JP2003076409A - Numerical control grinding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a numerical control grinding machine capable of appropriately and quickly setting the grinding feeding speed data among the grinding conditions. SOLUTION: A RAM 25 connected to a CPU 19 of a NC device 18 for controlling a grinding machine is provided with a grinding condition data area, a grinding efficiency data area, and a computing equation storage area of the grinding efficiency and the grinding feeding speed. When a diameter of a work before grinding is D1 (mm), a diameter after the grinding is D2 (mm) and the grinding time is t, grinding efficiency Z (mm<2> /min) is expressed with equation 1; Z= (π/4)×[D1<2> -D2<2> ]}÷t, and the grinding feeding speed V (mm/min) is expressed with equation 2; V= (D1-D2)/2}÷t. The CPU 19 computes the grinding feeding speed V (mm/min) on the basis of both the equations 1 and 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a numerically controlled grinding machine which can easily set a grinding feed speed among grinding conditions.

[0002]

2. Description of the Related Art A numerically controlled grinder for grinding the outer peripheral surface of a rod-shaped work such as a crankshaft or a camshaft is a headstock that supports and rotates the work at a predetermined position, and a rotary grindstone that grinds the work. And a grinding stone head provided with a numerical control of the feed speed of the grinding stone head to grind a workpiece.

As a preparatory work for the work to be ground, a worker creates a grinding program suitable for the work to be ground. This is created by the type of grindstone required for grinding, its diameter, work material, shape, dimensions, and other work data, grinding allowance for the work, grinding condition data such as the number of revolutions of the grindstone and the work, and the grinding feed rate of the grindstone. Is performed according to the screen displayed on the display.
Then, the grinding program is automatically set by the control device based on the above-mentioned data.

[0004]

However, it often depends on the experience of the operator to determine the input data for determining the grinding conditions for creating a highly accurate grinding program. In order to determine the input data that determines the grinding condition with higher accuracy, experienced workers and Shun often changed the grinding condition, repeated trial grinding, and repeated thought and error.

The most difficult part of the input data is the grinding feed rate of the wheel head, and the operator repeats the trial grinding many times in order to set the optimum grinding feed rate with high accuracy according to the type of work. I was going. Depending on the specifications of the grinder, the type of work, or the grinding process, the grinding efficiency is important in determining the feed rate among the grinding conditions. The grinding efficiency refers to a grinding allowance cross-sectional area per unit time when grinding a grindstone with a width of 1 mm, and refers to an optimum grinding ability of a grinding machine in a grinding process. Although the grinding efficiency is known empirically, the grinding feed rate was not set in consideration of the relationship with the grinding efficiency. As a grinding condition of the grinder, a grindstone diameter, a grindstone rotation speed, a work diameter, a work rotation speed, a grinding start point, a grinding order, and the like are relatively easily determined. However, it was difficult to determine the "grinding feed rate" related to the grinding efficiency considering the sharpness of the grindstone, and thought and error were repeated, and setting an appropriate grinding program was very troublesome.

By the way, among the precisions required for a grinding machine, the roundness, burning, hardness decrease, etc. of a work are greatly influenced by the above-mentioned grinding efficiency. Further, the grinding efficiency itself is greatly influenced by the coolant, the sharpness of the grindstone, and the like. The present invention displays the grinding efficiency as a database on the screen, and determines the grinding feed rate among a plurality of elements of the grinding conditions related thereto, whereby the setting of the grinding program can be appropriately and quickly performed. It was created with a focus on it.

An object of the present invention is to provide a numerically controlled grinding machine which solves the problems existing in the above-mentioned conventional techniques and which can easily set a grinding feed rate and rapidly create an appropriate grinding program. Especially.

[0008]

In order to solve the above problems, the invention according to claim 1 provides a support mechanism for supporting a work, a whetstone base for supporting a rotary grindstone for grinding the work, and a whetstone. In a numerically controlled grinder that grinds a work by controlling the movement of the table or the work support mechanism by numerical control, grinding condition data input means for inputting the grinding condition data of the work, and the grinding efficiency data of the work Based on the grinding efficiency data input means for inputting and the grinding efficiency data input by the grinding efficiency data input means, the feed speed data calculating means for calculating the moving speed of the grinding wheel head, that is, the grinding feed speed data using an arithmetic expression And a display means for displaying the grinding condition data, the grinding efficiency data, the feed rate data and the like.

According to a second aspect of the present invention, in the first aspect, the diameter D1 (mm) of the workpiece before grinding and the diameter D2 of the workpiece after grinding.
(Mm) and grinding time t, grinding efficiency Z (mm ² /
min) is Z = {(π / 4) × [D1 ² −D2 ² ]} ÷ t (1) is represented by the above calculation formula (1), and the grinding feed rate V (mm
/ Min) is V = {(D1-D2) / 2} ÷ t (2) is represented by the arithmetic expression (2), and both arithmetic expressions (1),
The gist is that the feed speed data calculating means calculates the grinding feed speed V (mm / min) based on (2).

According to a third aspect of the present invention, in the second aspect, the data of the grinding efficiency Z (mm ² / min) is preset as a database according to the type of the work material, and the work material is set. When selected and designated, the corresponding data is selected from the database, and the grinding feed speed is calculated based on the selected data.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the numerical control grinding machine of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the work support 1 is mounted on the upper surface of one side of the base 2 in a horizontal direction (Z
Direction) is supported so as to be movable. The headstock 3 is disposed on the upper surface of the work support base 1 and serves as a work W such as a camshaft.
A spindle motor 5 including a spindle 4 for detachably supporting one end and a servomotor for rotating the spindle 4 is provided.

The holder 6 is disposed on the upper surface of the work support base 1 so that the distance between the holder 6 and the work spindle 4 can be adjusted freely, and the work W is attached to the work spindle 4.
And the holder 6 are rotatably and detachably supported so as to extend in the Z direction. Then, the work W is rotated in a predetermined direction as the spindle motor 5 is driven in this supported state. The encoder 7 is attached to the spindle motor 5, and a detection signal of the motor rotation angle from the encoder 7 is input to an NC device 18 described later.

The grindstone base 8 is supported on the base 2 so as to be movable in the horizontal direction (X direction) orthogonal to the axis of the work W. A moving motor 9 composed of a servo motor is attached to a side portion of the base 2, and the moving motor 9 rotates the ball screw 10 to move the grindstone base 8 in a direction to approach or separate from the work W. The encoder 11 is attached to the moving motor 9, and a detection signal from the encoder 11 is input to an NC device 18 described later. The rotary grindstone 12 is rotatably supported by a spindle 13 at one end of the grindstone base 8 so as to face the work W. The grindstone motor 14 is disposed on the grindstone base 8, and the grindstone motor 1
4, the rotary grindstone 12 is rotated in one direction via the pulleys 15 and 16 and the belt 17. In the present embodiment, the moving motor 9 and the ball screw 10
The moving means of the rotary grindstone 12 is constituted by the above.

The NC (numerical control) device 18 constitutes a control means and controls the operation of the entire grinding machine.
The NC device 18 includes a central processing unit (CPU) 19 that performs various kinds of arithmetic processing. The NC device 18 also includes a random access memory (RAM) 25 for temporarily storing various information and a read only memory (ROM) 26 for storing programs for controlling the operation of the entire grinding machine. I have it.

The CPU 19 of the NC device 18 is connected to the spindle motor 5 and the encoder 7 by the servo motor drive circuit 20 and the interface 22, and the servo motor drive circuit 21 and the interface 2 are connected.
2 is connected to the moving motor 9 and the encoder 11. The servo motor drive circuits 20 and 21 are CPUs.
It is a circuit for inputting a command from 19 to numerically drive the spindle motor 5 and the moving motor 9 respectively. In addition, the servo motor drive circuits 20 and 21 include encoders 7,
The number of revolutions of the work W and the rotary grindstone 12 detected by 11 is fed back.

As shown in FIG. 2, the RAM 25 has an NC data area 25 of the work W input from the operation panel 28.
1. A grinding condition data area 252 for recording grinding condition data of the work W is provided. In addition, in RAM25,
A grinding efficiency data area 253 for storing grinding efficiency data,
A grinding efficiency calculation formula storage area 254 for storing a calculation formula (1) of a grinding efficiency and a calculation formula (2) of a grinding feed rate, which will be described later.
Feed rate data storage area 25 for storing feed rate data
5 are provided.

As shown in FIG. 1, an operation panel 28 is connected to the CPU 19 via an interface 27. The operation panel 28 is provided with a keyboard 29 that constitutes a means for inputting various data and a display 30 that constitutes a means for displaying various data.

As shown in FIG. 4, the CPU 19 is equipped with a feed rate data calculation means 191. The feed speed data calculating means 191 calculates the feed speed data based on the grinding condition data read from the grinding condition data area 252 and the grinding efficiency calculation expression storage area 254 and the calculation expressions (1) and (2). Has become. The calculated feed speed data is stored in the speed data storage area 255.

By the way, the arithmetic expressions (1) and (2) are set as follows. Diameter D1 of the workpiece before grinding
(Mm), the diameter D2 (mm) after grinding, and the grinding time t, the grinding efficiency Z (mm ² / min) is Z = {(π / 4) × [D1 ² −D2 ² ]} ÷ t · .. (1) It is represented by the above arithmetic expression (1). The grinding efficiency Z is the grinding allowance cross-sectional area (mm ² ) per unit time (1 minute) in the case of grinding a 1 mm width of a grindstone as described in the prior art.
That is.

The feed rate V (mm / mi) of the rotary grindstone
n) is V = {(D1-D2) / 2} / t ... (2) It is represented by the said arithmetic expression (2). The feed rate V of the rotary grindstone V (mm / mi) is calculated by the feed rate data calculation means 191 based on both equations (1) and (2).
n) is calculated.

FIG. 5 is a graph showing the relationship between the time on the horizontal axis and the position of the wheel head on the vertical axis. Approach time until time t1, rough grinding from t1 to t2, t
2 to t3 indicate intermediate finishing grinding, and t3 to t4 indicate finishing grinding. Since the feed rate is different in each grinding step, even when the same workpiece W is ground, a plurality of types of grinding efficiency data are prepared in advance according to each grinding step and stored in the grinding efficiency data area 253 as a database.

Next, the operation of the numerically controlled grinding machine configured as described above will be described with reference to the flowchart of FIG. First, the keyboard 29 of the operation panel 28 is operated to input the grinding condition data such as the material, diameter, or shape of the work W to be ground on the screen of the display 30. This grinding condition data is displayed on the display 30 as shown in FIG. 3, for example.

After that, the grinding efficiency data is read from the grinding efficiency data area 253 of the RAM 25, and the above-mentioned arithmetic expressions (1) and (2) of the grinding efficiency and the grinding feed speed are read out from the grinding efficiency arithmetic expression storage area 254 to perform both operations. The grinding feed speed data V is calculated based on the equations (1) and (2).

In the finishing process of the work, the grinding efficiency is 1200 mm ² / min and the work diameter before grinding is 5 mm.
The following is an example of the calculation of the grinding time t for finishing to 0.00 mm and the work diameter after grinding of 49.75 mm and the feed speed V of the grinding wheel head.

Z = {(π / 4) × [D1 ² −D2 ² ]} ÷ t (1) 1200 = {(π / 4) × (50.00 ² −49.75 ² )} ÷ t t ≈ 0.016 min (0.96 sec) V = {(D1-D2) / 2} ÷ t (2) V = {(50.00−49.75) / 2} ÷ 0.016 ≈ 7.8 mm / min Next, the grinding program is set by calculating the feed rate data, and the workpiece W is ground by the numerical control grinder based on this grinding program.

In the data list of FIG. 3, the material of the work, the diameters D1 and D2 of the work before and after grinding, the number of revolutions of the work, the type of grindstone, the diameter of the grindstone, the number of revolutions of the grindstone, the grinding efficiency Z, the grinding time t, and The feed speed V obtained by the calculation is displayed.

The effects of the numerically controlled grinding machine configured as described above will be described together with the configuration. (1) In the above embodiment, the arithmetic expressions (1) and (2) of the grinding efficiency and the grinding feed speed are stored in advance in the grinding efficiency data area 253 and the grinding efficiency arithmetic expression storage area 254, and the feed is performed based on both the arithmetic expressions. The speed data V was calculated, and the grinding conditions were set based on this data. Therefore, the feed speed V can be set appropriately and easily, and the work efficiency can be improved. In other words, the grinding efficiency data is set in advance, stored as a database, and the grinding feed rate is obtained. Therefore, the grinding feed rate can be appropriately and quickly obtained from the grinding efficiency, and the grinding conditions can be set. It can be done properly and quickly.

(2) In the above embodiment, the grinding efficiency is individually set according to various data of the work and various data of the grinder, and the grinding feed rate suitable for the work to be ground is set from these conditions. I tried to ask. Therefore, it is possible to properly and easily set grinding programs for different kinds of works.

The above embodiment may be modified as follows. The data corresponding to the work W to be ground may be selected and set manually or automatically from a plurality of preset grinding efficiency databases.

The data of the grinding efficiency Z (mm ² / min) is preset as a database according to the type of the material of the work and the grinding process. When the material of the work and the grinding process are selected and designated, they correspond to the data. Data may be selected from a database, and the feed rate of the grinding wheel head may be calculated based on the selected data.

The rotating grindstone 12 may be held at a predetermined position and the work W may be moved to perform the grinding work.

[0033]

As described above in detail, according to the present invention, by setting the grinding efficiency among the grinding conditions according to the work to be ground, an appropriate grinding feed speed can be easily set by calculation. it can.

[Brief description of drawings]

FIG. 1 is a schematic block circuit diagram showing an embodiment of a numerical control grinding machine according to the present invention.

FIG. 2 is an explanatory diagram of a random access memory.

FIG. 3 is an explanatory diagram of a work table.

FIG. 4 is an explanatory diagram of a central processing unit.

FIG. 5 is a graph illustrating a grinding operation.

FIG. 6 is a flowchart showing an operation of setting feed speed data prior to a grinding operation.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Work support stand, 3 ... Shaft stand, 4 ... Spindle, 8 ... Grindstone stand, 9 ... Movement motor, 12 ... Rotating grindstone, 14 ... Grindstone motor, 18 ... NC device, 19 ... CPU, 25 ... RA
M, 26 ... ROM, 28 ... Operation panel, 29 ... Keyboard,
30 ... Display, 191 ... Feed speed data calculation means, 251 ... NC data area, 252 ... Grinding condition data area, 253 ... Grinding efficiency data area, 254 ... Grinding efficiency arithmetic expression storage area, 255 ... Speed data storage area.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3C034 AA01 CB01 DD07                 3C043 AC21 CC03                 3C049 AA02 AA11 AB01 BB06 BC01                       BC02 CA01 CB01 CB03                 5H269 AB07 BB07 CC01 DD01 EE11                       EE25

Claims (3)

[Claims] 1. A support mechanism for supporting a work, a grindstone supporting a rotary grindstone for grinding a work, and a numerical value for controlling the movement of the grindstone base or the work supporting mechanism by numerical control to grind the work. In the control grinding machine, the grinding condition data input means for inputting the grinding condition data of the work, the grinding efficiency data input means for inputting the grinding efficiency data of the work, and the grinding efficiency data input by the grinding efficiency data input means Based on the moving speed of the wheel head, that is, feed speed data calculating means for calculating grinding feed speed data using an arithmetic expression, and display means for displaying the grinding condition data, grinding efficiency data, feed speed data, and the like. A numerical control grinding machine characterized by being equipped. 2. When the diameter D1 (mm) of the workpiece before grinding, the diameter D2 (mm) after grinding, and the grinding time t are defined in claim 1, the grinding efficiency Z (mm ² / min) is Z = { (Π / 4) × [D1 ² −D2 ² ]} ÷ t (1) The grinding feed rate V (mm
/ Min) is V = {(D1-D2) / 2} ÷ t (2) is represented by the arithmetic expression (2), and both arithmetic expressions (1),
A numerical control grinder in which the feed speed data calculating means calculates the grinding feed speed V (mm / min) based on (2). 3. The grinding efficiency Z (m according to claim 2,
m ² / min) data is preset as a database according to the type of work material, and when the work material is selected and designated, the corresponding data is selected from the database, and according to this selected data A numerically controlled grinding machine adapted to calculate the grinding feed rate.