JP2011033450A - Detection sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detection sensor preventing worker's false recognition. <P>SOLUTION: A CPU is switchably equipped with: a normal display function for displaying a signal level (average value MA) of an output signal in a second display section; and a focus function for displaying an adjustment value AD obtained by multiplying the signal level of an output signal by a focus magnification Fx at the second display section. The CPU is set to be in a display mode for normally displaying the average value MA at the second display section in the normal display function, and is set to be in a display mode for alternately displaying the adjustment value AD and a character string "Foc" at the second display section in the focus function. When a worker selects either one of the normal display function and the focus display function, the CPU displays the signal level of an output signal in either display mode by the selected display function. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a detection sensor for detecting an object to be detected.

  For example, a detection sensor such as a photoelectric sensor receives light projected from a light projecting element by a light receiving element, and receives light based on a threshold level set for a change in the amount of received light depending on the presence or absence of an object to be detected (work). The detected object is detected (for example, refer to Patent Document 1).

  The detection sensor of Patent Document 1 has a display function (scaling function) that appropriately enlarges and adjusts the detection value obtained by the light receiving unit and displays the adjusted value as a display value on the display unit. This display function, for example, multiplies the detection value obtained for the purpose of making the display value easy to see at a predetermined magnification when displaying the detection value obtained by the light receiving element.

JP 2007-158641 A

  By the way, in the detection sensor having the display function as described above, when the display function is used, the display value after adjustment displayed on the display unit changes more than the change amount of the detection value obtained by the light receiving element. Therefore, workers who are aware that they are using the display function feel that there is no problem with the change in the display value after the adjustment, but they are not aware that the display function is being used. An operator may feel uncomfortable with the change in the display value after the adjustment, and may erroneously recognize that the detection sensor has failed.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a detection sensor capable of preventing erroneous recognition by an operator.

  In order to solve the above-mentioned problem, the invention according to claim 1 is characterized in that a detection means for outputting a detection signal corresponding to a detection state of an object to be detected, and a signal level of the detection signal obtained by the detection means. A detection sensor comprising display means capable of displaying and control means for displaying the signal level of the detection signal on the display means, wherein the control means displays the signal level of the detection signal on the display means. And a second display function for causing the display means to display a signal level after the calculation of the signal level of the detection signal at a predetermined magnification, and a display mode by the first display function The display function is set to be different from the display mode by the second display function, and is selected by the function selection means capable of selecting one of the first display function and the second display function. , And its gist that for displaying the signal level on the display means.

  In this invention, the control means has a first display function for displaying the signal level of the output signal on the display means, and a second display function for displaying the calculation result obtained by calculating the output signal level at a predetermined magnification on the display means. Provided to be switchable. The display mode by the first display function is set to be different from the display mode by the second display function, and when one of the first display function and the second display function is selected by the selection means, the selected one is selected. The signal level is displayed on the display means by the control means by the display function. As described above, since the display modes of the first display function and the second display function are configured to be different, when the signal level is displayed on the display means by any one of the display functions, On the other hand, since it is possible to notify which display function is selected depending on the display mode of each display function, it is possible to suppress erroneous recognition by the user such as a detection sensor failure.

  According to a second aspect of the present invention, in the detection sensor according to the first aspect, the signal level in the detection state and the signal level in the non-detection state of the detected object detected by the detection means are set in advance. The gist of the invention is that it includes magnification setting means for setting the magnification in the second display function based on the ratio to the target value.

  In the present invention, the magnification in the second display function is set based on the ratio between the signal level in the detection state and the signal level in the non-detection state of the detected object detected by the detection means, and a preset target value. A magnification setting means is provided. Even in such a configuration, since the display mode of the first display function is different from the display mode of the second display function, the same effect as in the first aspect can be obtained.

  According to a third aspect of the present invention, in the detection sensor according to the second aspect of the present invention, when the magnification of the second display function exceeds a reference level, an abnormality determination unit that determines and reports an abnormality is provided. Is the gist.

  In this invention, when the magnification in the second display function exceeds the reference level, an abnormality determining unit that determines and reports an abnormality is provided. As described above, when the magnification exceeds the reference level by the abnormality determination unit, the magnification in the second display function can be guided to the reference level or less by being notified by display / sound or the like.

  According to a fourth aspect of the present invention, in the detection sensor according to the second or third aspect of the present invention, the detection unit includes a changing unit capable of changing the target value, and the magnification setting unit changes the target value by the changing unit. In this case, the gist is to reset the magnification in the second display function.

  In the present invention, there is provided changing means capable of changing the target value, and when the target value is changed by the changing means, the magnification in the second display function is reset by the magnification setting means. As described above, by providing the changing means that can change the target value by the user and resetting the magnification when the target value is changed by the changing means, the magnification in the second display function can be adjusted. . Therefore, for example, when the magnification in the second display function exceeds the reference level and the fact is notified as in the configuration described in claim 3, the target value is reset and the magnification is adjusted to the reference level or less. be able to.

  According to a fifth aspect of the present invention, in the detection sensor according to any one of the second to fourth aspects, the control means is configured such that when the second display function is selected by the function selection means, The gist of the present invention is to display the calculated signal level calculated with the magnification in the second display function and the magnification on the display means.

  In this invention, when the second display function is selected by the function selection means, the control means displays the signal level after the calculation calculated by the magnification in the second display function and the magnification in the second display function. Displayed on the means. In this way, when the second display function is selected, the signal level after calculation calculated by the magnification in the second display function and the magnification are displayed on the display means, so that the user can perform the calculation after the calculation. It is possible to notify how much the signal level has been changed from the original signal level.

  Therefore, according to the above described invention, it is possible to provide a detection sensor capable of preventing erroneous recognition by an operator.

The top view of the fiber sensor in this embodiment. The block diagram which shows the electrical constitution of a fiber sensor. (A) (b) (c) is explanatory drawing which shows the hierarchical structure of a function. 7 is a flowchart for explaining an example of a setting operation for focus magnification. 6 is a flowchart for explaining an example of an operation when a focus function is selected.

Hereinafter, an embodiment in which the present invention is embodied in a fiber sensor will be described with reference to the drawings.
As shown in FIG. 1, the sensor body 11 of the fiber sensor 10 is formed in a substantially rectangular parallelepiped shape, and a digital display unit 12 as display means capable of, for example, 8-digit digital display is provided on the upper surface thereof. On the front end side (left side in FIG. 1) of the digital display unit 12, an operation indicator lamp 13 is provided as a leaving means made of, for example, an LED (light emitting diode).

  In addition, the digital display unit 12 displays a plurality of functions (for example, setting of a threshold level and fine adjustment thereof) and various setting values provided in the fiber sensor 10. The digital display unit 12 includes a first display unit 14 including four 7-segment LEDs 14a to 14d for displaying four digits and a second display unit 15 including four 7-segment LEDs 15a to 15d for displaying four digits. It is connected.

  A pair of triangular selection switches 16 and 17 are provided on the upper surface of the sensor body 11 on the base end side (right side in FIG. 1) of the digital display unit 12. A square-shaped determination switch 18 is provided on the side opposite to the display unit 12 (right side in FIG. 1).

  The selection switches 16 and 17 are used for switching the functions displayed on the digital display unit 12 by the respective pressing operations in the order opposite to each other. The determination switch 18 is displayed on the digital display unit 12 by the pressing operation. This is for determining the current function to be displayed.

As shown in FIG. 2 , the fiber sensor 10 includes a light projecting circuit 22 including a light projecting element 21, a light receiving circuit 24 serving as a detecting unit including a light receiving element 23, and a CPU 25 constituting a control unit. Yes. The CPU 25 is provided with a memory 26 and a timer 27 as storage means. The light projecting circuit 22 receives the output signal from the CPU 25 and causes the light projecting element 21 to emit light with a predetermined light amount. The emitted light is photoelectrically converted by the light receiving element 23 and input to the light receiving circuit 24, and an output signal having a level corresponding to the amount of light received by the light receiving element 23 is output to the CPU 25.

  In the sensor body 11 shown in FIG. 1, light projecting fibers 28 and light receiving fibers 29 shown in FIG. 2 are provided on both sides of the transport path (in the direction of the white arrow in FIG. 2) of the object W to be transported sequentially. It is arranged. Further, the light projecting fiber 28 and the light receiving fiber 29 are arranged so that their tips are opposed to each other in the vertical direction of the transport path. Then, the amount of light received by the light receiving element 23 (detection value) that changes depending on the amount of the object to be detected W entering the optical path (detection region) between the light projecting element 21 and the light receiving element 23 formed via both fibers 28 and 29. ) Is output from the light receiving circuit 24 to the CPU 25.

  The CPU 25 calculates a moving average value MA of the received light signal level at a plurality of (for example, three) measurement points obtained by sampling the output signal, and compares the average value MA with the threshold level. Then, the CPU 25 outputs a detection signal that is inverted according to the comparison result between the average value and the threshold level to the output circuit 30 and lights the operation indicator lamp 13 in red, for example.

  The CPU 25 is electrically connected to a display circuit 31 constituting control means. The CPU 25 drives the 7-segment LEDs 14 a to 14 d and 15 a to 15 d of the digital display unit 12 via the display circuit 31 to the digital display unit 12. Display letters, numbers and symbols. Further, a switch input circuit 32 is electrically connected to the CPU 25. The CPU 25 detects the operations of the selection switches 16, 17 and the determination switch 18 via the switch input circuit 32, and the selection switches 16, 17 and the determination switch are detected. The display on the digital display unit 12 is controlled in accordance with the operation 18.

  The functions displayed on the digital display unit 12 are grouped in a related manner, and are classified into a two-layered structure of upper layer (upper layer), middle layer (middle layer), and lower layer (lower layer). Each function can be executed by operating the selection switches 16 and 17 and the decision switch 18.

  Specifically, as shown in FIG. 3A, the upper layer includes “RUN (normal detection state in which the detection operation of the object W is detected)”, “TEACH (threshold level setting)”, “L / D ON (light-on / non-light-on setting), TIMER (timer operation setting), CUST (custom setting contents display), and PRO (detailed setting) functions are classified. Has been.

  In addition, each function of “PRO1” to “PRO5” is classified in the middle layer, which is one layer lower than the upper layer “PRO”. In addition, each function corresponding to “Pro1” to “Pro5” is classified in the lower layer, which is one layer lower than the middle layer.

  The fiber sensor 10 of the present embodiment includes a normal display function as a first display function for displaying the average value MA on the second display unit 15 and a predetermined magnification (focus magnification described later) with respect to the average value MA. Fx) and a focus function as a second display function for displaying the adjusted adjustment value AD on the second display unit 15. In particular, the selection of each function or the like is performed by the middle-layer function “PRO2 (focus function setting)”, and the lower layer, which is one level lower than the function “PRO2”, is shown in FIG. “SET (target value setting during focus function)”, “DTCH (focus magnification processing)”, and “FSEL (focus function selection)” are classified.

  In a state where the detection object W is detected, the threshold level is displayed on the first display unit 14 and the received light signal level is displayed on the second display unit 15. At this time, the determination switch 18 is pressed. When operated, the upper layer function “RUN” is displayed on the first four-digit first display portion 14 of the digital display portion 12. In this state, for example, when the selection switch 16 is pressed, as shown in FIG. 3A, the upper layer function displayed on the first display unit 14 changes “RUN” → “ It is switched to a loop in the order of “TEACH” → “L / D ON” → “TIMER” → “CUST” → “PRO” → “RUN”. When the selection switch 17 is operated, the upper layer functions displayed on the first display unit 14 according to the number of operations are looped in the reverse order to the case where the selection switch 16 is pressed. Can be switched.

  Further, for example, the determination switch 18 is pressed in a state where one of the upper layer functions “RUN”, “TEACH”, “L / D ON”, “TIMER”, and “CUST” is displayed on the first display unit 14. Then, processing related to the function is allowed. In addition, when the determination switch 18 is pressed while the upper layer function “PRO” is displayed on the first display unit 14, as shown in FIG. 3B, it is displayed on the first display unit 14. Is switched to the function “Pro1” in the middle layer, which is a lower layer. In this state, for example, when the selection switch 16 is pressed, the functions of the middle layer displayed on the first display unit 14 are “Pro1” → “Pro2” → “Pro3” → “ The loop is switched in the order of “Pro4” → “Pro5” → “Pro1”. When the selection switch 17 is pressed, the functions of the middle layer displayed on the first display unit 14 according to the number of operations are looped in the reverse order to the case where the selection switch 16 is pressed. Can be switched to.

  For example, when the determination switch 18 is pressed in a state where the middle layer function “Pro2” is displayed on the first display unit 14, the function displayed on the first display unit 14 is a lower layer that is one level lower. Is switched to the function “SET”. In this state, for example, when the selection switch 16 is pressed, the lower layer functions displayed on the first display unit 14 change “SET” → “DTCH” → “FSEL” → “ It is switched to a loop in the order of “SET”. When the selection switch 17 is pressed, the functions of the middle layer displayed on the first display unit 14 according to the number of operations are looped in the reverse order to the case where the selection switch 16 is pressed. Can be switched to.

  At the time of the focus function, the first target value T1 that is the display upper limit value on the second display unit 15 is set to the maximum value (for example, 4096) displayed on the second display unit 15, and is stored in the memory 26 of the CPU 25 in advance. It is remembered. The second target value T2 that is the display lower limit value in the second display unit 15 is set to the minimum value (for example, 0) displayed on the second display unit 15 and is stored in the memory 26 of the CPU 25 in advance. However, these target values T1 and T2 may be configured to be arbitrarily changeable by the operator. For example, when the determination switch 18 is pressed while the lower layer function “SET” is displayed, The first target value T1 is switched to a settable state. In this state, when the first target value T1 is set by the operator and the determination switch 18 is pressed, the second target value T2 is switched to a settable state. In this state, when the second target value T2 is input by the operator and the determination switch 18 is pressed, “SET” is displayed on the first display unit 14, and the target value is set when the focus function is selected. Complete.

  When the determination switch 18 is pressed while the lower layer function “DTCH” is displayed on the first display unit 14, the display magnification setting operation in the focus function is performed by the CPU 25 as shown in FIG. 4. It is supposed to be executed.

  The CPU 25 controls the light projecting element 21 and the light receiving element 23 via the light projecting circuit 22 and the light receiving circuit 24, and acquires, for example, a received light amount (hereinafter referred to as a first acquired value) G1 in a state where there is no object to be detected W. (Step S10), the acquired first acquisition value G1 is stored in, for example, the memory 26 (Step S20). Next, when the determination switch 18 is pressed, a received light amount (hereinafter referred to as a second acquired value) G2 in a state where the object W is present is acquired (step S30), and the acquired second acquired value G2 is stored in the memory. 26 (step S40). Thereafter, the CPU 25 calculates the focus magnification Fx when the focus function is selected as shown in Expression 1 (step S50). When the focus magnification Fx is set, for example, if the magnification exceeds a reference level, the CPU 25 displays “hard” on the second display unit 15 via the display circuit 31, for example.

そして、ＣＰＵ２５は、上記式１にて求めたフォーカス倍率Ｆｘが基準レベル以下であればその倍率Ｆｘをメモリ２６に記憶し（ステップＳ６０）、その後第１表示部には「ＤＴＣＨ」が表示され、フォーカス倍率Ｆｘの設定が終了する。

Then, the CPU 25 stores the magnification Fx in the memory 26 if the focus magnification Fx obtained by the above equation 1 is equal to or lower than the reference level (step S60), and then “DTCH” is displayed on the first display unit. The setting of the focus magnification Fx is completed.

  Here, the memory 26 is configured by a nonvolatile memory. For example, when the power of the sensor 10 is turned off and then turned on again, the focus magnification Fx is stored as it is. That is, as long as the focus magnification Fx is not changed, the value of the focus magnification Fx is configured to be constant.

  Further, when the determination switch 18 is pressed while the lower layer function “FSEL” is displayed on the first display unit 14, “on” or “off” is displayed on the second display unit 15, and the selection is made. When the switches 16 and 17 are pressed, the character string displayed on the second display unit 15 is switched between “on” and “off”.

  When the determination switch 18 is pressed in a state where “on” is displayed on the second display unit 15, the CPU 25 executes various operations with the focus function enabled when the upper layer function “RUN” is executed. . When the focus function is selected and the focus magnification Fx is not set (function “DTCH”), “Err” is displayed on the second display unit 15, and the operator is informed. Inform the effect.

  In addition, when the determination switch 18 is pressed in a state in which “off” is displayed on the second display unit 15, the CPU 25 disables the focus function, that is, selects the normal display function when executing the upper layer function “RUN”. As a result, various operations are executed.

(Select focus function)
Next, an operation example of the fiber sensor 10 when the focus function (second display function) is selected using the focus magnification Fx set as described above will be described with reference to FIG.

  When the determination switch 18 is pressed while the upper layer function “RUN” is displayed, the CPU 25 starts detecting the detection target W. Then, as described above, an output signal of a level corresponding to the amount of light received by the light receiving element 23 is input to the CPU 25 via the light receiving circuit 24, and the CPU 25 outputs an output signal input to the CPU 25 as shown in FIG. The moving average value MA of the received light signal level at a plurality of (for example, three) measurement points sampled is calculated, and this average value (current value) MA is obtained (step S100).

  Next, the CPU 25 reads the second acquired value G2 in the state with the detected object W acquired by the function “DTCH” from the memory 26 (step S110), and divides the second acquired value G2 from the average value MA. A difference D1 between the average value MA and the second acquired value G2 is calculated (step S120).

  Then, the CPU 25 multiplies the difference D1 calculated in step S120 by the focus magnification Fx set by the function “DTCH” (step S130), and adds the second target value T2 to the multiplied value. The adjustment value AD is calculated by offsetting at (step S140). As described above, the first target value T1 is set in advance to the display upper limit value (4096) displayed on the second display unit 15, and the second target value is displayed in advance on the second display unit 15. Since (0) is set, the upper limit of the adjustment value AD can be adjusted to be the display upper limit value, and the lower limit of the adjustment value AD can be adjusted to be the display lower limit value, and can be displayed.

  Then, the CPU 25 controls the display circuit 31 to alternately display the character string “Foc” and the adjustment value AD on the second display unit 15 (step S150). The CPU 25 controls the display circuit 31 to display the threshold level on the first display unit 14. Then, the CPU 25 operates to repeat steps S100 to S160.

(Normal display function selection)
On the other hand, when the above-described focus function is disabled, that is, when the normal display function is selected, the CPU 25 controls the display circuit 31 to display the average value MA of the output signal output from the light receiving circuit 24 to the CPU 25 on the second display unit 15. Let Further, the CPU 25 controls the display circuit 31 to display the threshold level on the first display unit 14.

  In the fiber sensor 10 as the detection sensor configured as described above, when the normal display function is selected, the average value MA as the signal level is displayed on the second display unit 15, and when the focus function is selected, The fact that the focus function (first display function) has been selected is displayed on the second display unit 15 with the character string “Foc” and the adjustment value AD as the signal level. In this way, it is possible to notify the operator of which display function is selected by changing the display mode depending on the display function. Thus, it is possible to suppress misrecognition by the operator.

Next, characteristic effects of the present embodiment will be described.
(1) The CPU 25 as the control means has a normal display function as a first display function for displaying a light reception signal level (average value MA) as a signal level of the output signal on the second display unit 15, and a light reception signal level. A focus function as a second display function for displaying the adjustment value AD, which is a calculation result multiplied by a predetermined magnification (focus magnification Fx), on the second display unit 15 is switchable. The CPU 25 is set so that the average value MA is always displayed as it is on the second display unit 15 in the normal display function, and the adjustment value AD and the character string “Foc” are alternately displayed on the second display unit 15 in the focus function. The display mode is set to be displayed. When either one of the normal display function and the focus display function is selected by the operator, the CPU 25 displays the selected display function (always displaying the average value MA or alternately displaying the adjustment value AD and the character string “Foc”). The received light signal level is displayed in any of the display modes. As described above, since the display modes of the normal display function and the focus function are configured differently, when the signal level of the output signal is displayed on the second display unit 15 by any one of the display functions, Since the operator can be notified of which display function is selected depending on the display mode of each display function, it is possible to suppress erroneous recognition by the user by the user such as a detection sensor failure. it can.

  (2) The first target value T1 is set in advance as the display upper limit value (4096) displayed on the second display unit 15, and the second target value is displayed in advance on the second display unit 15 (display lower limit value ( 0). For this reason, the upper limit of the adjustment value AD can be adjusted to be the display upper limit value, and the lower limit of the adjustment value AD can be adjusted to be the display lower limit value. In this case, in the conventional detection sensor, when an operator who does not know whether or not the focus function is selected looks at the adjustment value as described above, there is a risk of erroneously recognizing that the signal level is saturated. However, for example, the configuration in which the adjustment value and the character string “Foc” are alternately displayed on the second display unit 15 as in the present embodiment can prevent erroneous recognition as described above.

  (3) A CPU 25 is provided as an abnormality determining means for determining that an abnormality has occurred and notifying when the focus magnification Fx during the focus function exceeds a reference level. As described above, when the magnification Fx exceeds the reference level, the CPU 25 can notify the second display unit 15 by displaying “hard”, thereby inducing the magnification Fx in the focus function below the reference level. it can.

  (4) The CPU 25 is provided with a function “SET” as changing means capable of changing the target values T1, T2, and when the target values T1, T2 are changed by the function “SET”, the magnification setting means The magnification Fx in the focus function is reset. As described above, the function “SET” that allows the user to change the target values T1 and T2 is provided, and the magnification Fx is reset when the target values T1 and T2 are changed by the function. Fx can be adjusted. For this reason, when the magnification Fx in the focus function exceeds the reference level and the fact is notified, the target values T1 and T2 can be reset to adjust the magnification Fx below the reference level.

  (5) Since the memory 26 is composed of a non-volatile memory, the set value is prevented from being lost by turning off the power of the sensor 10 (power off). Therefore, it is not necessary to set the focus magnification Fx every time when the power is turned on again (power is turned on), so that the work amount of the worker can be reduced.

In addition, you may change embodiment of this invention as follows.
In the above embodiment, the character string “Foc” is displayed on the second display unit 15 when the focus function is valid (selected). However, the present invention is not limited to this.

  For example, when the normal display function is selected in which the threshold level of the first display unit 14 is not displayed and the focus function is disabled, the character string “no” is displayed on the first display unit 14 and the second display unit 15 displays The average value MA is displayed. When the focus function is valid (selected), the character string “Foc” is displayed on the first display unit 14 and the adjustment value AD obtained by multiplying the average value MA by the focus magnification Fx is displayed on the second display unit 15. It is good also as a simple structure.

  Although not particularly mentioned in the above embodiment, the light emission color of the digital display unit 12 (second display unit 15) may be switched between when the focus function is selected and when the normal display function is selected.

  Further, for example, the average value MA displayed on the second display unit 15 is lit on when the normal display function is selected, and the adjustment value AD displayed on the second display unit 15 is blinked when the focus function is selected. May be.

  Further, when the focus function is selected, an adjustment value AD that is a signal level calculated using the focus magnification Fx and the focus magnification Fx may be alternately displayed on the second display unit 15, for example. As described above, when the focus function is selected, the adjustment value AD that is the signal level after the calculation with the magnification in the focus function and the magnification Fx are displayed on the second display unit 15, so that the user can On the other hand, it is possible to notify how much the calculated signal level (adjustment value AD) has been changed from the original signal level (average value MA) at what magnification Fx. In addition to the configuration of the above embodiment, the configuration may be such that the magnification Fx is displayed on the first display unit 14 or a display unit provided separately.

  In the above embodiment, when the function focus magnification Fx exceeds the reference level, “hard” is displayed on the second display unit 15 and the notification is made. Good.

  In the above embodiment, the first target value T1 and the second target value T2 can be changed by the function “SET” of the CPU 25. However, the present invention is not limited to this. A configuration using only the values T1 and T2, that is, a configuration in which the target values T1 and T2 cannot be changed may be used.

  In the above embodiment, the memory 26 is configured by a nonvolatile memory, but may be configured by a volatile memory. Even when the volatile memory is used, the focus magnification Fx can be maintained in the memory by supplying power to the memory.

  In the above embodiment, the digital display unit 12 is configured by using a plurality of 7-segment LEDs (a total of 8), but the present invention is not limited to this, and the digital display unit 12 may be a matrix display device. Alternatively, another display device such as an LCD (liquid crystal display device) may be used instead of the LED (light emitting diode).

  In the above embodiment, a so-called transmission type fiber sensor in which the light projecting element 21 and the light receiving element 23 are arranged to face each other is used. However, the present invention is not limited to this. You may comprise with what is called a reflection mirror type fiber sensor comprised with the reflection mirror arranged facing a unit. Further, a so-called reflection type fiber sensor that includes the light projecting / receiving unit and detects the presence / absence of the detection target W using reflected light from the detection target W may be used.

  In the above embodiment, the present invention is embodied in the fiber sensor, but is not limited thereto, and may be embodied in other detection sensors.

  DESCRIPTION OF SYMBOLS 10 ... Fiber sensor (detection sensor), 12 ... Digital display part (display means), 15 ... 2nd display part (display means and abnormal leaving means), 16, 17 ... Selection switch (function selection means), 18 ... Determination switch (Function selection means) 23... Light receiving element (detection means) 24... Light reception circuit (detection means), 25... CPU (control means, function selection means, magnification setting means and change means), Fx. ... Target value, W ... Detected object.

Claims (5)

Detection means for outputting a detection signal corresponding to the detection state of the detected object;
Display means capable of displaying the signal level of the detection signal obtained by the detection means;
Control means for displaying the signal level of the detection signal on the display means;
A detection sensor comprising:
The control means includes
A first display function for causing the display means to display the signal level of the detection signal; and a second display function for causing the display means to display a calculated signal level obtained by calculating the signal level of the detection signal at a predetermined magnification. As well as
The display mode by the first display function is set to be different from the display mode by the second display function,
A detection sensor characterized in that the signal level is displayed on the display means by a display function selected by a function selection means capable of selecting one of the first display function and the second display function. . The detection sensor according to claim 1,
The magnification in the second display function is set based on the ratio between the signal level in the detection state of the detected object detected by the detection means and the signal level in the non-detection state and a preset target value. A detection sensor comprising a magnification setting means. The detection sensor according to claim 2,
A detection sensor comprising abnormality determination means for determining that an abnormality has occurred and notifying when the magnification in the second display function exceeds a reference level. The detection sensor according to claim 2 or 3,
A changing means capable of changing the target value;
The detection sensor, wherein the magnification setting unit resets the magnification in the second display function when the target value is changed by the changing unit. In the detection sensor as described in any one of Claims 2-4,
When the second display function is selected by the function selection unit, the control unit uses the display unit to display the calculated signal level calculated by the magnification in the second display function and the magnification. A detection sensor characterized by being displayed.

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