JPH0246240B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electronically controlled iron.

Temperature detection in conventional electric irons generally uses a bimetal, and when setting the temperature, by directly rotating a thermo knob, etc., the intervening member connected to the bimetal is mechanically moved by a screw or cam plate. The displacement dimension was converted into a rotation angle, and the position was adjusted to the fiber name temperature provided on the orbit of the thermo knob. Therefore, due to the need for space to accommodate the thermo knob and other components that have a circular trajectory, the thermo knob was installed at the 8th position.
As shown in FIG. 8A, it is necessarily located at the center of the body of the handle body 50, or at the tip of the handle body 50, as shown in FIG. 8B. In addition, in FIGS. 8A and 8B, 51 is a base, 52 is a cover, 53 is a water tank, and 54 and 55 are thermo knobs, respectively.

However, especially in the former case, since the position is directly below the grip part of the handle body 50, it is difficult to align the position because it is hidden from the hand holding it, and it is difficult to operate it with one hand. Although the latter does not have the same disadvantages as the former, it is difficult to operate with one hand, which is the same as the former.

On the other hand, ironing finishing work is done using synthetic fibers, wool,
The best way to use it is to gradually increase the temperature from a low temperature to a high temperature using cotton, linen, and steam, and the number of temperature adjustments required was surprisingly large, causing inconvenience each time.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an electronically controlled iron that can perform highly accurate temperature control and can easily perform temperature setting operations at hand.

The electronically controlled iron of the present invention has an output switching circuit that sequentially switches the output state each time the switch is turned on and off, and detects the selected resistance and base temperature according to the output state of the output switching circuit. 2 of the bridge circuit including the temperature sensing element
The output is compared with a comparator, and the power control element is turned on and off depending on the output level of the comparator to control the energization of the heater, and the indicator is activated depending on the output state of the output switching circuit. By this,
In a device that accurately controls the temperature of the base and displays the set temperature to make it easier for the user to understand, the temperature sensing element, display, and power control element are individually arranged. By taking advantage of the advantage of being able to use a thermostat and the ability to use an electrical on/off switch in place of a conventional thermoswitch, the switch's operating knob is placed near the grip of the handle, making it easier to set the temperature at hand. It was designed to be carried out in the following manner.

An electronically controlled iron according to an embodiment of the present invention will be explained based on FIGS. 1 to 7.

FIG. 1 shows a block diagram of an electronically controlled iron. In the figure, 1 is a base portion of the iron, 2 is a temperature detection element for detecting the temperature of the base portion 1, and 3 is an output switching circuit including a ring counter and the like. This output switching circuit 3 switches the resistance value of one side of the bridge circuit based on the output of the ring counter, and also drives a set temperature display 8 to display the set temperature. A switch 4 operates the output switching circuit 3, and shifts the output of the output switching circuit 3 every time it is turned on or off. 5 is a comparator that compares the two outputs of the bridge circuit including the temperature detection element 2 and the resistance selected by the output of the output switching circuit 3, and drives the power control element 6 with the output to control the energization of the sheathed heater 7. The temperature of the base portion 1 is maintained at a predetermined set temperature. That is, by turning the switch 4 on and off, the temperature of the base portion 1 can be maintained at an arbitrary set temperature, and the set temperature is indicated by the set temperature indicator 8.

FIG. 2 shows a specific electrical circuit diagram of the electronically controlled iron. In the figure, reference numeral 9 denotes an AC power source, to which a series circuit of the sheathed heater 7 and a normally open relay contact 10a is connected. This relay contact 10a closes when current flows through a relay coil 10b, which will be described later, and energizes the sheathed heater 7. Further, a series circuit of a resistor 11 and a capacitor 12 is connected to the AC power source 9. This capacitor 12 serves as a constant voltage DC power source for a control circuit to be described later. 13 is a ring counter with a preset function connected in parallel to the capacitor 12;
One end 13a is connected to one end of the capacitor 12,
The other end 13b is connected to the other end of the capacitor 12 and kept at ground potential. Reference numeral 4 denotes a switch which is opened and closed by operating an operating means to be described later, and is connected between one end of the capacitor 12 and the first input terminal 13c of the ring counter 13 with a preset function. 14 is a ring counter 13 with preset function.
A resistor 15 is connected between the second input terminal 13d and the third input terminal 13e of the ring counter 13, and a capacitor 15 is connected to the third input terminal 13e of the ring counter with preset function 13 and the other end of the capacitor 12. 14 and capacitor 15 determine the time constant of the clock pulse for switching the output of the ring counter 13 with preset function. 13f, 13
g, 13h and 13i are the first output terminal, second output terminal, third output terminal and fourth output terminal, respectively, of the ring counter with preset function 13, and these output terminals 13f, 13g, 13
h and 13i are light emitting display elements 16a and 16, respectively.
b, 16c, and 16d to one end of a resistor 17, and the other end of this resistor 17 is connected to a capacitor 1.
Connected to one end of 2. The circuit diagram shows four light emitting display elements 16a, 16b, 1 as an example.
6c and 16d constitute a set temperature display.

The temperature sensing element 2 has one end connected to one end of the capacitor 12 and the other end connected to the inverting input terminal 5 of the comparator 5.
a, and is connected to the second output terminal 13g of the ring counter 13 with a preset function via a resistor 18, and to the third output terminal 13h of the ring counter 13 with a preset function via a resistor 19.
Furthermore, it is connected via a resistor 20 to a fourth output terminal 13i of a ring counter 13 with a preset function. 21 and 22 are resistors connected in series, and this series circuit is connected in parallel to the capacitor 12. The connection point between the resistor 21 and the resistor 22 is connected to the non-inverting input terminal 5b of the comparator 5. 23 is a transistor connected in series to the relay coil 10b, and the series circuit of this relay coil 10b and the transistor 23 is connected to the capacitor 1.
2 are connected in parallel. The output of the comparator 5 is inputted to the base electrode of the transistor 23 via the resistor 24, and when the output of the comparator 5 is at H level, it becomes conductive and current flows through the relay coil 10b, closing the relay contact 10a. . 25 is the relay coil 10
This is a diode connected in parallel to b.

Next, the operation of this circuit configuration will be explained. First, a ring counter 13 with a preset function is constructed based on the specific block diagram shown in FIG.
Explain the operation. 26 is a ring counter, and when a voltage is applied to the terminal 13a as shown in FIG. It is set to L level as shown in C. Note that at this time, the second output circuit 26b, the third
Both the output circuit 26c and the fourth output circuit 26d have an open collector type configuration, and the respective outputs of the second output terminal 13g, the third output terminal 13h, and the fourth output terminal 13i are as shown in FIG. 4D, E, As shown in F, both become H level.

Next, the switch 4 is closed and the first input terminal 1
3 input is at H level, the second input terminal 13
d and a resistor 1 connected to the third input terminal 13e.
The oscillation circuit 28 oscillates according to a time constant determined by the values of the capacitor 4 and the capacitor 15, and outputs a clock pulse as shown in FIG. 4B. When this clock pulse is input to the ring counter 26, the second output circuit 26b is driven, and only the output of the second output terminal 13g becomes L level as shown in FIG. 4D, and the other output terminals 13f, 13h, 13i
The output becomes H level as shown in FIG. 4C, E, and F.

When the next clock pulse is further input to the ring counter 26, the third output circuit 26c is driven, and only the output of the third output terminal 13h becomes L level as shown in FIG. 4E.

When the next clock pulse is input to the ring counter 26, the fourth output circuit 26d is driven.
Only the output of the output terminal 13i becomes L level as shown in FIG. 4F. Furthermore, when the next clock pulse is input to the ring counter 26, the first output circuit 26a is driven, and only the output of the first output terminal 13f becomes L level as shown in FIG. 4C. Repeat the same below.

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

First, when the AC power supply 9 is connected, the first output terminal 13f of the ring counter 13 with preset function is connected.
The output becomes L level, and the first light emitting display element 16
Current flows through a and it lights up. second output terminal 13g,
Since the outputs of the third output terminal 13g and the fourth output terminal 13i are at H level, the potential at the connection point between the temperature sensing element 2 and the resistor 18 is high, and therefore the input of the inverting input terminal 5a of the comparator 5 is non-conductive. Inverting input terminal 5
The output of comparator 5 becomes L level, which is higher than the input of b, and the transistor 23 is not conductive and no current flows through the relay coil 10b, so the relay contact 10a is opened and the sheathed heater 7 is not energized. Therefore, the lighting of the first light emitting display element 16a indicates the "off" state in which the sheathed heater 7 is not energized.

Next, when the operating means is operated to close the switch 4, only the output of the second output terminal 13g becomes L level, and the second light emitting display element 16b lights up.
Furthermore, since the output of the second output terminal 13g is at the L level, the potential at the connection point between the resistor 18 and the temperature sensing element 2 decreases, and the input of the inverting input terminal 5a of the comparator 5 becomes lower than the input of the non-inverting input terminal 5b. The output of the comparator 5 becomes H level. Therefore, the transistor 23 becomes conductive, current flows through the relay coil 10b, and the relay contact 10a closes, so that the sheathed heater 7 is energized and the temperature of the base portion 1 increases. As the temperature of the base portion 1 increases, the resistance value of the temperature sensing element 2 decreases, and when the input level of the inverting input terminal 5a and the input of the non-inverting input terminal 5b of the comparator 5 are reversed, the output of the comparator 5 is inverted. Then, it becomes L level, and the power supply to the sheathed heater 7 is stopped.
As a result, when the resistance value of the temperature sensing element 2 becomes high, the sheathed heater 7 is energized again. By repeating such operations, the temperature of the base portion 1 is maintained at the first predetermined temperature _T1 . That is, when the second light emitting display element 16b lights up, it means that the set temperature has been set to the first predetermined temperature _T1 . The resistance value R _TH1 of the temperature sensing element 2 at this time is determined by the following equation.

R _TH1 = R ₂₁・R ₁₈ /R ₂₂ Note that R ₁₈ , R ₂₁ , and R ₂₂ are resistors 18 and 2, respectively.
The resistance values of 1 and 22 are shown.

Next, when the operating means is operated to close the switch 4, only the output of the third output terminal 13h becomes the L level, the third light emitting display element 16c lights up, and the temperature of the base part 1 reaches the second predetermined level. Temperature T ₂
is maintained. That is, the third light emitting display element 16
When c lights up, it means that 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 ₂₁ · R ₁₉ /R ₂₂ Note that R ₁₉ is the resistance value of the resistor 19.

Further, when the switch 4 is closed, only the output of the fourth output terminal 13i becomes L level, the fourth light emitting display element 16d lights up, and the set temperature is set to the third predetermined temperature _T3 . The resistance R _TH3 of the temperature sensing element 2 at this time is determined by the following equation.

R _TH3 = R ₂₁ · ₂₀ / R ₂₂ Note that R ₂₀ is the resistance value of the resistor 20.

As described above, the set temperature is sequentially switched by operating the operating means, and the relationship between the predetermined temperatures T ₁ , T ₂ , and T ₃ is as follows:
Since it is determined by the relationship between the resistance values R ₁₈ , R ₁₉ , and R ₂₀ , by setting R ₁₈ > R ₁₉ > R ₂₀ , the temperature of the base portion 1 can be sequentially switched to low temperature, medium temperature, and high temperature. become.

FIG. 5 is a partially cutaway side view of this electronically controlled iron, FIG. 6 is a sectional view thereof, and FIG. 7 is a perspective view of the iron in use. In FIGS. 5 to 7, 1 is the base of the iron, 2 is a temperature sensing element that is in close contact with the inner surface of the base, 30 is a cover that covers the upper part of the base, and 31 is a cover 30.
It is a heat shield plate that covers the upper and rear sides with a certain gap.The cover 30 is installed by passing the cover 30 through the boss 31a provided on the lower surface and tightening the screws 32.
Fixed. 33 is a handle body with an open bottom surface,
The locking pawl 31b at the rear of the heat shield plate 31 is engaged with a lock hole (not shown) provided at the rear opening edge, and the heat shield plate 31 is fitted into a boss 33a provided downwardly protruding from the inner wall surface of the body. It is fixed to the heat shield plate 31 by tightening the screw 34 through the through hole 31c. 35
is a handle back cover that closes the rear opening of the handle body 33. By tightening a screw 36 to a boss 33b on the inner wall surface of the rear leg of the handle body 33 through a boss 35a provided on the inner surface, the handle back cover 35 closes the handle. It is fixed to the body 33. 37 is a handle body 33, a heat shield plate 31, and a handle back cover 3
The control board is placed in a space formed by Other short parts are mounted on the top so that they are located in the space inside the fuselage. Reference numerals 38 and 39 indicate auxiliary heat insulating plates, which are interposed between the heat shield plate 31 and the control board 37 to form a multi-layer heat insulating space, and the heat shield plate 31 and the auxiliary heat insulating plates 38 and 39 are placed opposite each other. At corresponding positions on the surface, there are concave and convex fitting parts 31d, 38a, 38b, respectively, for securing heat insulation space and mutual positioning.
39a is provided, and a protrusion 39b that supports the control board 37 is provided on the upper surface of the uppermost auxiliary heat insulating board 39, and this protrusion 39b and a downward step part 33d provided inside the handle body 33 support the control board 37. It has come to be held in place. Reference numeral 40 denotes a switch board, which is disposed within the grip portion of the handle body 33 and fixed with a screw 41, on which the switch 4 is mounted. Reference numeral 42 denotes an operation knob for operating the switch 16, which protrudes outward from the upper surface of the grip portion of the handle body 33.

43 is a water tank attached to the front part of the handle body 33, and a button 44 for switching between steam and dry is located at the top.
A nozzle 4 for supplying water to the base portion 1 is provided below the steam/dry switching button 44.
5 is formed, and its opening/closing is controlled by moving the operating stick 46 up and down. When the water supply nozzle 45 opens, the water in the water tank 43 drips into the vaporization chamber 47 of the base part 1 to generate steam, which is ejected from the steam hole formed in the base part 1. Also,
The water tank 43 can be removed from the handle body 33 by operating a lock knob 48 provided near the grip portion of the handle body 33.

Further, the light emitting display elements 16a to 16d are connected to the handle body 3.
It is exposed to the outside through a through hole in the upper surface of the body of No. 3.

In this way, in this embodiment, the desired set temperature can be easily and accurately obtained by simply turning on and off the switch 4, and the temperature control accuracy is high. 8, so it is easier to distinguish at a glance compared to the conventional bimetal type, and when the power cord is connected, one of the light emitting display elements 16a to 16d is always lit. , it is possible to provide a visual notification function for forgetting to turn off the power. Further, since the switch 4 is disposed within the grip portion of the handle body 33, and its operation knob 44 is projected outward from the upper surface of the grip portion, temperature setting can be easily performed at hand.
In other words, since only the compact operation knob 42 can be installed in any position, the operator can freely select a position in front of the handle grip, which has traditionally been considered an ideal position, where it can be easily operated with one finger while being held. In addition, the design has become simpler, especially with the water tank 4 in the front of the handle.
In the case of the cassette-type steam iron with 3, it was not possible to provide a handle other than the center part of the body, but this also made the grip part thicker so that the temperature at the hand can be set without adversely affecting other aspects such as ease of use. became possible.

As described above, the electronically controlled iron of the present invention includes a base portion with a built-in heater, a temperature sensing element attached to the base portion to detect the temperature of the base portion, and a temperature sensing element fixed above the base portion. A handle body, a switch, an output switching circuit whose output state is switched by operating the switch, a plurality of temperature setting resistors selected according to the output state of the output switching circuit, the temperature sensing element, and the temperature The first and second resistors that constitute the setting resistor and the bridge circuit
, a comparator for comparing the two outputs of the bridge circuit, and a display having a plurality of display elements, and the operation part of the switch is provided on the outer surface of the handle body near the grip part, so that high precision can be achieved. This has the advantage of being able to control the temperature and easily setting the temperature by hand.

[Brief explanation of drawings]

Fig. 1 is a block diagram of an electronically controlled iron according to an embodiment of the present invention, Fig. 2 is a specific circuit diagram thereof, Fig. 3 is a specific block diagram of its main parts, and Figs. 4 A to F are waveforms of each part thereof. Figure 5 is a partially cutaway side view showing the configuration of this electronically controlled iron, Figure 6 is a sectional view, Figure 7 is a perspective view of the iron in use, and Figures 8A and B are conventional irons. FIG. 1...Base part, 2...Temperature detection element, 3...
Output switching circuit, 4... switch, 5... comparator,
6... Power control element, 7... Sheathed heater, 8...
...Indicator, 18-22...Resistor, 30...Cover, 31...Heat shield plate, 33...Handle body, 42...
Operation knob.

Claims (1)

[Claims] 1. A base portion with a built-in heater, a temperature detection element attached to the base portion to detect the temperature of the base portion, a handle body fixed above the base portion, and a switch; A bridge circuit is formed by an output switching circuit whose output state is switched by the operation of this switch, a plurality of temperature setting resistors selected according to the output state of this output switching circuit, the temperature sensing element and the temperature setting resistor. a comparator for comparing the two outputs of the bridge circuit, and a display having a plurality of display elements, and the operation part of the switch is located near the grip part of the handle body. Electronically controlled iron on the outside. 2. The electronically controlled iron according to claim 1, wherein a switch board on which the switch is mounted is disposed in an internal space near a grip portion of the handle body. 3. The electronically controlled iron according to claim 1, wherein the switch is disposed in a recess formed on the outer surface of the handle body near the grip portion.