JPS6319785Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention automatically turns off the power in so-called electronic scales such as electronic weighing scales, counting scales, and printer-equipped scales when the electronic scale is not used for a certain period of time. This relates to a device for

Conventional technology A so-called electronic scale, which electrically detects the amount of deviation of a weighing pan on which an item is placed to determine the weight of the item, and also calculates the number of items, price, etc. using an electronic circuit, has a weight scale and a counter. There are various types such as scales and scales with printers.

Problems to be Solved by the Invention In these electronic scales, power is continuously supplied from the time of start of use to the time of end of use, regardless of whether or not weighing is in progress. For this reason, electronic circuits, numeric displays, etc. consume electricity even when not being weighed, which is uneconomical. In addition, the numeric display has a lighting lifespan, and the lifespan is determined by the energization time, regardless of the number of actual measurements, so it is irrational to display the display during non-measurement periods. Particularly when a battery is used as a power source for an electronic scale, this wasteful power consumption during non-weighing periods is undesirable as it increases the number of battery replacements.

Means to Solve the Problems Therefore, in view of the above-mentioned problems, this invention includes an initial activation power switch circuit that temporarily controls the supply of electricity from the power supply to all circuits of the electronic scale, and a parallel circuit with the initial activation power switch circuit. The balance is connected to a switching circuit that operates from an open state to a closed state to energize all circuits of the electronic scale, and is energized and set through this switch circuit by the operation of the above-mentioned initial activation power switch circuit. a holding means for operating the switching circuit from an open state to a closed state, and then self-maintaining the set state by applying electricity through the switching circuit to maintain the closed state of the switching circuit; Detection means for detecting whether measurement is in progress or non-measurement; and resettable timer means for starting a timer when the detection means detects non-measurement and resetting the timer when it detects measurement. The resettable timer means resets the holding means after the timer time has elapsed, and when the holding means is reset, the switching circuit operates the switch from the closed state to the open state to completely shut down the electronic scale. It is designed to cut off power to the circuit.

Function: With the above configuration, the power supply is automatically turned off when the electronic scale is not in use, thereby saving power consumption and extending the life of the display.

Example This invention will be described below with reference to embodiments.

In Figure 1, 1 is a power supply, 2 is a power supply terminal, 3
4 is a switching circuit composed of a transistor or a relay, etc.; 4 is an initial activation power switch circuit connected in parallel with the switching circuit 3, and temporarily controls the supply of electricity from the power supply 1 to all circuits of the electronic scale; 5;
is the differential circuit, and 6 is the ON- of switching circuit 3.
It is a holding means for the RS flip-flop circuit etc. that controls the OFF state, and the power supply is connected to the switching circuit 3.
The set terminal S is supplied with the output of a differentiating circuit 5 which detects the rise of the voltage on the output side of the switching circuit 3. 7 resets the holding means 6 when the set time of the timer elapses without being detected during weighing;
8 is a timer time setting section that sets the time in the resettable timer means 7; 9 is a counter; 10 is an oscillator that generates a clock pulse; 11 is a Timer time setting section 8
A first comparator 12 digitally compares the output of the counter 9 with the output of the counter 9 and outputs an output when the two match, and a first comparator 12 compares the weighing weight W input from a weight detecting section (not shown) and whether the weighing pan is empty or not. Compare the constant weight Wo (for example, 0g or 10g) to determine whether W>
2nd comparator outputs during measurement when Wo, 13
is an OR gate. In this embodiment, the second comparator 12 serves as the detection means during measurement.

The operation of this device will be explained as follows with reference to the timing diagram shown in FIG.

When the power supply 1 is connected to the power supply terminal 2 before startup, the switching circuit 3 is in an OFF state, the power supply 1 is not connected to each circuit of the electronic scale, the weighing function does not work, and the display is off. When the initial operation power switch circuit 4 is pressed momentarily in this state, the holding means 6 is energized via this switch circuit 4, and at the same time, the holding means 6 which had been in the reset state until then is turned on.
The potential a of the set terminal S becomes high momentarily by the differentiating circuit 5 which detects the rise of the current flowing through the initial activation power switch circuit 4 and emits one pulse, and the holding means 6 is inverted and the Q output The potential b of the terminal becomes a high potential. The switching circuit 3 is turned on by this potential b, and the potential c on its output side becomes the same high potential as the power supply terminal 2 and is supplied to each circuit of the electronic balance. As a result, the holding means 6 self-holds its set state and keeps the switching circuit 3 in the ON state, and the operation of the entire electronic scale is started, the weighing function begins to work, and the display is also turned on. Further, each circuit of the resettable timer means 7, the second comparator 12, and the OR gate 13 also start operating from this point. In addition,
The potential a of the set terminal S of the holding means 6 when the initial operation power switch circuit 4 is pressed at this startup is also supplied to the OR gate 13 at the same time, and the OR gate 13 resets the counter 9 at this high potential. The count value of the counter 9 is reset to zero by applying it to the terminal R. Thereafter, the counter 9 counts the clock pulses d output from the oscillator 10 from the time when the output potential a of the differentiating circuit 5 becomes a low potential. Then, the count value of the counter 9 is determined by the first comparator 11.
It is compared with the output of the timer time setting section 8. young
The OR gate 13 continues to output a low potential and the count value increases, and the timer time setting section 8 as shown by the dotted line in Figure 2
When the output matches the output of the holding means 6, a reset signal e is outputted and inputted to the reset terminal R of the holding means 6, and the holding means 6 is inverted. Then, since the potential b of the Q output terminal becomes a low potential, the switching circuit 3
is turned off, the power supply to each circuit of the electronic scale is stopped, the balance returns to the state before startup, the weighing function stops, and the display goes off.

However, since the timer time setting section 8 is set to a timer time T that is longer than the normal measurement interval, the measurement is normally started before the first comparator 11 outputs the reset signal e. Then, when an item is placed on the weighing pan and the weight detection section gradually increases the weighed weight W, the second comparator 12
is the constant weight Wo for which this weighing weight W is set
OR gate 1 by exceeding (W>Wo)
A high potential reset signal f is sent to the counter 9 via
Output. While the reset signal f is at a high potential, the count value of the counter 9 remains reset to zero, so the first comparator 11 outputs the reset signal e.
is not output. When one measurement is completed and the item is removed from the weighing pan, the weighed weight W becomes zero and is equal to or less than the set constant weight Wo (W≦
Wo), so the reset signal f becomes low potential. Then, the reset state of the counter 9 is released and it starts counting the clock pulse d again, and the count value gradually increases. If weighing is not performed during the time T set in the timer time setting section 8, each circuit operates as indicated by the dotted lines in FIG. 2 as described above, the holding means 6 is reset, and the potential of the Q output terminal is As a result, switching circuit 3
The electronic scale is turned off and each circuit of the electronic scale and the power supply 1 are cut off. However, if the next measurement is started before the timer time T has elapsed, the second comparator 12 detects this and outputs the high potential reset signal f.
It is sent to the counter 9 via the gate 13. Then, the count value of the counter 9 is reset to zero and the counting operation is stopped, so the switching circuit 3 is turned on.
The state continues and power is continuously supplied to each circuit of the electronic scale.

That is, when the circuit of the configuration shown in FIG.
During this period, the switching circuit 3 is configured to remain in the ON state as long as the item is placed on the weighing pan.

Effects of the Invention As explained above, according to the present invention, once the power is turned on in an electronic scale, if the next weighing is not performed within a certain period of time after the completion of the weighing operation, the power is turned off electronically. Since it is cut off from all circuits of the scale, power consumption can be saved, and the actual period of use of internal circuits such as the display can be shortened, resulting in a long-life electronic scale.

It also controls ON/OFF of electricity to all circuits of the electronic scale. Therefore, when the power is off, the power supply does not consume any power at all (no power is passed to each circuit).Thereby, there is no wasted power consumption, which is economical, and is especially effective when the power source is a battery. It is.

Also, during measurement, the resettable timer means is reset, and when the measurement is completed and the non-metering state is reached, this timer means is activated and the electricity is turned off after a certain period of time. Therefore, the power will not be turned off during measurement. This ensures that the weight is displayed during weighing. Also, after weighing, you can check whether the weight display has become zero.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a timing chart explaining its operation. 1...Power supply, 2...Power terminal, 3...Switching circuit, 4...Initial operation power switch circuit, 5
...Differentiating circuit, 6... Holding means, 7... Resettable timer means, 8... Timer time setting section,
9... Counter, 10... Oscillator, 11... First
Comparator, 12... Second comparator, 13... OR gate, A... Detection means during measurement, T... Timer time.

Claims (1)

[Claim for Utility Model Registration] An initial activation power switch circuit that temporarily controls power supply to all circuits of the electronic scale from the power source, and an initial activation power switch circuit that is connected in parallel with the initial activation power switch circuit and changes from an open state to a closed state. A switching circuit is activated to energize all circuits of the electronic scale, and the above-mentioned initial activation power switch circuit is activated, and the above-mentioned switching circuit is opened by being energized and set through this switch circuit. holding means for operating the device into the closed state from the start and then self-maintaining the set state by applying electricity through the switching circuit to maintain the closed state of the switching circuit; and a resettable timer means that starts a timer when it detects that the measuring device is not measuring, and resets the timer when it detects that the measuring device is measuring. The holding means is reset after the timer time has elapsed, and when the holding means is reset, the switching circuit operates a switch from a closed state to an open state, thereby cutting off power to all circuits of the electronic scale. An automatic power-off device for electronic scales.