JP2553688B2 - Multiple point simultaneous measurement system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a multipoint simultaneous measurement system for transmitting a plurality of measurement values measured by a plurality of transmitter-equipped measuring instruments from the same measuring instrument to a host system. In particular, the present invention relates to a multiple point simultaneous measurement system that transmits a plurality of measurement values in a time division manner using the same transmission means such as the same frequency band.

[Conventional technology]

For example, set the small moving distance of the measured
A dial gauge as shown in FIG. 12, for example, is known as one of portable displacement measuring instruments that can accurately measure up to a unit of 1 mm. Among the displacement measuring instruments 1 represented by such a dial gauge, there is an instrument that digitally displays the movement distance of the contactor 2 from the reference position on the display unit 3 as shown in the figure. Further, as a means for converting the moving distance of the contactor 2 into an electric signal, there is a means for detecting the amount of change in the oscillation frequency. For example, a core member is attached to the shaft supporting the contactor 2, and the core member is wound. As described above, a pair of coils is provided, and each coil is used to form a Colpitts-type oscillator, and a change in the oscillation frequency f of the oscillator caused by the movement of the core member interlocking with the contactor 2 in the pair of coils. The moving distance of the core member, that is, the moving distance of the contactor 2 is digitally calculated from the amount and digitally displayed on the display unit.

In such a manual displacement measuring instrument 1 which is operated by a manual operation, in order to efficiently process data of the measured moving distance, a microminiature transmitter is incorporated in the displacement measuring device itself to measure the moving distance. There is an attempt to wirelessly output the signal to an external host system, but in this case, a plurality of portable displacement measuring instruments 1 are often used, and when outputting wirelessly, the frequency band used by the transmitter of each displacement measuring instrument 1 is set. They are individually assigned to prevent mutual transmission of transmission data.

[Problems to be Solved by the Invention]

However, when the individual frequency is used for each transmitter as described above, there are the following problems.

(1) Management for using a plurality of radio frequency bands in one system becomes complicated.

(2) Since the host system receives a plurality of radio frequency bands, the mechanism of the receiver is complicated and expensive.

(3) In the unlikely event that one of the multiple devices fails, the transmitter and receiver that use other frequency bands cannot be used as alternative devices because the frequency bands are different.

(4) Since different frequency bands are used, the number of frequency bands that can be used is limited, and many measuring devices cannot be used at the same time.

In order to eliminate the above-mentioned conventional drawbacks, the present invention provides a multiple point simultaneous measurement system that uses a single frequency band and can time-divisionally transmit measured values from a plurality of measuring instruments. To aim.

[Means for solving the problem]

In order to achieve the above object, a multipoint simultaneous measurement system according to the present invention includes a synchronization signal output unit that outputs a synchronization signal, a measurement unit that measures an object to be measured and outputs a measurement value, and transmission for performing time division. A plurality of transmitters including a transmission time difference setting unit that sets a time difference, an arithmetic control unit that outputs the measurement value based on the transmission time difference and the synchronization signal, and a transmission unit that transmits the measurement value output by the arithmetic control unit Attached measuring instrument and a host system for processing the measuring instrument from the plurality of transmitter-equipped measuring instruments, and the transmission time setting unit sets a time for outputting a measured value after a predetermined time from the synchronization signal. The configuration includes a first setting unit and a second setting unit that sets the output interval of the measurement value, and is a means for solving the problem.

[Work]

In the multipoint simultaneous measurement system of the present invention, the transmission time setting unit of each transmitter-equipped measuring instrument sets the transmission time difference based on the synchronization signal from the synchronization signal output unit so that the measured value transmission times do not match. The measuring unit measures the object to be measured and outputs the measured value to the arithmetic control unit. The arithmetic control unit outputs the measurement value input from the measurement unit to the transmission unit at a cycle determined based on the synchronization signal from the synchronization signal output unit and the transmission time difference set by the transmission time difference setting unit. The transmitter transmits this measurement value to the host system. The host system receives measured values sent from each measuring instrument with transmitter with a time lag between them and performs predetermined data processing.

The transmission time difference setting unit sets the time to output the measured value first after inputting the synchronization signal, sets the output interval for outputting each measured value, and transmits multiple measured values in a single frequency band. Perform.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a block diagram showing a schematic configuration of this embodiment. This block diagram is roughly divided into displacement measuring instrument with transmitter
31 and a synchronization signal output unit 32 that outputs a synchronization signal to a plurality of displacement measuring instruments with a transmitter 31 and a host system that wirelessly receives measured values from a plurality of displacement measuring instruments with a transmitter 31 and performs data processing. It is composed of 33. In FIG. 1, only one displacement measuring device 31 with a transmitter is shown, and the other displacement measuring device 31 with a transmitter is omitted.

FIG. 2 shows the appearance of the displacement measuring device 31 with a transmitter. The guide shaft is provided on the lower surface of the housing 11 formed in a substantially rectangular parallelepiped shape.
A contact 13 is attached via a 12 to the housing 11 so as to be movable up and down. Further, on the front surface of the housing 11, various function keys 14 such as mode switching and zero point adjustment, and a display 15 formed of a liquid crystal display device are attached.

Next, the configuration for converting the displacement of the contact 13 into an electric signal
Shown in the figure. A core member 17 is attached to the shaft of the contactor 13, and the vertical movement of the contactor 13 is the vertical movement of the core member 17. A primary coil 22 is wound around the center of the core member 17,
Secondary coils 23a and 23b are wound above and below the primary coil 22. The shaft of the contactor 13 is provided with a housing 11 via a coil spring.
It is fixed to the top plate of.

A circuit for converting vertical relative displacement between the core member 17 and the primary coil 22 and the secondary coils 23a, 23b into an electric signal is a well-known Colpitts type oscillation circuit indicated by reference numeral 16 in FIG. Between the emitter and the emitter, the resistor 21, the capacitors 19 and 20 connected in series are connected in parallel, and
The secondary coil 23a and the switch 24a are connected in parallel, the secondary coil 23b and the switch 24b are connected in parallel, and a coil circuit in which the primary coil 22 is further connected in series is further connected in parallel. The secondary coils 23a and 23b have the same impedance value. The Colpitts oscillator circuit 16 is connected to a counter 25 and counts the oscillation frequency of the Colpitts oscillator circuit 16. Further, in FIG. 1, reference numeral 26 is an arithmetic control unit, which calculates the displacement from the output of the counter 25 and outputs the displacement at a predetermined cycle. 27 is a cycle for alternately opening and closing the switches 24a, 24b of the secondary coils 23a, 23b
A measurement timer for setting T ₀ , and 28 is the arithmetic control unit 26
It is a transmission timer that sets a cycle for outputting the displacement calculated in step. Reference numeral 15 is a display for displaying the calculated displacement.
Reference numeral 29 denotes a keyboard, which is used for setting the measurement timer 27 and the transmission timer 28, and issuing commands to the arithmetic control unit 26. The keyboard 29 may be a pluggable type so that it can be removed after initial setting. By doing this,
One keyboard can be used for a plurality of displacement measuring devices 31 with transmitters. Further, the measurement timer 27 and the transmission timer 28 can be miniaturized by using the arithmetic control unit 26 and the one incorporated in one chip. Reference numeral 30 denotes a transmission unit that transmits the displacement measurement value output from the calculation control unit 26 in a predetermined cycle to the host system 33. The synchronization signal from the synchronization signal output unit 32 interrupts the CPU of the operation control unit 26, and the transmission method of the synchronization signal can be a wired system, a wireless system, an optical system, an ultrasonic system, or the like.

 Next, the operation will be described.

In FIG. 3, when the contact 13 is moved upward, the core member 17 moves toward the secondary coil 23a, and the primary coil 22
And the secondary coil 23a is tightly coupled. When the contact 13 is moved downward, the core member 17 moves the secondary coil 23
Move in the direction of b, on the contrary, the primary coil 22 and the secondary coil 23b
The bond between and becomes tight.

Therefore, when the core member 17 is located at the center position (reference position) of the primary coil 22, the switch 24a
The oscillation frequency f _A of the Colpitts oscillator circuit 16 when only the switch 24b is closed and the oscillation frequency f _B when only the switch 24b is closed match. Then, when the core member 17 is moved in either direction, a difference is generated between the oscillation frequencies f _A and f _B , and the frequency difference Δf (= f _A −f _B ) is from the reference position of the core member 17. Is a value corresponding to the movement amount D of. The relationship between the frequency difference Δf and the movement amount D is, for example, a substantially linear relationship as shown in FIG.

The oscillation frequencies f _A and f _B of the Colpitts oscillator 16 are counted by the counter 25, converted into digital values, and input to the next arithmetic control unit 26. The arithmetic control unit 26 is composed of, for example, a microcomputer, and has various input / output ports, ROM, RAM and the like built therein. Then, the arithmetic control unit 26 alternately opens and closes each switch 24a, 24b of the Colpitts type oscillation circuit 16 by a time interrupt signal input from the timer 27 at regular time intervals T _O, and is input from the counter 25. Based on the respective oscillation frequencies f _A and f _B , the contact 13
The moving distance D is calculated, displayed on the display 15, incorporated into a digital transmission format, and sent to the transmission unit 30 at a timing based on the synchronization signal from the transmission timer 28 and the synchronization signal output unit 32. The transmission unit 30 frequency-modulates (FS) the transmission format incorporating the input movement distance D.
K modulation) and output wirelessly. The radio wave wirelessly output from the transmitter 30 is received by the receiver of the host system 33, and the moving distance D is demodulated to the original digital value.

Next, Colpitts oscillator 16, counter 25, measurement timer
The operations of 27 and the arithmetic control unit 26 will be described.

When a time interrupt signal is input from the timer 27 at constant time intervals T _{O, the} arithmetic control unit 26 executes a measurement timer interrupt process according to the flowchart shown in FIG. When the flow chart is started, the open / closed state of the switch 24a of the Colpitts oscillator circuit 16 is examined. If the switch 24a is closed, the switch 24a is opened, and conversely, the switch 24b is closed and the counter 25 is reset. As a result, the Colpitts oscillator circuit
The oscillation frequency of 16 changes from f _A to f _B. The counter 25 starts counting the changed oscillation frequency f _B. The counter 25 terminates the counting operation of the oscillation frequency f _B after a predetermined time shorter than the constant time T _O has elapsed from the start of counting, and outputs the counted oscillation frequency f _B. On the other hand, if the switch 24a is opened, the switch 24b is opened, the switch 24a is closed, and the counter 25 is reset. As a result, the counter 25 starts counting the oscillation frequency f _A. Further, the arithmetic control unit 26 executes a calculation distance main routine of the movement distance D according to the flowchart of FIG. When the flow chart is started, various initial processes are executed, and then the oscillation frequency f from the counter 25 is set in S (step) 1.
Is input, switch 24 of Colpitts oscillator circuit 16
Determine the frequency type from the open / closed state of a. If the switch 24a is closed in S2, the input oscillation frequency is f _A , and therefore it is stored in the f _A buffer of the storage unit. Then, the process returns to S1 and waits for the next oscillation frequency input.

If the input of the transmission frequency is f _B in S2, the input value f _B
Is stored in the f _B buffer. Then, the oscillation frequencies f _A and f _B are read out from the buffers and the frequency difference Δf (f _A −
f _B ) is calculated. After that, the moving distance D is calculated using the conversion formula D = F (Δf). When the moving distance D is calculated, it is stored in the memory and then digitally displayed on the display unit 15, and the process returns to S1 of the flowchart again. FIG. 9 is a time chart showing this operation.

In FIG. 9, the oscillation frequency of the Colpitts type oscillation circuit 16 is switched to the frequencies f _A and f _{B at} constant time intervals T ₀ . As a result, the output of the counter 25 also changes alternately between f _A and f _B. The moving distance D is calculated for every 2T ₀ to the arithmetic control unit 26.

Next, the operation of outputting the moving distance D at the timing and cycle set by the keyboard 29 by the synchronizing signal from the synchronizing signal output signal section 32 and the interrupt signal from the transmission timer 28 will be described with reference to FIGS. 7 and 8. .

FIG. 7 is a flow chart of an interrupt process for starting the transmission timer 26 with a synchronization signal. In this flow chart, the delay counter value N is a value that activates the transmission timer 28 after the lapse of T ₁ time after the synchronization signal is input, and is the value input to the arithmetic control unit 26 by the keyboard 29. This T ₁ is also set to each of a plurality of other transmitter-equipped measuring devices 31, and all the measuring devices 31
Are time-divided so that the moving distance D is transmitted to the host system 33. The delay counter value N is read from the memory, 1 is subtracted, and the operation is repeated until N becomes 0. When N = 0, it means that the interrupt has been received by the synchronizing signal and T ₁ time has elapsed, so the transmission timer 28 is started and the process returns to the main routine.

Next, the interrupt processing by the transmission timer 28 will be described with reference to FIG. When the transmission timer 28 is activated in the flow chart of FIG. 7, an interrupt signal is generated every T ₂ hours. This T ₂ time may be the same value in each transmitter-equipped measuring device 31. When the interrupt signal is generated by the transmission timer 28, the measured value D is read from the memory, sent to the transmission unit 30, and the main routine is restored. FIG. 10 is a time chart of the operation described with reference to FIGS. 7 and 8 above, and shows a case where there are three transmitter-equipped measuring instruments 31, and NO1 to NO3 are numbers given to the respective measuring instruments 31. is there. In the diagram (a), NO1 activates the transmission timer 28 T ₁₁ hours after receiving the synchronization signal S, generates an interrupt signal at a cycle T ₂ , and outputs the measured values D ₁₁ , D ₁₂ , and D ₁₃ at T ₂ intervals. It is sent to the transmission unit 30. NO2 activates the transmission timer 28 T ₂₁ hours after receiving the synchronization signal S, and sends the measured values D ₂₁ , D ₂₂ , and D ₂₃ in the cycle T ₂ . NO3 is the measured value D ₃₁ hours after receiving the synchronization signal S.
₃₁ , D ₃₂ , D ₃₃ are transmitted in the cycle T ₂ . (B) drawing, which the transmission cycle of the measured value D shows a case where a 2T ₂ in NO2, NO1 and NO3 are the same as (a). In this way, by changing the set value with the keyboard 29, the transmission cycle of the measured value D can be changed.

In the embodiment described above, T ₁ is determined by software, but both T ₁ and T ₂ may be set by a timer. An example of this is shown in FIG. This operation will be described. The T ₁ timer is activated by the synchronizing signal and the T ₂ timer is activated T ₁ hours after receiving the synchronizing signal. T ₂ timer is a b-contact T ₂ connected to itself
Generates an interrupt signal in the T ₂ cycle. If a timer composed of TTLIC is used, the time for opening and closing will be extremely short.

〔The invention's effect〕

According to the present invention, it is possible to transmit a plurality of measurement values from a plurality of transmitter-equipped measuring instruments to a host system in a single frequency band, and yet, each measuring instrument, after a predetermined time from a synchronization signal,
Since the measured values can be transmitted at regular intervals, the measured values can be transmitted a plurality of times with one synchronization signal.
In addition, management is easier than when a separate frequency band is used for each measuring instrument, and failure of some measuring instruments does not affect others. Moreover, since the mechanism is simple, there is an effect that it can be provided at low cost.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of an embodiment of the present invention, FIG. 2 is an external view of a displacement measuring instrument with a transmitter, FIG. 3 is a diagram showing a principle of converting displacement into an electric signal, and FIG. The figure shows the relationship between the frequency difference and the movement amount, FIG. 5 is a flow chart showing the interruption processing by the measurement timer, FIG. 6 is the flow chart for calculating the movement amount from the frequency difference, and FIG. 7 is the interruption processing by the synchronization signal. 8 is a flowchart showing the interrupt processing by the transmission timer, FIG. 9 is a time chart showing the operation of FIG. 6, FIG. 10 is a time chart showing the operation of FIG. 7 and FIG. FIG. 11 is a diagram showing a method of determining a data transmission period by using two timers, and FIG. 12 is an external view showing a general displacement measuring device. 13 ... contactor, 15 ... indicator,
16 …… Colpitts type oscillator circuit, 17 …… Core member, 18 ……
Transistor, 22 ... Primary coil, 23a, 23b ... Secondary coil, 24a, 24b ... Switch, 25 ... Counter, 26 ......
Arithmetic control unit, 27 …… Measurement timer, 28 …… Send timer, 29
...... Keyboard, 30 …… Transmitter, 31 …… Displacement measuring device with transmitter, 32 …… Synchronous signal output, 33 …… Host system

Claims (1)

(57) [Claims] 1. A synchronization signal output section for outputting a synchronization signal, a measurement section for measuring an object to be measured and outputting a measured value, a transmission time setting section for setting a transmission time difference for performing time division, and the transmission time difference. A plurality of transmitter-equipped measuring instruments each including an arithmetic control unit that outputs the measured values based on the synchronization signal and a transmitter that transmits the measured values output by the arithmetic control unit, and the plurality of transmitter-equipped measuring instruments. A host system that processes measurements from
And the transmission time setting section includes a first setting means for setting a time for outputting the measurement value after a predetermined time from the synchronization signal, and a second setting means for setting an output interval of the measurement value. Characteristic multi-point simultaneous measurement system.