JP3222968B2 - Process control equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to an apparatus for continuously processing or manufacturing a large number of articles. INDUSTRIAL APPLICABILITY The present invention uses a plurality of automatic control type process control systems connected by one common device (for example, a conveyor device) for factory equipment operated in synchronization with the common device. The present invention relates to a control device in which a control signal is digitized.

[0002]

2. Description of the Related Art A plurality of conveyor apparatuses are arranged, and a large number of guide A apparatuses, guide B apparatuses, guide C apparatuses and the like for processing articles are arranged along each of the plurality of conveyor apparatuses. The goods conveyed by the product gradually become semi-finished products from the material form, and further become products and merge into one conveyor device, and are packed in a form that can be shipped in large quantities and continuously discharged products at the exit of the conveyor device Such factory equipment is widely known. Such factory equipment is devised so that it can be automated with as little human intervention as possible, and various techniques for designing such factory equipment according to the type and nature of the product are known.

[0003] In such factory equipment, it is necessary that all devices be synchronized with one reference operating speed.
The reference operating speed is, for example, the operating speed of the conveyor device, and many processing devices arranged along the conveyor device are set so that products are processed according to the operating speed of the conveyor device. . If some devices perform a large amount of processing beyond this operating speed, semi-finished products that cannot be processed in the next step will accumulate. Also, if some devices perform machining at a speed lower than this operation speed, smooth operations cannot be performed in subsequent steps.

[0004] Further, there is known a technique for changing the reference operating speed. For example, when it is desired to increase the number of products to be manufactured by 10%, instead of increasing the operation time by 10% at a constant operation speed, the operation speed per day is increased by increasing the reference operation speed by 10%. The desired quantity can be manufactured without changing the time.

[0005] In such equipment, many devices and systems that are operated synchronously often have automatic control systems each of which is servo-controlled. In order to synchronize such a large number of devices and systems with one reference operating speed, transmission devices for transmitting electric signals between the devices have been known. An example of a standard for this purpose is that a transmission line is a pair of electric wires, and the pair of electric wires has a length of 4 m.
This is an analog system for transmitting and receiving a DC current that varies in a range from A to 20 mA, which is very widely used.

[0006]

In recent years, microprocessors have been introduced into various processing apparatuses, and it has become convenient for control signals to be digital signals. In particular, in a servo control system provided in each processing apparatus, so-called feedback information that is connected back from the controlled apparatus generally uses digital signals. For this reason, synchronization using digital signals has been considered even in the above-described factory equipment. However, the equipment that involves digital signal processing for this purpose is a rather expensive equipment that employs a microprocessor and software, and has the disadvantage that it tends to be excessive quality equipment.

Further, a system for synchronously operating the entire factory needs to be simple and have high reliability, and it is necessary that the maintenance and inspection be easy for an operator to see. Those relying on the processor and the software loaded into it do not meet this requirement.

[0008] The present invention has been made in such a background, the structure is simple and simple, the equipment is inexpensive, equipment can be easily added or changed, and the maintenance and inspection is performed by an operator. Another object of the present invention is to provide a process control device which is easy to understand and has high reliability.

[0009]

According to the present invention, there is provided an input terminal for inputting operating speed information serving as a reference of a controlled system, and operating control information is transmitted to one device belonging to the controlled system in accordance with the operating speed information. In the process control device having an output terminal for outputting, the operating speed information is a reference pulse train arriving at a frequency proportional to the operating speed, and a part of the reference pulse train corresponds to an operating speed ratio with respect to the reference pulse train. Command pulse train output means for outputting a pulse train serving as operation control information by dropping at a ratio, wherein the command pulse train output means sets a predetermined acceleration or deceleration step when accelerating or decelerating the operation speed. Unit reference pulse
Output a predetermined number of pulses according to the gear ratio
Speed stages with different gear ratios
Combine the gears so that the floor pulse intervals are averaged
And means for outputting the pulse train .

[0010] A gate circuit provided between the input terminal and the output terminal, and bit information indicating the lack or passage of the reference pulse are accumulated, and the bit information is sequentially transmitted using the signal of the input terminal as a clock signal. A shift register for giving a control input to the gate circuit; and an arithmetic circuit for sequentially inputting the bit information into the shift register, wherein the arithmetic circuit stores a program control circuit, and a program and a control pattern of the program control circuit. The program control circuit has an automatic mode, a manual mode,
It is desirable to include an origin matching mode and a simulation mode.

The output terminal of such a process control device is connected to a drive circuit, and the output of the drive circuit is supplied as a drive current to a motor of one of the devices belonging to the controlled system, and is driven by the motor. A process control system in which the position signal of the device to be controlled is connected back to the drive circuit, and a plurality of the process control systems are provided. )
This common device may be provided as a factory facility with a means for generating a pulse train commonly supplied to a plurality of process control devices as the reference pulse.

[0012]

At one place in the equipment, for example, an encoder interlocked with a main motor that applies a rotational force to a conveyor generates a reference pulse train having a frequency proportional to a reference operation speed. The frequency of this reference pulse is, for example, 10 to 20 kHz.
Range. This reference pulse train is branched and connected to the input terminal of each process control device.

[0013] Each process control device controls whether to pass or block the reference pulse train and sends it to an output terminal. During the period when the reference pulse train is completely passed, the controlled device is operated at the maximum speed. During a period in which the reference pulse train is completely blocked, the controlled device is stopped. When passing every other reference pulse train, the controlled device is operating at half the maximum speed. As the number of missing reference pulse trains is gradually increased, the controlled device decelerates. As the loss of the reference pulse train is gradually reduced, the operation of the controlled device is accelerated. If reverse rotation is required for the operation of the controlled device, provide another output terminal in addition to the above output terminal, and add a polarity signal (for example, 1 for plus direction and 0 for minus direction). Thus, the configuration can be simplified.

Such control is extremely simple and the circuit scale can be reduced, so that the device can be manufactured at low cost and the reliability can be improved. Also, by monitoring the signals at the input and output terminals of the process control device with an oscilloscope or frequency counter,
The person performing the maintenance work can visually inspect. Therefore, there is a sense of security that is easy to understand compared to the one that involves software control. If there is a failure, it can be dealt with immediately and the failure can be prevented. By branching the signal of the reference pulse train and connecting it to the input terminal, it is possible to easily add equipment.

By changing the frequency of the reference pulse train, the operating speeds of all the devices can be changed synchronously. For example, by changing the rotation speed of the main motor, the operation speeds of all the devices are changed simultaneously in synchronization.

[0016]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a main part of a process control device according to an embodiment of the present invention.

The process control apparatus according to the embodiment of the present invention includes an input terminal 1 for inputting operating speed information which is a reference of a controlled system,
An output terminal 2 for outputting operation control information to one device belonging to the controlled system in accordance with the operation speed information, wherein the operation speed information is a reference pulse train arriving at a frequency proportional to the operation speed; The pulse train is composed of a pulse train in which some pulses are missing. further,
A gate circuit 3a provided between the input terminal 1 and the output terminal 2 stores bit information indicating the lack or passage of the reference pulse, and sequentially uses the signal at the input terminal 1 as a clock signal to sequentially gate the bit information. A shift register 3b for giving a control input of 3a; a pulse generating circuit 3 including a buffer circuit 3c; and an arithmetic circuit 5 for sequentially inputting the bit information to the shift register 3b.
A program control circuit 5a;
and a memory circuit 5b for storing a program and a control pattern of the program a. The program control circuit 5a includes an automatic mode, a manual mode, an origin matching mode, and a simulation mode as its operation modes.

FIG. 2 is a diagram showing an example of a process control system provided with a process control device according to the present invention.

In this embodiment, a main conveyor 20 is used.
1 shows an example in which a guide A device 21, a guide B device 22, and a guide C device 23 are arranged, and each device is provided with a process control device 10 of the present invention.
The output terminal 2 is connected to the drive circuit 11, and the output of the drive circuit 11 is supplied as a drive current to the respective motors 12 of the guide A device 21, the guide B device 22, and the guide C device 23 belonging to the controlled system. . The position signals of the guide A device 21, the guide B device 22, and the guide C device 23 driven by the motor 12 are fetched from the servo encoder 13, and the respective drive circuits 1
1 is connected back.

A plurality of such process control systems are provided, and the plurality of process control systems are provided with a common device (conveyor) commonly associated with the plurality of process control systems. Factory equipment can be provided with means for generating the supplied pulse train.

Next, the operation of the embodiment of the present invention configured as described above will be described with reference to FIGS.

First, the operation of the servo motor drive system according to the embodiment of the present invention will be described.

The main drive motor 20 of the conveyor device 20
When a is started, the main speed detection encoder 20b sends out the reference pulse Pm (10 to 20 KHz). The pulse generating circuit 3 of the process control device 10 receiving the reference pulse Pm checks the data of the pulse pattern PP sent from the program control circuit 5a and outputs only necessary pulses to the drive circuit 11 as command pulses Ps. The drive circuit 11 guides the guide A in accordance with the command pulse Ps.
Device 21, guide B device 22, and guide C device 23
Are driven. The driving state is detected by the servo encoder 13 and fed back to the driving circuit 11 so that the motor 12 of each device is driven by the main driving motor 20a.
Is controlled to follow.

The command pulse Ps for speed following by the program control circuit 5a of the process control device 10
The calculation algorithm of a will be described. FIG. 3 is a diagram illustrating an example of a pulse pattern calculated by a calculation algorithm.

The speed following means that the command pulse Ps is output at a certain ratio with respect to the reference pulse Pm.
2 is rotated at a certain ratio, for example, assuming that Pm: Ps = 50: 31, the command pulse Ps at this time is as uniform as possible every 50 pulses of the reference pulse Pm.
A pattern must be formed such that 31 pulses are input to one.

First, a reference unit α is obtained by the following equation.

Pm ÷ Ps ≒ α This α is multiplied by an integer up to n = 1, 2,... Ps, and the result is set to β1, β2. Γ1 to γ obtained by rounding off the first decimal place of each value of β1 to βS
S is the pulse number to be extracted from the reference pulse Pm, and is Psa.

[0028] To illustrate this, Becomes

That is, as shown in FIG. 3, by extracting the second, third, fifth,..., 50th pulses of the reference pulse Pm, a uniform 31-pulse command pulse Psa can be obtained. 3 is a reference pulse Pm.
The lower row shows a command pulse Psa for speed following calculated by the algorithm and extracted from the reference pulse Pm.
It is. By repeating this pattern, the motor 12
Is a constant speed ratio (31/5 of the reference speed in the above example)
0).

Next, the calculation algorithm of the command pulse Psb for the acceleration / deceleration operation required for the pattern operation in the program control circuit 5a of the process control device 10 will be described.

The algorithm for calculating the command pulse Psb at the time of deceleration requires that the deceleration be performed as smoothly as possible as a condition for deceleration. For this purpose, the shift stages must be distributed as evenly as possible. Here, the reference pulse used for the deceleration operation is M pulses, the number of shift steps is 5, the reference pulse is a multiple of 10 assuming that the pattern is formed in units of 10 pulses, and the reference pulse number M is divided by 10. The value m is set to 5
To obtain the reference unit α. This α is multiplied by an integer up to 1, 2,... 5, and the resulting output pattern in the deceleration stage is obtained from the values of γ1, γ2,. To determine. The five-step basic deceleration pattern for 10 reference pulses is 9,
7, 5, 3, and 1 pulses are used, and how many times these five patterns are output is calculated. The content of the calculation is shown in the following equation and [Table 1].

M ÷ 5 = α (reference unit) α × 1 = β1 ··· γ1 α × 2 = β2 ··· γ2 α × 5 = β5 ··· γ5

[0033]

[Table 1] The "number of outputs" in Table 1 is a number indicating how many times the number of output pulses for 10 pulses is repeated. For example, the uppermost row shows that 9 pulses are repeated γ1 times.

As a practical example, the reference pulse m for the deceleration operation is set to 10
When the number of pulses is 0, the result is as shown in the following equation and [Table 2].

10 ÷ 5 = 2.0 (reference unit) 2.0 × 1 = 2.0... 2.0 2.0 × 2 = 4.0... 4.0 2.0 × 5 = 10.0 ... 10.0

[0036]

[Table 2] That is, when the number m of deceleration reference pulses is 100 pulses, 1
9, 9, 7, 7, 5, 5, 3, 3, 1,
By extracting one pulse, a relatively uniform deceleration command pulse Psb can be obtained. FIG. 4 shows a pulse output pattern of this example. The upper pulse in FIG. 4 is the reference pulse Pm, and the lower pulse is the command pulse Psb for deceleration operation required for the pattern operation calculated by the above algorithm and extracted from the reference pulse Pm. The acceleration control is performed as a reverse operation in the case of such a deceleration.

Next, an algorithm for transferring the command pulse pattern Ps data calculated by the program control circuit 5a to the pulse generation circuit 3 will be described with reference to FIG.

In the program control circuit 5a, the command pulse Ps calculated by the algorithm is stored in the pattern storage registers R1 to Rn in units of 10 pulses. On the other hand, in the pulse generating circuit 3, the data register R serving as a window between the working register Rx and the program control circuit 5a is used.
y is ready. The work register Rx outputs “1” as the command pulse Ps when the set pulse pattern (Ps1) is “1” when the reference pulse Pm is “1”. When this control is completed 10 times (that is, the reference pulse Pm is 10 pulses), the next pattern (Ps2) is received from the data register Ry. Since the next pulse pattern does not exist in the data register Ry by this operation, the pattern data (Ps3) is obtained from the pattern storage register R3 of the program control circuit 5a.
Receive. That is, the data transfer between the pulse generation circuit 3 and the program control circuit 5a is executed as an interrupt process every 10 pulses of the reference pulse Pm, and the load on the pulse generation circuit 3 can be reduced by this method.

Next, the operation mode of the program control circuit 5a will be described. 6 is a flowchart showing an operation flow in the automatic mode, FIG. 7 is a flowchart showing an operation flow in the manual mode, FIG. 8 is a flowchart showing an operation flow in the origin adjustment mode, and FIG. 9 is a flowchart showing an operation flow in the simulation mode. It is a flowchart shown.

In the automatic mode, as shown in FIG. 6, after the automatic preprocessing is performed, it is determined whether or not the origin of the controlled device is set correctly. If the origin is not set correctly, This is notified and the control operation ends. If the origin is set correctly, it is determined whether the operation is to be performed or the operation is to be stopped, and the operation processing or the stop processing is performed.

Next, it is determined whether or not the step is set to "0". When the step is set to "0", the process of setting the step "0" is performed. When the step is not set, the step number is set. Is performed, and the step update process is performed. Subsequently, it is determined whether or not to drive in the automatic mode, and when driving in the automatic mode is continued,
Returning to the "run / stop determination process", the same processing operation is repeated. If the operation is not performed in the automatic mode, a stop process is performed and the process ends.

The manual mode is a mode for driving the vehicle manually. In this manual mode, as shown in FIG. 7, after the manual preprocessing and the input / output processing are performed, it is determined whether the operation is the operation or the stop. If the operation is not performed, the stop processing is performed. When performing the operation, it is determined whether the operation is the normal operation or the reverse operation, and the normal operation or the reverse operation is performed according to the judgment, and either operation is executed.

After the above-described stop processing or operation processing is performed, it is determined whether or not the manual mode is to be continued. If the manual mode is to be continued, the process returns to the "input / output processing" and the same processing is repeated. If the manual mode is not to be continued, stop processing is performed, and then manual post-processing is performed and the processing ends.

The origin matching mode is a mode for correctly setting the initial position of the controlled system, and is executed before starting the automatic mode.

In this origin matching mode, as shown in FIG. 8, after the origin matching initialization processing and the input / output processing are performed, it is determined whether or not the operation is to be performed. It is determined whether the mode is set to the origin matching mode. If the mode is set to the origin mode, the process returns to the "input / output processing".

When operating in the origin matching mode,
It is determined whether the operation is the normal rotation operation or the reverse rotation operation. In the case of the normal rotation operation, the normal rotation process and the input / output process are performed, and it is determined whether or not there is a stop or origin adjustment mode command.
If there is a command of the home position adjustment mode, it is determined again whether the operation is the normal rotation operation or the reverse rotation operation. In the case of the reverse rotation operation, after the stop processing is performed, the reverse rotation processing is performed, and then the input / output processing is performed. It is determined again whether there is a stop or origin adjustment mode command.

On the other hand, if it is determined in the first "forward rotation / reverse rotation determination processing" that the operation is the reverse rotation, the process proceeds to the above-described reverse rotation processing. If it is determined that the engine is running forward in the second "forward / reverse determination process", the process proceeds to the second "input / output process". Further, when it is determined that there is a stop command in the first “stop / mode command determination process”, a stop process is performed,
Subsequently, it is determined whether or not the mode is still set to the origin matching mode. When the mode is set to the origin matching mode, the process returns to the first "input / output process". When the mode is not set to the origin matching mode, a stop process is performed.

When it is determined in the second "stop / mode command determination process" that there is a command for the origin adjustment mode,
It is determined whether the operation is the normal rotation operation or the reverse rotation operation. If the operation is determined to be the reverse rotation operation, the process returns to the third “input / output processing”. Also,
When it is determined that the operation is the normal rotation operation, the normal rotation processing and the input / output processing are performed after the stop processing, and it is determined again whether there is a stop or origin adjustment mode command. Here, if there is a command for the origin matching mode, it is determined whether or not the inspection has been completed. If the inspection has been completed, a flag indicating the completion of origin matching is set, and then a stop process is performed to determine whether or not the mode is the origin matching mode. If the mode is not the origin matching mode, the stop process is performed and the process ends.

When it is determined in the "stop / mode command determination process" that there is a stop command, the stop process is performed and the process proceeds to the "origin matching mode determination process". If the inspection has not been performed in the “inspection completed judgment processing”, the process returns to the “input / output processing” and the same processing is repeated.

The simulation mode is executed to perform a test after setting when the product specification is changed.

In the simulation mode, as shown in FIG. 9, after the pre-simulation processing is performed, it is determined whether or not the origin adjustment has been completed. If the origin adjustment has not been completed, the process ends. If so, it is determined whether driving is possible.

When the operation is performed, an operation process is performed. When the operation is not performed, a stop process is performed, and it is determined whether or not to set the step to “0”. When the step is set to “0”, the process of setting the step “0” is performed. When the step is not set, the step number is set.
The step update process is executed accordingly.

Subsequently, it is determined whether or not to execute the simulation mode. If the simulation mode is to be executed, the process returns to the "operation feasibility determination process", and the same process is repeated. Is done and ends.

[0054]

As described above, according to the present invention, all the production lines including the main line and the plurality of sub-lines can be operated synchronously with inexpensive equipment having a simple and simple structure, and the operating speed can be changed. Can be performed in a synchronized state. In addition, during maintenance, the status of the device or system can be visually inspected using a simple measuring instrument, so that the status can be grasped more reliably than control relying on software, and reliability should be improved. There is an effect that can be.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a main part of a process control device according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of a process control system provided with a process control device according to the present invention.

FIG. 3 is a diagram showing an example of a pulse pattern calculated by an algorithm for calculating a command pulse Psa for speed following in a program control circuit of the process control device according to the embodiment of the present invention.

FIG. 4 is a diagram showing an example of a pulse pattern calculated by a calculation algorithm of a command pulse Psb for acceleration / deceleration operation required for pattern operation in the program control circuit of the process control device according to the embodiment of the present invention.

FIG. 5 is a diagram showing a data transfer algorithm between a program control circuit and a pulse generation circuit of the process control device according to the embodiment of the present invention.

FIG. 6 is a flowchart showing a flow of an operation in an automatic mode of the process control apparatus according to the embodiment of the present invention.

FIG. 7 is a flowchart showing a flow of an operation in a manual mode of the process control apparatus according to the embodiment of the present invention.

FIG. 8 is a flowchart illustrating a flow of an operation in an origin matching mode of the process control apparatus according to the embodiment of the present invention.

FIG. 9 is a flowchart showing an operation flow in a simulation mode of the process control apparatus according to the embodiment of the present invention.

[Description of Signs] 1 input terminal 2 output terminal 3 pulse generation circuit 3a gate circuit 3b shift register 3c buffer circuit 5 arithmetic circuit 5a program control circuit 5b memory circuit 10 process control device 11 drive circuit 12 motor 13 servo encoder 20 conveyor device 20a Main drive motor 20b Main speed detection encoder 21 Guide A device 22 Guide B device 23 Guide C device

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-11375 (JP, A) JP-B-46-10968 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) G05D 3/00-3/20 G05B 19/18-19/416

Claims (5)

(57) [Claims] An input terminal for inputting operating speed information serving as a reference for a controlled system, and an output terminal for outputting operating control information to one device belonging to the controlled system according to the operating speed information. In the process control device, the operation speed information is a reference pulse train arriving at a frequency proportional to the operation speed, and a part of the reference pulse train is omitted at a ratio corresponding to an operation speed ratio with respect to the reference pulse train, and the operation control information is deleted. Command pulse train output means for outputting a pulse train that becomes, the command pulse train output means accelerates the operating speed or
When decelerating , the acceleration or deceleration phase is
Outputs a predetermined number of pulses corresponding to the gear ratio for the quasi-pulse
Speed ratios of different gear ratios
Should be set so that the pulse intervals in the deceleration stage are averaged.
A process control device comprising means for outputting the pulse train in combination . (2)The command pulse train output means,  A gate provided between the input terminal and the output terminal
Circuit and bit information indicating the lack or passage of the reference pulse is stored.
And the signal of the input terminal is used as a clock signal.
A system for sequentially providing bit information to the control input of the gate circuit
Shift register, and an operation of sequentially inputting the bit information into the shift register.
The process control device according to claim 1, further comprising a calculation circuit. 3. The arithmetic circuit includes a program control circuit, and a memory circuit that stores a program and a control pattern of the program control circuit.
3. The process control device according to claim 2 , including an automatic mode, a manual mode, an origin matching mode, and a simulation mode. 4. The process control device according to claim 1, wherein an output terminal is connected to a drive circuit, and an output of the drive circuit is supplied as a drive current to a motor of one device belonging to the controlled system. A process control system wherein a position signal of a device driven by the control circuit is connected back to the drive circuit. 5. A plurality of process control systems according to claim 4, further comprising one common device (conveyor) commonly associated with the plurality of process control systems, wherein the common device includes a plurality of process control systems as the reference pulse. Factory equipment provided with a means for generating a pulse train commonly supplied to a process control device.