JPH0210404Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a display alarm circuit suitable for a digital measuring device.

The display alarm setting circuit of radiation measuring equipment, etc.
As shown in the figure, the signal from the detection circuit D that integrates the signals from the detector and outputs the integrated value is input, and based on this, the signal is outputted as a binary coded decimal signal and a digit selection signal. A split drive circuit 2, a BCD7 segment drive circuit 3 that drives display segments with a binary coded decimal signal, a digit drive circuit 5 that selects a display digit with a digit selection signal, and both drive circuits 3, 5.
a display section 1 consisting of an LED display 4 connected to the LED display 4 to digitally display the integrated value; and a setting frequency divider circuit A that divides the signal from the detection circuit D and outputs a signal for each frequency division stage; Alarm setting device B is selectively connected to the binary coded decimal signal terminal of circuit A to set the alarm value, and 1/10 frequency division is used to divide the output signal from alarm setting device B and set the magnification. The alarm circuit F was configured to be driven by a signal from an alarm setting section E consisting of devices C and C. This display alarm setting circuit requires a setting frequency divider circuit for setting the alarm value and a frequency divider circuit for setting the magnification, resulting in a complicated circuit configuration and an increase in cost.

In view of these problems, the present invention selects the binary coded decimal signal and digit selection signal from the time division drive circuit that drives the digital display according to the set values, and uses these signals to select the diodes forming the AND circuit. It is an object of the present invention to provide a display alarm setting circuit which eliminates the need for a sound alarm setting frequency dividing circuit or a frequency dividing means for setting a multiplier setting rate by inputting the signal to an alarm device via the alarm.

Therefore, the details of the present invention will be explained below based on illustrated embodiments.

FIG. 2 is a block diagram of an apparatus showing an embodiment of the present invention, in which reference numeral 1 is a digital display unit, and 2 from the time division drive circuit 2 to which the signal from the radiation detection circuit D is input. The evolved decimal signal is outputted via the BCD 7 segment drive circuit 3, the digit selection signal is outputted to the LED display 4 via the digit drive circuit 5, and the signal from the detection circuit D is configured to be digitally displayed. Reference numeral 6 denotes an alarm setting circuit which is a characteristic part of the present invention, and is connected to the time division drive circuit 2 in the display section.
The cathodes of first diodes 7a, 7b, 7c, and 7d are connected to each of the output terminals of the evolved decimal signal,
The anode is a selection switch S1, S2, S3, S4
The anode of the second diode 9 is connected to the anode of the second diode 9 via an alarm setting device 8 consisting of the following. The second diode 9 has its cathode connected to the digit selection signal output terminal of the time division drive circuit 2 via a magnification setting device 10 consisting of a switch, and its anode connected to the positive polarity power supply V.
The first diodes 7a, 7b, 7c, and 7d form an AND circuit. An alarm circuit 12 is connected to the connection point between the load resistor 11 and the diode 9, which detects the terminal voltage of the load resistor 11 and is activated when the voltage reaches zero potential.

In this embodiment, a predetermined value, for example, an alarm value, is set to "8" by the alarm setting device 8 and the magnification setting device 10.
, set the magnification to "10". In such a state, when the measurement value from the detection circuit D is input,
The measured value is digitally displayed on the display 4.
At this stage, the measured value does not match the set value, so a conductive path is formed from the load resistor 11 to the time division drive circuit 2 through the selected diodes 7d and 9, and the load resistor 11 becomes zero potential, and the alarm circuit 12 is not activated. As the measurement continues in this way, when the measured value matches the alarm value and the magnification, the diodes 7d and 9 are cut off by the binary coded decimal signal and digit selection signal from the time division drive circuit 2, and the load resistance 11 to the time division drive circuit 2 is cut off, the terminal voltage of the load resistor 11 increases, and the alarm circuit 12 detects this and issues an alarm.

As explained above, according to the present invention, the binary coded decimal signal of the time division drive circuit for digital display is connected to a diode through a selection means for switching each digit selection signal, and the potential at the connection point is detected. As a result, the alarm setting circuit can be realized with a simple configuration without requiring a frequency dividing circuit in the alarm setting circuit.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of a conventional display alarm setting circuit, and FIG. 2 is a block diagram of a circuit showing an embodiment of the present invention. 8...Alarm setting device, 10...Magnification setting device.

Claims (1)

[Scope of utility model registration request] a time division drive means for converting the detection signal into a binary coded decimal signal and a digit selection signal; a digital display means for displaying the measured value by the signal from the means; and a time division drive means for each binary coded decimal signal of the time division drive means. an alarm value setting means connected via a diode, a magnification setting means for selecting a digit selection signal of the time division driving means, a diode connecting the output of the alarm value setting means and the output of the magnification setting means, and the diode. A display alarm setting circuit consisting of an alarm means activated by a potential change on the alarm value setting means side.