JPH0471719B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a head control method for returning the head of a numerically controlled automatic drafting machine to a fixed origin set on a table.

As shown in FIG. 1, the conventional system includes an X deceleration command switch 4, an X origin stop command switch 6, and a -X stroke end limit switch 8 on the table 2 side, and a Y deceleration command switch 12 on the Y rail 10 side. , a Y origin stop command switch 14, and a -Y stroke end limit switch 16.

To return the pen head 18 to the origin A set on the table 2, pulses are supplied from the controller to the X pulse motors 20 and 22, and the X cursors 24 and 26 are moved along the X rails 28 and 30 in the -X axis direction. Drive at the maximum speed FT and supply pulses to the Y pulse motor 32 to move the Y cursor 34 to Y
It is driven along the rail 10 in the −Y-axis direction at the maximum speed FT. When the X cursor 24 turns on the switch 4, a detection signal is sent from the switch 4 to the controller.Based on this, the controller reduces the rotational speed of the pulse motors 20 and 22, and the X cursor 2
4.26 is decelerated to speed FB. The speed FB is a speed at which the X cursors 24 and 26 can stop without error in response to a motor stop command.

Next, when the X cursor 24 contacts the switch 6 and turns it on, the controller sends the X pulse motor 2 based on the detection signal of the switch 6.
A stop command is issued at 0.22 and the X cursor moves to 24.
26 stops. Similarly, the Y cursor 34 is also decelerated by the switch 12 and stops when the switch 14 is turned on. In this way, the pen position of the pen head 18 is set to the fixed origin A.

In addition, switches 8 and 16 are XY cursors 24 and 3.
XY when 4 accidentally exceeds switch 6.14
This is for stopping the cursors 24 and 34.

As is clear from the above explanation, switch 4.
Since switches 6, 12, and 14 are set in the effective drawing range, switches 4, 6, 12, and 14 can be operated by cursors 24 and 34 even when the cursor detection signal is not needed, and switch 4・
There is a defect that unnecessarily degrades the mechanical and electrical performance of switches 6, 12, and 14, and the cursor has moved beyond the home stop command switches 6, 14, causing the cursor to move between the switches 6, 14 and the stroke end switches 8, 16. If the cursor is stopped at the cursor position, there is a defect in that the cursor cannot be returned to the origin from this state. Although the automatic drawing machine described above moves the Y-rail 10 in the X-axis direction along the table 2, the same applies to automatic drawing machines that move the table in the X-axis direction with respect to the fixed Y-rail. I can say that.

An object of the present invention is to provide a fixed origin return method that eliminates the above-mentioned defects.

The configuration of the present invention will be explained below with reference to the accompanying drawings.

FIG. 3 shows a part of the electronic circuit constituting the controller. In the figure, 8' is a -X stroke end switch, which is the switch 8 in FIG.
corresponds to In the present invention, switches corresponding to switches 4 and 6 in FIG. 1 are not used. 4
0 is a differential circuit that outputs a pulse 42 when the level at the input terminal changes from High to Low, 44 is an inverting amplifier, and 50 is a register that stores the fixed origin command from line 48. 52・
54 and 56 are AND gate circuits, 58 is a pulse generator, and the X pulse motor 2 is connected from the controller.
In response to the stop command to 0.22, X pulse motor 2
0.22 is set to oscillate a pulse with a frequency that can be stopped without error. Said line 48
The fixed origin command input to the controller can be issued from the origin return button switch provided on the control panel of the automatic drafting machine, or the origin return command can be input by means such as punching on the input tape to the controller. However, a fixed origin command may appear on line 48 based on this command.
Although the above is for the X-axis, a similar circuit is also provided on the -Y stroke end limit switch 16' side. The fixed origin command is “1”
signal, which is supplied to line 48 when the return-to-home button switch is pressed or by a return-to-home command from the input tape. With this “1” fixed origin command, the X cursor 24 and Y cursor 3
4 moves towards the origin at maximum speed in the -XY axis direction,
The fixed origin command "1" signal is supplied to the line 48 until the X cursor 24 and Y cursor 34 reach the -X stroke end limit switch 8' and -Y stroke end limit switch 16'. It is configured.

In the above configuration, first, the pen head 18
When the pen 36 returns to the fixed origin A, press the origin return button switch. This causes line 4
8, a fixed origin return command of "1" appears. This fixed origin return command is supplied to one input terminal of the AND gate circuit 52 and is stored in the register 50. When the -X stroke end limit switch 8' is off, the AND gate circuit 52
A signal of "1" is input from the inverting amplifier 44 to the other input terminal. Therefore, when the fixed origin return command is input to one input terminal of the AND gate circuit 52 and the switch 8' is OFF, the AND is established and the -X-axis direction movement command from the AND gate circuit 52 is The pulse is sent to the pulse motor drive circuit, and the pulse of the -X axis direction component is supplied from the controller to the X pulse motors 20 and 22. As a result, the X cursors 24 and 26 move along the X rails 28 and 30 in the -X axis direction at the maximum speed FT.
When the X cursor 24 contacts the switch piece of the -X stroke end switch 8' and the switch 8' is turned on (ON), the output terminal of the inverting amplifier 44 becomes "0".
As a result, the AND gate circuit 52 outputs a -X movement stop command of "0" to the X motor drive circuit. At this time, due to its inertia, the X cursor 24 is -
It travels a certain distance Z (see FIG. 5) in the X-axis direction and stops. When the movement of the X cursor 24 in the -X axis direction is completed, this end signal appears on the line 60 as a "1" signal. And gate 56
The "1" signal of the switch 8' appears at the other input terminal of the AND gate circuit 56, and the "1" output signal of the register 50 appears at the other input terminal of the AND gate circuit 56. Under this condition, the output pulse of the oscillator 58 appears at the output terminal of the AND gate circuit 56, and the pulse is supplied to the X pulse motors 20 and 22, causing the X cursors 24 and 26 to move in the +X axis direction at a speed FB. do. When the switch 8' is turned OFF, the gate of the AND gate circuit 56 is cut off and the X pulse motors 20 and 22 are stopped, and a pulse 42 is output from the differentiating circuit 40, and this pulse 42 is sent to the output side of the AND gate circuit 54. appears as an X fixed origin distance movement command. With this command, a predetermined number of +X-axis direction component pulses are input to the X pulse motors 20 and 22, and the X cursors 24 and 26 are moved to the pen 3.
6 moves until it reaches the X fixed origin position. In a similar manner, the -Y stroke end limit switch 16' (not shown) corresponding to the switch 16 controls the Y cursor 34 to return to its origin, and the pen 36 moves to the fixed origin A set on the table 2 (see Fig. 1). (see). When the fixed origin return operation is completed, the controller resets the register 50. The above operation will be explained based on the flowchart shown in FIG. Check whether or not is in the -X stroke end area, and if it is OFF, that is, outside the area, supply pulses in the -X axis direction component to the X pulse motors 20 and 22 until switch 8' turns ON, and move the X cursor. 24 and 26 are driven in the -X axis direction at a speed of FT. Note that if the X cursor is within the above area, it will not move in the -X axis direction. −
X stroke end limit switch 8' is ON
Then, the controller controls the X pulse motor 2
The supply of pulses in the -X axis direction component to 0 and 22 is stopped. Next, apply +X to the X pulse motors 20 and 22.
Give an axial component pulse and move the X cursor 24.2
6 in the +X-axis direction at the speed of FB. At this time, the controller determines whether the -X stroke end limit switch 8' is ON or OFF, and when it is OFF, stops supplying pulses to the X pulse motors 20 and 22.

Next, a predetermined number of +
Supplying pulses in the X-axis direction, X cursor 24.2
6 to the X fixed origin distance, and move the X cursor 2
End the origin return control of 4.26. If you return the Y cursor 34 to the Y fixed origin using the same procedure,
The pen 36 can be returned to the fixed origin A. Incidentally, the fixed origin may be set at the position of the pen 36 at the time when the -X stroke end limit switch 8' and the -Y stroke end limit switch 16' are changed from ON to OFF. Note that the -X stroke end limit switch 8' and -Y stroke end limit switch 16' used in this embodiment may be of any type as long as they can detect the positions of the cursors 24 and 34, and the pulse detector for position detection may be used. This includes nerators and others.

Since the present invention is constructed as described above, by using the -X stroke end limit switch and the -Y stroke end limit switch,
The XY deceleration command switch and the XY origin stop command switch can be deleted, and the -X stroke end limit switch and -Y stroke end limit switch can be placed outside the effective drawing range, reducing their mechanical and electrical life. I have nothing to do. Moreover, there are effects such as being able to return the pen to the origin no matter where the XY cursor is located.

[Brief explanation of the drawing]

FIG. 1 is an explanatory plan view of the prior art, FIG. 2 is an explanatory diagram of the same operation, and FIG. 3 is an explanatory circuit diagram of the method of the present invention.
4 is an explanatory diagram of the same operation, FIG. 5 is an explanatory diagram of the same operation, and FIG. 6 is a flowchart of the same. 2...Table, 4...X deceleration command switch, 6...
X origin stop command switch, 8'...-X stroke end limit switch, 10...Y rail, 12
...Y deceleration command switch, 14...y origin stop command switch, 16...-Y stroke end limit switch, 18...pen head, 20, 22...x pulse motor, 24, 26...X cursor, 28, 30
...X rail, 32...Y pulse motor, 34...Y cursor, 36...pen, 40...differential circuit, 42...pulse, 44...inverting amplifier, 48...line, 50...
Register, 52, 54, 56...AND gate circuit, 58...Pulse generator.

Claims (1)

[Claims] 1 a table 2, hung on the table 2,
A Y rail 10 that is movable in the X-axis direction relative to the table 2; a Y cursor 34 that is attached to the Y rail 10 so as to be movable in the Y-axis direction along the Y rail 10; It consists of an attached pen head 18, and the positional relationship between the table 2 and the Y rail 10 and the Y rail 10 are controlled by a controller.
In a fixed origin return method for an automatic drafting machine in which a predetermined pattern is automatically drawn on the table 2 by controlling the movement of the cursor 34, the Y rail 10 is outside the drawing range in the -X axis direction with respect to the table 2. A -X stroke end limit switch 8' for detecting the position of the Y rail 10 is disposed on the movement path of the Y cursor 34, which detects the position of the Y rail 10. When returning the pen head 18 to the fixed origin, first, the -X stroke end limit switch 8' and the -Y stroke end limit switch 16' are turned on. The Y rail 10 is driven at the maximum speed in the -X axis direction relative to the table 2, and the Y cursor 34 is driven at the maximum speed along the Y rail 10 in the -Y axis direction until . , detecting the positions of the Y rail 10 and the Y cursor 34 and detecting the -X
When the stroke end limit switch 8' and the -stroke end limit switch 16' are turned on, driving of the Y rail 10 and the Y cursor 34 in the -X-axis and -Y-axis directions at the maximum speed is stopped, and then the Move the Y rail 10 and Y cursor 34 to the -X stroke end limit switch 8'.
and -Y stroke end limit switch 1
6' is turned OFF, the motor is driven in the +X and Y axis directions at a speed that allows it to stop without error in response to the stop command from the controller, and the -X stroke end limit switch 8' and -Y stroke end limit switch 16' are turned OFF. When the pen head 1 in this state is stopped, the movement of the Y rail 10 relative to the table 2 in the +X axis direction and the movement of the Y cursor 34 in the +Y axis direction are stopped.
8. A method for returning to a fixed origin, characterized in that the position of the pen in No. 8 or a position moved a predetermined distance from the position is set as the fixed origin of the pen on the table.