JPH0618754Y2 - NC machine tool feed control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a feed control device for an NC machine tool capable of manual operation. More specifically, the present invention relates to a feeding device that moves in biaxial directions orthogonal to each other by using an arbitrary movement direction switch.

[Background technology and its problems]

In an NC machine tool such as a horizontal boring and milling machine, a table on which a work is placed and a tool are orthogonal to each other in a biaxial direction (for example, an X-axis and a Y-axis direction) according to a preset program, depending on a machining location of the work. In some cases, it may be more efficient to manually perform the cutting process while relatively moving the table and the tool in the biaxial direction, rather than performing the cutting process while relatively moving the table and the tool.

Conventionally, in this type of NC machine tool, in order to perform a manual operation, it is necessary to set a feed speed and then select a moving direction for each X and Y axis, for example, + X direction or −X direction for the X axis. Met.

This will be described for the X-axis manual operation with reference to FIG. First, after setting the feed speed by the speed setting volume 1, when the moving direction is selected by the direction selection switches 2A, 2B such as two push button switches or changeover switches, the pulse generator 3 sets it by the speed setting volume 1. A pulse corresponding to the selected feed speed and the moving direction selected by the direction selection switches 2A and 2B is output. The pulse is generated by the positioning control circuit 4 and the speed control circuit 5.
Is given to the motor 6 through the motor 6 to rotate the motor 6 in the command direction and at the command speed. In the figure, 7 is a speed detector such as a tachometer generator that detects the rotation speed of the motor 6, and 8 is the difference between the speed detection value from the speed detector 7 and the speed command value from the positioning control circuit 4. An adder 9, a feedback unit for obtaining the X-axis movement amount from the rotation angle of the motor 6 and giving it to the positioning control circuit 4 is a manual pulse generator (MPG) for sending a pulse to the positioning control circuit 4.

However, in such a manual operation operation, since the direction selection switches 2A and 2B must be operated for each axis (X and Y axes), two-axis simultaneous operation must be performed with both hands. Therefore, the curve operation in which the direction changes sequentially is a very difficult operation. Moreover, it was impossible to change the speed while performing these operations.

[Purpose of device]

Here, an object of the present invention is to solve such a conventional problem, to easily perform a manual operation including a curve operation which has been impossible in the past, and to perform an efficient and accurate positioning with an NC machine tool. The present invention is to provide a feed control device.

[Means for solving problems]

Therefore, the configuration of the present invention is an NC machine tool in which movements in two axial directions orthogonal to each other are performed by motors, respectively. The NC machine tool has an operation lever that can be tilted in any direction, and the operation lever can be tilted depending on the tilting direction. An arbitrary movement direction switch for generating a signal having a level proportional to the speed of each axis component according to the tilt angle of the operating lever, and each of the arbitrary movement direction switches. A direction discriminating circuit that discriminates the rotation direction of each shaft motor based on the information about the direction of the axis component, and a maximum feed speed switch that selects the maximum feed speed when the tilt angle of the operation lever is maximum from a plurality of types. The switch and the maximum feed speed selected by the maximum feed speed changeover switch are set to the signal level proportional to the speed of each axis component from the arbitrary movement direction switch. A speed command means for converting to a rotation speed according to the degree range, and a control means for driving each of the axis motors based on the rotation speed command from the speed command means and the rotation direction command from the direction determination circuit. It is characterized by having done.

Therefore, if the operation lever of the arbitrary movement direction switch is tilted in an arbitrary direction, the table and the tool relatively move in the tilting direction of the operation lever and at a speed according to the tilt angle of the operation lever. The table and the tool can be quickly moved relative to a desired position along a desired locus.

In addition, the maximum feed speed changeover switch allows the maximum feed speed when the tilt angle of the operating lever is maximum to be selected from multiple types, so first set the maximum feed speed to a large value with the maximum feed speed changeover switch. If it is moved and the maximum feed speed is switched to a small value before the final position to move to the final position, efficient and accurate positioning can be performed.

〔Example〕

An embodiment in which the present invention is applied to a horizontal boring and milling machine will be described below with reference to the drawings.

Fig. 1 shows the appearance of the milling machine. The base 11 has
The table 14 has two axial directions (X
The shaft head 16 is provided so as to be movable in the axial direction and the Z-axis direction, and the spindle head 16 is provided behind the table 14 via the column 15 with respect to the two axes in which the table 14 moves, that is, the X-axis direction and the Z-axis direction. Are provided so as to be able to move up and down in directions (Y-axis direction) orthogonal to each other. A main spindle 17 is rotatably supported by a main spindle head 16 in parallel with the Z axis, and a tool 1 for cutting a work (not shown) set on the table 14 at the tip of the main spindle 17.
8 is replaceably attached.

FIG. 2 shows a drive mechanism for moving the table 14 in the X-axis direction. The drive mechanism that moves the table 14 in the Z-axis direction and the drive mechanism that moves the spindle head 16 in the Y-axis direction are basically the same as the configurations described below, and thus description thereof is omitted.

The drive mechanism includes a feed screw shaft 21 supported by the base 11 in parallel with the X-axis direction and screwed with the table 14.
A motor 23X connected to one end of the feed screw shaft 21 via gears 22A and 22B is included. A speed detector 24X such as a tachometer generator that detects the rotation speed of the motor 23X is directly connected to the motor 23X.
A position detector 25X that detects the position of the table 14 in the X-axis direction is provided along the moving direction of the table 14.

FIG. 3 shows a control circuit for controlling the movement of the table 14 in the X-axis direction and the movement of the spindle head 16 in the Y-axis direction. The control circuit includes a joystick 31 as an arbitrary movement direction switch, an X-axis motor drive controller 32X for driving the X-axis motor 23X in accordance with a signal of the X-axis component from the joystick 31, and a Y from the joystick 31. The Y-axis motor drive controller 32Y drives the Y-axis motor 23Y according to the signal of the axis component.

As shown in FIGS. 4 and 5, the joystick 31 has an operation lever 42 which is always held in an operation box 41 so as to be able to return to an upright state and tilted in any direction with the upright state as a neutral position. It is configured to generate a signal regarding the direction and speed of each axis (X and Y axis) component according to the tilt direction and angle of the operation lever 42. For example, when the operation lever 42 is tilted in the + X and -Y directions, a positive voltage proportional to the tilt angle of the operation lever 42 in the + X direction is applied to the X-axis motor drive control circuit 32X in the -Y direction of the operation lever 42. Negative voltage proportional to the tilting angle of is applied to the Y-axis motor drive control circuit 32Y. In addition, the operation box 41 includes an operation lever 42.
In addition to the above, a maximum feed speed changeover switch 38 that can select the maximum feed speed is provided, and whether or not the signal of each axis component from the joystick 31 is input to the motor drive control devices 32A and 32B of each axis is determined. A selection switch 43 for selection is provided.

The motor drive control devices 32X, 32Y determine the information about the direction of each axis component based on the signal of each axis component from the joystick 31, that is, the rotation direction of each axis motor 23X, 23Y by the positive / negative of the voltage. Direction discriminating circuits 33X and 33Y, speed command means 39X and 39Y for instructing the rotation speed of each axis motor 23X and 23Y based on signals of each axis component from the joystick 31, and rotation from these speed command means 39X and 39Y. Control means 4 for driving the motors 23X, 23Y of the respective axes based on the speed command and the rotation direction command from the direction determination circuits 33X, 33Y.
0X, 40Y.

The respective speed command means 39X, 39Y generate VF converters (voltage / frequency converters) 34X, 34Y for generating a pulse corresponding to the voltage level of each axis component signal from the arbitrary movement direction switch 31, and This VF converter 34X, 34
The frequency divider circuit 35X, which divides the pulse from Y according to a preset range and gives it to the control means 40X, 40Y,
35Y. The frequency dividing circuit 35X,
When the tilting angle of the operating lever 42 of the joystick 31 is maximum with respect to any axis, 35Y sends a pulse corresponding to the value selected by the maximum feed speed changeover switch 38 to the control means 40X, 40Y for that axis. It is designed to output.

The respective control means 40X, 40Y include the position detectors 25X,
Positioning control circuit 36X, which obtains the difference between the position feedback signal from 25Y and the position command value, and outputs this together with the rotation speed command from the direction determining circuits 33X and 33Y and the rotation speed command from the frequency dividing circuits 35X and 35Y.
36Y, and the motors 23X and 24Y for the respective axes are driven so that the difference between the speed signals from the speed detectors 24X and 24Y and the speed command values from the positioning control circuits 36X and 36Y becomes zero and according to the rotation direction command. And speed control circuits 37X and 37Y.

FIG. 6 shows a specific configuration of the positioning control circuit. In addition,
Since the positioning control circuits 36X and 36Y for each axis have the same configuration, the positioning control circuit 36X for the X axis will be described here.

The control circuit 36X has a waveform shaping direction discriminating circuit 61X for inputting a command pulse relating to the rotational speed from the frequency dividing circuit 35X and a rotational direction command (CWC, CCWC) from the direction discriminating circuit 33X, and another manual feed. A VF converter 62X that receives a velocity reference signal, a switching circuit 63X that switches signals from the VF converter 62X and the waveform shaping direction determination circuit 61X, and the position detector 25.
The direction discrimination frequency divider circuit 64X which receives the position feedback signal from X, the adder 65X which obtains the difference between the signal from this direction discrimination frequency divider circuit 64X and the command value, and the value of this adder 65X are counted. It comprises a deviation counter 66X, a D / A converter 67X which converts the count value of the deviation count 66X into an analog signal and outputs it to the speed control circuit 37X, a clock pulse oscillation circuit 68X, and a power supply circuit 69X. There is.

Next, the operation of this embodiment will be described.

When the operating lever 42 of the joystick 31 is tilted in any direction, the joystick 31 outputs the voltage of each axis component according to the tilting direction and the angle of the operating lever 42, and the motor drive control devices 32X and 32Y of each axis are output. Is entered.

In the motor drive control devices 32X and 32Y for the respective axes, the direction determination circuits 33X and 33Y determine the rotation direction based on whether the voltage is positive or negative and output it to the control means 40X and 40Y, while the speed command means 39X and 39Y are set to the voltage level. The corresponding rotation speed command pulse is output to the control means 40X, 40Y.

The respective control means 40X, 40Y include motors 23X, 2 for the respective axes.
3Y is rotated in the commanded rotation direction and at a speed according to the command pulse.

As a result, the motors 23X and 23Y of the respective axes are rotated in the instructed rotation direction and at the speed, so that the table 14 and the tool 18 are moved in the tilting direction of the operating lever 42 and at the speed corresponding to the tilting angle of the operating lever 42. Is moved relative to.

Therefore, according to the present embodiment, if the operation lever 42 of the joystick 31 is tilted in any direction, the operation lever 4
Since the table 14 and the tool 18 move relative to each other in the tilting direction of 2 and at a speed according to the tilting angle of the operating lever 42, one-handed operation may be performed even when two-axis simultaneous operation is performed, and curved operation is also easily performed. be able to.

Further, when the tilting angle of the operating lever 42 is maximized, the table 14 and the tool 18 are moved according to the speed set by the maximum feed speed changeover switch 38. If the maximum feed rate is set to a large value by the feed rate changeover switch 38 and moved, and the maximum feed rate is changed to a small value before the final position to move to the final position, the table 14 and the tool 18 are positioned efficiently and accurately. can do.

In the above embodiment, the joystick 31 is used to move the table 14 in the X-axis direction and the spindle head 16 in the Y-axis direction.
Either one of the spindle head 16 and the spindle head 16 may be moved in two axial directions orthogonal to each other.

Further, in the above-described embodiment, the example applied to the horizontal boring and milling machine has been described, but the present invention is not limited to this, and can be applied to NC machine tools in general.

[Effect of device]

As described above, according to the present invention, it is possible to provide a feed control device for an NC machine tool that can easily perform a manual operation including a curve operation, which has been impossible in the past, and can perform efficient and accurate positioning. it can.

[Brief description of drawings]

FIG. 1 is a perspective view showing an appearance of an embodiment of the present invention, FIG. 2 is a view showing a drive mechanism of a table, FIG. 3 is a block diagram showing a drive controller, and FIG. 4 is an appearance of a joystick. A front view, FIG. 5 is a side view thereof, FIG. 6 is a block diagram showing a positioning control circuit, and FIG. 7 is a block diagram showing a conventional motor control device. 14 ... table, 23X, 23Y ... motor, 31 ...
... Joystick, 33X, 33Y ... Direction discriminating circuit, 34X, 34Y ... VF converter, 35X, 35Y ...
… Dividing circuit, 36X, 36Y …… Positioning control circuit, 3
7X, 37Y ... speed control circuit, 38 ... maximum feed speed changeover switch, 39X, 39Y ... speed command means, 40
X, 40Y ... Control means, 42 ... Operation lever.

Claims (2)

[Scope of utility model registration request] 1. An NC machine tool in which movements in biaxial directions orthogonal to each other are performed by motors respectively, and an operation lever which can be tilted in an arbitrary direction is provided, and each of the above-mentioned respective operation levers is tilted according to the tilting direction. An arbitrary movement direction switch that includes information about the direction of the axis component and that generates a signal having a level proportional to the speed of each axis component according to the tilt angle of the operating lever, and of each axis component from the arbitrary movement direction switch. A direction discriminating circuit for discriminating the rotation direction of each of the axis motors based on the information on the direction, a maximum feed rate changeover switch for selecting a maximum feed rate from a plurality of types when the tilt angle of the operation lever is maximum, A signal level proportional to the speed of each axis component from the arbitrary movement direction switch is set to the maximum feed speed range selected by the maximum feed speed changeover switch. A rotation speed command means for converting the rotation speed according to the rotation speed command from the speed command means and a rotation direction command from the direction determination circuit to drive each of the axis motors. Characteristic NC machine tool feed control device. 2. In the claim 1 of the utility model registration claim,
The speed command means generates a pulse according to a signal level of each axis component signal from the arbitrary movement direction switch, and a pulse from the voltage / frequency converter to the maximum. A feed control device for an NC machine tool, comprising: a frequency dividing circuit that divides the frequency in accordance with a maximum feed speed range selected by a feed speed changeover switch and applies the divided frequency to the control means.