JPH02306112A - Adjusting apparatus for sensitivity of sensor - Google Patents

Abstract

PURPOSE:To adjust the sensitivity easily and to shorten the adjusting time by providing a display part thereby to make an input signal visually confirmable, and an adjusting part to adjust the sensitivity while monitoring the display of the part. CONSTITUTION:When a control signal 31a and a select signal 31b are turned high, a gain data from a sensitivity adjusting part 7 is, passing through a main processing part 24, a buffer 15 and a latch circuit 14, D/A converted at 13. An output of the D/A converter 13 determines a current of a light projecting circuit 11. An LED 10 is driven by this current with the timing of a pulse signal of an oscillator 12, and an illuminating light 32a from the LED 10 is projected to an object to be detected. When a reflecting light 32b of the light 32a is received, the current is amplified by an amplifier 20 and then input to a processing circuit 21 as a voltage output 32c. Then, an output from the circuit 21 is input to a processing part 24 and at the same time, if the output is not smaller than a threshold voltage, an operation displaying circuit 27 turns ON a display lamp 8. The output from the circuit 21 is input also to a self- diagnosing circuit 22. If the voltage value is within the stable output range, a stable displaying circuit 28 actuates a stable display lamp 9.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sensor sensitivity adjustment device, and particularly to facilitating and increasing the efficiency of the adjustment work.

[Conventional technology]

Generally, a sensor detects light emitted from an object to be measured.

It is configured to take in information such as displacement, sound, pressure, etc. as an input signal, convert this into an output signal such as an electrical signal with a predetermined sensitivity (gain), and output it to a processing device. Here, the above-mentioned sensitivity refers to the ratio of the change in the output signal to the change in the input signal, but this sensitivity may need to be adjusted depending on the measurement target 1, the target measurement accuracy, etc. Conventionally, such sensitivity adjustment is generally performed using, for example, a multi-rotation volume provided on the sensor body. Specifically, the above-mentioned volume is turned using a screwdriver or the like so that an operation indicator light and a stability indicator light provided on the sensor body are turned on.

C Problems to be Solved by the Invention] However, the conventional sensitivity adjustment described above has the following problems.

- Since the adjuster cannot check the magnitude of the input signal to the sensor, the adjustment must be done by trial and error, making the work difficult, requiring PM for adjustment, and lengthening the adjustment time.

(2) Since the above structure makes it difficult to support remote control, it is necessary for an adjuster to go to the location where the sensor is installed or to remove the device itself. Particularly when the sensor is installed in a narrow space, it is difficult for the adjuster to approach the installation location, which deteriorates the work efficiency accordingly.

- Due to the above structure, it is difficult to support automatic adjustment, so once it is set, it is difficult to switch the sensitivity midway through, and it is necessary to set it again manually.

■ Machine axis alignment is difficult.

The present invention has been made to solve the above-mentioned conventional problems.By visualizing the magnitude of the input signal, the sensitivity can be easily adjusted in a short time.
It is an object of the present invention to provide a sensor sensitivity adjustment device that can easily handle automatic adjustment.

[Means for solving problems]

The present invention provides a sensitivity adjustment device that adjusts the sensitivity of a sensor that converts an input signal from a measurement object into an output signal with a predetermined sensitivity to a desired level, in which the input signal or the sensitivity level is adjusted in an analog manner. The present invention is characterized by comprising a display section for displaying information, and a sensitivity adjustment section for changing the sensitivity so that the value displayed by the display section falls within a predetermined range.

Here, in the sensor sensitivity adjustment device according to the present invention, the display section displays the input signal or the sensitivity level in an analog manner, and a threshold mark indicating that the displayed value matches the threshold value. In addition, the display section and the sensitivity adjustment section may be configured to be remotely operated from outside the sensor, and the sensitivity adjustment section may be configured to display the sensitivity at the time of sensitivity adjustment. A storage means for storing the level may be added.

[Effect]

To adjust the sensitivity using the sensor sensitivity adjustment device according to the present invention, make sure that the displayed value of the input signal or sensitivity level displayed in an analog manner on the display unit, for example, as a barcode, falls within a predetermined range. Change the sensitivity level using the sensitivity adjustment section while checking. Since the received amount of the input signal can be visually checked in this way, sensitivity adjustment is easy, and machine axis alignment can be easily and reliably performed, so that the adjustment time can be shortened accordingly.

Further, in the present invention, if the display section is configured to also display the threshold mark, the adjustment work becomes easier and more reliable. In addition, if a remote control structure is used, for example, even if the sensor body is installed in a narrow space, the sensitivity can be adjusted from the outside by simply using a foil, and there is no need to remove the sensor body.Furthermore, if the sensitivity level is memorized, Even if the measurement target changes, the sensitivity can be automatically switched by programming, and there is no need to reset the sensitivity.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

1rgJ to 4 show a sensor sensitivity adjustment device according to an embodiment of the present invention, and this embodiment is applied to a photoelectric sensor configured to detect the presence or absence of an object based on the amount of received reflected light. This is an example.

First, in FIG. 1 showing the schematic configuration of the apparatus of this embodiment, 1
is a photoelectric sensor, which connects the light emitting part 1a to the detected object 2.
, and the reflected light from the detected object 2 is sent to the light receiving section 1b.
It is configured to receive light. 3 is a control unit connected to the photoelectric sensor 1 by a cable 4a and further connected to the setting unit 5 by a cable 4b, which supplies the amount of light received from the photoelectric sensor 1 to the setting unit 5; It is configured to store a sensitivity level, which will be described later, and to output a bar code display signal and a threshold mark display signal.

Based on various signals from the control unit 3, the setting unit 5 displays the amount of light received in an analog barcode, displays a threshold mark, and adjusts the light emitting gain or light receiving gain of the photoelectric sensor 1. This is for adjusting the sensitivity, and as shown in FIG. 2, the monitor section (display section) 6. Sensitivity adjustment section 7. and operation indicator light8.
A stability indicator light 9 is provided.

The monitor section 6 has a large number of light emitting segments 6a arranged in a straight line, and displays an input signal input via the control unit 3 in an analog bar code according to the amount of light received. Further, this monitor section 6 has a first. Second threshold marks 6b and 6c are provided so as to light up.

The first threshold mark 6b lights up in accordance with the peak point of the bar code at the time when the sensor output switches from ON to OFF or vice versa in a state where the detected object 2 is present. Further, the second threshold mark 6c is configured to light up when the sensor output switches as described above in a state where the object to be detected 2 is not present or in a state where another object to be detected is placed.

Further, the operation indicator light 8 has the peak point of the barcode display that extends depending on the amount of light received at the first point. The stability indicator light 9 lights up when the peak point is located between the second threshold marks, and the stability indicator light 9 lights up when the peak point is located within a predetermined range (for example, 60% range) in the center between both threshold marks. It is configured to light up.

The sensitivity adjustment section 7 is for changing the sensitivity, that is, the light emission gain or the light reception gain, and is equipped with an up button 7a and a down button 7b, and the gain increases while the up button 7a is held down. The brush gain decreases while the descending button 7b is held down.

FIG. 3 is a block circuit diagram of the photoelectric sensor 1, etc.,
In the figure, parts 1' and 3' are surrounded by dashed lines.

5' are the photoelectric sensors 1. and 5', respectively. Control unit 3. It corresponds to setting unit 5.

In the photoelectric sensor corresponding part 1', 10 is a light emitting LED.
This is based on the pulse signal of the oscillator 12, and the light emitting circuit 11
Driven by. 13 is a D/A converter that controls the light projection current from the light projection circuit 11, and 14 is a latch circuit that holds gain data input from the control unit corresponding portion 3' via the buffer 15. Also, 30
a and 30b are AND circuits, and 31a and 31b are control signals.

The select signal 15.16 is a buffer, and when the control signal 31a and the select signal 31b are high, the buffer 15 is turned on and the latch circuit 14 is also reset.

19 is a PD for light reception, 20 is an amplifier that amplifies the light reception current of the PD 19 at a predetermined rate and outputs a voltage, 21 is an output processing circuit that outputs an operation indication, and 22 is an output circuit that outputs an indication of stable operation. This is a diagnostic circuit. Further, 17 is a sample and hold circuit that holds the output from the amplifier 20 at the falling edge of the pulse signal from the oscillator 12;
is an A/D converter that converts the output from the sample and hold circuit 17 into digital signal data (data for monitoring the output of light received) and outputs it to the control unit corresponding portion 3'. The select signal 31b becomes high, and the control signal 3
When 1a becomes low, the buffer 16- is turned on and the data for monitoring the light reception output is sent out.

In addition, in the control unit corresponding portion 3', 2
4 is a main processing section, to which data for monitoring the light reception output via the buffer 16, an output signal from the output processing circuit 21, a stability display output signal from the self-diagnosis circuit 22 are input, and barcode data, threshold It is configured to output value data to the display section 6 and to store gain data from the sensitivity adjustment section (gain setting circuit) 7 in the memory 29 .

In addition, in the setting unit corresponding portion 5', 2
7, the output from the output processing circuit 21 is the first one. When the operation indicator light 8 is located between the second threshold marks,
The operation display circuit 28 lights up the above output. This is a stability display circuit that lights the stability indicator light 9 when the stability is between the second threshold marks and within a predetermined range.

Next, the sensitivity adjustment operation in the device of this embodiment will be explained.

First, the specific operating method of the sensitivity adjustment operation will be explained along with FIGS. 1 and 2.

First, the object 2 to be detected is placed at a predetermined position, and after switching to the gain adjustment mode, the sensitivity of the target photoelectric sensor 1 is raised or lowered by using the up button 7a and the down button 7b of the setting unit 5. Then the sensor output becomes O
The first threshold mark 6b is displayed on the monitor unit 6 at the time of switching from N to OFF or vice versa.0 Next, after removing the detected object 2 or replacing it with another detected object, the above When the operation is repeated, the second threshold mark 6C is displayed. The first threshold mark 6b is displayed at the lowest sensitivity position where the detected object 2 can be detected, and the second threshold mark 6C is determined to be present even though the detected object 2 is not present. Displayed at the position of maximum possible sensitivity. In this state, the received light amount or sensitivity level is set to the above-mentioned 1. Second threshold mark 6b.

Adjust the gain while looking at the bar code of the amount of received light so that it is approximately in the middle of 6c, and complete the gain adjustment by setting it.

Next, the operations of the sensor upper section, control unit section, and setting unit section will be explained in detail with reference to FIG. Control signal 31a and select signal 31b
becomes high, the gain data from the sensitivity adjustment section (gain setting circuit) 7 is transferred from the main processing section 24 to the buffer 15.
is input to the D/A converter 13 through the launch circuit 14,
The output from the converter I3 determines the light emission current of the light emission circuit 11, and the light emission current drives the light emission LEDIO at the timing of the pulse signal of the oscillator 12.
Irradiation light 32a from the IO is projected onto the object 2 to be detected.

When the reflected light 32b from the object to be detected 2 is received by the light receiving PD 19, the received light current is amplified at a predetermined rate by the amplifier 20, and then input as is to the output processing circuit 21 as a voltage output 32C. The output from the circuit 21 is input to the main processing section 24, and when the voltage is higher than the threshold voltage, the operation display circuit 27 turns on the operation indicator light 8. Further, the output from the processing circuit 21 is sent to the self-diagnosis circuit 22.
If the voltage value is within the stable output range, the stability indicator circuit 28 turns on the stability indicator lamp 9.

On the other hand, the voltage output from the amplifier 20 is also input to the sample hold circuit 17, and its peak value is held at the falling edge of the pulse signal from the oscillator 12. The output from the sample and hold circuit 17 is converted into a digital signal (signal for monitoring light output output) by the A/D converter 18, and when the control signal 31a is low and the select signal 31b is high, the buffer 16 is activated. The received light output monitoring data is sent to the main processing section 24. This monitoring data is then displayed as a barcode on the monitor section 6. Further, in this case, a threshold mark is displayed in synchronization with the time point at which the output signal is switched, and at the light reception peak point of the barcode at that time.

Next, the operation of the main processing section 24 in the sensitivity adjustment described above is as follows.
This will be explained along the flowchart of FIG.

When the flow starts, the main processing unit 24 sends a control signal 31 to prevent erasure of data in the launch circuit 14.
a to low (step Sl), switch to the sensitivity adjustment mode, set the select signal 31b to high, load the gain data from the memory 29 for initial setting, and store the output signal in the memory 29 (steps 52 to 4). S4).

Next, the control signal 31a is set to low, the buffer 16 is activated, reads the received light output monitoring data from the A/D converter 18, stores it in the memory, and outputs the barcode signal to the monitor section 6 ( Steps 85-S7).

Furthermore, the output from the sensitivity adjustment section (gain setting circuit) 7 is read, gain data is output to the buffer 15, and the control signal 31a is set to high (steps S8 to
510).

Then, the output from the processing circuit 21 is read and it is determined whether or not the output has been reversed (Step Sll, 512). If the output has not been reversed and the processing is to be continued, step S13
After that, the process returns to step S5 and repeats the above flow. On the other hand, if the output signal is reversed, the threshold mark is displayed in alignment with the peak point of the barcode at that time (step S14). Note that this threshold mark can be erased by resetting.

Here, in order to display the first threshold mark 6b, the object to be detected 2 is placed at a predetermined position and the rise button 7a is pressed. Then, in the main processing section 24, the process proceeds from step Sl to Wataru 12, where the output signal is reversed (OFF-O
512-513 → 55-512-313 until N)
...is repeated. When the output is reversed, the process advances from 312 to 514, and the first threshold mark 6b is displayed.

Furthermore, in order to display the second threshold mark 6C, the object to be detected 2 must be removed (at this time the output signal is turned OFF), and the up button 7a is further pressed, then the output signal is reversed (OFF
Step 55-312-51 until F→ON)
3-55... are repeated. When the output is reversed, the process proceeds to step 514, where the second threshold mark 6C is displayed.Furthermore, to set the sensitivity, press the down button 7b and set the center point between the two threshold marks 6b and 60. The processing operation ends when the barcode is displayed. As a result, in the main processing unit 24, the above step S5→5
During the repetition of steps 12→S13→S5, etc., the process advances from step 513 to Sl, where the sensitivity is set.

In this example, the received light signal is converted into data for the light output output monitor and displayed as a bar code on the monitor 6 for visualization, making it possible to adjust the sensitivity while visually checking the amount of received light, making the work easier. , adjustment time can be shortened.

Also, connect the setting unit and kit 5 to cable 4b.

Since it is connected to the photoelectric sensor 1 by 4a, remote control is possible, and there is no need for the adjuster to go to the installation location.
For example, even if the photoelectric sensor 1 is installed in a narrow place, adjustment work will not be difficult, and there will be no need to remove the sensor.

Furthermore, since the gain data is stored in the memory 29 of the control unit 3, even if the object to be measured changes, the sensitivity can be switched according to the program, eliminating the need for manual resetting.

FIG. 5 shows a modification of the block circuit diagram of the sensor corresponding portion. In this example, gain setting is not performed using an external digital signal, but is performed using a manual gain adjustment circuit 23 such as a multi-rotation volume. This volume 23 is provided in the amplifier part of the sensor, etc., and is adjusted while looking at the barcode monitor of the light reception output.

Note that the example in which the gain setting circuit shown in Fig. 3 is provided, and the example shown in Fig.
The structure shown in the figure in which the volume is provided may be combined with a structure in which switching is performed using a depth inch or the like.

Further, in the above embodiment, the setting unit 5 was connected to the photoelectric sensor 1 via the control unit 3.
In the present invention, the setting unit can be directly connected to the sensor with a cable, or if there is space for mounting in the amplifier section of the sensor, the setting unit can be built into the amplifier section and the head section can be connected externally by separating the amplifier. Various modifications are conceivable, such as displaying the received signal in an analog manner by displaying a bar code or the like, thereby making it easier to adjust the sensitivity.

Further, although the above embodiments have been explained using a photoelectric sensor as an example, the present invention can of course be applied to sensitivity adjustment of sensors other than photoelectric sensors.

〔Effect of the invention〕

As described above, according to the sensor sensitivity adjustment device according to the present invention, input signals can be adjusted by providing a display section.

Since the number is visualized by displaying a bar code or the like, and an adjustment unit is provided that changes the sensitivity while looking at the bar code display, the sensitivity adjustment work is easy and reliable, and the adjustment time can be shortened.

[Brief explanation of drawings]

1 to 4 are diagrams for explaining a sensor sensitivity adjustment device according to an embodiment of the present invention. FIG. 1 is a perspective view showing the overall configuration, and FIG. An enlarged view, FIG. 3 is a block configuration diagram thereof, FIG. 4 is a flowchart diagram thereof, and FIG. 5 is a block configuration diagram showing a modification of the sensor portion of the above embodiment. In the figure, 1 is a photoelectric sensor, 2 is an object to be detected (measured object), 32b is reflected light (human signal), 32C is an output signal,
6 is a monitor section (display section), 7 is a sensitivity adjustment section, 6b, 6c
is a threshold mark, and 29 is a memory (storage means).

Claims (4)

[Claims] (1) In a sensitivity adjustment device that adjusts the sensitivity of a sensor that converts an input signal from a measurement object into an output signal with a predetermined sensitivity to a desired level, the input signal or sensitivity level is displayed in analog form. A sensor sensitivity adjustment device comprising: a display section; and a sensitivity adjustment section that changes the sensitivity so that a value displayed by the display section falls within a predetermined range. (2) The display section is configured to display the input signal or sensitivity level in an analog manner, and to display a threshold mark when the displayed value matches a threshold value. A sensor sensitivity adjustment device according to claim 1. (3) The sensor sensitivity adjustment device according to claim 1 or 2, wherein the display section and the sensitivity adjustment section are configured to be remotely operated from outside the sensor. (4) Sensitivity adjustment of the sensor according to any one of claims 1 to 3, characterized in that the sensitivity adjustment section includes a storage means for storing a sensitivity level at the time of sensitivity adjustment. Device.