Data collection and transfer apparatus

A data collection and transfer apparatus includes: a memory; a buffer having large capacity and low data storage speed; a collecting unit collecting data and storing it in the memory; a transferring unit transferring data stored in the memory to a server; a monitoring unit monitoring a network; and a setting unit retaining storages. When fault is not detected, the collecting unit collects data specified in collection-data-setting storage with period specified in collection-period-setting storage and stores it in the memory and the transferring unit transfers data stored in the memory to the server with period specified in transfer-period-setting storage, and when fault is detected, the collecting unit collects data specified in buffer-data-setting storage with period specified in buffer-period-setting storage and stores it in the memory and data stored in the memory is stored in the buffer with period specified in the buffer-period-setting storage.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a National Stage of International Application No. PCT/JP2012/080346 filed Nov. 22, 2012, the contents of all of which are incorporated herein by reference in their entirety.

FIELD

The present invention relates to a data collection and transfer apparatus that collects control data (input/output data and internal data) related to a control device and transfers the control data to a personal computer for monitoring and analyzing (hereinafter, referred to as an upper-level server) for the operating state of the control device and the state of the control target to be monitored and analyzed.

BACKGROUND

Data collection and transfer apparatuses have been used that collect control data related to a control device and transfer the control data to the upper-level server, connected via a LAN, for the operating state of the control device and the state of the control target to be remotely monitored and analyzed. Such data collection and transfer apparatuses temporarily store data collected from the control device in a memory device (hereinafter, a temporary memory) capable of reading and writing at high speed and then transfers the data to the upper-level server at a given time.

The data collection and transfer apparatus collects data related to the control device and stores the data in the temporary memory, and then transfers the data to the upper-level server at a given time. However, when a fault occurs in the network between the data collection and transfer apparatus and the upper-level server, the data stored in the temporary memory cannot be transferred to the upper-level server. Moreover, when the memory capacity of the temporary memory is not sufficiently large, not all the data related to the control device collected while a network fault is occurring can be stored. In other words, there is a problem in that it is impossible to monitor and analyze the operating state of the control device and the state of the control target while a network fault is occurring.

In order to solve such a problem, the following data collection and transfer apparatus has been proposed. The apparatus is configured from a control device that performs a predetermined control and retains data related to this control and a data collection and transfer apparatus that has a function of, after collecting control data related to the control device and storing the control data in the temporary memory, transferring the data stored in the temporary memory to the upper-level server at a given time and a means (hereinafter, referred to as buffering) for, when a fault is detected in the network between the data collection and transfer apparatus and the upper-level server, storing, in order, the data stored in the temporary memory in a memory that can store large-capacity data (hereinafter, referred to as a large-capacity buffer memory).

A method for taking a measure against a fault in a measured data collection system is proposed in Patent Literature 1. This measured data collection system has a mode switching unit that switches the personal computer terminal in the personal computer, which is connected via a line to the host computer system, from the online mode to the local mode when a fault occurs and switches the personal computer terminal from the local mode to the online mode when the fault is rectified and a measured-data continuous collection and storage unit that continuously collects online-mode measured data and local-mode measured data before and after the occurrence of a fault and stores the data in an external storing device in the personal computer.

CITATION LIST

Patent Literature

SUMMARY

Technical Problem

However, due to the specifications of memories, the data storage speed of the large-capacity buffer memory is typically lower than the data storage speed of the temporary memory and thus not all the data stored in the temporary memory can be buffered. Therefore, when a network fault occurs, data cannot be buffered and the minimum amount of data required is lost in some cases. By using a memory having a large capacity and having a high data storage speed as a large-capacity buffer memory, it is possible to store all the data stored in the temporary memory in the large-capacity buffer memory; however, the memory having a large capacity and having a high data storage speed is generally expensive.

The present invention has been achieved in view of the above and an object of the present invention is to provide a data collection and transfer system capable of, when the data storage speed of a large-capacity buffer memory is lower than that of a temporary memory, storing the minimum amount of data required from the temporary memory in the large-capacity buffer memory when a network fault occurs.

Solution to Problem

In order to solve the above problems and achieve the object, the present invention relates to a data collection and transfer apparatus including: a temporary memory; a buffer memory that has a larger capacity than a capacity of the temporary memory and has a lower data storage speed than a data storage speed of the temporary memory; a data collecting unit that collects control data from a manufacturing apparatus and stores the control data in the temporary memory; a data transferring unit that transfers the control data stored in the temporary memory to an upper-level server; a network monitoring unit that monitors a network connecting the upper-level server and the data transferring unit; and a setting unit that retains a collection-data-setting storage, a collection-period-setting storage, a transfer-period-setting storage, a buffering-data-setting storage, and a buffering-period-setting storage, wherein when a fault is not detected in the network by the network monitoring unit, the data collecting unit collects the control data specified in the collection-data-setting storage with a period specified in the collection-period-setting storage and stores the control data in the temporary memory and the data transferring unit transfers the control data stored in the temporary memory to the upper-level server with a period specified in the transfer-period-setting storage, and when a fault is detected in the network by the network monitoring unit, the data collecting unit collects the control data specified in the buffering-data-setting storage with a period specified in the buffering-period-setting storage and stores the control data in the temporary memory and the control data stored in the temporary memory is stored in the buffer memory with a period specified in the buffering-period-setting storage.

Advantageous Effects of Invention

According to the data collection and transfer apparatus of the present invention, when a fault occurs in the network between the data collection and transfer apparatus and the upper-level server, i.e., when data cannot be transferred to the upper-level server, control data is stored in the large-capacity buffer memory in the data collection and transfer apparatus. Because different pieces of control data are collected with different collection periods when the network is normal and when a fault occurs, an effect is obtained where, even when the buffer rate is lower than the data transfer rate, the minimum amount of control data required can be prevented from being lost when a buffer operation is performed.

DESCRIPTION OF EMBODIMENTS

Exemplary embodiments of a data collection and transfer system in which a data collection and transfer apparatus according to the present invention is used will be explained below in detail with reference to the drawings. This invention is not limited to the embodiments.

Embodiment

FIG. 1is a diagram illustrating an example of the configuration of a data collection and transfer system1in which a data collection and transfer apparatus10according to an embodiment of the present invention is used. The solid line arrows inFIG. 1indicate the flow of control data when a fault has not occurred in the network between the data collection and transfer apparatus10and an upper-level server102. The broken line arrows indicate the flow of control data when a fault is occurring in the network. The control data here is, for example, input/output data and internal data related to a control device.

As illustrated inFIG. 1, the data collection and transfer apparatus10according to the present embodiment includes a data collecting unit20that is connected to a manufacturing apparatus100via a programmable controller103, that collects control data from the programmable controller103that controls the manufacturing apparatus100, and that stores the control data in a temporary memory18; a data transferring unit21that transfers the control data stored in the temporary memory18to the upper-level server102; a setting unit11that is connected to a setting personal computer101and retains the settings set in the setting personal computer101; a network monitoring unit22that detects a fault in the network between the data collection and transfer apparatus10and the upper-level server102; and a buffer unit that buffers the control data stored in the temporary memory18in a large-capacity buffer memory19when a network fault occurs. The large-capacity buffer memory19is a memory that has a larger capacity than that of the temporary memory18but has a lower data storage speed than that of the temporary memory18. The programmable controller103and the data collection and transfer apparatus10are connected via an internal bus110, the setting personal computer101and the data collection and transfer apparatus10are connected via an Ethernet (registered trademark) cable111, and the data collection and transfer apparatus10and the upper-level server102are connected via an Ethernet (registered trademark) cable112.

The programmable controller103is connected to the manufacturing apparatus100and controls the manufacturing apparatus100. The data generated as a result of the control and the data that is referred to when the control is performed are control data. In the present embodiment, the control data is data to be collected. The data collection and transfer apparatus10connected to the programmable controller103collects control data and transfers the control data to the upper-level server102. In the data collection and transfer system1illustrated inFIG. 1, the configuration is such that one manufacturing apparatus (the manufacturing apparatus100) is connected to one programmable controller103connected to the data collection and transfer apparatus10; however, in the data collection and transfer apparatus according to the embodiment of the present invention, the number of programmable controllers connected to the data collection and transfer apparatus and the number of manufacturing apparatuses connected to the programmable controller can be any number.

The network monitoring unit22monitors the presence or absence of the occurrence of a fault in the network between the data collection and transfer apparatus10and the data collecting unit20.

The setting unit11retains setting data set by the user using the setting personal computer101. The setting unit11includes a network normal setting group12and a network fault setting group23.

During a period when the network monitoring unit22does not detect a network fault, the network normal setting group12is referred to by the data collecting unit20and the data transferring unit21. During a period when the network monitoring unit22detects a network fault, the network fault setting group23is referred to by the data collecting unit20.

The network normal setting group12includes a collection-data-setting storage13that stores the setting regarding which control data among the control data is to be collected by the data collecting unit20; a collection-period-setting storage14that stores the setting of the period with which control data is collected by the data collecting unit20; and a transfer-period-setting storage15that stores the setting of the period with which the control data collected in the temporary memory18is transferred to the upper-level server102by the data transferring unit21.

The network fault setting group23includes a buffering-data-setting storage16that stores the setting regarding which control data among the control data is to be collected by the data collecting unit20and a buffering-period-setting storage17that stores the setting of the period with which control data is collected.

It is possible to set, using the setting personal computer101, whether the control data that is stored in the large-capacity buffer memory19while a network fault is occurring, i.e., the control data that has not been transferred to the upper-level server102, is transferred to the upper-level server102immediately after the network monitoring unit22detects network restoration or at a given time specified by the user, and store the setting in the setting unit11.

During a period when the network monitoring unit22detects a network fault, control data is stored in the large-capacity buffer memory19. The large-capacity buffer memory19is an external storage medium that has a storage area sufficient for storing control data and is detachably attached to the data collection and transfer apparatus10. The large-capacity buffer memory19is, for example, a Compact Flash (registered trademark) card or an SD card.

Next, an explanation will be given, with reference toFIG. 2, of a series of flows from the collection of control data to the data transfer or the storing of the data in the large-capacity buffer memory19within the data collection and transfer apparatus10according to the present embodiment configured as above.FIG. 2is a flowchart illustrating the outline of the process performed by the data collection and transfer apparatus10according to the present embodiment.

First, the setting unit11obtains setting data generated by the user using the setting personal computer101(Step S11). Next, whether the network monitoring unit22detects the occurrence of a network fault is checked (Step S12). When a network fault is not detected (No at Step S12), the data collecting unit20collects the control data specified in the collection-data-setting storage13of the network normal setting group12with a period specified in the collection-period-setting storage14(Step S13). The collected control data is stored in the temporary memory18and is transferred to the upper-level server102by the data transferring unit21on the basis of the period specified in the transfer-period-setting storage15(Step S14).

When a network fault is detected at Step S12(Yes at Step S12), the data collecting unit20collects the data specified in the buffering-data-setting storage16of the network fault setting group23in the temporary memory18with a period specified in the buffering-period-setting storage17(Step S15). The collected data is stored in the large-capacity buffer memory19on the basis of the period specified in the buffering-period-setting storage17(Step S16). The processes from Step S12to Step S16are repeated (No at Step S17) until the data collection is stopped (Yes at Step S17).

Next, an explanation will be given of the settings of the network fault setting group23. The buffering-data-setting storage16that specifies data to be buffered when a network fault is detected and the buffering-period-setting storage17that specifies a buffering period are respectively set independently from the collection-data-setting storage13and the collection-period-setting storage14, which are settings when a network fault is not detected. The buffering-data-setting storage16and the buffering-period-setting storage17can be set to exactly the same values as the collection-data-setting storage13and the collection-period-setting storage14, respectively; however, when the data storage speed of the large-capacity buffer memory19is low and not all the collected data can be stored in the large-capacity buffer memory19, they can be set to different values. Whether all the collected data can be buffered can be determined using the setting personal computer101.

Specifically, the setting personal computer101can automatically calculate the period with which data to be buffered is collected in accordance with the maximum storage speed with which data can be stored in the large-capacity buffer memory19and can set the calculated period in the buffering-period-setting storage17. Moreover, the user can determine whether the data specified in the buffering-data-setting storage16can be collected with a period specified in the buffering-period-setting storage17on the basis of the data storage speed of the large-capacity buffer memory19. The setting personal computer101has a function of notifying the user of the automatically set values and the determination result.

When it is determined that not all the collected data can be stored in the large-capacity buffer memory19if the buffering-data-setting storage16and the buffering-period-setting storage17are respectively set to the same values as the collection-data-setting storage13and the collection-period-setting storage14, the following setting can be made. That is, it is possible to reduce the control data specified in the buffering-data-setting storage16, i.e., data to be buffered, to be less than the control data specified in the collection-data-setting storage13in accordance with the degree of importance of the collection determined by the user. Alternatively, the period specified in the buffering-period-setting storage17, i.e., the collection period with which data to be buffered is collected, may be set to be longer than the period specified in the collection-period-setting storage14. Alternatively, both of the above processes may be performed. It is possible to prevent high-value data from being lost by setting the buffering-data-setting storage16and the buffering-period-setting storage17in such a manner.

In the present embodiment, after the network is restored, the data buffered in the large-capacity buffer memory19is transferred to the upper-level server102at a time specified by the user. The user can arbitrarily specify whether the buffered data is transferred to the upper-level server102immediately after the network is restored or at a time specified by the user.

Furthermore, the invention of the present application is not limited to the above embodiments and can be variously modified at the execution stage without departing from the scope thereof. Moreover, the above-described embodiments include inventions in various stages and various inventions can be extracted by appropriately combining a plurality of disclosed components. For example, even if some of the components are deleted from all the components illustrated in the embodiments, the configuration in which some components are deleted can be extracted as an invention as long as the problems described in the section of Technical Problem can be solved and the effects described in the section of Advantageous Effects of Invention can be obtained. Furthermore, the components in different embodiments may be appropriately combined.

INDUSTRIAL APPLICABILITY

As described above, the data collection and transfer apparatus according to the present invention is useful as a data collection and transfer apparatus that collects control data related to a control device and transfers the control data to the upper-level server for the operating state of the control device and the state of the control target to be monitored and analyzed and is particularly suitable as a data collection and transfer apparatus that monitors and analyzes the operating state of the control device and the state of the control target while a network fault is occurring.

REFERENCE SIGNS LIST