JPH02306107A - Distance sensor - Google Patents

Abstract

PURPOSE:To visually confirm the actual location of an object by displaying the size of a measuring voltage output from a measuring circuit corresponding to the distance to said object. CONSTITUTION:When a switch 80 is turned to an R side, a measuring voltage VR output from a measuring circuit 100 is input to a display circuit 120, so that the position of an object is displayed at 40. Then, a display element 51 of a mechanical indicator 50N is allowed to slide and set by the side of a light emitting element 41. When the switch 80 is switched to an N side, a set voltage VN output from a setting circuit 60 is input to the circuit 120, so that the size of the voltage VN is indicated by 40. At this time, since an intended setting position is indicated by 51, it is instantly found out from the relation between the intended setting position and the position of the element 41 whether the voltage VN is larger or smaller than an aiming value or how much the voltage VN is aside from the aiming value. As a variable resistor 61 is turned so that the display of the indicator 40 covers the position of the indicating element 51, the voltages VN and VR come to agree with each other, which is detected by a comparison circuit 130, with changing the state of an output displaying lamp 90. The resistor 61 is stopped to be turned.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention measures the distance to an object and outputs an analog output signal proportional to the distance, as well as outputs an on/off output signal by comparing it with a set value. The present invention relates to a distance sensor that also outputs a distance sensor.

[Prior Art] In recent years, for the purpose of achieving more optimal control in automatic control of FA (factory automation), etc., an intermediate between on/off switches such as photoelectric switches and proximity switches and high-grade digital distance sensors has been developed. There is an increasing demand for a distance sensor that can output an analog output signal proportional to the measured distance and an on/off output signal compared to a set value.

FIG. 6 schematically shows a conventional example of such a distance sensor.

This distance sensor 1 is an example of an optical distance sensor, in which light emitted from a light projector 2 is directed at an object, the reflected light is received by a light receiver 3, and the distance to the object is determined by triangulation. It measures the distance and outputs an analog output signal proportional to the distance.

Furthermore, in this example, two variable resistors 5 and 6 are used to set the detection position of the object both near and far, and when the object is within this limited range, an on/off output signal is output and the output indicator light 4 is turned on. I try to let them do it.

[Problem to be solved by the invention] Although such a distance sensor does not need to be as accurate as a digital sensor to determine where an object is actually located, it is possible to visually check in real time. If possible, it would be convenient for process control, etc., but there is a problem in that it is not possible with the conventional distance sensor l.

In addition, the detection position of the object is set by turning the variable resistor (usually a multi-rotation type variable resistor) 5.6, but until the output indicator light 4 lights up or goes out, the setting value does not change. There is a problem in that it is difficult to set the detection position because it is not known at all whether the transition is occurring or not.

Another problem is that the actual position of the object cannot be known at all in relation to the set value.

Therefore, the main object of the present invention is to provide a distance sensor that is improved in these respects.

[Means to solve the problem]

The distance sensor of the present invention includes a measurement circuit that measures the distance to an object and outputs an analog measurement voltage proportional to the distance, and a variable resistor that sets the detection position of the object. one or more setting circuits that generate set voltages of corresponding magnitudes, and a comparison that compares the magnitude of the measured voltage from the measuring circuit and the magnitude of each set voltage from the setting circuit, and outputs an on/off output signal. A circuit, an output indicator light that lights up in response to an on/off output signal from the comparator circuit, an indicator formed by arranging a plurality of light emitting elements in a row, and an indicator that can be slid along the indicator. a mechanical indicator that can be positioned at a position corresponding to each light emitting element of the indicator, and a display circuit that causes a predetermined one of the plurality of light emitting elements forming the indicator to emit light depending on the magnitude of an input voltage. and a changeover switch that selectively switches between the measured voltage from the measuring circuit and the set voltage from the setting circuit and inputs the same to the display circuit.

[Effect]

According to the above configuration, when the changeover switch is switched to the measurement circuit side, the measurement signal output from the measurement circuit is input to the display circuit, thereby displaying the position of the object on the display.

When the selector switch is switched to the desired setting circuit side, the setting voltage output from the setting circuit is input to the display circuit, and the setting position at that time is thereby displayed on the display.

Further, by sliding the indicator of the mechanical indicator, the set position can be mechanically memorized and displayed.

〔Example〕

FIG. 1 is a plan view showing the appearance of a distance sensor according to an embodiment of the present invention.

In this distance sensor 10, a main body case 2 houses an electric circuit (the details of which will be described later) as shown in FIG.
A display section 30 having the following configuration is provided on the top surface of the device.

That is, this display section 30 has a plurality of (10 in this example) light emitting elements (for example, light emitting diodes) 4 in its center.
1 is arranged in a row, and two mechanical indicators 5ON and 50F are provided on the left and right sides of it, and a changeover switch (in this example, 3
A point switching female switch) 80 and two variable resistors (in this example, multi-rotation type variable resistors) 61 and 71 are provided. Further, an output indicator light (for example, a light emitting diode) 90 is provided on the other side.

To explain the configuration of the mechanical indicators 5ON and 50F,
The display unit 30 has a display unit case 31 as shown in FIG. 2, and a row of rectangular window holes 34 for the light emitting elements 41 of the display unit 40 are provided in the center of the display unit case 31. The same number of round window holes 33 as the window holes 34 are provided at positions corresponding to each window hole 34 on the left and right sides of this row of window holes 34, and furthermore, there are elongated through grooves 32 on the outside of this row of window holes 33. are respectively provided, and between the rows of window holes 34 and the rows of window holes 33, wavy walls 35 are provided which form valleys at positions corresponding to the respective window holes 33.

As shown in FIG. 3, there is a knob 52 that fits into the through groove 32 of the display case 31, an elastic ring-shaped support 53, and a semicircular display that covers the window hole 33 of the display case 31. The two indicators 51 having portions 54 are
As shown in the figure and FIG.
It is mounted so that the head is exposed from 2 and the display part 54 is located on the back side of the window hole 33.

Therefore, each indicator 51 can be manually slid along the indicator 40 and positioned at a position corresponding to each light emitting element 41 of the indicator 40. At that time, the position of the indicator 51 is such that the indicator 54 is located at the window hole 33.
It can be clearly seen by exposing it. In this case, it is preferable that the color of the display section 540 is different from the color of the display section case 31.

In addition, 36 to 39 in the display part case 3 shown in FIG. 2 are for the changeover switch 80, for the variable resistor 61, and for the variable resistor 61, respectively.
This is a window hole for the variable resistor 71 and the output indicator light 90.

Next, the electric circuit of this distance sensor 10 will be explained with reference to FIG.

This distance sensor 10 is an example of a limited width detection type,
A measurement circuit 100 that measures the distance to an object using a triangulation method and outputs an analog measurement voltage VR proportional to the distance; an analog output circuit 110 that amplifies this measurement voltage VR and outputs an analog output signal SA; Setting circuits 60 and 70 that generate setting voltages VN and VF, respectively, the aforementioned changeover switch 80, and the aforementioned indicator 4 that detects the magnitude of the input analog voltage in 10 stages.
0 light emitting element 41 at a position corresponding to the input voltage, a display circuit 120 that causes the light emitting element 41 at a position corresponding to the input voltage to emit light, a comparison circuit 130 that compares the measured voltage ■R with the set voltages VN and VF, and outputs an on/off output signal SO, and the above-mentioned Output indicator light 90
It is equipped with

The measurement circuit 100 includes a light projection circuit 101 that emits pulsed light based on a signal from an oscillation circuit 1102, and a position detection element (PSD), which receives reflected light from an object and detects the position of the object. A light receiving circuit 103 that outputs a signal, an amplifier circuit 104 that amplifies this signal, and an analog measurement voltage V proportional to the distance to the object based on this signal.
There is an arithmetic circuit 105 that outputs R.

The setting circuit 60 sets the detection position nearer to the object (NEAR), and includes the aforementioned variable resistor 61 for setting and a voltage that generates a set voltage VN of a magnitude corresponding to its rotational position. It has a generating circuit 62.

The setting circuit 70 is for setting the farthest (FAR) detection position of the object, and includes the aforementioned variable resistor 71 for setting and a set voltage V having a magnitude corresponding to its rotational position.
It has a voltage generation circuit 72 that generates F.

The comparison circuit 130 compares the measured voltage VR from the measurement circuit 100 with the set voltage VN from the setting circuit 60 and outputs a high level when VN≦VR. A comparator 132 that compares the voltage VR with the set voltage VF from the setting circuit 70 and outputs a high level when VR≦VF, and an AND circuit 1 that takes the logical product of the outputs of both comparators 131 and 132.
33, and this AND circuit 133 outputs an on/off output signal SO that becomes high level when the measured voltage VR is within a limited range of VN≦VR:VF.

Note that an output mode switching circuit including a changeover switch, a NOT circuit, etc. may be provided within this comparison circuit 130 or on its output side. 140 in FIG. 1 is a mode changeover switch in such a case.

Measured voltage from measurement circuit lOO VR1 Setting voltage VN from setting circuit 60 and Setting voltage VF from setting circuit 70
are respectively input to the R contact, N contact, and F contact of the changeover switch 80, and are selectively switched and input to the display circuit 120 by switching the changeover switch 80. Therefore, the display 40 shows the reality of the object (REAL).
), the nearer detection position set by the variable resistor 61, and the farther detection position set by the variable resistor 71 are switched and displayed.

Next, the operation of the distance sensor 10 will be explained according to an example of a setting procedure.

First, as shown in FIG. 5, the distance sensor 10 is set at a predetermined position.

When setting the closest detection position among the two desired detection positions, the object 150 is placed at that position as shown by the two-dot chain line.

Next, when the changeover switch 80 is set to the R side, the measurement voltage VR output from the measurement circuit 100 is displayed on the display circuit 120.
is input, and the position of the target object 150 is displayed on the display 40. That is, a predetermined light emitting element 41 of the display 40 emits light.

Since this position is the closest detection position, the indicator 51 of the mechanical indicator 5ON is slid and set next to the light emitting element 41 that has emitted light.

Next, when the changeover switch 80 is switched to the N side, the setting voltage VN output from the setting circuit 60 is input to the display circuit 120, and the magnitude of the setting voltage VN at that time is displayed on the display 40.
will be displayed.

At this time, since the target setting position is displayed by the indicator 51, depending on the relationship between that position and the position of the light emitting element 41 that is currently emitting light, the current setting voltage VN is above or below the target value. You can see at a glance what distance it is and how far away it is. Therefore, the setting becomes very easy.

Then, as the variable resistor 61 is rotated so that the display on the display 40 matches the position of the indicator 51, the set voltage VN and the measured voltage VR eventually become -I, which is detected by the comparator circuit 130. and the state of the output indicator lamp 90 changes. Therefore, the rotation of the variable resistor 61 is stopped at that point.

For example, if you increase the set voltage VN from below the target value (the position of the indicator 51), when the two match, the output indicator light 9
0 goes off, and conversely, when the two match, the output indicator light 90 lights up (at this time, the comparator 132
output is always at high level).

This completes the setting of the closer detection position.

The setting of the farthest detection position is also performed in the same manner as above.

That is, as shown by the solid line in FIG. 5, the object 150 is placed at the farthest detection position.

Next, when the changeover switch 80 is set to the R side, the measurement voltage VR output from the measurement circuit 100 is displayed on the display circuit 120.
is input, and the position of the target object 150 is displayed on the display 40. That is, a predetermined light emitting element 41 of the display 40 emits light.

Since that position is the farthest detection position, the indicator 51 of the mechanical indicator 50F is slid and set next to the light emitting element 41 that has emitted light.

Next, when the changeover switch 80 is switched to the F side, the set voltage VF output from the setting circuit 70 is input to the display circuit 120, and the magnitude of the set voltage VF at that time is displayed on the display 40.
will be displayed.

At this time, the target position is also displayed on the indicator 51, so depending on the relationship between that position and the position of the light emitting element 41 that is currently emitting light, the current set voltage VF is above or below the target value. You can see at a glance what distance it is and how far away it is.

Therefore, the setting becomes very easy.

Then, as the variable resistor 71 is rotated so that the display on the display 40 matches the position of the indicator 51, the set voltage VF and the measured voltage VR eventually match, and this is detected by the comparison circuit 130. The state of the output indicator light 90 changes. Therefore, the rotation of the variable resistor 71 is stopped at that point.

For example, when the set voltage VF is increased from below the target value (the position of the indicator 51), when the two match, the output indicator light 9
0 lights up, and conversely, if you lower it from the top, the output indicator light 90 goes out when the two match (at this time, the comparator 131
The output of the target object 150 is always at a high level because it is located further away than the nearby detection position).

With the above steps, the setting of the two detection positions has been completed, so after that, it is only necessary to return the changeover switch 80 to the R side and enter the measurement state.

In the measurement state, the actual position of the object is displayed on the display 40, and it is also displayed on the mechanical indicators 5ON and 50F.
The relationship between the actual position of the object and the preset detection range can be seen at a glance in relation to the position of the indicator 51.

Then, when the object comes within the detection range, in this example, the comparison circuit 130 outputs a high-level on/off output signal SO, and the output indicator light 90 also lights up.

Although the above distance sensor 10 is an example of an integrated type, it may be a separate type in which the light emitting circuit 101, the light receiving circuit 103, and the accompanying first stage amplifier in the measuring circuit 100 are separated as a sensor head.

Further, by moving the setting circuits 60 and 70 to the outside of the main body case 20 or providing them both inside and outside the main body case 20, remote setting becomes possible.

Further, the distance sensor 10 described above is an example in which two detection positions of the target object are set, but of course it is also possible to set one or three or more detection positions of the target object. In that case, the number of mechanical indicators, the number of setting circuits, the number of switching points of the changeover switch, the number of comparators included in the comparison circuit, etc. may be adjusted according to the number of settings.

Further, the measurement circuit 100 in the distance sensor 10 is an optical type, but instead, it may be an ultrasonic type that measures the distance to an object using ultrasonic waves, or an ultrasonic type that measures the distance to a metal object using electromagnetic coupling. An electromagnetic type or the like may also be used.

〔Effect of the invention〕

As described above, according to the present invention, the magnitude of the measured voltage output from the measurement circuit according to the distance to the target object can be displayed on the display, so the actual position of the target object can be visually confirmed in real time. can do.

In addition, when setting the detection position of an object, the target setting position can be displayed on the mechanical display, and the current setting value of the variable resistor can be displayed on the display, so both can be used. The relationship between the two can be seen at a glance, and therefore the detection position can be set very easily.

In addition, after setting the detection position, the set position is displayed on the mechanical display, and the actual position of the object can be displayed on the display, so it is possible to You will be able to see at a glance where your actual location is.

[Brief explanation of drawings]

FIG. 1 is a plan view showing the appearance of a distance sensor according to an embodiment of the present invention. 2 is an enlarged back view of the display case of FIG. 1. FIG. FIG. 3 shows the indicator shown in FIG. 1, with (A) being a plan view thereof and (B) being a right side view thereof. FIG. 4 is a block diagram showing an example of an electric circuit of the distance sensor shown in FIG. 1. FIG. 5 is a schematic diagram for explaining the setting procedure of the distance sensor shown in FIG. 1. FIG. 6 is a schematic perspective view showing an example of a conventional distance sensor. DESCRIPTION OF SYMBOLS 10... Distance sensor according to the example, 40... Display device, 41... Light emitting element, 5ON, 50F... Mechanical indicator, 51... Indicator, 60.70... Setting circuit,
61.71... Variable resistor, 80... Changeover switch, 90... Output indicator light, 100... Measurement circuit, 12
0...display circuit, 130...comparison circuit.

Claims (1)

[Claims] (1) It has a measurement circuit that measures the distance to the object and outputs an analog measurement voltage proportional to the distance, and a variable resistor that sets the detection position of the object, and the size corresponds to the rotational position. one or more setting circuits that generate set voltages; a comparison circuit that compares the magnitude of the measured voltage from the measuring circuit with the magnitude of each set voltage from the setting circuit and outputs an on/off output signal; It has an output indicator light that lights up in response to an on/off output signal from a comparator circuit, an indicator consisting of a plurality of light emitting elements arranged in a row, and an indicator that can be slid along this indicator. a mechanical indicator that can be positioned at a position corresponding to each light emitting element;
A display circuit that causes a predetermined one of a plurality of light emitting elements constituting the display to emit light according to the magnitude of an input voltage, and a measurement voltage from the measurement circuit and a set voltage from the setting circuit are selected. A distance sensor characterized by comprising a changeover switch that selectively switches and inputs input to a display circuit.