JP2007170986A - Contact type displacement gauge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a contact type displacement gauge that has a simple constitution and can obtain a stable measured value. <P>SOLUTION: A CPU receives a timing signal from an external device such as a PLC at a time t1. In response to it, the CPU generates a timing trigger. Timing trigger generated in response to a timing signal provided from the outside is called an external timing trigger. Next, the CPU starts measurement (sampling) at a time t2 when a delay time ΔT preset by a user elapses from the external timing trigger. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a contact displacement meter that measures the amount of displacement of an object.

  The contact-type displacement meter has a contactor (movable part) and a transformer that are in contact with the surface of an object and can be displaced in the axial direction (see, for example, Patent Document 1).

  The transformer includes a core that interlocks with the contact. When the core is displaced according to the displacement of the contact, the level of the signal output from the transformer changes in accordance with the displacement of the contact. In such a configuration, the physical displacement amount such as the height of the target object is measured by converting the physical displacement amount of the target object into an electric quantity.

A contact displacement meter generally includes a head portion including a transformer and a main body portion that controls the head portion (see, for example, Patent Document 2). An external signal is input to the main body from an external device such as a PLC (programmable logic controller). Thereby, the physical displacement amount of the object is measured at the input timing of the external signal.
Japanese Patent Laid-Open No. 2000-9412 JP 2002-131037 A

  However, in a contact displacement meter, since the contact of the head part can be freely displaced in the axial direction, the measurement value is often not stable due to the influence of vibration or the like.

  Therefore, the time is managed by a PLC timer, and the external signal is given to the main body of the contact displacement meter at a predetermined timing. However, even in this case, strict time management may be difficult.

  An object of the present invention is to provide a contact displacement meter that can acquire a stable measurement value with a simple configuration.

  A contact displacement meter according to the present invention is a contact displacement meter that measures a physical displacement amount of an object, and a contactor that is displaced by contact with the object, and the displacement amount of the contactor as an electrical signal. Conversion means for conversion, setting means for setting a delay time for starting measurement, and obtained by the conversion means when a delay time set by the setting means has elapsed from the generation of a trigger for instructing measurement Acquisition means for acquiring an electric signal as a measured value of the displacement amount.

  In the contact displacement meter according to the present invention, the contact is displaced by contacting the object. The displacement amount of the contact is converted into an electric signal by the converting means. The delay time for starting measurement is set by the setting means. Furthermore, when the delay time set by the setting unit has elapsed from the generation of the trigger for instructing the measurement, the electrical signal obtained by the conversion unit is acquired by the acquisition unit as a displacement measurement value.

  With such a configuration, it is not necessary to perform time management of trigger generation for instructing measurement. In addition, a stable measurement value can be obtained with a simple configuration in which the delay time for starting measurement is set by the setting means.

  Furthermore, even when there is a case where it is desired to change the timing for acquiring the measurement value due to various circumstances, the delay time can be easily and arbitrarily changed by the setting means.

  The contact displacement meter may further include an external trigger input unit that receives a signal supplied from an external device as a trigger.

  In this case, when the delay time set by the setting means elapses from the time when the signal given from the external device is received as a trigger by the external trigger input means, the electrical signal obtained by the conversion means is a measured value of the displacement amount. Is acquired by the acquisition means. Thereby, even when a signal is given as a trigger from an external device at an arbitrary timing, a stable measurement value can be acquired.

  The contact displacement meter may further include an internal trigger generating means for generating a trigger when the level of the electrical signal obtained by the converting means reaches a predetermined threshold value.

  In this case, when the level of the electric signal obtained by the conversion means reaches a predetermined threshold value, a trigger for instructing measurement is generated by the internal trigger generation means. With such a configuration, it is possible to reliably acquire a stable measurement value and improve the reliability of the acquired measurement value.

  The contact displacement meter may further include a first display unit that displays the measurement value acquired by the acquisition unit.

  In this case, the user can grasp | ascertain the exact displacement amount of a target object easily by visually recognizing a 1st display means.

  The contact displacement meter may further include second display means for displaying whether or not the measurement value acquired by the acquisition means is within a predetermined range.

  In this case, the user can easily grasp whether or not the amount of displacement of the object is within a predetermined range by visually recognizing the second display means.

  According to the contact displacement meter according to the present invention, it is not necessary to perform time management of generation of a trigger for instructing measurement. In addition, a stable measurement value can be obtained with a simple configuration in which the delay time for starting measurement is set by the setting means. Furthermore, even when there is a case where it is desired to change the timing for acquiring the measurement value due to various circumstances, the delay time can be easily and arbitrarily changed by the setting means.

  Hereinafter, a contact displacement meter according to an embodiment of the present invention will be described with reference to the drawings.

(1) Overall Configuration of Contact Displacement Meter FIG. 1 is a block diagram showing the configuration of the contact displacement meter according to the present embodiment.

  As shown in FIG. 1, a contact displacement meter 100 according to the present embodiment includes a head portion 100A and a main body portion 100B. Although not shown in FIG. 1, the main body unit 100B includes a display unit 32 described later. Details of the display unit 32 will be described later.

  The head portion 100A and the main body portion 100B are connected to each other by a cable 80. The main body 100B is connected to an external device (not shown) via a cable 81.

  2 is a block diagram showing a configuration of the head unit 100A of FIG. 1, and FIG. 3 is a block diagram showing a configuration of the main body unit 100B of FIG.

  As shown in FIG. 2, the head unit 100A includes a transformer 1, a contact 1a that can be expanded and contracted and is in contact with an object, a transformer drive circuit 2, a signal detection circuit 3, an amplifier circuit 4, an EEPROM (Electrically Erasable and Programmable Read). Only Memory) 5, indicator lamp control circuit 6, indicator lamp 7, power supply circuit 8, comparator 9, and switch 10.

  As shown in FIG. 3, the main body 100B includes a CPU 20, a PWM (pulse width modulation) output circuit 21, a first filter circuit 22, a second filter circuit 23, and an A / D (analog / digital) converter. 24, communication interface 25, power supply circuit 26, drive circuit 27, first to third input circuits 28a, 28b, 28c, overcurrent detection circuit 29, first to third output circuits 30a, 30b, 30c, EEPROM 31, A display unit 32, a display panel 33, an input unit 34, and a connection unit 50 are provided.

  Signals are transmitted and received between the head unit 100A and the main body unit 100B via the cable 80. In this case, the cable 80 connected to the head unit 100A is connected to the connection unit 50 of the main body unit 100B.

  In FIG. 3, first, the CPU 20 gives a rectangular wave pulse signal for operating the transformer 1 to the PWM output circuit 21. The PWM output circuit 21 converts the rectangular wave pulse signal into a sine wave signal. The first filter circuit 22 removes noise from the sine wave signal and supplies the sine wave signal to the transformer drive circuit 2 in FIG.

  The transformer drive circuit 2 applies a sine wave current to the transformer 1 in response to the sine wave signal. Details of the configuration and operation of the transformer 1 will be described later.

  Subsequently, the transformer 1 supplies two voltage signals (described later) to the signal detection circuit 3. The signal detection circuit 3 subtracts the two voltage signals from each other and gives a differential voltage to the amplifier circuit 4.

  The amplifier circuit 4 performs impedance conversion and supplies a differential voltage to the second filter circuit 23 (FIG. 3). The second filter circuit 23 converts the differential voltage into a DC voltage and supplies the DC voltage to the A / D converter 24.

  The A / D converter 24 converts the DC voltage into a digital value, and gives the conversion result to the CPU 20 as a measured value of the physical displacement. The CPU 20 controls the display unit 32, the drive circuit 27, and the like based on the given measurement value.

  Signals are transmitted / received to / from an external device such as a main body of another contact displacement meter, a personal computer, or a PLC (programmable logic controller) (each not shown) via the communication interface 25 of the main body 100B. be able to. For example, when it is desired to import information related to the main body 100B into the PLC, information is transmitted to and received from the PLC via the communication interface 25.

  The power supply circuit 26 of the main body 100B is connected to an external DC power supply (not shown) of 24V, for example, and supplies power to each component of the head 100A via the power supply circuit 8 of the head 100A and the main body 100B. Electric power is supplied to each of the components.

  The drive circuit 27 supplies a current required for turning on or blinking the indicator lamp 7 of the head unit 100 </ b> A to the indicator lamp control circuit 6 via the switch 10.

  Here, the CPU 20 can switch the voltage level of the power supply circuit 8 of the head portion 100A via the power supply circuit 26 of the main body portion 100B. This voltage level includes, for example, 8.5 V in the communication mode performed at startup and 6.5 V in the normal operation mode.

  The communication mode is a mode in which the CPU 20 receives correction information stored in the EEPROM 5 of the head unit 100A, and the normal operation mode is a display that is performed when the CPU 20 controls the indicator lamp control circuit 6 of the head unit 100A. A mode in which the lamp 7 is turned on or blinked. The correction information stored in the EEPROM 5 will be described later.

  The comparator 9 of the head unit 100A connects the switch 10 to the EEPROM 5 side when the voltage level is 8.5 V based on the switching of the voltage level of the power supply circuit 8 by the CPU 20. On the other hand, the comparator 9 connects the switch 10 to the indicator light control circuit 6 side when the voltage level is 6.5V. With this configuration, the contact displacement meter 100 can be switched between the communication mode and the normal operation mode.

  The first to third input circuits 28a, 28b, 28c give the CPU 20 predetermined signals input from the outside. The predetermined signal is, for example, a timing signal for instructing the start of measurement, a preset signal for setting a reference position, or the like.

  The first to third output circuits 30a, 30b, and 30c are allowed by the CPU 20 including the physical displacement amount of the object obtained in accordance with the differential voltage from the head unit 100A and preset upper and lower limits. Based on the range, signals can be output to the outside.

  Specifically, for example, the first output circuit 30a determines a predetermined level (“H” level or “L” level) when the physical displacement amount of the object exceeds the upper limit value of the allowable range. Output a signal. The second output circuit 30b outputs a determination signal of a predetermined level (“H” level or “L” level) when the physical displacement amount of the object is below the lower limit value of the allowable range. Furthermore, the third output circuit 30c outputs a determination signal of a predetermined level (“H” level or “L” level) when the physical displacement amount of the object is within the allowable range.

  The overcurrent detection circuit 29 monitors whether or not a current equal to or higher than the rated current value flows through the first to third output circuits 30a, 30b, and 30c. When a current equal to or higher than the rated current value flows in any of the first to third output circuits 30a, 30b, and 30c, the overcurrent detection circuit 29 temporarily turns the output circuit off. Thereafter, the CPU 20 periodically turns on the output circuit, and the overcurrent detection circuit 29 continues to monitor the output circuit.

  The EEPROM 31 of the main body 100B stores correction information. This correction information will be described later.

  The display unit 32 displays the amount of physical displacement of the object under the control of the CPU 20. The display unit 32 includes a display panel 33 and an input unit 34. Details of the display panel 33 and the input unit 34 will be described later with reference to the drawings. The reset circuit 35 resets the CPU 20 to an initial state by giving a reset signal to the CPU 20 based on a user's operation.

  Here, when the frequency of use of the contact 1a is increased, the head unit 100A often fails. In such a case, the main body 100B is used as it is, and the head 100A is replaced with a new one.

  First, a new head portion 100A (hereinafter simply referred to as the head portion 100A) is attached to the main body portion 100B. The CPU 20 of the main body 100B communicates with the EEPROM 5 of the head 100A in the communication mode.

  The EEPROM 5 stores correction information of the head unit 100A (hereinafter referred to as head correction information) and correction information of an inspection master main body (to be described later) (hereinafter referred to as master correction information).

  The head correction information is information for correcting variation in the relationship between the physical displacement amount of the object and the output value from the A / D converter 24 of the main body 100B (hereinafter referred to as a displacement-output table). is there.

  The master correction information is information for correcting variation in the displacement-output table of the inspection master body used for obtaining the head correction information.

  The CPU 20 communicates with the EEPROM 5 to acquire the master correction information. Next, the CPU 20 communicates with the EEPROM 31 of the main body 100B.

  The EEPROM 31 stores correction information of the main body 100B (hereinafter referred to as main body correction information).

  The main body correction information is information for correcting variations in the relationship between the level of the DC voltage converted by the second filter circuit 23 of the main body 100B and the output value from the A / D converter 24.

  The CPU 20 communicates with the EEPROM 31 to acquire the main body correction information. Then, based on the acquired main body correction information and master correction information, the CPU 20 uses the same state as the state in which the reference master body for inspection is used, that is, from the output value of the A / D converter 24, the object. Create a state that can recognize the exact amount of physical displacement.

  Thereafter, the CPU 20 communicates with the EEPROM 5 to acquire the head correction information, thereby accurately determining the relationship between the DC voltage level of the second filter circuit 23 and the output value of the A / D converter 24. Create a recognizable state. Thereby, even when the head portion 100A is replaced, the main body portion 100B can be brought into the same state as the master main body portion serving as a reference, and an appropriate physical displacement amount of the object can be obtained.

(2) Configuration of Transformer Next, a detailed configuration of the transformer 1 of the head unit 100A will be described with reference to the drawings.

  FIG. 4 is a schematic diagram showing a detailed configuration of the transformer 1.

  As shown in FIG. 4, the transformer 1 includes a primary coil 1b, a secondary coil 1c, a primary resistor 1d, a secondary resistor 1e, and a core C made of a magnetic material. The core C is provided so as to be capable of reciprocating in the primary side coil 1b and the secondary side coil 1c in conjunction with the contact 1a.

  One end of the primary side coil 1 b is connected to the transformer drive circuit 2, and the other end is connected to the signal detection circuit 3. One end of the secondary coil 1 c is grounded, and the other end is connected to the signal detection circuit 3. The winding directions of the primary coil 1b and the secondary coil 1c are opposite to each other.

  One end of the primary side resistor 1d is connected to the node N1 between the primary side coil 1b and the signal detection circuit 3, and the other end is grounded. One end of the secondary side resistor 1e is connected to the node N2 between the secondary side coil 1c and the signal detection circuit 3, and the other end is grounded.

  In such a configuration, when a sine wave current flows from the transformer drive circuit 2 to the primary side coil 1b, an induced current flows to the secondary side coil 1c accordingly. In this case, a voltage drop occurs in the primary resistor 1d and a voltage drop also occurs in the secondary resistor 1e. The voltage of the node N1 at one end of the primary side resistor 1d and the voltage of the node N2 at one end of the secondary side resistor 1e are supplied to the signal detection circuit 3.

  As described above, when the core C is moved in a state where the induced current flows through the secondary coil 1c, the mutual inductance between the primary coil 1b and the secondary coil 1c changes. Thereby, the voltage of the node N2 changes depending on the position of the core C.

  The signal detection circuit 3 calculates a differential voltage between the voltage at the node N1 and the voltage at the node N2, and applies the differential voltage to the amplifier circuit 4. With such a configuration, the amount of physical displacement of the object can be detected by converting the amount of movement of the contact 1a into a differential voltage.

  In the present embodiment, the winding direction of the primary side coil 1b and the secondary side coil 1c is opposite, so that the resistance components of the primary side coil 1b and the secondary side coil cancel each other. Thus, by canceling out the resistance component having a characteristic that varies depending on the temperature, the accurate differential voltage can be obtained without being affected by the temperature change at the place where the contact displacement meter 100 is used. As a result, an accurate physical displacement amount of the object can be obtained.

(3) Measurement (Sampling) Method Next, a method for measuring a physical displacement amount of an object using the contact displacement meter 100 of the present embodiment will be described.

  FIG. 5 is an explanatory diagram for explaining a method of measuring a physical displacement amount of an object.

  5A, 5B, and 5C, the horizontal axis represents time, and the vertical axis represents the physical displacement of the object (hereinafter referred to as a measured value). The CPU 20 has a timer function for measuring the delay time ΔT.

  As shown in FIG. 5A, first, the CPU 20 receives a timing signal at an instant t1 from an external device such as a PLC. Thereby, the CPU 20 generates a timing trigger. A timing trigger generated in response to an externally applied timing signal is called an external timing trigger.

  Next, the CPU 20 starts measurement (sampling) at a time point t2 when a delay time ΔT preset by the user has elapsed from the external timing trigger. This eliminates the need for the user to strictly manage the appropriate input timing of the timing signal from the outside, and does not acquire unstable measurement values due to vibrations of the contact 1a. As a result, an accurate measurement value can be acquired. In this case, the CPU 20 regards the measurement value acquired after the time t2 as an effective measurement value, and whether the effective measurement value is within the predetermined allowable range, exceeds the upper limit value of the allowable range, and the allowable range. Judge whether it is below the lower limit of.

  Further, the user can set a desired delay time ΔT by using an input unit 34 described later of the main body 100B. Thereby, the user can set an arbitrary optimum measurement start timing. Furthermore, even if it is necessary to change the measurement start timing due to various circumstances, the user can easily change the delay time ΔT by the input unit 34.

  Here, the measured value becomes unstable after the contact 1a of the contact displacement meter 100 comes into contact with the object.

  Therefore, in the present embodiment, as shown in FIG. 5B, not only the setting of the delay time ΔT but also the determination that the contact 1a has started to rise due to contact with the object is made. Is set in advance by the input unit 34 as the trigger level L1.

A timing trigger is generated at time t3 when the measured value reaches a preset trigger level L1. A timing trigger generated with reference to the trigger level L1 is referred to as an internal timing trigger. Starting from this internal timing trigger, measurement starts at time t4 when a separately set delay time ΔT has elapsed. Thereby, since CPU20 can set delay time (DELTA) T from the time t3 when the contact 1a contacted the target object, it can obtain a more exact measured value. In this case, the CPU 20 regards the measurement value acquired after time t4 as an effective measurement value, and whether the effective measurement value is within a predetermined allowable range, exceeds the upper limit value of the allowable range, and the allowable range. Further, in FIG. 5C, a timing trigger is generated at time t5 when the measured value falls below a preset trigger level L2, as in FIG. 5B. . A timing trigger generated with reference to the trigger level L2 is referred to as an internal timing trigger as described above. Starting from this internal timing trigger, measurement starts at time t6 when a separately set delay time ΔT has elapsed. In this case, the CPU 20 regards the measurement value acquired after time t6 as an effective measurement value, and whether the effective measurement value is within a predetermined allowable range, exceeds the upper limit value of the allowable range, and the allowable range. Next, the processing of the CPU 20 when the delay time ΔT is not provided and the processing of the CPU 20 when the delay time ΔT is provided will be described.

  FIG. 6 is a flowchart showing processing by the CPU 20 when the delay time ΔT is not provided.

  As shown in FIG. 6, first, the CPU 20 determines whether or not a measurement start timing signal is given from an external device such as a PLC (step S1).

  When the timing signal is given, the CPU 20 acquires a measured value (step S2). Thereafter, the CPU 20 returns to the process of step S1, and repeats the processes of step S1 and step S2.

  In step S1, when the timing signal is not given, the CPU 20 waits until the timing signal is given.

  FIG. 7 is a flowchart showing processing by the CPU 20 when the delay time ΔT is provided.

  As shown in FIG. 7, first, the CPU 20 determines whether or not a measurement start timing signal is given from an external device such as a PLC (step S11). When the timing signal is not given, the CPU 20 waits until the timing signal is given.

  When the timing signal is given, the CPU 20 generates an external timing trigger and starts measuring the elapsed time by the built-in timer (step S12).

  Next, the CPU 20 determines whether or not the elapsed time has reached a preset delay time ΔT (step S13). When the elapsed time has not reached the delay time ΔT, the CPU 20 waits until the elapsed time reaches the delay time ΔT.

  When the elapsed time reaches the delay time ΔT, the CPU 20 acquires the measurement value as an effective measurement value (step S14). Thereafter, the CPU 20 returns to the process of step S11 and repeats the processes of steps S11 to S14.

  FIG. 8 is a flowchart illustrating another example of processing performed by the CPU 20 when the delay time ΔT is provided. The example of FIG. 8 is a case where the delay time ΔT is provided and the trigger level L1 or the trigger level L2 is also set.

  As shown in FIG. 8, first, the CPU 20 determines whether or not a measurement start timing signal is given from an external device such as a PLC (step S21). When the timing signal is not given, the CPU 20 waits until the timing signal is given.

  When the timing signal is given, the CPU 20 determines whether or not the measured value exceeds the trigger level L1 or whether or not the measured value falls below the trigger level L2 (step S22). If the measured value does not exceed the trigger level L1, or if the measured value does not fall below the trigger level L2, the CPU 20 waits until the measured value exceeds the trigger level L1 or until the measured value falls below the trigger level L2.

  When the measured value exceeds the trigger level L1, or when the measured value falls below the trigger level L2, the CPU 20 generates an internal timing trigger and starts measuring the elapsed time with the built-in timer (step S23).

  Next, the CPU 20 determines whether or not the elapsed time has reached a preset delay time ΔT (step S24). When the elapsed time has not reached the delay time ΔT, the CPU 20 waits until the elapsed time reaches the delay time ΔT.

  When the elapsed time reaches the delay time ΔT, the CPU 20 acquires the measurement value as an effective measurement value (step S25). Thereafter, the CPU 20 returns to the process of step S21 and repeats the processes of steps S21 to S25.

(4) Configuration of Display Unit Next, the configuration of the display unit 32 of the main body unit 100B will be described with reference to the drawings.

  FIG. 9 is a schematic diagram illustrating a configuration of the display unit 32 of the main body 100B.

  As shown in FIG. 9, the display unit 32 of the main body unit 100 </ b> B includes a display panel 33 and an input unit 34.

  The display panel 33 includes three output indicator lamps 41, a 7 segment LED (light emitting diode) 42, and a bar display unit 43. The input unit 34 includes a mode key 44, a set key 45, and a cross key 46.

  The user can shift from the normal mode to the setting mode by pressing the mode key 44 for 3 seconds or more in the normal mode for displaying the measured values and the like, and can display the setting menu on the 7-segment LED 42. .

  Further, the user can change the setting item of the setting menu by operating the cross key 46 left and right, and can change the value of the setting item by operating the cross key 46 up and down. Further, the user can determine the value of the setting item by pressing the set key 45. The setting items include the delay time ΔT, the trigger levels L1 and L2, the upper limit value and the lower limit value for determining the allowable range.

  The 7-segment LED 42 displays the measured value of the object, and one of the output indicator lamps 41 is lit (HI lit) when the measured value exceeds the upper limit value. One is lit when the measured value is within the allowable range (GO lit), and the other one of the output indicator lights 41 is lit when the measured value is below the lower limit (LO lit). To do.

  The bar display unit 43 displays the position of the measured value within the allowable range with a plurality of bars. Thereby, the user can easily recognize whether the measured value is near the lower limit value or the upper limit value, or whether the measured value has a margin for the lower limit value or the upper limit value within the allowable range. It becomes possible.

(5) Effects in the present embodiment Conventionally, the measured value becomes unstable after the contact of the contact displacement meter contacts the object, so that the timing signal is calculated by estimating the time when the measured value is stabilized. The timing to be given was managed by an external device such as a PLC. However, it may be difficult to perform time management strictly with an external device, and as a result, accurate measurement values may not be obtained.

  In the contact displacement meter 100 according to the present embodiment, an arbitrary delay time ΔT is set in advance by the user, and after a timing signal is given from an external device, an effective measurement value is obtained when the delay time ΔT elapses. Acquisition starts. With such a configuration, the external device does not need to manage the timing at which the timing signal is applied, and the contact displacement meter 100 can acquire a stabilized measurement value.

  Further, even when there is a case where it is desired to change the timing for acquiring the measurement value due to various circumstances, the user can arbitrarily change the delay time ΔT with an easy and simple configuration by using the input unit 34 of the main body 100B. it can.

  Furthermore, in the contact displacement meter 100 of the present embodiment, trigger levels L1 and L2 can be provided in order to reliably determine that the contact 1a of the contact displacement meter 100 has contacted the object. Then, after the measured value exceeds the trigger level L1 or after the measured value falls below the trigger level L2, acquisition of the measured value is started when a preset delay time ΔT has elapsed. Thereby, the measured value stabilized reliably can be acquired.

(6) Other Embodiments In the above embodiment, an example in which a timing signal for starting measurement is given from an external device such as a PLC has been described. However, the present invention is not limited to this example. A timing signal may be generated.

(7) Correspondence between each component of claim and each part of embodiment The following describes an example of the correspondence between each component of the claim and each part of the embodiment. It is not limited.

  In the above embodiment, the transformer 1 corresponds to the conversion means, the input unit 34 corresponds to the setting means, the CPU 20 corresponds to the acquisition means, the external trigger input means, and the internal trigger generation means, and the 7-segment LED 42 is the first. The bar display unit 43 corresponds to the second display unit.

  The contact displacement meter according to the present invention can be used to detect the physical displacement of an object.

It is a block diagram which shows the structure of the contact-type displacement meter which concerns on this Embodiment. It is a block diagram which shows the structure of the head part of FIG. It is a block diagram which shows the structure of the main-body part of FIG. It is a schematic diagram which shows the detailed structure of a transformer. It is explanatory drawing for demonstrating the measuring method of the physical displacement amount of a target object. It is a flowchart which shows the process by CPU when not providing delay time. It is a flowchart which shows the process by CPU when providing delay time. It is a flowchart which shows the other example of the process by CPU in the case of providing delay time. It is a schematic diagram which shows the structure of the display part of a main-body part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transformer 1a Contact 2 Transformer drive circuit 3 Signal detection circuit 4 Amplifier circuit 5 EEPROM
6 Indicator lamp control circuit 7 Indicator lamp 8 Power supply circuit 9 Comparator 20 CPU
DESCRIPTION OF SYMBOLS 21 PWM output circuit 22 1st filter circuit 23 2nd filter circuit 24 A / D converter 25 Communication interface 28a, 28b, 28c 1st-3rd input circuit 29 Overcurrent detection circuit 30a, 30b, 30c 1st ~ Third output circuit 31 EEPROM
32 Display 33 Display Panel 34 Input 41 Output Indicator 42 7 Segment LED
43 Bar display section 44 Mode key 45 Set key 46 Cross key 50 Connection section 80 Cable 100 Contact displacement meter 100A Head section 100B Main section C Core L1, L2 Trigger level t1 to t6 Time point ΔT Delay time

Claims (5)

A contact displacement meter that measures the physical displacement of an object,
A contact that is displaced by contact with an object;
Conversion means for converting the displacement of the contact into an electrical signal;
A setting means for setting a delay time for starting measurement;
And an acquisition means for acquiring an electrical signal obtained by the conversion means as a measured value of the displacement when a delay time set by the setting means has elapsed since generation of a trigger for instructing measurement. Contact displacement meter. 2. The contact displacement meter according to claim 1, further comprising external trigger input means for receiving a signal given from an external device as the trigger. 3. The contact type according to claim 1, further comprising an internal trigger generating means for generating the trigger when the level of the electrical signal obtained by the converting means reaches a predetermined threshold value. Displacement meter. The contact-type displacement meter according to claim 1, further comprising a first display unit that displays a measurement value acquired by the acquisition unit. The contact according to claim 1, further comprising second display means for displaying whether or not the measurement value acquired by the acquisition means is within a predetermined range. Displacement meter.

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