JPS5820240Y2 - Dryer with drying end detection - Google Patents

Description

[Detailed description of the invention] The invention detects the resistance change between at least one pair of electrodes, which changes depending on the degree of dryness of the clothes, and automatically stops the clothes drying means when a predetermined resistance value is reached. The present invention relates to a dryer with drying end detection, which prevents malfunction of dryness detection by efficiently bringing clothes into contact with electrodes with appropriate contact pressure.

Conventional dryers with end-of-drying detection include those in which an electrode part is provided on the inner circumferential wall of the approximately cylindrical rotating part of the drum;
Some models have a plurality of electrode parts provided on the rear wall fixing part of the drum along the rotational direction of the drum.

However, in the former case, it is the rotating part of the drum.

Since the electrodes are attached to the inner circumferential wall of the approximately cylindrical rotating part, a sliding part is always required to detect the resistance value of the electrode and take it out as input to the circuit.As a result, the durability of the sliding part must be considered. In the latter case, the electrodes installed on the rear wall of the drum are almost flat, so there is a low probability that clothing will come into contact with the electrodes due to transfer, or It is sometimes difficult to count the pressure sufficiently, and as a result, the detection circuit malfunctions when the drying rate is low, and the detection of the end of drying is often unsatisfactory.

The present invention solves the above-mentioned conventional drawbacks, and one embodiment thereof will be described below with reference to the accompanying drawings.

In the figure, reference numeral 1 denotes an outer casing of a clothes dryer. Inside the outer casing 1 is a drum 4 composed of a substantially cylindrical rotating part 2 and a rear wall fixing part 3, which is a fixed part. An exhaust fan 6 that rotates within a fan case 5 is provided behind the rear wall fixing part 3.

Reference numeral 7 designates a motor, and a drum rotation pulley 8 and a fan rotation pulley 9 are respectively fixed to the motor shafts 7' at both ends, and the rotation of the motor 7 is transmitted to the drum 4 via the drum rotation pulley 8 and the flat belt 10. Along with this, the fan rotation pulley 9
, is also transmitted to the exhaust fan 6 via the fan belt 11 and the fan pulley 12.

Reference numeral 13 denotes a plurality of baffles fixed to the inner circumferential wall of the substantially cylindrical rotating portion 2 of the drum 4, and the baffles 13 stir and roll the clothes 14 inside the drum 4.

Reference numeral 15 denotes an intake wind tunnel, in which external air is sucked in from the front suction port 16 as shown by the arrow in FIG. This hot air is sucked into the drum 4 through a hot air suction hole 18 provided on the front surface of the drum 4 and dries the clothes 14.

The hot air and the moisture coming out of the clothes 14 pass through the fan case 5 through the hot air exhaust hole 19 provided in the rear wall fixing part 3, and are exhausted to the outside of the device main body 1 through the exhaust port 20.

21 is a filter that collects dust generated from clothing;
22 is a filter cover, 23 is a door that opens and closes the clothes input port 23a, 24 is a front sliding member that receives the drum 4,
24a is a rear sliding member provided on the outer edge of the rear wall fixing portion 3, 25 is a hot air sealing material, and 26 is an installation leg.

27 and 27' are a pair of electrodes arranged substantially parallel to each other along the rotational direction of the drum 4, that is, the direction of arrow C in FIG.
28 is an insulating base for fixing electrodes 27 and 27';
This insulating base 28 is provided below the rear wall fixing part 3.

As shown in FIG. 4, a tangent line in the radial direction of the drum 4 connecting the surfaces of the electrodes 27 and 27', that is, the electrodes 27.
27' in the lateral direction x-x' and the vertical projection plane a of the drum 4
The inclination angle α with respect to -a' is configured to be 5 to 20 degrees.

That is, in the transverse direction of the electrodes 27, 27', the electrodes 27, 27' are inclined so as to become lower from the rotation center side of the drum 4 toward the outer circumference.

Therefore, the relationship between this angle of inclination α° and the drying rate of the clothes at the time when the detection circuit was activated was as shown in FIG. 6a.

That is, the resistance of the clothing 14 is detected by the electrodes 27 and 27',
When extracting output, the most important thing is that the greater the contact pressure when clothing comes into contact with the electrode, the more stable the output can be obtained.As a result, there are fewer malfunctions of the detection circuit, and a higher drying rate can be obtained. That's what it means.

In this case, as shown in FIG. 4, the clothing 14 is rolled by the rotation of the baffle 13 and lifted upward by a force Fa as shown by the arrow in FIG. Fasinα° perpendicular to 27.27'
A component force is generated.

Therefore, as a result, the contact pressure of the clothing 14 to the electrodes 27, 27' is increased, and a more stable output can be obtained.

In addition, when α>20°, the electrodes 27 and 27' are connected to the clothing 1
4, and thus the transfer of the clothing 14 is not carried out smoothly, and as a result, it becomes impossible for the damp clothing located inside to come into contact with the electrodes 27, 27'. Overall, the drying rate will be poor when the detection circuit is activated.

Further, when α<5°, the drying rate is poor because the clothing 14 and the electrodes 27, 27' are not effectively contacted.

On the other hand, as shown in FIG. 5, an inclination angle β is set between the longitudinal direction Y-Y' of the electrodes 27, 27' and the vertical projection plane a-a' of the drum 4.

That is, in the longitudinal direction of the electrodes 27, 27', the inclination angle β is set to be higher along the rotational direction of the drum 4.

β is 5 to 20°. With this configuration, the clothing 14 receives a force Fb in the direction of rotation of the drum 4, that is, in the direction of arrow E in FIG. 5, similar to the above-mentioned inclination angle α.

At this time, a component force Fbsinβ° acts in the direction perpendicular to the electrodes 27, 27', resulting in the effect of increasing the contact pressure.

As for the relationship between this angle of inclination β° and the drying rate of the clothes at the time when the detection circuit was activated, the results shown in FIG. 6 were obtained.

The reason why β is set in the range of 5 to 20° is the same as the reason for setting the range of α above.When β>20°, the clothing acts as a resistance to transfer, and when β<5°, The contact between the clothing and the electrode is not good.

Also, the electrode 27°27' with respect to the vertical projection plane of the drum 4
By combining the inclination angles α° and β°, the contact pressure of the clothing 14 on the electrode surface can be adjusted to Fasinα
'0Fbsinβ°, so the effect becomes even more pronounced.

Furthermore, if either angle is set to 20 degrees or more, the transfer of the clothes will be hindered, and the performance will deteriorate on the contrary.

In addition, FIG. 6C shows the relationship between the drying rate during detection operation and β° when α° is used as a parameter, and FIG. 6d shows the relationship between β° and
The relationship between the contact pressure on the electrodes and the current generated between the electrodes when wearing the same clothing is shown.

Figure 7 shows an example of the basic configuration of the dryness detection circuit, where 29 is an isolation transformer for obtaining low voltage from the power supply section, and 30 is an isolation transformer that converts the low voltage AC obtained from the isolation transformer 29 into DC. 31 is a pair of electrodes 2
A voltage dividing resistor 32 is connected in series with 7 and 27', and 32 is a voltage dividing resistor 32 which is used when the contact resistance of the pair of electrodes 27, 27' reaches a predetermined resistance value, that is, the current between the electrodes 27, 27' reaches a predetermined level. This is a detection output control section for activating the relay 33 when the threshold is reached.

Further, the relay 33 is configured to operate in conjunction with a switch 34, and when the relay 33 is activated, the switch 34
The input to the motor 7 and the heater 17 is stopped by turning off the power.

This causes the drying device to stop.

As is clear from the above embodiments, according to the present invention, at least one pair of electrodes provided on the fixed portion of the drum are arranged substantially parallel to each other along the rotation direction of the drum, and with respect to the vertical projection plane of the drum. In the short direction of the electrode, the slope becomes lower from the rotation center side toward the outer periphery of the drum, and in the longitudinal direction of the electrode, it slopes so that it becomes higher along the rotation direction of the drum, The electrodes protrude three-dimensionally into the drum, increasing the contact pressure when clothing comes into contact with the electrodes, and as a result, a more stable output signal can be extracted than between the electrodes. It is possible to accurately detect the end of drying.

[Brief explanation of drawings]

Fig. 1 is a side sectional view of a clothes dryer showing an embodiment of the present invention, Fig. 2 is a front sectional view of the drum of the dryer, Fig. 3 is a partial perspective view of Fig. 2, and Fig. 4 is a view in the direction of arrow A in FIG. 3, FIG. 5 is a view in the direction of arrow B in FIG. 3, and FIG. The figure shows angle β. FIG. 6C is a graph showing the relationship between the angles β° and α° and the drying rate of clothing when the dryness detection circuit is activated. FIG. 6d
7 is a graph showing the relationship between the contact pressure of clothes to the electrodes and the current generated between the electrodes, and FIG. 7 is a circuit diagram for detecting the end of drying of the same dryer. 2... Rear wall fixing part, 3... Approximately cylindrical rotating part, 4... Drum, 7... Drive device (
motor), 13...baffle, 27.27'.
····electrode.

Claims (1)

[Scope of utility model registration request] a drum comprising a fixed part provided with at least a pair of electrodes and a substantially cylindrical rotating part pivotally supported by the fixed part; a plurality of baffles provided on the inner circumferential wall of the substantially cylindrical rotating part of the drum; It is equipped with a drive device that rotates and a device that detects a resistance change between the electrodes that changes depending on the degree of dryness of the clothes, and stops the clothes drying means when a predetermined resistance value is reached, and the electrodes are connected to the drum. The electrodes are arranged substantially parallel to the rotational direction of the drum, and the longitudinal direction of the electrodes is arranged so that the width of the electrodes becomes lower from the rotation center side toward the outer periphery of the drum in the transverse direction of the drum with respect to the vertical projection plane of the drum. A dryer with drying end detection that is tilted upward along the direction of rotation of the drum.