KR880001165B1 - Origin control circuit in numerical programming control device - Google Patents

Abstract

The detection circuit can move rapidly from an arbitray position of X-Y table in initial operation to the original position of X-Y table. The synchronizer (2) is composed of D-type flip flop and the encoder of motor generates the output pulse in proportion to the number of motor rotation. The logic circuit (4) is composed of several logic gates and D-type flip flops. The counter loading member (6) loads the arbitrary values to the counter (3) in order to accomplish the high-speed detection of the original position of X-Y table.

Description

High Speed Home Detection Circuit of Numerical Control Device

1 is a block diagram of the present invention.

2 is a circuit diagram of the present invention.

3 is a waveform diagram according to the present invention.

Figure 4 is a view for explaining the home positioning method according to the present invention.

5 is a flowchart art according to the present invention.

* Explanation of symbols for main parts of the drawings

1: central processing unit 2: synchronization unit

3: counter section 4: logic circuit section

5: buffer part 6: counter loading part

7: decoder

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an origin detection circuit of a numerical control device that is a control device of an XY table using a microprocessor. In particular, the present invention relates to a high speed home detection circuit capable of returning an XY table located at an initial position to a home position at high speed. It is about.

In recent years, as automation devices are getting faster and more precise, control technologies using microprocessors designed to be able to vary the software and to process data at high speed have begun to develop. It is the high speed and precision control of the motor, which has been widely applied to the control of automation equipment, automatic part inserters, robots, and the like. In the case of controlling the motor applied to such a device, when controlling the motor which is the driving source of the X-Y table in the numerical control device, the reference origin must be found at the beginning of operation to calculate the moving position of the X-Y table. Therefore, various methods have been proposed as a method for finding the origin, and one of them is setting the origin at a low speed from the beginning so as not to pass the origin while searching for the origin due to the rotational inertia of the motor driven to find the origin. There was a circuit designed to do this, which was inconvenient that the initial operation of the device had to wait long enough for the XY table to find the origin. Another method is to allow the XY table to find the origin at high speed, but this is achieved by first driving the motor at high speed to approach the table near the origin and then near the origin by sensing the sensor installed near the origin. At least two sensors (near the origin and the sensor installed at the origin) are required because the XY table is slowly moved from the origin to the origin. Therefore, the high speed home detection circuit has a problem that the detection speed is high but the cost is increased.

The present invention is to solve the above problems, in order to be able to find the origin of the XY table at high speed while using a single sensor, the drive motor that is the driving source of the XY table when the initial power is applied to the numerical control device, that is X -The table drive motor and the Y table drive motor are rotated at high speed in the reverse direction (home direction) to move the XY table at high speed.When the XY table reaches the origin, the sensor loads a constant value to the counter by sensing. After decelerating the drive motor and reducing the number of loads loaded on the counter, when the counter count reaches "0", the drive motor rotated in the reverse direction is stopped and rotated in the forward direction. By moving it, when the XY table is first rotated at high speed and then moved back to the origin It is an object of the present invention to provide a high speed home detection circuit of a numerical control device which can move an X-Y table within a short time when viewed as a whole because the distance that is rotated at a low speed but is moved at a low speed is very short.

Hereinafter, the configuration, operation, and effects of the present invention will be described in detail.

The present invention provides a central processing unit (1), a synchronizing unit (2) for synchronizing the encoder output of the motor with a reference clock of the central processing unit (1), and a counter unit (3) in response to the output of the synchronizing unit (2). The rotational displacement of the motor is counted by using the up and down direction control signal of the motor, the logic direction detection signal and the lowest unit information signal of the motor, and the up and down direction control signal outputted from the logic circuit unit 4. The counter section 3, the buffer BF ₄ (BF ₅ ) which transmits the output of the counter section 3 to the central processing unit 1, the rotation direction information signal of the motor, the lowest unit information signal, and the origin A buffer unit 5 consisting of a buffer BF ₁ for transmitting a detection signal to the central processing unit ₁ , and a counter loading unit for loading the output of the central processing unit 1 into the counter unit 3. (6), selecting the buffer unit 5 and the counter loading unit 6 in accordance with the output of the central processing unit 1 A decoder configured to generate a chip enable sensation (CE) to select the buffer unit 5 and the counter loading unit 6 according to the output of the counter loading unit 6 and the central processing unit 1 It is composed of 7).

1 shows a block diagram of the present invention. The synchronizing unit 2 is composed of a D flip-flop. The synchronizing unit 2 receives an output signal of a motor encoder that generates a pulse proportional to the rotation by the rotation of the motor, synchronizes it with the CPU reference clock which is a system clock, and then synchronizes the signal with the logic circuit unit. Output to (4).

The logic circuit part 4 includes some gate elements such as AND gate AND ₁ (AND ₂ ), NOR gate NOR ₁ , and NAND gate ND ₁ (ND ₂ ), and D flip-flop FF ₅ (FF). ₆ ), using the motor encoder signal synchronized with the system reference clock to generate an upward control signal UP and a downward control signal DW which increase or decrease the coefficient of the up-down counter, which will be described later. . The up-down direction control signal UP (DW) is to increase or decrease the counter according to the rotational displacement of the motor so that the central processing unit 1 detects information about the motor. In addition, the logic circuit unit 4 also generates the lowest unit information signal and the rotation direction information signal of the motor and outputs them to the central processing unit 1 through the buffer unit 5. The counter unit 3 is loaded according to the up-down direction control signal UP (DW) of the motor output from the logic circuit unit 4 to increase or decrease the coefficient to detect the rotational displacement of the motor. The rotational displacement information of the motor is output to the central processing unit 1 through the butter part 5.

The counter loading section 6 is for loading the counter section 3 with any value necessary for the rotational displacement of the motor in order to perform the high speed home position detection of the X-Y table.

The decoder 7 generates an enable signal for making the corresponding buffer in the buffer unit 5 operable according to the output of the central processing unit 1.

The present invention performing the above operation will be described based on the detailed circuit diagram shown in FIG. 2 and the time chart of FIG.

Since the driving method of the drive motor for the X-direction table and the drive motor for the Y-direction table is the same, only one case will be described below in order to avoid duplicate explanation. The sign of the waveform shown in FIG. 3 and the sign of each element shown in FIG. 2 correspond to the output signals of the corresponding elements. The A phase and B phase signals output from the encoder of the motor (not shown in the drawing) are input to the data input terminals D ₁ and D ₂ of the flip-flop FF ₁₂ , respectively. An AND gate AND ₁ and AND ₂ in the logic circuit unit 4 are delayed by one or two clocks by the flip-flop FF ₁₂ (FF ₃₄ ) in synchronization with the clock signal CLK, which is a reference clock. It is input to each flop FF ₆ . The output of the AND gate AND ₁ (AND ₂ ) is input as a clock signal of the D-type trigger flip flop FF ₅ via the NOA gate NOR ₁ . Thus, the signal output from the clip flop FF ₅ and the output signal of the AND gate AND ₁ and AND ₂ are NAND-operated by the NAND gate ND ₁ and ND ₂ , respectively. ) And a downward control signal DW. In addition, the output signal output from the output terminal Q ₅ of the flip-flop FF ₅ is the lowest unit information signal, for example, used as a signal indicating the information of the second decimal place of the displacement of the XY table. In addition, the motor encoder signals A and B are used as the motor rotation direction information by the flip-flop FF ₆ in synchronization with the reference clock CLK, which is transmitted to the central processing unit 1 according to the enable state of the buffer BF ₁ . do.

On the other hand, the up-down direction control signal UP (DW) output from the NAND gate ND ₁ (ND ₂ ) of the logic circuit section 4 is input to each counter in the counter section 3 to increase or decrease the coefficient of the counter. The motor displacement, that is, the displacement of the XY table, is counted. The output signal of the counter 3 there is applied to the buffer (BF ₄₎ (BF ₅₎ in the buffer portion 5, the buffer (BF ₄₎ (BF ₅₎ is the address signal of the central processing unit (1) When the chip of the decoder 7 generated in accordance with the operation becomes enabled by the enable signal CE, the output of the counter unit 3 is loaded on the data bus and inputted to the central processing unit 1. Therefore, when the central processing unit 1 wants to know the position of the motor, it is possible to read the count information of the counter section 3 by selecting the buffers BF ₄ (BF ₅ ) by software by the system program. The rotational displacement of can be detected.

The present invention operating in a circuit as described above will be described in detail based on the operational state of FIG. 4 and the flowchart of FIG.

When power is first supplied to the numerical control device, the central processing unit 1 determines whether to return the XY table to the origin, and then first returns the XY table at an arbitrary position to the origin. By outputting the high-speed reverse rotation signal from the central processing unit 1 to the drive motor, the XY tables located at arbitrary positions are driven at high speed ("ga" section in FIG. 4) toward the origin sensors, respectively. During this period, the central processing unit 1 sends the chip enable signal to the buffer BF ₁ through the decoder 7 and detects the variation of the home detection signal. Then, when the home detection signal drops from high level to low level, for example, when the bracket of the table traveling at high speed blocks the light of the optical sensor, the home detection sensor, the signal is connected to the data bus connected to the buffer BF ₁ . By being input to the central processing unit 1 through the central processing unit 1 will detect that the table is passing through the origin. Accordingly, the central processing unit 1 loads the signal "XX" which is a value set in advance arbitrarily by using the respective counters in the counter section 3 through the buffers BF ₂ (BF ₃ ) by the built-in software.

Since the load value of the counter part 3 becomes an arbitrary value by the table which traveled at high speed from the arbitrary position to the origin, the initial value of the counter part 3 is instantaneous when the table detects the origin. This is to set the value. When the central processing unit 1 detects the moment when the table passes the origin, the table is decelerated and traveled through the orbit shown in FIG. 4. At this time, the central processing unit 1 sets the target position to "XX-YY" to decelerate the table. Here, YY means the driving distance until stopping the table while driving at high speed. In the deceleration section of the track B, the central processing unit 1 continuously decelerates when comparing the positions of the deceleration table and the current table by the system software, and then buffers BF ₄ (BF ₅ ) loaded with the values of the counter section 3. If the value of is "XX-YY", stop the table ("D" position).

Thereafter, the central processing unit 1 outputs a signal for rotating the driving motor back to move the table at a low speed to the origin (section C). At this time, the reason for moving the table at low speed when moving the table to the origin is that the table stops exactly at the origin regardless of the inertia of the table, even if it receives a stop command from the central processing unit (1) when the origin sensor is detected. It means the speed as possible. That is, if the bracket of the table cuts off the light of the home detection sensor while moving the section C, the table is stopped at the moment when the home detection signal detects that the home detection signal falls to the low level through the buffer BF ₁ . At the same time, " OO " is loaded into the counter section ₃ via the buffers BF ₂ and BF ₃ .

In this way, the origin detection operation for returning each table to the origin is completed.

As described above, the present invention enables the XY table located at an arbitrary position to be moved to high speed accurately at the beginning of operation by using only one origin sensor in the numerical control device, thereby reducing the cost when constructing a circuit for the origin detection. In addition to the advantages, work efficiency is improved by shortening the working time.

Claims (1)

The central processing unit 1, the synchronizing unit 2 which synchronizes the encoder output of the motor with the reference clock of the central processing unit 1, and the upper and lower sides of the counter unit 3 in response to the output of the synchronizing unit 2; A logic circuit section 4 for outputting a direction control signal UP (DW), a rotation direction detection signal of the motor and a lowest unit information signal, and a vertical control signal UP (DW) output from the logic circuit section 4 (DW) The counter unit 3, which is configured to count the rotational displacement of the motor by using the motor, and the buffer BF ₄ (BF ₅ ) which is configured to transmit the output of the counter unit 3 to the central processing unit 1, A buffer unit 5 consisting of a buffer BF ₁ for transmitting the rotation direction information signal, the lowest unit information signal, and the origin detection signal to the central processing unit 1, and counters the output of the central processing unit 1 (6) a counter loading section (6), to be loaded in the buffer unit (5) or the counter loading in accordance with the output of the central processing unit (1) 6, high-speed point detection of numerical control device comprising a time to the decoder 7 to the needle generates an enable signal (CE) to select.

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