JPH076787B2 - Display value holding type measuring instrument - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a display value holding type measuring instrument, and more particularly to a transducer for converting displacement of a probe into an electric signal, a measuring circuit for processing the electric signal, and a display for displaying an output of the measuring circuit as a measured value. Display, hold switch, and hold the display value by operating the hold switch, or
The present invention relates to an improvement of a display value holding type measuring device having a command signal generating means for generating a command signal for releasing the signal and a control circuit capable of exchanging signals with an external data processing device by a detachable signal transmitting means.

[Prior art]

2. Description of the Related Art In recent years, measuring instruments, such as electronic digital calipers and electronic digital micrometer, which have a built-in electrostatic capacitance type or photoelectric type transducer and digitally display a measured value have become widespread. In such a measuring device, there is a display value hold function as an effective function when performing measurement in a posture in which the display unit cannot be directly seen. In addition, there is a measurement value output function for outputting data to an external data processing device such as a host computer in order to statistically process the measurement values. Hold switch 12 for controlling the hold function
And a data output switch 14 for controlling the data output
Are separately provided as shown in FIG. 5 for the case of the electronic digital caliper 10. That is, in FIG. 5, the hold switch 12 is installed near the display 16 of the measuring instrument main body, and the data output switch 14 is
It is provided on the plug 18 of the connector for interface with the external data processing device.

[Problems to be Solved by the Invention]

However, in the electronic measuring device, there is a demand to reduce the number of switches as much as possible. That is, the provision of the mechanical switch increases the cost, and the cost can be reduced by adopting a form in which the processing can be performed inside the integrated circuit as much as possible. A method of mechanically switching depending on the connection with the connector is also conceivable, but this causes a cost increase.
Further, as the technology advances, more new functions such as a data preset function are required, so that it is desirable to reduce the number of switches for realizing the conventional functions as much as possible.

[Object of the Invention]

The present invention has been made to solve the above-mentioned conventional problems, and reduces the number of switches by relating the presence / absence of connection of an external data processing device to the hold switch having a function of a data output switch. It is an object of the present invention to provide a display value holding type measuring instrument capable of performing the above.

[Means for solving problems]

The present invention provides a transducer for converting displacement of a measuring element into an electric signal, a measuring circuit for processing the electric signal, an indicator for displaying an output of the measuring circuit as a measured value, a hold switch, and a hold switch. A display value holding type measuring instrument having a command signal generating means for generating a command signal for holding or canceling a display value by an operation and a control circuit capable of exchanging signals with an external data processing device by a detachable signal transmitting means. , The control circuit holds or releases the display value of the display based on the command signal, and when the hold command signal is generated, when the data request signal from the external data processing device is received, the measured value information is output from the measurement circuit. Output to the external data processing device, and at the end of the output, the command signal generating means should be provided with a function to generate a reset signal. Accordingly, those who attain the aforementioned object.

[Action]

The present invention provides a transducer for converting displacement of a measuring element into an electric signal, a measuring circuit for processing the electric signal, an indicator for displaying an output of the measuring circuit as a measured value, a hold switch, and a hold switch. A display value holding type measuring instrument having a command signal generating means for generating a command signal for holding or canceling a display value by an operation and a control circuit capable of exchanging signals with an external data processing device by a detachable signal transmitting means. , The control circuit holds or releases the display value of the display based on the command signal, and when the hold command signal is generated, when the data request signal from the external data processing device is received, the measured value information is output from the measurement circuit. Is also provided with a function of outputting a data signal having an output to an external data processing device and generating a reset signal in the command signal generating means at the end of the output. It is. Therefore, the number of switches can be reduced by providing the hold switch with the function of the data output switch in association with the presence or absence of the connection of the external data processing device.

【Example】

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this embodiment, as shown in FIG. 1, a transducer 20 for converting displacement of a tracing stylus (not shown) into an electric signal, a measuring circuit 22 for processing the electric signal, and a display buffer 24 are used for input. A display device 26 for displaying the output of the measurement circuit 22 as a measured value, a hold switch 28, a JK flip-flop 38 for generating a command signal for holding the display value by operating the hold switch 28, or releasing the output, and an output. In the display value holding type measuring instrument having the control circuit 30 capable of signal exchange with the external data processing device 34 by the buffer 32 and the detachable connector 33, the control circuit 30 is provided with a display value of the display device 26 based on the command signal. Hold or release,
When a data request signal from the external data processing device 34 is received when the hold command signal is generated, the data signal DATA having the measurement value information is output from the measuring circuit 22 to the external data processing device 34, and at the end of the output, the JK flip-flop. 38 has a function of generating a reset signal. When the hold switch 28 is not connected to the external data processing device 34, the hold switch 28 is of a toggle operation system that repeats hold and hold release each time it is pressed and released, and is connected to the high level side of the power supply via the pull-up resistor 36. At the same time, it is connected to the control circuit 30 via the JK flip-flop 38. Since the JK terminal of this JK flip-flop 38 is not used, the output of the output terminal Q is inverted every time the negative hold signal H is input to the clock terminal CK. The output of the output terminal Q is logic 0 at the input of the reset terminal R.
(Inactive). In FIG. 1, 39 is a pull-up resistor. Next, the software configuration of the control circuit 30 will be described with reference to the flowchart of FIG. That is, in the control circuit 30, the JK flip-flop
When the interrupt signal I output from the output terminal Q of 38 becomes logic 1 (active), step 110 is entered and step 112 is entered.
Then, the updating of the display buffer 24 is stopped so that the display value is held by the display unit 26. Next, in step 114, a negative logic ready signal RD indicating that data can be output to the outside is set to logic 0 (active). Next, at step 116, it is judged whether the negative logic signal REQ which is the data request signal from the external data processing device 34 is logic 0 (active). If the result of the judgment is negative, the process proceeds to step 118, and it is judged whether or not the interrupt signal I is logic 1 (active). If the determination result is positive, the process returns to step 116. On the other hand, if the determination result in step 118 is negative, the process proceeds to step 120, the ready signal RD is set to logic 1 (inactive), and the display buffer 24 is updated in step 122.
Release the hold of the displayed value and return to the normal mode. On the other hand, when the result of the determination at the above-mentioned step 116 is positive and it is determined that the data request signal REQ is active, the routine proceeds to step 130, where the ready signal RD is set to logic 1 (inactive). Next, in step 132, after transferring the data in the display buffer 24 to the output buffer 32, the data signal DATA is transmitted to the outside using the data signal line M and the clock signal line L. After data transmission, step 13
At 4 the reset signal N is input to the JK flip-flop 38 to make the interrupt signal I logic 0 (inactive), and the routine proceeds to step 122. Hereinafter, the operation when the external data processing device 34 such as the host computer and the printer is not connected will be described with reference to FIG. In this case, when the hold switch 28 is pushed and released once, the hold signal H is output as a pulse as shown in FIG. 3 (A). Then, as shown in FIG. 3 (B), the interrupt signal I becomes active, and the control circuit
The display value is held by 30. At this time, the third
As shown in FIG. 6C, the signal line J having the ready signal RD is also activated, but this signal line J is not connected to the outside and the data request signal REQ is pulled up by the pull-up resistor 39. Therefore, as shown in FIG. 3D, the data request signal REQ becomes invalid and does not change. When the hold switch 28 is pressed and released again in this state, the interrupt signal I becomes inactive, the ready signal RD becomes inactive, the held display value is released, and the routine returns to the normal routine. On the other hand, when the external data processing device 34 is connected, the hold switch 28 also functions as a data output switch, and functions as shown in FIG. That is, when the hold switch 28 is pressed and released, as shown in FIG.
The hold signal H is output as a pulse and is shown in FIG. 4 (B).
As shown in, the interrupt signal I becomes active. Then, as shown in FIG. 4 (C), the ready signal RD also becomes active. In this state, as shown in FIG. 4 (D), when the data request signal REQ from the external data processing device 34 becomes active, the ready signal RD is inverted inactive and the signal line L for transferring the clock signal CK is generated. Data signal DA
Data is transferred as shown in FIGS. 4 (E) and 4 (F) using the signal line M for transferring TA. When the data transfer is completed, a negative logic pulse (reset signal) is output to the signal line N as shown in FIG.
Is reset, the interrupt signal I becomes inactive, the hold of the display value is released, and the routine returns to the normal routine. In the present embodiment, the hold switch 28 maintains the function of holding the display value even when the external data processing device 34 is connected unless the data request signal REQ becomes active. Abnormal data request signal
If REQ does not become active, the display value is held indefinitely, and the display also becomes an alarm. Further, in the present embodiment, since the hold switch 28 is of the toggle operation system, it is not necessary to always press the switch when using it as a data output switch for outputting data to the external data processing device 34, and the operation can be performed. It's simple. The operation method of the hold switch 28 is not limited to this, and it is also possible to use a method of holding the switch while the switch is pressed and releasing the hold when the switch is released. The positive logic signal and the negative logic signal in the above embodiment are not essential and may have the opposite logic type. or,
Various methods are conceivable for data transfer, such as parallel output, as well as serial output of clock signal CK and data signal DATA.

【The invention's effect】

As described above, according to the present invention, the number of switches can be reduced by providing the hold switch with the function of the data output switch in association with the presence or absence of the connection of the external data processing device. At this time, since it is not a method of mechanically switching by connecting the connector, it is inexpensive. Further, when it is used as a data output switch, it has an excellent effect that the hold state of the display value also serves as an alarm for an abnormality of the external data processing device.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of an embodiment of a display value holding type measuring instrument according to the present invention, FIG. 2 is a flow chart showing an operation of a control circuit in the embodiment, and FIG. In the embodiment, a diagram showing an example of signal waveforms of respective parts when the external data processing device is not connected, and FIG. 4 similarly shows an example of signal waveforms of respective parts when the external data processing device is connected. FIG. 5 is a front view showing an example of a conventional electronic caliper in which a hold switch and a data output switch are separately provided. 20 …… Transducer, 22 …… Measurement circuit, 26 …… Display, 28 …… Hold switch, 30 …… Control circuit, 34 …… External data processing device, REQ …… Data request signal, DATA …… Data signal, H: Hold signal, I: Interrupt signal, RD: Ready signal.

Claims (1)

[Claims] 1. A transducer for converting displacement of a measuring element into an electric signal, a measuring circuit for processing the electric signal, an indicator for displaying an output of the measuring circuit as a measured value, a hold switch, and the hold switch. Display value holding type measuring device having a command signal generating means for generating a command signal for holding or canceling a display value by the operation of the display value and a control circuit capable of exchanging signals with an external data processing device by a detachable signal transmitting means. In the control circuit, the display value of the display unit is held or released based on the command signal, and when the data request signal from the external data processing device is received when the hold command signal is generated, the measurement circuit measures the value. Provided with a function of outputting a data signal having value information to an external data processing device and generating a reset signal to the command signal generating means at the end of the output. A display value holding type measuring instrument characterized in that