin (A-A line), one end surface of the workpiece 5 is at a distance S from the table origin.
Suppose it is in the engineering field. Also, the workpiece 5 is located at a distance #! from the position of the distance S□ from the table origin. It is assumed that the workpiece 5 is moved to the position S2, and the thread groove 6 is ground over the entire length (L) of the workpiece 5. From the above, the thread grinding range of the workpiece 5 is the range of distance S1 and distance S2 from the table origin.

As shown in Fig. 3(a), it is assumed that the workpiece 5, which has finished finishing the thread groove 6, is at a distance S + X (the value of X is known) from the table origin. Workpiece 5 and the next workpiece 5 with the same shape but with a lower thread groove machined
′ shall be set.

In the position shown in FIG. 3(a), the position B of the grindstone 4 and the corresponding position C of the thread groove 6 match. On the other hand, Fig. 3(b)
shows the relationship between the position C' of the groove 6' corresponding to the grinding wheel 4 of the workpiece 5' that has been changed.

The workpiece 5' is at a position S
It is assumed that only the thread groove 6' is misaligned. In order to match position C' and position B', it is necessary to move table 10 or rotate work 5. Figure 3 (
C) shows the case where the table 10 is moved by ΔX.

That is, in FIG. 3(C), the table 10 is set at a position moved by S1+X0ΔX==m from the table origin, so that the positions of the threaded groove 6' and the grindstone 4 match. Therefore, the workpiece 5' is moved 5' from this position.
2-S□-X-△X = m Move to the left in the figure by a stroke of 2, and conversely from that position move S from the table origin
By returning to the position yo +

In this embodiment, the above-mentioned groove grinding is automatically controlled by the NC device 1.

The control method of this embodiment will be described above with reference to the flowchart shown in FIG.

First, a workpiece 5' that has been machined with a lower groove is set (step 101). As shown in FIG. 3(b), it is assumed that the grinding wheel 4 and the groove 6' are deviated by ΔX, and the groove alignment is performed using the MDI 3 (step 102).
Step 3 is performed by pressing a key on the keyboard by an amount corresponding to ΔX. When adjusting ΔX by moving the table 1o (step 103), the feed screw motor 14 is operated to move the table 1o by that amount. When positioning is performed by rotating the workpiece 5' (step 1o4), the table 10 is not moved and the spindle rotation motor 9 is rotated by Δθ corresponding to ΔX. Next, the value of △X or △θ is calculated by the arithmetic circuit 2 of the NC device l.
Enter. The arithmetic circuit 2 calculates the values of m and m2 shown in FIG. 3(C) based on various data previously input and stored in the NC device 1 and the value of ΔX or Δθ.

Thereby, the stroke range of the table 10 is determined (step 105).

On the other hand, once the torsion degree is determined, a proportional relational expression is established between the table stroke and the rotational speed of the workpiece 5'. Therefore, the table stroke range m□.

The number of rotations of the main shaft rotation motor 9 corresponding to m2 is determined (step 106). As a result of the above, the number of rotations of the feed screw motor 14 of the table 10 and the number of rotations of the main shaft rotation motor 9 are determined, and both motors 9 are rotated accordingly. , 14 is N
Automatic thread grinding is performed under the control of the G device 1 (step 107).

By repeating the above steps, the automatic grinding of the threaded groove 6' is completed (step 108).

[Effects of invention According to the present invention, the following effects can be achieved.

(2) Even if the lower thread groove forming product is set at random, by matching the grindstone and the thread groove using MDI, the thread groove grinding process will be performed automatically thereafter.

2) There is no need to manually adjust the thread groove alignment, table stroke range, and spindle rotation frequency.
It is possible to perform fast and highly accurate thread groove machining.

3) It is particularly effective when thread grooves are sequentially machined on workpieces of the same shape, and productivity can be improved.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of an embodiment of the present invention, FIG. 2 is an explanatory diagram for explaining the relationship between the workpiece position and each origin position, and FIG.
Figures (a) to (c) are explanatory diagrams for explaining the operation of this embodiment, and FIG. 4 is a flowchart for explaining the operation of this embodiment. 1... NC device, 2... Arithmetic circuit, 3... Manual pulse generator (MDI), 4... Grinding wheel, 2.5'...
・Workpiece, 6, 6'... Thread groove, 7... Headstock,
8...Shinjindai, 9...Main shaft rotation motor (Ml),
10...Table, 11...Nut, 12...Feed screw, 13...Gear mechanism, 14...Feed screw motor (M2), 15...Bed, 16...Wheelstone rotation motor (M,).

Claims (1)

[Claims] In a thread groove alignment control method when a workpiece with a lower thread groove already formed is set on a grinding machine equipped with an NC device and the thread groove is finished, the NC device is programmed with the thread specifications, table feed, and spindle rotation speed in advance. relationship, the distance from the machine origin to the grinding wheel, the table origin, the workpiece stroke range (S_
A manual pulse generator (MDI) attached to the NC device inputs necessary information such as 1 to S_2) and aligns the thread grooves of the set workpiece with the grindstone.
The table or spindle is moved by the stroke ΔX or the rotation angle Δθ using A method for controlling thread groove alignment in an NC grinding machine, characterized in that a calculation is performed by an arithmetic circuit in an NC device to perform finishing machining of thread grooves.