JP2792530B2 - Work transfer status monitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a monitor for accurately displaying a work transfer position at a production site, for example.

[0002]

2. Description of the Related Art A conventional work transfer state monitoring apparatus monitors and displays a work transfer state which cannot be seen from the outside flowing in a facility in, for example, a heat treatment process. It has a configuration as shown in FIG.

The work 10 is conveyed on a set conveying path by a conveying device in a direction indicated by an arrow in the figure. Work detection sensors 15A to 15G for detecting the work 10 along the transport path are provided at predetermined intervals. These work detection sensors 15A to 15G are connected to programmable controllers 20A to 20E, respectively, and work detection signals from the respective work detection sensors 15A to 15G are input to the respective programmable controllers 20A to 20E. The monitor 25 calculates where the work 10 is currently located based on the signals from the programmable controllers 20A to 20E, and displays the result on the screen 25A of the monitor 25 as shown by a solid line in the drawing. Thereby, the operator can monitor, for example, where the work exists in the heat treatment furnace, whether the temperature of the work is normal, and the like.
It can be easily grasped above.

[0004]

However, in such a conventional work transfer state monitoring device, a very large number of work detection sensors provided along the transfer path are scanned and the work passes. The larger the number of sensors that constantly monitor whether or not the scanning is performed, the longer the scanning interval becomes, which causes an error between the display and the actual position of the work. On the other hand, if the signals of all the sensors are constantly read, the load on a processing device such as a workstation increases, which has a disadvantage that the processing speed of other processing is adversely affected. Therefore, although the actual position of the work is at the position indicated by the dotted line in FIG.
The display on 5A will be displayed as if it were present at the position of the solid line in FIG.

If this error is a very small error, it is possible to quickly find out which work even when a work abnormality is detected. In the case where the work is continuously flowing, it is very difficult to find the target work, which greatly affects the work efficiency.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a plurality of work detection sensors provided at predetermined intervals along a work transfer path and detecting a passage position of the work. A work transfer speed calculating means for calculating an average transfer speed of the work from a passage time of the work between the work detection sensors, and after the passage of the work is confirmed by any of the plurality of work detection sensors, A work transfer position calculating unit that calculates a current work transfer position based on the work transfer speed calculated by the work transfer speed calculation unit, and the passage of the work is detected by one of the plurality of work detection sensors. Calculation time measurement for measuring the time from when the current position of the work is calculated by the work transfer position calculation means And the current work transfer position calculated by the work transfer position calculation means based on the step and the calculation time measured by the calculation time measurement means and the work transfer speed calculated by the work transfer speed calculation means. A work transfer position error calculating means for calculating an error between the actual work transfer position and the current work transfer position calculated by the work transfer position calculation means and a current work transfer position calculated by the work transfer position error calculation means. Display means for displaying the actual work transfer position based on the error between the work transfer position and the actual work transfer position.

A determination means for determining whether the passage time of the work between the respective work detection sensors is within a set time, and the determination means determines that the passage time of the work is equal to or longer than the set time. In this case, without considering the error between the current work transfer position calculated by the work transfer position error calculation means and the actual work transfer position, the current work position calculated by the work transfer position calculation means is not considered. Display control means for controlling a display of the transport position on the display means.

[0008]

The present invention thus constructed operates as follows.

The work detection sensors are provided at predetermined intervals along the work transfer path, and detect a passing position of the work. The work transfer speed calculating means calculates an average transfer speed of the work from the passage time of the work between the respective work detection sensors. The work transfer position calculating means, after the passage of the work is confirmed by any of the plurality of work detection sensors, based on the work transfer speed calculated by the work transfer speed calculation means, the current work transfer Calculate the position. The calculation time measuring means measures the time from when the passage of the work is detected by any of the plurality of work detection sensors to when the current position of the work is calculated by the work transfer position calculating means. The work transfer position error calculation unit is configured to calculate the current time calculated by the work transfer position calculation unit based on the calculation time measured by the calculation time measurement unit and the work transfer speed calculated by the work transfer speed calculation unit. Is calculated between the actual work transfer position and the actual work transfer position. The display means displays the current work transfer position calculated by the work transfer position calculation means and the error between the current work transfer position calculated by the work transfer position error calculation means and the actual work transfer position. Based on this, the actual work transfer position is displayed.

Therefore, it is possible to always accurately display the transfer position of the work regardless of the time required for the arithmetic processing.

Further, in addition to the above configuration, the judging means judges whether the passing time of the work between the respective work detection sensors is within a set time, and the control means judges the passing time of the work by the judging means. If it is determined that the time is equal to or longer than the set time, the work transfer position is calculated without considering the error between the current work transfer position calculated by the work transfer position error calculation means and the actual work transfer position. Control is performed so that the current work transfer position calculated by the position calculation means is displayed on the display means.

For this reason, for example, even when the work is not conveyed due to some conveyance abnormality, the abnormality can be detected. In this case, it is not always accurate, but it is difficult to determine where the work is located. It becomes possible to know more accurately than performing position correction.

[0013]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of a work transfer state monitoring device according to the present invention. As is clear from this figure, the device of the present invention has exactly the same hardware configuration as FIG. 5 showing a conventional device. Although the appearance is the same as the device shown in FIG. 5, the device configuration in the monitor device 25 is different from the conventional device. Therefore, description of the configuration of FIG. 1 is omitted.

FIG. 2 is a block diagram showing an arithmetic processing portion which is a main part of the work transfer state monitoring device of the present invention.

Work detection sensors 15A to 15N (along with the work detection sensors 15A to 15N in FIG.
-15 G are described, but in fact a great number of sensors are arranged) are connected to a programmable controller group 20 composed of a plurality of programmable controllers. A signal from each work detection sensor is input to these programmable controller groups 20. A monitor device 25 is connected to the programmable controller group 20.

The monitor 25 is provided with a work transfer speed calculation unit 30 and a display calculation processing unit 32. The work transfer speed calculation unit 30 determines the passage time of the work 10 passing between the work detection sensors. Of each work 10 based on the passing time and the sensor arrangement data stored in the sensor arrangement data storage unit 31, that is, the arrangement intervals of the work detection sensors 15A to 15N. It calculates the average transport speed of the passing workpiece, and functions as a calculation time measuring unit and a workpiece transport speed calculating unit.

The display arithmetic processing unit 32 calculates the average transport speed of the workpiece calculated by the workpiece transport speed calculating unit 32 and the average value of any one of the workpiece detection sensors referred to in calculating the average transport speed of the workpiece. The time at which the detection signal is output and the time at which the above-described average transfer speed of the work has been calculated are input, and the distance over which the work has moved until this calculation is performed, that is, the position error is calculated. Yes, it functions as a work transfer position error calculation unit. The display calculation processing unit 32 calculates the actual position of the work based on the obtained position error and the work transfer position calculated by the work transfer speed calculation unit 30, and displays the calculated position on the display unit 34. And also has a function as a display means. Further, the display calculation processing unit 32 functions as a judging means for judging whether or not the passing time between the work detection sensors is within a set value. It also has a function as a display control means for displaying the position of the work calculated based on the average transfer speed of the work from 30 on the display unit 34.

The work transport state monitoring apparatus according to the present invention, which is constructed as described above, operates as follows in accordance with the flowchart shown in FIG. The work transfer speed calculating unit 30 is configured to detect the work
A work detection signal detected by 5A to 15N is input via the programmable controller 20 (S
1) The time when the work is detected is stored together with the detection signal (S2). The work transfer speed calculation unit 30 calculates the work transfer speed based on the work detection signals sequentially output from the respective work detection sensors according to the transfer of the work and the sensor arrangement data stored in the sensor arrangement data storage unit 31. Is calculated. For example, when the work 10 is conveyed in the direction indicated by the arrow in FIG. 1, the work detection sensors 15B, 15C, 15C
The workpiece detection signals are input to the workpiece transport speed calculation section 30 in the order of D,..., But at this time, since the detection time is given to each workpiece detection signal, the workpiece detection sensor 15B Based on the time difference between the time when the work 10 is detected and the time when the work detection sensor 15C detects the work 10 and the information on the arrangement interval between the two work detection sensors stored in the sensor arrangement data storage unit 31. Then, the transport speed of the work 10 is calculated (S3).

The display operation processing section 32 inputs the work transfer speed calculated by the work transfer speed calculation section 30 and performs an operation for displaying the position of the work 10 on the display section 34 (S4). The display operation processing unit 32 gives the time when this operation is completed to the data obtained by this operation (S5). Next, the display calculation processing unit 32 obtains a time difference between the detection time of the work detection signal used for performing the calculation and the time when the calculation for the display is completed, and the work 10 moves during this time. Is performed (S6). When this calculation is completed, the display calculation processing unit 32 adds the distance calculated in step S6 to the position of the work calculated in step S5, and regards the position after the addition as the current position of the work 10. It is displayed on the display unit 34 (S7).

In this way, the work lag calculating section 30 can completely eliminate the time lag caused by the calculation by performing the correction calculation. If the display is performed after performing such calculations, the current position of the work 10 can always be accurately grasped.
This is particularly effective when the transfer speed of the work 10 is high or when the number of the work detection sensors 15A,.

FIG. 3B is a flowchart showing a process in the case where the work detection signal output from the work detection sensor is not output even after a certain period of time.

The work transfer speed calculating section 30 constantly monitors whether a work detection signal is output from any of the work detection sensors (S10). If a work detection signal is input, the count time is reset and the next time. The time until the work detection signal is input is counted. Specifically, when the work 10 is normally conveyed, FIG.
As shown in (1), the sensor detection signals should be output in the order of N-1, N, N + 1 at regular intervals, but if this is abnormal in the transport state, the generation of the sensor detection signals will be irregular. Or it is not generated at all, so this is detected (S11 to S13). If the sensor detection signal is not output even after the lapse of the set time, it is presumed that an abnormality has occurred in the transfer state of the work. In this case, the display calculation processing unit 32 The display unit 34 displays the position of the work output from the work transfer speed calculation unit 32 as it is. That is, the position of the work 10 obtained in step S5 is displayed on the display unit 34 as it is, ignoring the correction calculated in step S6 of the flowchart of FIG.
14). In this way, when an abnormality occurs in the transfer state of the work, the correction of the transfer position of the work becomes a problem, and the problem is solved.

As described above, when the work is conveyed normally, it is possible to eliminate the display position error caused when the position of the work is calculated. On the other hand, when the work conveyance state is abnormal. In order to solve the problem caused by correcting the position error of the display of the work, the display is performed without performing the position correction.

The set time may be determined in advance from the distance between the sensors and the set transfer speed of the work, or calculated at an optimum timing using the average transfer speed of the work obtained by the work transfer speed calculating means. You may do so.

[0025]

As described above, according to the present invention, the position correction calculation is performed in consideration of the time lag that occurs when calculating the work transfer position, so that the accurate work transfer position is always known. be able to.

In addition, when the abnormality of the transfer state of the work is recognized, the transfer position of the work is displayed without performing the position correction calculation. In this case, the transfer position of the work is relatively accurate. You can know.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a work transfer state monitoring device according to the present invention.

FIG. 2 is a block diagram showing an arithmetic processing portion which is a main part of the work transfer state monitoring device of the present invention.

FIGS. 3A and 3B are flowcharts showing the operation of the device of the present invention.

FIG. 4 is a diagram provided for explanation of the operation in FIG. 3 (B).

FIG. 5 is a schematic configuration diagram of a conventional work transfer state monitoring device.

[Explanation of symbols]

10 Work, 15A-1
5N: Work detection sensor 20: Programmable controller group, 20A to 20
C: programmable controller, 25: monitor device,
25A: monitor screen, 30: work transfer speed calculation unit, 31: sensor arrangement data storage unit, 32: display calculation processing unit
34 display unit.

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B65G 43/08 G01C 22/00

Claims (2)

(57) [Claims] A plurality of work detection sensors provided at predetermined intervals along a transfer path of the work to detect a passing position of the work; and A work transfer speed calculating means for calculating an average transfer speed of the work, after the passage of the work is confirmed by any of the plurality of work detection sensors, the work transfer speed calculated by the work transfer speed calculating means A work transfer position calculating unit that calculates a current work transfer position based on the current work position, and a work transfer position calculating unit that calculates a current position of the work after the passage of the work is detected by any of the plurality of work detection sensors. Calculation time measuring means for measuring the time until the operation is performed, and Calculating the error between the current work transfer position calculated by the work transfer position calculation means and the actual work transfer position based on the calculated time and the work transfer speed calculated by the work transfer speed calculation means. A work transfer position error calculating means, a current work transfer position calculated by the work transfer position calculation means, a current work transfer position calculated by the work transfer position error calculation means, and an actual work transfer position. A display means for displaying an actual work transfer position based on an error of the work transfer state. 2. A determining means for determining whether the passing time of the work between the respective work detection sensors is within a set time, and the determining means determines that the passing time of the work is equal to or longer than the set time. in case of,
Without considering the error between the current work transfer position calculated by the work transfer position error calculation means and the actual work transfer position, the current work transfer position calculated by the work transfer position calculation means is calculated by the work transfer position calculation means. 2. The apparatus according to claim 1, further comprising display control means for controlling display on the display means.