JP2516128B2 - Combination weighing or counting device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combination weighing or counting apparatus which can execute a normal program even if electric noise occurs.

[0002]

2. Description of the Related Art An article is supplied to a weighing hopper provided in each of a large number of weighing machines, and a combination calculation is performed based on a measured value by each weighing machine. Has been put to practical use, in which the weighing machine is selected and the weighing hopper of the weighing machine corresponding to the optimum combination is opened to discharge the articles.

In such a combination weighing device, the weighing hopper which has discharged the objects to be weighed corresponding to the optimum combination is immediately loaded with the articles for the next weighing from the pool hopper arranged above the weighing hopper, and these pools are weighed. Articles are individually supplied to the hopper from an electromagnetic feeder as a dispersion supply device arranged in the upper stage. FIG.
Is a schematic diagram of the combination weighing device, and the weighing values X _{1 to} Xn obtained by the weighing hoppers W _{1 to} Wn of the respective weighing machines are input to the multiplexer 2. When the arithmetic and control unit 4 composed of a microcomputer applies the signal S to the multiplexer 2 by the timing signal T from the packaging machine 5, each weighing signal is sequentially taken into the A / D converter 3 and the digital signal is arithmetically controlled. Sent to device 4. The arithmetic and control unit 4 stores the digital signal in the storage unit 6 and
The necessary command is read out from the above, the combination addition operation is performed to obtain the combination total weight value, and it is compared with the target weight value Xs to obtain the combination having the combination total weight value closest to the target weight value Xs. If this combined total weight value does not exceed the upper limit weight set value Xu, this combination is the optimum combination. When the optimum combination is obtained, a predetermined control signal C is given to the drive unit 7 of the weighing machine corresponding to the combination, the articles are discharged from the weighing hopper, and then the pool hopper and the electromagnetic feeder are sequentially controlled to perform the next weighing. Items for weighing are sequentially loaded from the pool hopper to the weighing hopper, and items for weighing one after another are sequentially loaded from the electromagnetic feeder to the pool hopper.

[0004]

In such a combination weighing device, there is a limit in processing capacity to control each weighing machine by one microcomputer, so that the weighing speed is increased or the weighing machine is used in particular. It was impossible to add more units. Further, when a control system is configured using a CPU (Central Processing Unit), the CPU must self-recover in order to obtain safety of the entire system when the CPU runs away due to a noise signal or the like. Conventionally, there has been no effective means for such self-recovery. This will be described in more detail. Generally, as shown in FIG. 2, a microcomputer executes an instruction stored in a ROM (read-only memory) as a C instruction.
The operation is started by reading to PU.

When the CPU outputs the address signal to the address bus in the order of execution, the ROM automatically outputs the command word to the data bus. By the way, since the combination weighing device has an electromagnetic feeder driven by a phase-controlled SCR (thyristor), an electrical noise signal may be generated and enter the CPU, and an incorrect command may be read. Occurs. For example, as shown on the left side of FIG. 3, an instruction word 1 consisting of 3 bytes, 2 bytes, 2 bytes, 3 bytes, ...
3 to 4 are formed, as shown on the right side of FIG. 3, the instruction word 2 is misread by 3 bytes, or the CALL instruction or the JU is read.
If the addressing instruction such as the MP instruction is erroneously read, the microcomputer system cannot operate normally.

According to the present invention, the load can be reduced and the weighing capacity can be improved by using a plurality of microcomputers for distributed processing, and the number of weighing machines can be easily increased. It is an object of the present invention to provide a new combination weighing or counting device capable of self-returning for each weighing machine even if it malfunctions due to mixing of noise or the like.

[0007]

In order to achieve the object of the invention as described above, the present invention measures the weight of articles put into a plurality of weighing machines, and obtains each weight value or each weight value obtained. a combination of the number of the converted article from selected nearest optimal combination target value combination total value, so as to discharge the articles from the weighing machines of the selected combination, the central processing unit separately for each weighing machine Is provided, each individual central processing unit is connected to the main central processing unit that controls the whole, and each individual central processing unit is individually driven by interrupt processing based on the operation command transmitted from the main central processing unit. Interrupt control means to control
In the combination weighing or counting device having, the interrupt control means operates according to an interrupt control command at a request from a data bus line connected to the main central processing unit .
Interrupt control means and second interrupt control means that operates in synchronization with the zero-cross point of the AC power supply of the drive unit.
A combination weighing or counting device having control means, each interrupt control means comprising means for resetting each individual central processing unit to a normal interrupt processing execution state when an interrupt occurs. Is.

[0008]

In the combination weighing device or combination counting device,
Based on the operation command transmitted from the main central processing unit, each central processing unit provided in the weighing machine is configured to be individually drive-controlled by interrupt processing, and when the interrupt processing command is issued, Each central processing unit is reset to a state in which normal interrupt processing can be executed.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. Generally, a microcomputer starts an interrupt program when an interrupt is generated by an electric signal from the outside, but the interrupt process has the highest priority and the start address of the interrupt program is specified. It does not malfunction due to noise. The present invention uses the characteristics of such an interrupt processing program, and FIG. 4 shows a flowchart of the operating procedure. That is, when the interrupt request 1 is issued in the interrupt waiting state, the CPU accepts this request and executes the process 1 according to a predetermined program, and when the process 1 is completed, the process returns to the address of the waiting program for the interrupt and returns again. Wait for an interrupt. Then interrupt 2,
Even if a request for an interrupt 3 is issued, the same process 2, process 3 is performed.
Is executed, and after returning to the address of the standby program that is always waiting for an interrupt, it is put in the state of waiting for an interrupt. As compared with the conventional example, the interrupt process of the related art is such that, as shown in FIG. 5, the interrupt factors 1 to 5 are continuously accepted by the CPU and the program is executed by jumping to a specific address. However, in the interrupt processing of the present invention, as shown in FIG. 6, addresses for interrupts are set independently for each of interrupt factors 1-5. That is, all processing programs by the microcomputer are created by interrupt programs, and necessary processing operations are started by always applying an electric signal to the interrupt input terminal.

Next, the embodiment of the present invention will be described more specifically with reference to FIGS.

Since the combination weighing device according to the present invention has an independent drive unit for each weighing machine, a sub central processing unit (CPU) is provided for each drive unit to execute a combination calculation. By connecting to a main CPU that collectively manages each weighing machine, the control of the drive unit up to now is distributed to each sub central processing unit (CPU). FIG. 7 (A)
Is a schematic diagram of such a computer control system.
PU-1 to CPU-n are connected by a data highway, which is connected to the main CPU-0 by a bus line.

Next, the drive unit of each weighing machine is shown in FIG.
It is configured as shown in FIG. That is, each drive unit uses (1) the feeder time / feeder strength control device of the electromagnetic feeder that supplies articles to the pool hopper and the rotational force of the main motor (not shown) that is constantly rotating to the gate of the pool hopper. (2) Pool hopper clutch, which brakes the gate, (3) Pool hopper brake, (4) Pool hopper motion sensor, and also transmits the rotational force of the main motor to the gate opening / closing mechanism of the weighing hopper. , (5) weighing hopper clutch, braking the hopper gate, (6) weighing hopper brake, (7) weighing hopper operation sensor, and the like. The feeder is a feeder time / feeder strength control device (1).
The pool hopper is controlled via the pool hopper clutch (2) and the pool hopper brake (3) to control the opening and closing of the gate, and at that time, the pool hopper operation sensor (4) normally controls the pool hopper. A check is made to see if it has worked. Further, the weighing hopper is controlled to open and close via the weighing hopper clutch (5) and the weighing hopper brake (6), and at that time, whether the weighing hopper has normally operated by the weighing hopper operation sensor (7). Confirmation is done.

FIG. 8 is a flow chart showing the mutual processing procedure of the main CPU and the sub CPU in the drive unit. When the timing signal from the packaging machine is given to the main CPU, the main CPU instructs each sub CPU. Send a weight data request signal. When each sub CPU receives the signal from the main CPU by interruption, each sub CPU takes in the weighing data into each A / D converter, converts it into digital weight data, and sends it to the main CPU (processing step (a)). . Main CPU is each sub-CP
The weight data from U is stored, a combination operation is performed based on these data, the weighing machine which is the optimum combination is selected, and a drive request signal is sent to the corresponding weighing machine. The sub CPU that receives this signal by interruption controls the weighing hopper drive, pool hopper drive, and feeder preset, and when this is completed, a completion command is issued to the main CP.
It is sent to U (processing step (b)).

FIG. 9 is a flow chart showing a concrete procedure of an interrupt process of the sub CPU in each drive unit. The interrupt process is a request signal from a data bus or an AC 200.
It is initiated by the signal generated at the zero-crossing point when changing from a negative voltage of V to a positive voltage. Here, since the zero-cross point is detected with respect to the AC power source that drives the electromagnetic feeder, an interrupt signal is generated 60 times per second when the power source is 60 Hz, for example. This interrupt signal is applied during the HALT (stop) routine of the CPU in a normal operating state, but is interrupted during a runaway in the event of an abnormality. When the CPU is interrupted, the stack register address is checked. This is the CPU HAL
This is because it is checked whether or not the CPU has run out by checking whether the T state is executed at a normal address. If it has runaway, it is rewritten to the correct address, that is, the address of the HALT routine, and each input / output port is set to the initial value.

Next, the interrupt factor is checked, and the main C
When a data bus line request is issued from the PU, a command is received and the step (a) or (b) in FIG. 8 is executed. HA if steps (a) and (b) are completed
Return to the LT routine. In the case of 200V zero cross, it is first confirmed whether or not the count value of the feeder drive counter is zero. This feeder drive counter is set to a predetermined value in the feeder preset step after receiving the hopper drive command in the step of FIG. When the count value of the feeder drive counter is not zero, the counter is decremented, the firing angle timer of the SCR for driving the electromagnetic feeder is operated, and the SC is set at the phase angle t as shown in FIG.
I fire R and return to the HALT routine. The feeder operates for a predetermined period of time during the cycle set by the counter. For example, if the operation period is 0.3 seconds, the feeder is driven for 18 cycles in the case of a 60 Hz power supply. It should be noted that in FIG. 9, when the count value of the counter is zero or when the firing of the SCR is completed, the process returns to the HALT routine.

Further, the weight of the articles in each weighing hopper is divided by the unit weight to be converted into the number of articles, and the converted number is subjected to a combination operation to obtain an optimum value which is equal to or closest to the target number set. The present invention can also be implemented in a combination counting device that seeks a combination.

[0017]

As described above, in the combination weighing or counting apparatus of the present invention, the sub CP for controlling the driving of the weighing machine is used.
Since U is provided for each weighing machine and these sub CPUs are connected to the main CPU so that each weighing machine is centrally managed by this main CPU, processing has conventionally been performed by one computer. Control can be distributed among multiple computers. Therefore, it is possible to improve the processing speed of the entire apparatus and easily add a weighing machine.

Furthermore, since data transmission from the main CPU to the sub CPU is performed by interruption, it is possible to prevent erroneous reading of an instruction due to a noise signal and always start processing from the correct address. Therefore, it is possible to perform harmless weighing and discharging by coordinating the individually driven weighing machines.

Further, an interrupt signal is generated at each zero-cross point of the AC power source to check the CPU runaway, and if a runaway occurs, the correct interrupt waiting address is set again. The microcomputer can be returned to the normal state. Further, since it is possible to check whether or not the interrupt was correctly waited for when the interrupt occurred, it is possible to normalize the system and then execute the interrupt process. Since a plurality of sub CPUs that perform such interrupt processing are connected by a data highway and are connected to the main CPU by a data bus line,
Each sub-CPU is capable of self-restoring against a runaway, thus providing a highly reliable combination weighing or counting device.

[Brief description of drawings]

FIG. 1 is a functional schematic diagram of a combination weighing device.

FIG. 2 is a diagram illustrating a basic relationship between a CPU and a ROM.

FIG. 3 is a diagram illustrating a configuration of an instruction word.

FIG. 4 is a flowchart showing a procedure of an interrupt process according to the present invention.

FIG. 5 is a conventional example.

FIG. 6 is a diagram illustrating the concept of interrupt processing.

FIG. 7 is a schematic diagram of a control system of a combination weighing device to which the present invention is applied.

FIG. 8 is a flowchart showing a processing procedure of a main CPU and a sub CPU according to the present invention.

FIG. 9 is a flowchart showing a procedure of an interrupt process in the sub CPU.

FIG. 10 is a diagram illustrating phase angle control of a control SCR of an electromagnetic feeder.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Weighing machine 2 ... Multiplexer 3 ... A / D converter 4 ... Arithmetic control device 5 ... Wrapping machine 6 ... Storage device 7 ... Drive unit

Claims (2)

(57) [Claims] 1. An optimum method in which the weights of articles put into a plurality of weighing machines are weighed and the obtained weight values or the number of articles converted from the respective weight values are combined so that the combined total value is the closest to the target value. select combination, so as to discharge the articles from the weighing machines of the selected combination, a central processing unit provided individually for each of the weighing machine, connected to the main central processing unit which controls the whole of each individual central processing unit and, the combination meter have a interrupt control means for controlling individually driven by interrupt processing each individual central processing unit based on the operation command transmitted from the main central processing unit
In the quantity or counting device, the interrupt control means operates according to an interrupt control command requested by a data bus line connected to the main central processing unit.
And a second interrupt control means that operates in synchronization with the zero-cross point of the AC power supply of the drive unit.
However, each interrupt control means is provided with means for resetting each individual central processing unit to a normal interrupt processing execution state when an interrupt occurs, the combination weighing or counting apparatus. 2. The combination weighing or counting apparatus according to claim 1, wherein the interrupt control command generated in synchronization with the zero-cross point of the AC power supply is generated at a timing of a delay phase of a predetermined time t from the zero-cross point. .