JPH0640029B2 - Temperature measuring instrument - Google Patents

Description

TECHNICAL FIELD The present invention relates to a thermometer and a temperature measuring device for observing and maintaining a device, and in particular, a function for confirming a previous temperature measurement result prior to a temperature measurement operation. The present invention relates to an electronic temperature measuring instrument equipped with.

[Conventional technology]

This kind of electronic measuring instrument has been adopted in many fields in recent years, and in particular, it is rapidly becoming popular for household use in place of the conventional mercury thermometer because of its simple use.

However, since it does not have a function such as a mercury thermometer that can confirm the previous temperature measurement result prior to the temperature measurement operation, it is necessary to make a note of the previous temperature measurement value for each temperature measurement. It was complicated.

In order to solve such a problem, an electronic temperature measuring device has been proposed which has a memory function and holds the temperature measurement result even after the power is turned off so that the temperature measurement result can be read and displayed as needed. : Electronics Digest, Inc., Dec. 10, 1975, "CMOS IC Handbook," pages 287 to 293).

[Problems to be solved by the invention]

In the above-mentioned conventional technique, a dedicated memory switch for reading the temperature measurement result from the memory unit is provided in addition to the switch for starting temperature measurement, which complicates the circuit configuration and reduces the entire device. Since the size of the switch is increased and the two switches have to be operated separately, the operation is complicated and erroneous, and is not suitable for home use mainly by women and girls.

[Means for solving problems]

The present invention has been made in view of the above circumstances,
A switch that is activated by shaking the main body is provided inside the main body, and the switch is activated along with the operation of the switch, and the previous temperature measurement value stored in the storage unit is displayed before the temperature measurement operation starts, and the measurement is performed. After starting the temperature operation, the temperature measurement value obtained by the temperature measurement unit is written and displayed in the storage unit, which simplifies the circuit configuration and downsizes the entire device and simplifies the operation. It is easy to handle.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a temperature measuring device according to the present invention, in which 1 is a main body case, 2 is a sensor part, 3 is a switch, 4 is a display window, and 5 is a circuit board.

This embodiment will be described by taking a thermometer as an example, but the present invention is not limited to this.

In the figure, a sensor section 2 having a thermosensitive element such as a thermistor built therein is provided at the tip of the body case 1, and a display window 4 for displaying the measured temperature is further provided on the body case 1. Is provided. Further, in the main body case 1, as shown by partially opening the main body case 1, a circuit board 5 provided with various circuits described later is mounted,
The switch 3 is mounted on the circuit board 5.

The switch 3 is configured to operate when the body case 1 is shaken by grasping the portion A of the body case 1. The principle will be described with reference to FIG.

That is, the moving body 6 having a relatively large weight is supported by the returning means 7 such as a tension spring so as to be movable in the directions of the arrows a and b. The returning means 7 moves the moving body 6 in the direction of the arrow b.
Biased in the direction. In the movement path of the moving body 6, switch contact pieces 8 ₁ and 8 _{2 which} are normally separated from each other are provided, and at least the switch contact pieces 8 ₁ have elasticity.

Therefore, when the main body case 1 (FIG. 1) is shaken as described above and a centrifugal force is applied to the moving body 6 in the direction of arrow a, the moving body 6 moves in the direction of arrow a against the urging force of the returning means 7. Then, finally, the moving body 6 hits the switch contact piece 8 ₁ to bend it and bring the switch contact piece 8 ₁ into contact with the switch contact piece 8 ₂ .
This state is the operating state of the switch 3. After that, the moving body 6 is pulled back in the direction of the arrow b by the urging force of the returning means 7, and the switch contact pieces 8 ₁ and 8 ₂ are separated from each other.
Is inactive.

By the way, the switch 3 needs to be in an operating state for a predetermined time or more, as described later. For this reason, it is necessary to hold the moving body 6 as it is for a predetermined time or more after the moving body 6 contacts the switch contact pieces 8 ₁ and 8 ₂ .

FIG. 3 (a) is a cross-sectional view showing one specific example of such a switch 3, 9 is a cylinder, 10 is a holding means, and parts corresponding to those in FIG.

In FIG. 3 (a), the movable body 6 is movably provided inside the cylinder 9 and supported by the returning means 7, and the switch contact pieces 8 ₁ and 8 ₂ project from the outside of the cylinder 9 to the inside. The moving body 6 is provided with the arrow a as described in FIG.
By moving in the direction, the moving body 6 hits the switch contact piece 8 ₁ to bring the switch contact piece 8 ₁ into contact with the switch contact piece 8 ₂ .

Further, on the inner surface of the cylinder 9, a plurality of holding means 10 such as leaf springs are attached. These holding means 1
As shown in FIG. 3 (b), 0 has a cylindrical piece shape, one end of which is slightly bent to form a protrusion 10 '. On the other hand, the cylinder 9 is provided with a through hole 9'so that the protrusion 10 'thereof fits. The protrusion 10' is fitted into this through hole 9'and fixed with an adhesive or the like, so that the holding means 10 is fixed to the cylinder 9 '. Attach to.

Returning to FIG. 3 (a), the holding means 10 having one end fixed to the cylinder 9 is inclined with respect to the inner surface of the cylinder 9 so that the other ends approach each other. The moving body 6
By the movement in the direction of the arrow a, firstly, the holding means 10 is brought into contact with the holding means 10, and then the force is applied to the switch contact piece 8 ₁ to bring it into contact with the switch contact piece 8 ₂ and stop. At this time, the moving body 6 is held by the holding means 10.

The stopped moving body 6 tries to move in the direction opposite to the arrow a after the stop due to the action of the repulsive force of the switch contact piece 8 ₁ (and the switch contact piece 8 ₂ ) and the urging force of the returning means 7, but it is held. Immediate movement by means 10 is not possible.
By appropriately setting the elastic coefficients of the switch contact piece 8 ₁ (and the switch contact piece 8 ₂ ), the returning means 7, and the holding means 10, the holding force of the holding means 10 is overcome, and finally the moving body 6 is held by the holding means 10. It can be released from the holding state and returned to its original position. As a result, the switch contact pieces 8 ₁ , 8 ₂ can be kept in contact with each other for a predetermined time.

FIG. 4 shows another specific example of the switch 3,
In particular, without providing a separate retaining means 10 such as shown in FIG. 3, in which also serves to hold means switch contact piece _81.

That is, mounting one of the switch contact piece ₈₂ on the inner surface of the cylinder 9, and the switch so as to face the contact piece _82, attach the switch contact piece ₈₁ of flexible. The moving body 6
When it moves in the direction of arrow a, it hits the switch contact piece 8 ₁ ,
The switch contact piece 8 ₁ bends and contacts the switch contact piece 8 ₂ .
Due to the bending of the switch contact piece 8 ₁ , the moving body 6 is held between the switch contact piece 8 ₁ and the inner surface of the cylinder 9. Then, after a predetermined time, the moving body 6 is pulled back by the returning means 7, and the switch contact piece 8 ₁ and the switch contact piece 8 ₂ are separated from each other.

Not limited to these, for example, in FIG. 3, the movable body 6 is a magnet, and the switches 8 ₁ and 8 ₂ are contact pieces of the lead switches, so that the switches 8 ₁ and 8 ₂ are
Arbitrary modifications are possible, such as contacting each other while the moving bodies 6 are close to them.

FIG. 5 shows the arrangement of the respective parts in the main body case 1 (FIG. 1), in which the switch 3 and the indicator 11 for displaying the temperature are mounted on the circuit board 5. The switch contacts 8 ₁ , 8 ₂ and the terminals of the display 11 are
It is connected to a predetermined terminal (not shown) of the circuit wiring provided on the circuit board 5. Further, the circuit board 5 is arranged in the main body case 1 so that the display 11 faces the display window 4 shown in FIG. 1 so that the temperature displayed on the display 11 can be observed from the display window 4. I'm running.

As shown in FIG. 5 (b), the sensor unit 2 is provided with a thermosensitive element 12 such as a thermistor, and the terminals of the thermosensitive element 12 are connected to predetermined terminals of the circuit wiring of the circuit board 5 via lead wires 13. It is connected to the. The same applies to FIG. 5 (a).

5 (a) shows the switch 3 and the indicator 11 arranged in the width direction of the body case 1, and FIG. 5 (b) shows those arranged in the length direction of the body case 1. Is.

The circuit formed on the circuit board 5 is a display circuit for displaying the temperature detected by the sensor unit 2 on the display unit 11. A specific example of such a display circuit will be described below.

FIG. 6 is a block diagram showing a specific example of such a display circuit, in which 14 is an oscillator, 15 and 16 are counters, 17 is an RS type latch circuit, 18 and 19 are counters, 20 is a control unit, and 21 is a control unit. Temperature measuring unit, 22 is a storage unit, 23 is a measuring range outside detection unit, 24 is a display decoder, 25 is an RS type latch circuit, 26 is a falling edge detection unit, 27 to 29 are NAND gates, and 30 to 33 are inverters. Therefore, the same reference numerals are attached to the portions corresponding to the above drawings.

In the figure, the oscillator 14, the counters 15, 16, 18,
19, latch circuits 17, 25, control unit 20, temperature measuring unit 2
1. The display decoder 24 and the falling edge detection section 26 are in the reset state when the signal supplied to the reset terminal R is at a high level (hereinafter referred to as "H").

When the switch contact pieces 8 ₁ , 8 ₂ (FIG. 2) of the switch 3 are not in contact (this state is hereinafter referred to as the non-operating state because the switch 3 is open, the switch contact pieces 8 ₁ , 8 ₂ Is in an operating state because the switch 3 is closed), and one input of the NAND gate 27 is "H".
Further, the reset input of the counter 16 and the latch circuit 17 is reset to "H" so that they are reset.

The oscillator 14 is a CR oscillator, a crystal oscillator, or the like, and generates a reference clock MCK. This reference clock MCK
Is divided into a predetermined frequency by the counter 15, and the counter 1
6, 19 and the display decoder 24. The oscillator 14 and the counter 15 are switched between the operating state and the non-operating state by the MCK · N signal obtained by inverting the output signal of the NAND gate 27 by the inverter 30.

The counter 16 and the latch circuit 17 constitute a judging section for judging that the switch 3 has operated. In this determination unit, the counter 16 prevents malfunction due to chattering of the switch 3, and as described above, by shaking the main body case 1 (FIG. 1),
When the switch 3 operates and is closed for a predetermined period (about 0.1 seconds) or more, it overflows and its Q output is inverted from a low level (hereinafter referred to as “L”) to “H”. Also,
The latch circuit 17 is set at the rising edge of the Q output of the counter 16, and the output thereof is inverted from "H" to "L". The counter 16 and the latch circuit 17 are in the reset state when the switch 3 is in the open state, and the reset is released when the switch 3 is in the closed state. The output is inverted from "H" to "L", and the output is inverted from "L" to "H" every time the switch 3 is opened.

The counter 18 is a 1-bit binary counter, which counts one at the falling edge of the output of the latch circuit 17, and its Q output is inverted each time it counts. The Q output of the counter 18 is inverted by the inverter 31 and supplied to the reset terminal R of the display decoder 24 as the GRST1 signal and also to the NAND gate 27. GRS
When the T1 signal is "H", the display decoder 24 is in the reset state and the display 11 is displaying blank (that is, nothing is displayed). Also, GRST1
When the signal becomes "L", the display decoder 24 releases the reset, and the display 11 displays the predetermined data.

The Q output of the counter 18 is supplied to the NAND gate 28 together with the output of the latch circuit 17, and the GRST2 signal is formed. The GRST2 signal is supplied to the reset terminal R of the counter 19, the control unit 20, the temperature measuring unit 21, the latch circuit 25 and the falling edge detection unit 26, and also inverted by the inverter 32 and supplied to the NAND gate 29.

The counter 19 further divides the clock from the counter 15. The Ql output having a predetermined frequency division ratio is supplied to the control unit 20 and controls the temperature measurement timing in the temperature measurement unit 21. Ql
The Qm output having a frequency division ratio of twice the output is supplied to the latch circuit 25 as a set input. After releasing the reset, the latch circuit 25 is set at the first rising edge of the Qm output of the counter 19, and its output is inverted from "H" to "L". This output is supplied to the falling edge detection unit 26 which has already been reset, and the MAX.R signal representing the falling edge is formed. This MAX / R signal is D
The storage unit 22 composed of the mold flip-flop is reset, and the previously measured temperature value held so far is erased. Also,
The output of the latch circuit 25 is also supplied to the NAND gate 29.

When the reset is released, the temperature measuring unit 21 measures the temperature once for each cycle of the Ql output of the counter 9, and this Ql is measured.
The temperature measurement is completed immediately before the rising edge of the output. Then, in synchronization with the rising edge of the Ql output, the temperature measurement value obtained at that time is compared with the temperature measurement value held in the storage unit 22, and the temperature measurement value obtained at that time (hereinafter referred to as the current measurement value). When the temperature value is large, the temperature measurement unit 21 generates a MAX.phi. Signal and writes the current temperature measurement value in the storage unit 22 in place of the temperature measurement value held so far. Therefore, the storage unit 22
In this case, after the temperature measuring unit 11 is reset, the maximum one of the temperature measured values obtained so far is held.

The temperature measurement value stored in the storage unit 22 is read out and supplied to the out-of-measurement range detection unit 23. Out-of-measurement range detector 23
When the temperature measurement value read from the storage unit 12 is out of the predetermined measurement range, is displayed on the display unit 15 to that effect.
Data representing a fixed numerical value, symbol, pattern, etc. is supplied to the display decoder 14 instead of the temperature measurement value.

Here, the predetermined measurement range is 32.0 ° C to 42.0 ° C. When the temperature measurement value by the previous temperature measurement held in the storage unit 12 before being reset by the MAX.R signal, that is, the previous temperature measurement value is displayed, this is 32.0 ° C.
When the value is less than "3", the out-of-measurement range detection unit 23 causes
"2.0 ° C" is displayed and when it exceeds 42.0 ° C,
“42.0 ° C.” is displayed. Further, when the temperature measurement value read from the storage unit 22 after being reset by the MAX.R signal is less than 32.0 ° C., “L0 ° C.”, and when it exceeds 42.0 ° C., “HI ° C.” is displayed on the display unit 15, respectively. In this way, in order to make the displayed contents different between the previous temperature measurement value and the current temperature measurement value outside the predetermined measurement range, the measurement range outside detection unit 23 is controlled by the EN signal which is the output of the latch circuit 17. That is, the EN signal is "L" in the display period of the previous temperature measurement value and "H" in the display period of the current temperature measurement value.

The display decoder 24 forms a display unit together with the display unit 11. The display decoder 24 decodes the output of the out-of-measuring range detection unit 23 after the reset is released because the GRST1 signal becomes “L”, and the display unit The above-mentioned display is performed at 11, and the signal is further preset by the "H" DisPR signal supplied from the inverter 33 to the preset terminal PR, and the display 11 is supplied with a signal for lighting all the segments. .

Next, the operation of this embodiment will be described with reference to FIG. 7 showing the operation timing of each part.

The previous temperature measurement value N ′ _x is held in the storage unit 22 even in the non-use state. Even in this state, the power supply voltage V _DD is applied, the display 11 is in the operating state, and the reset of the counter 18 is released, but its Q output is "L" and G
The RST1 signal is "H". Therefore, when the display decoder 24 is in the reset state, the display 11 is displaying a blank. The input of the NAND gate 27 on the switch 3 side is "H", and the GRST1 signal which is the other input is also "H". Therefore, the output of the NAND gate 27 is inverted by the inverter 30 to obtain the MCKN signal. Is
It is "H", and the oscillator 14 and the counter 15 are in the reset state.

Further, since the output of the latch circuit 17 is "H" and the Q output of the counter 18 is "L", the GRST2 signal is "H", and the counter 19, the control unit 20, the temperature measuring unit 2
1. The latch circuit 25 and the falling edge detection section 26 are also in the reset state. The "H" GRST2 signal is inverted by the inverter 32 and supplied to the NAND gate 29, and the "H" output of the latch circuit 25 is also supplied to the NAND gate 2.
Since it is supplied to 9, the DisPR signal obtained by inverting the output of the NAND gate 29 by the inverter 33 is "L".

In this state, when the switch 3 is closed, the reset between the counter 16 and the latch circuit 17 is released, and
Since the input on the switch 3 side of the NAND gate 27 is inverted from "H" to "L", the MCK.N signal becomes "L" and the oscillator 14 and the counter 15 are also reset. Therefore, the oscillator 14 generates the reference clock MCK, which is divided by the counter 15.

The counter 16 counts the clock output by the counter 15, but when the switch 3 is closed for about 0.1 seconds or more, the counter 16 overflows and its Q output is inverted from "L" to "H". The latch circuit 17 is set by this inversion, and its output is changed from "H" to "L".
Flip to. Counter 18 at the falling edge of this output
Counts by 1, and its Q output is inverted from "L" to "H", and thus the GRST1 signal is inverted from "H" to "L". As a result, the display decoder 24 is released from reset.

Therefore, the previous temperature measurement value N ′ _x read from the storage unit 22 is supplied to the display decoder 24 via the out-of-measurement range detection unit 23. The last temperature measurement value N _'x is decoded,
A numerical value “T ′ _x ° C.” corresponding to this is displayed on the display unit 11. In this case, when the previously measured temperature value N ′ _x is outside the predetermined measurement range, as described above, “32.0 ° C.”
Alternatively, a fixed value of “42.0 ° C.” is displayed.

At this time, since the output of the latch circuit 17 is "L" and the Q output of the counter 18 is "H", the GRST2 signal obtained from the NAND gate 28 is held at "H".

After that, when the switch 3 is opened, the counter 16 and the latch circuit 17 are reset again and the latch circuit 17 is reset.
Is inverted from "L" to "H". Since the counter 18 does not count this, the GRST1 signal remains "L", and the MCK.N signal is "L" even if the input of the NAND gate 27 on the switch 3 side is "H". Therefore, the oscillator 14 and the counter 15 continue to operate.

On the other hand, since the output of the latch circuit 17 becomes "H" and the Q output of the counter 18 is "H", the GRST2 signal obtained from the NAND 28 becomes "L" and the counter 19
Reset is released and the clock from the counter 15 is started to be counted, and the control unit 20, the temperature measuring unit 21,
The reset of the latch circuit 25 and the falling edge detection unit 26 is also released.

Further, since the GRST2 signal is inverted from "H" to "L", the input of the NAND gate 29 on the inverter 32 side becomes "H" and the input of the other latch circuit 25 side is also "H". Is from "L" to "H"
And the display decoder 24 is preset. As a result, the display decoder 24 is prohibited from accepting data from the temperature range outlier 23, and all the segments of the display 11 are turned on.

As described above, by lighting all the segments of the display unit 11, it is possible to confirm that the display decoder 24 and the display unit 11 are normally operated prior to the start of temperature measurement.

When the counter 19 continues counting and counts a predetermined number n, the Ql output is inverted from “L” to “H”, and further,
When n is counted and the count value becomes 2n, the Ql output is inverted from "H" to "L" and the Qm output is inverted from "L" to "H". At the rising edge of this Qm output, the latch circuit 25 is set and its output is inverted from "H" to "L". The falling edge of this output is detected by the falling edge detection unit 26 to form a MAX.R signal, whereby the storage unit 22 is reset. As a result, in the storage unit 22, the previous temperature measurement value N ′ _x is erased and the value 0 is held.

Further, since the output of the latch circuit 25 becomes "L", the output of the NAND gate 29 becomes "H". Therefore, the DisPR signal becomes "L" and the display decoder 2
For 4, the presetting is released. As a result, the temperature measurement value read from the storage unit 22 is supplied to the display decoder 24 through the out-of-measurement range detection unit 23. In this case, this temperature-measurement value is 0 and is outside the measurement range, that is, Since the temperature is lower than 32.0 ° C., the out-of-measurement range detection unit 23 supplies data representing “LO ° C.” to the display decoder 24, and accordingly,
This is displayed on the display unit 11.

When the count value of the counter 9 reaches 3n, the Ql output is inverted from "L" to "H", and the control unit 20 detects this inversion and sends a signal to the temperature measuring unit 21.

On the other hand, in the temperature measurement unit 21, the first temperature measurement is completed immediately before the rising edge of the Ql output of the counter 9, and when a signal is received from the control unit 20, the temperature measurement value is read from the storage unit 22. Compare with the current measured value N ₁ . In this case, since the read temperature measurement value is 0, the current temperature measurement value N ₁ is larger. Therefore, the temperature measurement unit 21 sends the MAX · φ signal to the storage unit 22 and the current temperature measurement value N ₁ is sent. The value N ₁ is written in the storage unit 22. As a result, the display value "T ₁ ° C" for the measured temperature value N ₁ is displayed on the display unit 11.

The period in which the counter 9 counts by n is set to about 0.7 seconds here. Therefore, the Ql output is about 1.4 seconds cycle and the Qm output is about 2.8 seconds cycle. Become.
Therefore, the lighting period of all the segments of the display 11 is about 1.4 seconds, and the above-mentioned "LO ° C" display period is about 0.7 seconds.

In contrast, the temperature measurement value N 'display period of _x, the previous temperature measurement value N is displayed' last must be long enough to ensure sufficient watches _x. By the way, this previous temperature measurement value N '
The display of _x is started when the switch 3 is in the operating state and the rear counter 16 overflows, and then is completed when the switch 3 is in the non-operating state. operating conditions must be maintained longer than the display period of the temperature value N _'x. For this, in the switch 3, the holding plate 10 of the movable body 6 as explained in FIG. 3 provided, or, as described in Figure 4, the holding means of the movable body 6 to switch 8 ₁ It is also used as.

Further, the counter 19 continues counting, and the count value is 4
When it becomes n, the Ql output is inverted from "H" to "L", and when the count value becomes 5n, the Ql output is inverted from "L" to "H". Along with this, in the temperature measuring unit 21, the current temperature measured value N ₂ obtained immediately before that is compared with the temperature measured value N ₁ held in the storage unit 22, and the non-temperature measured value N ₂ of When it is larger, the storage unit 22 rewrites the current temperature value N ₂ . Therefore, the display unit 11 displays the display value "T ₂ ° C" for the measured temperature value N ₂ .

In this way, the counter 19 continues counting as long as the switch 3 does not operate, and the current temperature measurement value and the storage unit 22 are held at the rising edge of the Ql output every 2n counts for about 1.4 seconds. The temperature measurement value is compared, and when the current temperature measurement value is larger, the storage unit 22 rewrites the current temperature measurement value. Therefore, the display unit 11 displays the maximum temperature measured so far, and the displayed value is updated as the temperature rises.

The Qm output of the counter 19 rises every 4n counts, but the latch circuit 25 is kept in the set state as it is, and the above temperature measuring operation is continued.

Next, when the switch 3 is activated, the counter 16 and the latch circuit 17 are reset. Also in this case MCK
Since the N signal is held at "L", the oscillator 14 and the counter 15 are in operation. Therefore, the counter 16 counts the clock from the counter 15, and when it overflows after about 0.1 seconds, the latch circuit 17 is set and its output is inverted from "H" to "L". As a result, the Q output of the counter 18 is inverted from "H" to "L", and G
The RST1 signal is inverted from "L" to "H". Therefore, the display decoder 24 is reset and the display 11 displays a blank.

At the same time, the GRST2 signal is inverted from "L" to "H", and the counter 9, control unit 10, temperature measuring unit 11, latch circuit 25 and falling edge detection unit 26 are reset. In this case, since the MAX.R signal is not generated, the maximum temperature measurement value N _x up to now is held in the storage unit 22 as it is. This temperature measurement value N _x is the previous temperature measurement value for the next temperature measurement.

Furthermore, GRS which is one input of the NAND gate 4
The T1 signal is "H", the other input on the switch 1 side is "L" because the switch 1 is closed, and the MCK.N signal is "L". When is opened, both inputs of NAND gate 4 become "H", therefore MCK · N signal becomes "H".
As a result, the oscillator 14 and the counter 15 are deactivated. Of course, the counter 16 and the latch circuit 17 are also in the reset state.

In this way, the temperature measurement operation is completed and the system is stopped.

As described above, in this specific example, by opening / closing the switch 3, the previous temperature measurement value and the current temperature measurement value are switched and displayed, and the opening / closing of the switch 3 is performed by the main body case 1 (FIG. 1).
Since it is done by simply shaking, the operation becomes very easy. In particular, in the case of a thermometer, like the conventional mercury thermometer, the user can feel resistance by shaking or shaking the body case 1 to start or stop the temperature measurement and display the temperature measurement value. No, it can be handled easily.

When the temperature measurement value is outside the measurement range, different values, symbols, and patterns are displayed for the previous temperature measurement value and the current temperature measurement value. It can be clearly distinguished from the temperature value.

Further, before the temperature measurement is started, the storage unit 12 is reset and the stored content becomes 0. As a result, the display unit 11 displays “LO ° C.”.
Is displayed, which confirms that the temperature measurement has started.

Furthermore, it is possible to confirm that the display decoder 24 and the display unit 15 operate normally by turning on all the segments of the display unit 15 before starting the temperature measurement.

FIG. 8 is a block diagram showing another specific example of the display circuit, in which 18 'is a counter, 34 and 35 are inverters, and the parts corresponding to those in FIG.

In the specific examples shown in FIGS. 6 and 7, the switch 3 is in the operating state, the previous temperature measurement value is displayed on the display 11, and then the switch 3 is in the non-operating state. The display 11 is used to switch to the display of the present temperature measurement value. However, in this specific example shown in FIG. 8, first, the switch 3 is moved by shaking the main body case 1 (FIG. 1). When the operating state is reached, the previous temperature measurement value is displayed on the display unit 11. Next, when the main body case 1 is shaken to activate the switch 3, the display unit 11 switches to the display of the current temperature measurement value. It was done like this.

In order to perform such a display operation, as shown in FIG. 8, the counter 18, the NAND gate 28, and the gate 18 shown in FIG.
Instead of the inverter 31, a counter 18 'consisting of a 2-bit binary counter and inverters 34, 35 are provided. This counter 18 'counts one by one at the falling edge of the output of the latch circuit 17, and every time it counts by one, the output terminals (0), (1), (2) are output in order from "L" to "H". ”
Flip to. The output from the output terminals (0), (1), (2) is
One of them is always "H", and only one of them is "H". And the output of the output terminal (1) is
It is "H" when the counter 18 'is in the reset state and unless the output of the latch circuit 17 falls even if the reset is released, and after the output of the output terminal (2) becomes "H". Further, when the output of the latch circuit 17 falls, the output of the output terminal (0) becomes "H", and thereafter, every time the main body case 1 is shaken, this is repeated.

The other circuits operate in the same manner as described with reference to FIG. 6, but the GRST1 signal for controlling these circuits is the counter 18 '.
The EN signal and the GRST1 signal are obtained by inverting the outputs of the output terminals (1) and (2) of the counter 18 'by the inverters 34 and 35, respectively.

Next, the operation of this specific example will be described with reference to FIG. 9 showing the operation timing of each part, but the description overlapping with the specific examples of FIGS. 6 and 7 will be omitted.

At the time of stop, even if the counter 18 'is reset, only the output of its output terminal (0) is "H". Therefore, the storage unit 2 of the portion assembled to the circuit board 5 is accordingly.
2. Except for the out-of-measurement range detector 23, all are in the reset state. When the power is on, the counter 1
8'is reset and the display 11 is in operation.

Therefore, when the switch 3 is closed, the oscillator 14 and the counter 15 are reset, and when the counter 16 overflows, the counter 18 'counts by 1 and GR
The ST1 signal is inverted from "H" to "L", and the output of the output terminal (1) of the counter 18 'is inverted from "L" to "H". Therefore, the EN signal is changed from "H" to "L". Flip to.
As a result, the display decoder 24 is' value corresponding to _x 'T' preceding temperature measurement value N read from the storage unit 22 is released reset _x ° C. "is displayed on the display unit 11.

After that, even if the switch 3 is opened, the counter 18 'does not count, so this state is held, and "T' _x ° C" is continuously displayed on the display unit 11.

Then, when the switch 3 is closed, the counter 16 starts counting again, and when it overflows, the counter 18 'counts by 1. As a result, counter 1
The output of the output terminal (1) of 8'is inverted from "H" to "L", the EN signal is inverted from "L" to "H", and the output of the output terminal (2) of the counter 18 'is The GRST2 signal is inverted from "L" to "H" and inverted from "H" to "L".

Therefore, similarly to the embodiment shown in FIG. 6, the counter 1
9, the control unit 20, the temperature measuring unit 21, the latch circuit 25 and the falling edge detection unit 26 are reset, and the counter 1
On the basis of the count number of 9, all the segments of the display unit 11 are turned on, the storage unit 22 is reset, and the maximum temperature measurement value by the temperature measurement unit 21 of the display unit 11 is displayed.

After that, even if the switch 3 is opened, the counter 18 'does not count, so that the display of the maximum temperature measurement value by the temperature measuring unit 21 is continued, but when the switch 3 is closed again, the counter 18' is similar to the above. Counts one and GRST
The 1 signal and the GRST2 signal are inverted from "L" to "H". Therefore, the counter 19, the control unit 20, the temperature measuring unit 2
1, the display decoder 24, the latch circuit 25, and the falling edge detector 26 are reset to stop temperature measurement and display, and the switch 3 is opened to reset the oscillator 14, the counters 15 and 16, and the latch circuit 17 to reset. Then, the operation is completed.

As described above, this specific example also has the same effect as the specific example of FIG. 6 shown above, but the display switching between the previous temperature measurement value and the current measurement value is further performed. (Fig.) Is performed by activating the switch 3 and the display period of the previous temperature measurement value can be set to an arbitrary length, for example, for comparison with the current temperature measurement value. In addition, the time required to memorize the temperature measurement value last time can be taken sufficiently.

In this embodiment, the operation period of the switch 3 may be set to a period length (about 0.1 seconds) or more from the start of counting by the counter 16 to the overflow.
Further, in this specific example, by shaking the main body case 1 (FIG. 1) twice in succession, the temperature measurement is immediately started and the current temperature measurement value is displayed with almost no passage of the previous temperature measurement value display period. You can also In this case, the display 1
Since all the segments of 1 and the display of “LO ° C.” are displayed, it is not impossible to distinguish whether the displayed temperature measurement value is the previous temperature measurement value, even if it is mistakenly shaken twice.

In the specific example shown in FIG. 8, each time the main body case 1 is shaken,
The previous temperature measurement value and the current temperature measurement value were switched, but when the main unit case 1 was shaken once, the previous temperature measurement value was displayed and 2
It is also possible to display one of the temperature measurement values depending on the number of times the main body case 1 is continuously shaken, so that the current temperature measurement value is displayed when it is shaken continuously.

As a display circuit for such a display, in FIG. 8, when the main body case 1 is shaken only once (hereinafter, referred to as 1
The GRST1 signal and the EN signal are “L” when the swing is performed, and the GRST1 signal and the GRST2 signal are set to “L” when the swing is performed twice consecutively (hereinafter, referred to as “twice”). It is only necessary to generate the respective signals. Therefore, only the means for generating these signals is different from the specific example shown in FIG. 8, and an example for realizing it is shown in FIG. In the figure, 36 is a counter consisting of a 1-bit binary counter, 37 is a mono-multivibrator, 38 and 39 are falling edge detectors, 4
0 is an edge detector, 41 is an RS type latch circuit, 42,
43 and 44 are AND gates, 46 is an inverter,
The same reference numerals are given to the parts corresponding to FIG.

In FIG. 10, the counter 36 counts by 1 every falling edge of the output of the latch circuit 17, and its Q output is inverted at each count. The mono-multi vibrator (hereinafter referred to as MM) 37, the falling edge detection unit 38 and the AND gate 42 are the number of times the main body case 1 is continuously shaken (thus, the number of times the switch 3 (FIG. 8) is continuously operated). ) Is detected, the pulse ST is not obtained from the AND gate 42 when the main body case 1 is swung once, but the pulse ST is output from the AND gate 42 when swung twice. Is obtained, whereby the latch circuit 41 is set.

That is, the MM 37 is triggered at every rising edge of the output of the latch circuit 17, and the trigger causes the output signal to be "H" to be supplied to the AND gate 42. On the other hand, the falling edge detecting section 38 outputs a pulse DE1 representing each falling edge of the output of the latch circuit 17, but MM37
The pulse ST passes through the AND gate 42 during the period in which the output signal of "H" is "H". Here, in the period in which the output signal of the MM 37 is “H”, when the body case 1 is shaken twice, the body case 1 is swung twice from the rising edge of the output of the latch circuit 17 by the first swing. It is needless to say that the time is set to be slightly longer than the time until the trailing edge of the output due to the next swing of, and is set in consideration of the speed of swinging the main body case 1 by the user. Therefore, the pulse DE1 representing the falling edge of the output of the latch circuit 17 cannot pass through the AND gate 42 with the first swing of the body case 1, and the pulse DE1 generated by the second swing can be AND. Pass through gate 42.
As a result, it is determined whether the main body case 1 has been shaken once or twice, and the latch circuit 41 is set only when it is shaken twice.

When the counter 36 is swung twice, its Q output is inverted twice in a row and returns to the initial level. Counter 36
The latch circuit 41 and the latch circuit 41 can be reset when the power is turned on or by an appropriate reset means. At this time, the Q output of the counter 36 is "L" and the output of the latch circuit 41 is "H". Is the initial level.

The rising and falling edges of the output of the latch circuit 41 are detected by the edge detecting section 40, and the pulse EG representing these edges is used for resetting the counter 36. this is,
When the latch circuit 41 is reset, be sure to use the counter 3
6 is also for resetting and stopping the display circuit.

Further, the falling edge of the output signal of the MM 37 is detected by the falling edge detection section 39, and the pulse DE2 representing this falling edge is supplied to the AND gate 43. Therefore,
This pulse DE2 resets the latch circuit 41 as a pulse RE only when the Q output of the counter 36 is "H". As a result, after the latch circuit 41 is set,
When the body case 1 is shaken once, the latch circuit 41 is always reset. When the body case 1 is shaken twice, the Q output of the counter 36 is inverted twice and becomes "L" before the falling edge detection section 39 generates the pulse DE2. 41 is not reset. After the latch circuit 41 is reset, the main body case 1
Is shaken once and the latch circuit 41 is reset,
The edge detector 40 generates a pulse EG, and the counter 36
Is also reset.

The EN signal is the Q output of the counter 36 inverted by the inverter 46, and the GRST2 signal is the output of the latch circuit 41. Also, the GRST1 signal is the EN signal and the GR
This is a signal obtained by processing the ST2 signal by the AND gate 44.

First, the body case 1 is shaken once, and the switch 3 (8th
The operation of this specific example in the case where (FIG.) Operates only once will be described with reference to the timing chart of FIG.

When the switch 3 is actuated by shaking the body case 1, the output of the latch circuit 17 is inverted from "H" to "L", and the counter 36 counts by 1, as described above.
As a result, its Q output is inverted from "L" to "H" and E
The N signal is inverted from "H" to "L", and the GRST1 signal is also inverted from "H" to "L" to display the previous temperature measurement value.

On the other hand, the falling edge detection section 38 generates a DE1 pulse at the falling edge of the output of the latch circuit 17, but the latch circuit 17 resets the output to "H" as described above. Since the output signal of the latch circuit 41 does not become "H", the latch circuit 41 is not set, and the output thereof, therefore, the GRST2 signal is held at "H".

After that, when the body case 1 is shaken once again, the counter 36 counts by 1 at the rising edge of the Q output of the latch circuit 17, the Q output is inverted from "H" to "L", and the EN signal becomes Invert from "L" to "H". Also in this case, the MM 37, the falling edge detector 38 and the AND gate 42 operate as described above, and the latch circuit 41 is not set. Therefore, the GRST1 signal is also inverted from "L" to "H". This causes the display circuit to stop.

Next, the operation when the main body case 1 is swung twice will be described with reference to the timing chart of FIG.

In this case, the Q output of the counter 36 becomes "H" at the falling edge of the output of the latch circuit 17 associated with the first operation of the switch 3, but the latch circuit 17 associated with the second operation of the switch 3 operates. It immediately goes to "L" at the falling edge of the output. Therefore, the EN signal becomes "L" only during the period when this output is "H". At this time, the EN signal becomes "L" and the GRST1 signal also becomes "L", and the display decoder 24 (FIG. 8) is reset.
Therefore, for a short period, the previous temperature measurement value is displayed.

On the other hand, as described above, the latch circuit 41 is set at the second falling edge of the output of the latch circuit 17,
The output, that is, the GRST2 signal is inverted from "H" to "L". At the same time, as described above, the Q output of the counter 36 is inverted from “H” to “L” and the EN signal is inverted from “L” to “H”, so that the GRST1 signal is kept at “L” as it is. Then, as described above, all the segments of the display 11 (FIG. 8) are lit, “LO ° C.” is displayed, and the maximum value of the current measured value is displayed.

In this case, a pulse EG is generated from the edge detector 40 at the trailing edge of the output of the latch circuit 41, but the Q output of the counter 36 is "H" to "L" due to the trailing edge of the output of the latch circuit 17. Since it is reversed to, there is no particular problem. In addition, the falling edge detection unit 39 also uses MM3.
A pulse DE2 is generated at each falling edge of the output signal of No. 7, but at this time, the Q output of the counter 36 is "L".
Therefore, the latch circuit 41 is not reset.

After that, when the main body case 1 is shaken once, the output of the latch circuit 17 causes a falling edge to cause the counter 36.
Counts by 1, and its Q output becomes "H".

In addition, at the rising edge of the output of the latch circuit 17, MM3
7 is triggered, and an output signal of "H" is generated for a certain period, but a pulse DE2 is generated from the falling edge detection section 39 at the falling edge of this output signal. At this time, since the Q output of the counter 36 is "H", the pulse RE is output from the AND gate 43 and the latch circuit 41 is reset. As a result, the GRST2 signal is inverted from "L" to "H", and the temperature measuring operation is stopped.

When the latch circuit 41 is reset, a pulse EG is generated from the edge detector 40 at the rising edge of its output, the counter 36 is reset, and its Q output is inverted from "H" to "L". Therefore, the EN signal is inverted from "L" to "H", the GRST1 signal is also inverted from "L" to "H", and the operation of the display circuit is stopped.

Next, the operation when the main body case 1 is first shaken once and then twice is described with reference to the timing chart of FIG.

In the first swing, as described in FIG. 11, the Q output of the counter 36 is “H”, the EN signal and G
The RST1 signal is "L", and G from the latch circuit 41
The RST2 signal is "H". At this time, the previous temperature measurement value is displayed.

Next, when the body case 1 is swung twice, the counter 36 is output at the first falling edge of the output of the latch circuit 17.
The Q output of the counter 36 is inverted from "H" to "L", the EN signal is inverted from "L" to "H", and the Q output of the counter 36 is "L" at the next falling edge of the output of the latch circuit 17. To "H" and the EN signal is inverted from "H" to "L".

Further, as described above, the latch circuit 41 is set at the second falling edge of the output of the latch circuit 17,
The GRST2 signal is inverted from "H" to "L". This G
At the falling edge of the RST2 signal, the edge detection unit 40 outputs E
A G pulse is generated and the counter 36 is reset. Therefore, the Q output of the counter 36 changes from "L" to "H" at the second falling edge of the output of the latch circuit 17, but immediately from "H" to "L" by the above EG pulse. Invert.

In this way, if the main body case 1 is shaken once and the temperature measurement value is displayed last time, and then it is shaken twice more, the EN signal becomes “H”, the GRST2 signal becomes “L”, and the display 11 All segments are lit, the "LO ° C" display value, and the maximum value of the current measured value are displayed.

After shaking the main body case 1 twice to display the current temperature measurement value, and further shaking the main body case 1 twice,
The display of the current measured value continues as it is. The timing chart in this case is shown in FIG.
The operation by the second swing is the G from the latch circuit 41.
Except for the fact that the RST2 signal is "L", the operation is the same as the first two-time swing operation, and a description thereof will be omitted.

As described above, in the display circuit using the signal generating means shown in FIG. 10, the displayed temperature measurement value differs depending on whether the body case 1 is shaken once or twice. After the previous temperature measurement value and the current temperature measurement value are displayed,
When shaken, the operation of the display circuit stops.

Although the specific examples of the display circuits have been described above, the power supply voltage V _DD applied to these may be constantly applied by incorporating a battery in the main body case 1, but a power supply voltage V _DD may be provided by using a bush switch or the like. The V _DD may be applied or cut off. The power supply voltage V _DD may be a rectified commercial AC voltage.

In the above description, specific numerical values are shown, but these are merely examples, and the present invention is not limited by these values.

〔The invention's effect〕

As described above, according to the present invention, it is possible to perform switching display between the previous temperature measurement value and the current temperature measurement value and start and stop of the temperature measurement operation even with the operation of a single switch. Since the switch is configured to operate by shaking the body case, it can be operated by the same operation as the conventional mercury thermometer of shaking the body case, and the operation is extremely simple. It is extremely easy to handle, and further, an excellent effect that the structure is simple and the size can be reduced can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a temperature measuring device according to the present invention, FIG. 2 is a diagram showing the operating principle of the switch shown in FIG. 1, and FIGS. 3 and 4 are diagrams showing specific examples of the switch. Figure,
FIG. 5 is a perspective view showing an arrangement example of each component in the main body case of FIG. 1, FIG. 6 is a block diagram showing a specific example of the display circuit used in the embodiment shown in FIG. 1, and FIG. Is a timing chart for explaining the operation of the display circuit shown in FIG.
FIG. 8 is a block diagram showing another specific example of the display circuit used in the embodiment shown in FIG. 1, and FIG. 9 is a timing chart for explaining the operation of the display circuit shown in FIG.
FIG. 0 is a block diagram of an essential part showing an example in which the current measured value is displayed by swinging twice, and FIGS. 11 to 14 are for explaining the operation of the display circuit shown in FIG. 10, respectively. It is a timing chart. 1 ... Main body case, 2 ... Sensor part, 3 ... Switch,
4 ... Display window, 5 ... Circuit board, 6 ... Moving body, 7 ...
Returning means, 8 ₁ , 8 ₂ ... switch contact piece, 9 ... cylinder, 1
0 ... holding means, 11 ... display, 21 ... temperature measuring unit, 2
2 ... storage unit, 24 ... display decoder.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Isao Imagawa 4680 Ikata, Hachijo-machi, Tagawa-gun, Fukuoka Prefecture Kyushu Hitachi Maxell Co., Ltd. (56) Reference JP-A-60-181624 (JP, A) Showa 54-26374 (JP, U) Actually opened Showa 52-25278 (JP, U)

Claims (3)

[Claims] 1. A switch in a case which is operated by shaking the case, and a detection means for detecting an operation time of the switch and generating a detection signal when the operation time reaches a predetermined time. A counter that starts a counting operation after the detection signal is generated, a reset signal generator that generates a reset signal having a predetermined pulse width with a predetermined count value of the counter, and the reset signal according to the count value of the counter. Control unit that generates a detection pulse of a constant cycle after occurrence of the temperature, a temperature measurement unit that detects the temperature for each detection pulse, and a reset state only during the pulse period of the reset signal, which is higher than the stored temperature data. A storage unit for storing the detected temperature data of the temperature measuring unit indicating the temperature, and a temperature indicated by the temperature data stored in the storage unit together with the operation of the switch. And a counter, the reset signal generator, and the controller by the operation of the switch when the display indicates the temperature indicated by the temperature data stored in the storage after reset. , A reset unit for resetting the temperature measuring unit and the display unit, and the switch is always biased in the first direction, and by shaking the case, the biasing force is applied to the switch. A movable body that moves in the second direction against it, holding means that holds the movable body that has moved in the second direction, and an electrical contact piece that is in an operating state by the movable body that is held by the holding means. When the electric contact piece is in an operating state by holding the moving body by the holding means, the holding of the moving body is released by the biasing force and the electric contact piece is in an inoperative state. The time until it becomes above the switch A running time, by shaking the casing, prior to this measurement, the temperature measuring device, characterized in that the capable of displaying temperature of previous measurement. 2. The temperature measuring device according to claim 1, wherein the temperature measuring unit starts the temperature measuring operation when the operation of the switch is released. 3. The temperature measuring unit according to claim 1, wherein the temperature measuring unit starts the temperature measuring operation when the switch is activated again after the activation of the switch. Temperature measuring device.