JPS6148399B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to appropriate temperature notification for an electric iron, and provides an electric iron that notifies the appropriate temperature by making a sounding body sound for a certain period of time when the base surface temperature of the iron reaches the appropriate temperature. It is.

A conventional electric iron has a configuration in which a lamp is connected in parallel with a heater, and when the heater is energized, the lamp is turned on, and when the heater is not energized, the lamp is turned off.

However, although this configuration is simple, it has the following drawbacks.

You can't tell whether the temperature has reached the right temperature by watching the lamp change from turning on to turning off, or from turning off to turning on again.

When the lamp is off, it is difficult to tell whether the iron is malfunctioning and is not receiving power, or whether it is adjusting the temperature normally.

In particular, if you forget to notice that the light goes off during the operation of turning on → off → on, you may end up deciding that the temperature is not at the appropriate temperature even though it is.

The present invention first detects a signal when the power to the heater switches from on to off or from off to on after setting the temperature, and triggers a latch circuit with a differential pulse of this signal to change the state to a latch state. The output of this latch circuit is used as a signal to notify the appropriate temperature, and a latch release circuit is also provided to release the latch state when the set temperature is changed, and then activate the latch circuit when it changes to the latch state. The output of the monostable multivibrator is used to make a sounding body sound to notify that the temperature has reached the appropriate temperature for a certain period of time.

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

1 is an operating device for arbitrarily setting the temperature of the base. 2 is a temperature detection element for detecting the temperature of the base. 3 is a comparator, which compares the temperature set by the operating device 1 and the temperature of the base. Reference numeral 4 denotes a power control element, which is driven by the output of the comparator 3 and keeps the base at a constant temperature. 5 is a differentiating circuit, which differentiates the output signal of the comparator 3. Reference numeral 6 denotes a latch circuit, which is brought into a latch state by the output of the differentiating circuit 5. 7 is a monostable multivibrator which is driven by the output of the latch circuit 6; Reference numeral 8 denotes a sounding element, which continues to sound while the monostable multivibrator 7 is outputting a signal for a certain period of time. Reference numeral 9 denotes a latch release circuit, which releases the latch state of the latch circuit 6 by the output of the operating device 1.

Next, FIG. 2 shows an outline of the structure of the main body.

10 is a heater, 11 is a base, 12 is a vaporization chamber for generating steam, 13 is a needle valve,
14 is a steam hole, 15 is a cover that covers the base 11, and 16 is a handle body that is fixed on the cover 15. 17 is a water tank for generating steam, and 18 is a steam opening/closing button attached to the top of the water tank 17. Reference numeral 19 denotes a switch board arranged in the grip space of the handle body 19, on which the operating device 1 is mounted. 20 is a control board similarly arranged in the body space of the handle body 16. Note that the temperature sensing element 2 is attached to the base 11 in a thermosensitive manner.

Next, a specific example of the electric iron will be described with reference to FIG. 3.

Reference numeral 21 denotes an AC power source, to which a series circuit of the heater 10 and a normally open relay contact 22 is connected. This relay contact 22 closes when current flows through a relay coil 23 (described later), thereby energizing the heater 10. Further, a series circuit of a diode 24, a resistor 25, and a capacitor 26 is connected to the AC power supply 21. This capacitor 26 serves as a constant voltage DC power source for a control circuit to be described later. A ring counter 27 with a preset function is connected in parallel to the capacitor 26, and one end 28 is connected to one end of the capacitor 26, and the other end 29 is connected to the other end of the capacitor 26 and kept at ground potential. A switch 30 is opened and closed by operating the operating device 1, and is connected between one end of the capacitor 26 and the first input terminal 31 of the ring counter 27 with a preset function. 32 is a resistor connected between the second input terminal 33 and third input terminal 34 of the ring counter 27 with preset function, and 35 is connected to the ground potential side of the third input terminal 34 of the ring counter 27 with preset function and the capacitor 26. The time constant of the clock pulse for switching the output of the ring counter 27 with a preset function is determined by the values of the resistor 32 and the capacitor 35. 3
6, 37, 38, and 39 are the first output terminal, second output terminal, third output terminal, and fourth output terminal, respectively, of the ring counter with preset function 27; Resistor 4 via light emitting elements 40, 41, 42, 43, respectively.
The resistor 44 is commonly connected to one end of the resistor 44, and the other end of the resistor 44 is connected to one end of the capacitor 26. The circuit diagram shows four light emitting display elements 40, 4 as an example.
1, 42, and 43 constitute a set temperature display.

One end of the temperature sensing element 2 is connected to one end of the capacitor 26, and the other end is connected to the inverting input terminal 45 of the comparator 3.
and is connected to the second output terminal 37 of the ring counter 27 with preset function via the resistor 46.
It is also connected to the third output terminal 38 of the ring counter 27 with a preset function via a resistor 47, and further to the fourth output terminal 39 of the ring counter 27 with a preset function via a resistor 48. Resistors 49 and 50 are connected in series, and this series circuit is connected in parallel to capacitor 26. and resistance 4
The connection point between the resistor 9 and the resistor 50 is connected to the non-inverting input terminal 51 of the comparator 3.

52 is a transistor connected in series to the relay coil 23, and this series circuit includes a capacitor 26.
are connected in parallel. The output of the comparator 3 is inputted to the base electrode of the transistor 52 via the resistor 53, and when the output of the comparator 3 is at a high level (H), the transistor 52 is driven to flow a current to the relay coil 23 and close the relay contact 22. Close. 54 is relay coil 2
This is a diode connected in parallel to 3.

55 is a capacitor whose one end is connected to the collector of the transistor 52, 56 is a thyristor whose gate terminal is connected to the other end of the capacitor 55, and whose cathode is connected to the ground potential side of the capacitor 26. 57 is a transistor whose emitter is connected to one end of the capacitor 26 and whose collector is a resistor 58.
The anode of the thyristor 56 is connected to the anode of the thyristor 56 via the thyristor 56. A resistor 59 has one end connected to the base of the transistor 57. A resistor 60 has one end connected to the resistor 59 and the other end connected to the ground potential side of the capacitor 26. A resistor 61 has one end connected to the base of the transistor 57 and the other end connected to one end of the capacitor 26. 62
is a resistor whose one end is connected to the gate of the thyristor 56 and the other end is connected to the ground potential side of the capacitor 26. Further, the input terminal 63 of the monostable multivibrator 7 is connected to the anode of the thyristor 56. 64, 65, 66, 67, 68, 69, 7
0 is a component of the monostable multivibrator 7, and since the monostable multivibrator 7 itself is common, detailed explanation will be omitted. 71 is an output terminal of the monostable multivibrator 7. 7
2 is a transistor for driving the sounding element 8, whose base terminal is connected to the output terminal 71 of the monostable multivibrator 7, and whose emitter is connected to the capacitor 2.
The collector is connected to one end of the sounding body 8 . The other end of the sounding body 8 is connected to the ground potential side of the capacitor 26.

Next, the operation of the above circuit will be explained.

First, the operation of the ring counter 27 with preset function will be explained with reference to FIG.
The first output circuit 75 is driven to bring the first output terminal 36 to a low level (L).

At this time, the second output circuit 76, the third output circuit 77, and the fourth output circuit 78 all have an open collector type configuration, and the second output terminal 3
7, the outputs of the third output terminal 38 and the fourth output terminal 39 are all at a high level. Next, switch 3
0 is closed and the first input terminal 31 is set to high level, the oscillation circuit 79 oscillates according to a time constant determined by the values of the resistor 32 and capacitor 35 connected to the second input terminal 33 and the third input terminal 34. , outputs a clock pulse. When this clock pulse is input to the ring counter 73, the second output circuit 76 is driven, and only the second output terminal 37 becomes low level, and the other output terminals 36, 38, and 39 become high level. Furthermore, when the next clock pulse is input to the ring counter 73, the third output circuit 77 is driven, and only the third output terminal 38 becomes low level.
When the next clock pulse is input to the ring counter 73, the fourth output circuit 78 is driven, and only the fourth output terminal 39 becomes low level. Furthermore, when the next clock pulse is input to the ring counter 73, the first output circuit 75 is driven, and only the output of the first output terminal 36 becomes low level.

Repeat the same below. Next, the operation of the circuit configuration shown in FIG. 3 will be explained.

First, when the AC power supply 21 is connected, the first output terminal 36 of the ring counter 27 with preset function is connected.
becomes a low level, and a current flows through the first light emitting display element 40, lighting it up. Since the outputs of the second output terminal 37, the third output terminal 38, and the fourth output terminal 39 are at a high level, the potential at the connection point between the temperature sensing element 2 and the resistor 46 is high, and therefore the inverting input terminal 45 of the comparator 3 The potential of the transistor 52 is higher than the potential of the non-inverting input terminal 51, and the output of the comparator 3 becomes low level.
is not driven and no current flows through the relay coil 23, so the relay contact 22 is opened and the heater 10 is not energized. Therefore, lighting of the first light emitting display element 40 is as follows:
The heater is displayed in the "off" state, where no power is being applied.

Next, when the operating device 1 is operated to close the switch 30, only the second output terminal 37 becomes low level, and the second light emitting display element 41 lights up. Also,
Since the output of the second output terminal 37 is at a low level, the potential at the connection point between the resistor 46 and the temperature sensing element 2 decreases, and the potential at the inverting input terminal 45 of the comparator 3 becomes lower than the potential at the non-inverting input terminal 51. The output of comparator 3 becomes high level. Therefore, transistor 52
is driven, current flows through the relay coil 23, and the relay contact 22 closes, so that the heater 10 is energized and the temperature of the base 11 rises. As the temperature of the base 11 increases, the resistance value of the temperature sensing element 2 decreases,
When the potential of the inverting input terminal 45 of the comparator 3 and the potential of the non-inverting input terminal 51 are reversed, the output of the comparator 3 is inverted and becomes a low level, and the power supply to the heater 10 is stopped. As a result, temperature sensing element 2
When the resistance value becomes high, the heater 10 is energized again. By repeating this operation, the temperature of the base 11 is maintained at the first predetermined temperature _T1 . That is, when the second light emitting display element 41 lights up, the set temperature is set to the first predetermined temperature _T1 . The resistance value R _TH1 of the temperature sensing element 2 at this time is
It is determined by the following formula.

R _TH1 = R ₄₆ / R ₄₉ / R ₅₀ In addition, R ₄₆ , R ₄₉ and R ₅₀ are resistors 46 and 4, respectively.
The resistance values of 9 and 50 are shown. Next, when the operating device 1 is operated to close the switch 30, the third output terminal 3
8 becomes low level, the third light emitting display element 42 lights up, and the temperature of the base 11 is maintained at the second predetermined temperature _T2 . That is, when the third light emitting display element 42 lights up, the set temperature has been set to the second predetermined temperature _T2 . The resistance value R _TH2 of the temperature sensing element 2 at this time is determined by the following equation.

R _TH2 = R ₄₇ · R ₄₉ /R ₅₀ Note that R ₄₇ is the resistance value of the resistor 47. As described above, by operating the operating device 1, the set temperatures are sequentially switched, and each predetermined temperature T ₁ ,
The relationship between T ₂ and T ₃ is determined by the relationship between the resistance values of the resistors 46, 47, and 48, so R ₄₆ > R ₄₇ >
By setting _R48 , the temperature of the base 11 is sequentially switched to low temperature, medium temperature, and high temperature, and at the same time, the light emitting display elements corresponding to each temperature are turned on.

Next, the operation of appropriate temperature notification will be explained with reference to FIGS. 3 and 5.

Initially, when the power is turned on, the thyristor 56 is off, so the transistor 65 is off, and the collector of this transistor 65 and the capacitor 67
transistor 6 connected to the base via
9 is in the on state. Since the collector of the transistor 69 and the base of the transistor 72 are connected, when the transistor 69 is on, the transistor 72 is turned off and the sounding body 8 is not driven.

When the switch 30 is closed to set the temperature, the base potential of the transistor 57 becomes high and the transistor 57 is turned off. Then, even if current was flowing through the thyristor 56 (latched state), the transistor 57 is turned off, so that the current flowing through the thyristor 56 becomes equal to or less than the holding current, and the latched state is released. (By setting the resistor 64 to a sufficiently large resistance value, the base current of the transistor 65 can be made equal to or less than the holding current of the thyristor 56.) After setting the temperature, when the temperature of the base 11 reaches the set temperature, the comparator When the output level of the transistor 3 changes from high level to low level and the transistor 52 is turned off, a differential pulse is generated at the gate of the thyristor 56 by the capacitor 55, and the thyristor 56 is turned on and becomes in a latched state. At this time, the thyristor 56 is turned on and at the same time the transistor 65 is also turned on, so that the monostable multivibrator 7 operates and drives the sounding body 8 for a certain period of time. In other words, the output 71 of the monostable multivibrator 7 is normally at a high level, but when the thyristor 56 is turned on from off, the monostable multivibrator 7 is driven, the transistor 69 is turned off, and the sounding element 8 is turned on. The driving transistor 72 is turned on for a certain period of time. The relationship between the temperature of the base, the on/off state of the thyristor 56, and the on/off state of the sounding body 8 is shown in FIG.

In this way, the iron of the present invention drives the sounding element for a certain period of time when the temperature of the base reaches the set temperature to convey to the auditory sense that the temperature has reached the appropriate temperature. Until the temperature setting is changed, it remembers that the temperature is at the appropriate temperature and does not inadvertently drive the sounding element. Users do not need to pay attention to the blinking indicators of the lamps attached to both ends of conventional heaters, and in other words, there is no need to waste time watching the lamps turn on and off, or turn off and turn on. When the temperature reaches the desired temperature, the iron makes a sound to let you know that it has reached the appropriate temperature, making it safe.

[Brief explanation of the drawing]

Fig. 1 is a block diagram schematically showing an iron showing an embodiment of the present invention, Fig. 2 is a partially cutaway sectional view of the iron, Fig. 3 is an electric circuit diagram thereof, and Fig. 4 is an electric circuit thereof. FIG. 5 is a block diagram of a ring counter with a preset function in FIG. 1... Operating device, 2... Temperature detection element, 3...
Comparator, 4...power control element, 5...differentiation circuit,
6... Latch circuit, 7... Monostable multivibrator, 8... Sound generator, 9... Latch release circuit.

Claims (1)

[Claims] 1. An operating device for arbitrarily setting the temperature of the base;
A temperature detection element that detects the temperature of the base, a comparator that compares the output of this temperature detection element with the temperature set by the operating device, and a power control element that controls energization to the heater based on the output of this comparator. and a differentiating circuit connected to the output of the comparator,
A latch circuit driven by the differentiating circuit, a monostable multivibrator driven by the output of the latch circuit, a sounding body driven by the output of the monostable multivibrator, and a latch circuit driven by the operating device. The iron is equipped with a latch release circuit for releasing the latch state of the circuit, and is configured to drive the sounding body for a certain period of time to notify the arrival when the temperature of the base reaches the set temperature.