JP5296419B2 - How to change the ladder program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate machine control using a programmable controller without adjusting the physical position of a sensor or the like, while allowing adjustment of the timing of sensor detection signals or the like. <P>SOLUTION: A timing chart whose horizontal axis represents a lapse of time and whose vertical axis indicates on/off of an input contact or an output contact displayed by a ladder symbol on a ladder program, is displayed on the display screen of a programming tool 10. A signal waveform indicating the on/off of the input contact is adjusted over the timing chart to modify the ladder program related to the input contact. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a ladder program changing method, a display screen, a programming tool, and a control system.

  A ladder program is one method for describing a program that defines a control sequence in a ladder diagram format. In the ladder diagram, the circuit diagram is drawn in the form of a ladder, and the two vertical busbars at both ends represent the power symbolically, and the input and output contacts are indicated by ladder symbols on a parallel line connecting horizontally between them. . In the ladder diagram, the contents of the processing are displayed as the relationship between these contacts.

  Then, the user creates a ladder program with a programming tool such as a personal computer, and transfers and loads the created ladder program to the programmable controller. In the programmable controller loaded with the ladder program in this way, connect the input / output device to the actual input / output contact (actual machine input / output contact) corresponding to the input / output contact indicated by the ladder symbol on the ladder diagram. Through the actual input / output contact, for example, the position of the bottle transported on the belt conveyor is detected by a sensor, and from the sensor detection signal, the actuator is driven to control a series of machine operations such as liquid injection, cap attachment, and cap tightening. It is supposed to be.

  In such a series of machine operations, the motor speed that drives the belt conveyor, the bottle detection by the sensor, the liquid injection into the bottle by the actuator, the bottle cap removal, and the bottle cap tightening timing are controlled according to the process order. It is necessary to be done.

  Therefore, for example, when the physical attachment position of the sensor is deviated from the normal position, the input timing of the sensor detection signal input to the actual machine input contact is deviated, so the physical attachment position of the sensor is adjusted. Things have been done. This is similarly adjusted in the belt conveyor drive motor, actuator, and the like.

However, the mounting position of this sensor often cannot be adjusted easily due to circumstances such as the situation in the factory and the positional relationship of the control panel, and this mounting adjustment takes a lot of time and labor. May be required. In addition, the following patent document 1 can be mentioned as a prior document of such a programmable controller.
JP-A-10-161710

  Therefore, the problem to be solved by the present invention is to enable machine control by a programmable controller without the need to adjust the physical position even if the physical mounting position of a device such as a sensor is shifted. That is.

The method of changing the ladder program according to claim 1 of the present invention is based on the screen display, with the passage of time on the horizontal axis and the ON / OFF change of the input contact and output contact displayed on the ladder program as ladder signals on the vertical axis. Is displayed, and the signal waveform indicating the ON / OFF change of the input contact on the displayed timing chart is adjusted by dragging and dropping the signal waveform portion to be adjusted according to the waveform adjustment width. Thus , the ladder program related to the input contact can be changed.

  In the present invention, the ladder program related to the input contact can be changed by adjusting the signal waveform indicating the ON / OFF change of the input contact on the timing chart. For example, the sensor connected to the input contact Even if the mounting position of a device such as the above is deviated, the machine can be controlled by the programmable controller without the need to adjust the physical position.

  The display screen according to claim 2 of the present invention is characterized in that a timing chart used in the method according to claim 1 can be displayed. For example, by providing this display screen in a programmable controller, the user may operate the timing chart in the programmable controller to adjust the waveform of the input signal to the input contact. Further, the display screen may be installed in a portable device, the programmable controller and the portable device may be connected, and the ladder program of the programmable controller may be changed by the portable device.

The programming tool according to claim 3 of the present invention calls a timing chart display window on the display screen, and the timing chart display window displays time on the horizontal axis and ladder symbols on the ladder program on the vertical axis. Display the timing chart showing the ON / OFF change of the input contact and output contact, and display the signal waveform indicating the ON / OFF change of the input contact on the displayed timing chart with the signal waveform part you want to adjust to the waveform adjustment width Accordingly, the ladder program related to the input contact can be changed by dragging and dropping .

The control system according to claim 4 of the present invention connects the programming tool described above to the programmable controller, and displays the input timing of the signal to the actual machine contact of the programmable controller in the timing chart on the timing chart display window of the programming tool. Then, the signal waveform displayed on the timing chart by user operation is adjusted by dragging and dropping the signal waveform part you want to adjust according to the waveform adjustment width, and the ladder program related to the adjustment is changed, and the change The ladder program is loaded into the programmable controller.

  According to the present invention, even if the mounting position of a device such as a sensor is shifted, it is not necessary to adjust the physical position, and by adjusting the waveform of the input signal to the input contact in the timing chart displayed on the display screen. The sequence control can be adjusted.

  Hereinafter, a ladder program changing method, a display screen, a programming tool, and a control system according to embodiments of the present invention will be described with reference to the accompanying drawings.

  Referring to FIG. 1, a control system according to an embodiment includes a programming tool 10 that creates and transfers a ladder program, a programmable controller (PLC) 12 that performs control according to the ladder program transferred from the programming tool 10, and a control 1. A rotary encoder 14 that inputs a predetermined impulse signal to the programmable controller 12 during a cycle (one rotation cycle of the rotary encoder 14 described later). Both the programmable controller 12 and the rotary encoder 14 are installed on the control panel 16.

  As an example of production equipment controlled by the programmable controller 12, the control system also includes a belt conveyor 18, a motor 20 that drives the belt conveyor 18 by a drive signal from the programmable controller 12, and a bottle 22 that is transported on the belt conveyor 18. A plurality of first, second, and third sensors 24, 26, and 28 that input the detection signal to the programmable controller 12 and the bottle 22 that is conveyed on the belt conveyor 18 from the programmable controller 12 And a plurality of actuators (not shown) that actuate the liquid injection mechanism 30, the cap removal mechanism 32, and the cap tightening mechanism 34 according to the drive signal. Reference numeral 36 denotes a cap, and 38 denotes liquid injected into the bottle 22.

  When the bottle 22 transported on the belt conveyor 18 is detected by the first sensor 24 at the first transport position, the detection signal is given to the programmable controller 12. In response to this detection signal, the programmable controller 12 outputs a drive signal to an actuator that drives the liquid injection mechanism 30, whereby the liquid 38 is injected into the bottle 22.

  When the bottle 22 is detected by the second sensor 26 at the second transport position, the detection signal is given to the programmable controller 12. In response to this detection signal, the programmable controller 12 outputs a drive signal to an actuator that drives the cap removal mechanism 32, whereby the cap 36 is removed.

  When the bottle 22 is detected by the third sensor 28 at the third transport position, the detection signal is given to the programmable controller 12. In response to this detection signal, the programmable controller 12 outputs a drive signal to an actuator that drives the cap tightening mechanism 34, whereby the cap 36 is tightened to the bottle 22.

  Referring to FIG. 2, programming tool 10 includes a general-purpose personal computer, and performs a timing chart display unit 40, a timing chart storage unit 42, and a timing chart change function as functional units necessary for describing the embodiment. Operation unit 44 such as mouse and keyboard, basic software, and other edited ladder programs and timing charts are called on the window screen, timing charts are generated, changes are made, programmable controllers 12 and a memory 46 for storing various other application programs, a communication interface 48 for communication with the programmable controller 12, and the above-mentioned program for overall control. And a PU50.

  The timing chart display unit 40 has a display screen for displaying a program work screen, a ladder program, and a timing chart as a normal display. This timing chart is displayed on the window screen called by the operation of the operation unit 44 on this display screen. As shown in FIG. 6 and subsequent figures, the timing chart represents the passage of time on the horizontal axis and the ON / OFF changes of the input contacts and output contacts displayed on the ladder program with ladder symbols on the ladder program. The user can adjust the signal waveform indicating the ON / OFF change of the input contact on the timing chart displayed on the display screen using the operation unit 44. A mouse cursor is displayed on the timing chart display screen, and a signal waveform portion to be adjusted in the signal waveform can be adjusted by dragging and dropping according to the waveform adjustment width. The drag and drop operation signal is input to the CPU 50. The CPU 50 changes the signal waveform to the adjustment position in accordance with the drag and drop operation signal, and changes the ladder program in accordance with the adjustment as described later. .

  The timing chart storage unit 42 stores and stores timing chart data to be displayed on the timing chart display unit 40. This timing chart is prepared in accordance with how the user controls the machine. The user can also create a ladder program along this timing chart.

  The memory 46 can store a ladder program created by the user using the programming tool 10. When the signal waveform indicating ON / OFF change of the input contact in the timing chart on the timing chart display screen is adjusted using the operation unit 44, the changed timing chart is stored again in the timing chart storage unit 42. The Further, as described above, the CPU 50 changes the ladder program in accordance with the change of the timing chart.

  The communication interface 48 is an interface used for communication with the programmable controller 12, and can transfer a ladder program to the programmable controller 12 and receive a ladder program from the programmable controller 12.

  As described above, the CPU 50 controls each part in the programming tool 10 in an integrated manner.

  With reference to FIG. 3, the programmable controller 12 includes a ladder program memory 52, a communication interface 54 for communication with the programming tool 10, and devices such as sensors and actuators as functional units necessary for describing the embodiment. And an input / output interface 56 used for input / output of signals to / from the CPU and a CPU 58 for overall control thereof. Illustration of input contacts and output contacts of the programmable controller 12 is omitted.

  The ladder program memory 52 loads the ladder program transferred from the programming tool 10. The communication interface 54 is connected to the communication interface 48 of the programming tool 10 via a communication cable or through a network. Devices such as sensors 24, 26, 28 and actuators (not shown) are connected to the input / output interface 56. Detection signals are input from the sensors 24, 26, 28, etc. via input contacts. A drive signal can be output via the output contact. The CPU 58 performs overall control of each unit described above.

  Next, among the ladder programs, a ladder program for taking out the cap 36 by the second sensor 26 will be described with reference to FIG.

  In the ladder program shown in FIG. 4 (which can also be referred to as a ladder diagram), a ladder diagram is formed by an input contact X30, a timer TM1, an input contact M30, a timer TM2, an input contact M31, a timer TM3, and an output contact Y30 represented by ladder symbols. Has become a program. The second sensor 26 is connected to the input contact X30, and the rotary encoder 14 is connected to the input contacts M30 and M31. Timers TM1-TM3 are on-delay timers. Detailed description of this ladder program is omitted.

  As described above, the steps of liquid injection, cap removal, and cap tightening are performed on the bottle 22 transported on the belt conveyor 18. In the above, for example, as shown in FIG. When the attachment position of the nozzle 26 is shifted from the normal position A to the position B or C, and the bottle detection timing by the second sensor 26 is too early or too late, the cap is taken out or the cap is tightened as the next step. Will cause problems. Therefore, adjustment of the detection timing by the second sensor 26 is necessary. In the embodiment, there is no need to adjust the physical attachment position of the second sensor 26, and the detection timing of the second sensor 26 is set by a user operation on the timing chart displayed on the display screen of the programming tool 10. It can be adjusted.

  Hereinafter, the timing chart will be described with reference to FIGS. 6 to 8 regarding the cap removing process for the bottle 22 transported on the belt conveyor 18 shown in FIG. The timing charts shown in and after FIG. 6 are timing charts displayed on the timing chart display unit 40 of the programming tool 10 of FIG. 6 to 8, the horizontal axis indicates the passage of time, but one rotation of the rotary encoder 14, that is, a rotation angle of 0 to 360 degrees is defined as one cycle. In the embodiment, the cap removal process will be described for the convenience of description, but it is needless to say that the process is not limited to this process. Of course, machine control using the belt conveyor 18 is merely an example. Furthermore, although the belt conveyor 18 is shown linearly, the drum form may be such that the steps are arranged in a drum form and each process is divided at a certain angle from the drum center. The rotary encoder 14 can be applied regardless of whether the process is linear or drum-shaped.

  6A shows the input timing of the sensor detection signal to the first input contact X30, FIG. 6B shows the input timing of the impulse signal of the rotary encoder 14 to the second input contact M30, and FIG. 6C. Is the input timing of the impulse signal of the rotary encoder 14 to the third input contact M31, and FIG. 6D shows the cap removal signal from the output contact Y30.

  When the detection signal in FIG. 6A matches the impulse signal in FIG. 6B, the cap removal signal in FIG. 6D rises to ON and the impulse signal in FIG. 6C is output. The cap removal signal in FIG. 6D falls to OFF. By actuating the actuator of the cap removal mechanism 32 by this cap removal signal, the cap 36 is removed and attached to the bottle 22. In this case, since the sensor 26 is attached to the regular position A in FIG. 5, it is not necessary to change the timing chart by operating the mouse as the operation unit 44 on the timing chart screen.

  However, as indicated by the solid line in FIG. 7A, the sensor 26 is mounted not at the regular position A but at the irregular position B, so the input timing of the sensor detection signal to the first input contact X30 is too early. If the input timing of the impulse signal of the rotary encoder to the second input contact M30 indicated by the solid line in FIG. 7 (b) does not coincide with the input timing, the mouse operation indicates the broken line in FIG. 7 (a). As shown, when the input timing waveform of the sensor detection signal to the first input contact X30 is shifted, the on-delay operation time corresponding to the shifted amount is set in the first timer TM1, thereby the first input contact X30. The sensor detection signal input timing can be matched with the rotary encoder impulse signal input timing to the second input contact M30, as shown in FIG. The cap is taken out signal is output in the normal state, the cap extraction is performed. In this case, the attachment position of the sensor 26 remains at the irregular position B, and the physical position is not changed.

  In addition, as shown by the solid line in FIG. 8A, the sensor 26 is mounted not at the regular position A but at the irregular position C, and therefore the input timing of the sensor detection signal to the first input contact X30 is too late. When the input timing of the impulse signal of the rotary encoder to the second input contact M30 indicated by the solid line in FIG. 8B is not coincident with the timing, it is indicated by the broken line in FIG. As described above, when the input timing waveform of the impulse signal of the rotary encoder to the second input contact M30 is shifted, the on-delay operation time corresponding to the shifted amount is set in the second timer TM2, whereby the first input contact is set. The input timing of the sensor detection signal of X30 and the input timing of the impulse signal of the rotary encoder to the second input contact M30 can be matched, 6 (d) a cap extraction signal is output in the normal state as shown by the cap extraction is performed. In this case, the attachment position of the sensor 26 remains the irregular position C, and its physical position is not changed.

  In this way, if the input timing of the sensor detection signal to the first input contact X30 and the input timing of the impulse signal of the rotary encoder 14 to the second input contact M30 and the third input contact M31 are shifted in the timing chart, the amount of the shift is as follows. The ladder program is changed so that the on-delay time is set in each of the timers TM1, TM2, and TM3.

  The changed ladder program is transferred from the communication interface 48 of the programming tool 10 via the communication interface 54 of the programmable controller 12 and loaded into the ladder program memory 52 of the programmable controller 12.

  As described above, in this embodiment, the programming tool 10 is connected to the programmable controller 12, and the timing chart in which the input timing of the signal to the input contact of the programmable controller 12 is displayed on the timing chart display unit 40 of the programming tool 10. The signal waveform displayed in the timing chart is adjusted by the user operation, the ladder program related to the adjustment is changed, and the changed ladder program is loaded into the programmable controller 12, so that the sensor or the like Even if the device mounting position is shifted, the sequence control can be adjusted without the need to adjust the physical position.

FIG. 1 is a diagram illustrating a configuration of a control system including a personal computer, a programmable controller, and equipment to be controlled. FIG. 2 is a diagram showing a schematic block configuration of the personal computer. FIG. 3 is a diagram showing a schematic block configuration of the programmable controller. FIG. 4 is a diagram showing a ladder diagram format program. FIG. 5 is a diagram showing a part of the equipment of FIG. FIG. 6 is a timing chart corresponding to the ladder program for controlling the equipment of FIG. FIGS. 7A and 7B are timing charts corresponding to FIGS. 6A and 6B. FIGS. 8A and 8B are timing charts corresponding to FIGS. 6A and 6B.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Programming tool 12 Programmable controller 14 Rotary encoder 16 Control board 18 Belt conveyor 20 Motor 22 Bottle 24, 26, 28 Sensor 30, 32, 34 Mechanism 36 Cap

Claims (4)

The screen display, the elapsed time on the horizontal axis, in the ladder program displays a timing chart showing the ON / OFF change of the input contact and output contact are displayed in the ladder signal on the vertical axis, at the displayed timing chart on It is possible to change the ladder program related to the above input contact by adjusting the signal waveform indicating ON / OFF change of the input contact by dragging and dropping the signal waveform portion to be adjusted according to the waveform adjustment width. A method for changing a ladder program characterized by the above.   A display screen capable of displaying a timing chart used in the method according to claim 1. The timing chart display window is called on the display screen, and the timing chart display window indicates the passage of time on the horizontal axis and the vertical axis indicates the ON / OFF change of the input contact and output contact displayed in ladder symbols on the ladder program. Display the chart , adjust the signal waveform indicating the ON / OFF change of the input contact on the displayed timing chart by dragging and dropping the signal waveform part you want to adjust according to the waveform adjustment width, A programming tool that makes it possible to change ladder programs related to input contacts. The programming tool according to claim 3 is connected to the programmable controller, and the input timing of the signal to the actual contact of the programmable controller is displayed on the timing chart on the timing chart display window of the programming tool, and displayed on the timing chart by a user operation. The signal waveform to be adjusted is adjusted by dragging and dropping the signal waveform part to be adjusted according to the waveform adjustment width, the ladder program related to the adjustment is changed, and the changed ladder program is loaded to the programmable controller A control system characterized by that.

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