JP4952833B2 - Clothes dryer - Google Patents

Description

  The present invention relates to a clothes dryer for storing clothes in a drum and drying, and further to a clothes washer / dryer having functions of washing, rinsing and dewatering.

  Conventionally, in a clothes dryer or a clothes washing dryer having a drying function, various control methods have been proposed in order to shorten the drying operation. Among them, as the flow control of the drying air, in order to suppress the number of times the heater is started and stopped, the number of rotations by the blower fan drive motor is increased as the exhaust temperature from the drum reaches a predetermined target temperature ( For example, there is Patent Document 1). In addition, it is equipped with a heat pump device and an air circulation air passage, and the air volume is controlled to release heat to the outside of the circulation air passage for the purpose of excessively increasing the temperature of the refrigerant and the circulation air and overloading the compressor. Some of them (for example, Patent Document 2).

JP 2004-344238 A JP 2004-329755 A

  The conventional proposal is for the purpose of suppressing the start and stop of the heater and the compressor, and increases the rotational speed of the blower fan from the middle of the drying process and increases the air volume. However, in the drying process, the garment swells and the ventilation resistance increases as the dryness increases. Moreover, the clogging of the lint filter that captures the lint scattered from the clothing also proceeds, and the ventilation resistance increases from that point. When the rotational speed of the blower fan is increased in such a situation, the generated aerodynamic noise also increases. Since the drying process takes a long time, low noise is very important. In order to perform control to increase the rotation speed of the blower fan drive motor from the middle of the drying process while keeping the noise at a certain level in order to maintain the comfort of the noise in the environment of drying, the blower fan drive motor in the initial stage of drying Therefore, there is a problem in that the drying capacity cannot be sufficiently obtained.

  The present invention has been made to solve the above-described problems, and has an object of obtaining a clothes dryer and a clothes washing and drying machine having a high drying capacity without impairing the noise environment at the installation site. It is.

  A clothes dryer according to the present invention includes a water tank, a drum disposed in the water tank, an air passage for flowing warm air into the drum, a blower fan that sends out warm air in the air path, A clothes dryer comprising: a control unit that controls the number of rotations of the blower fan; and an exhaust temperature sensor that detects a temperature of air exhausted from the drum, and drying clothes stored in the drum, The control unit controls the rotational speed of the blower fan at the start of drying so that the rotational speed of the blower fan is greater than the rotational speed of the blower fan at the end of drying. The timing when the drying is finished is controlled based on the temperature detected by the exhaust temperature sensor.

  In the clothes dryer according to the present invention, the rotational speed of the blower fan at the start of drying is controlled to be larger than the rotational speed of the blower fan at the end of drying. The air volume at the start of drying can be increased while holding it, and the drying capacity can be increased.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a configuration of a clothes dryer according to Embodiment 1 of the present invention. In the same figure, 1 is a main body, 2 is a water tank, 3 is a drum for storing clothes to be dried, and a small number of small holes that allow airflow to pass through the cylindrical surface and the side surface of the cylinder and also allow water to pass during drainage and dehydration. Is provided. 4 is a drum motor for rotating the drum, 5 is a blower fan for generating an airflow flowing in the drum, 6 is a heating device including a heating source such as an electric heater for raising the temperature of the air, 7 is a water tank air inlet, 8 is a water tank exhaust port, 9 is a lint filter that captures lint released from clothing, 10 is a dehumidifying device that removes moisture from high-humidity air containing moisture taken from clothing, 11 is a control unit, and blower fan 5 Control the number of revolutions. Reference numeral 12 denotes a main body ambient air temperature detection device, and reference numeral 13 denotes a drum exhaust air temperature detection device. The white arrow indicates the air flow.

  The operation of the clothes dryer configured as described above will be described. First, the flow of air will be mainly described. The temperature of the airflow generated by the action of the blower fan 5 rotating at the number of rotations controlled by the control unit 11 is increased by the heating device 6. The high temperature air whose temperature has risen passes through the water tank inlet 7 and enters the drum 3 in the water tank. The drum 3 is rotated by a drum motor 4 to stir the stored clothes. While being agitated, the clothing comes into contact with hot air and loses moisture. The air that has taken moisture from the clothes and has become highly humid passes through the water tank exhaust port 8 and is discharged from the drum 3 and the water tank 2. The exhausted air contains lint released from the clothing, and the lint is captured by the lint filter 9. Moisture taken from the clothing is dehumidified by the dehumidifier 10.

  Next, before explaining the rotational speed control of the blower fan 5 in the drying process, the heating period, the constant rate drying period, and the decremental drying period in which the drying process is subdivided into time series in which the dryness of the clothing progresses will be described. Keep it. The drying process proceeds in the order of the heating period, the constant rate drying period, and the decreasing rate drying period from the start of drying, and the drying is completed. In the heating period, most of the heat generated by the heating device 6 is spent on raising the temperature of the clothes, the drum 3 and the water tank 2. As the temperature of the clothes increases, the evaporation rate of moisture contained in the clothes increases. Next, in the constant rate dryer, the amount of heat input into the water tank, the heat of evaporation of the clothes, and the amount of heat released from the water tank 2 are substantially balanced, and the amount of change in the evaporation rate of moisture contained in the clothes is small. In the dry season, the amount of moisture contained in the clothing is small, and the clothing temperature rises. Note that these subdivided boundaries are not strictly separable.

Next, the ventilation resistance load applied to the blower fan 5 will be described. The clothing at the start of drying is in a compressed state by the dehydration process. In the heating period, the clothes are heated while being stirred and loosened in the drum. Since the loosened clothing has a large volume, the ventilation resistance inside the drum 3 is increased. Further, as drying progresses, lint is released from the clothing, and the ventilation resistance of the lint filter 9 that captures lint increases. This lint release increases with the drying of the garment and is most likely to be released during the rate of dryness. For these reasons, when the airflow resistance of the air passing from the blower fan 5 through the heating device 6, the drum 3, the lint filter 9, and the dehumidifying device 10 is constant, the drying process proceeds as shown in FIG. It rises with it. In particular, the increase in ventilation resistance in the heating period and the rate-decreasing drying period is larger than that in the constant rate dryer. The horizontal axis in FIG. 2 represents the dryness defined by the following equation.
Dryness (%) = 100 × ((clothing weight)) − (sufficiently dry clothing weight)) / (sufficiently dry clothing weight)
Usually, the dryness at the start of drying is 70% to 80%, and the dryness at the end of drying is 100%.

  Next, the rotation speed control of the blower fan 5 in the drying process will be described. In the clothes dryer of the present invention, the rotational speed of the blower fan is controlled to be high at the start of drying and low at the end of drying. The characteristics when the rotational speed of the blower fan 5 is controlled in this way will be described with reference to FIG. FIG. 3 shows an example of control in which three blower fan rotation speeds are set in the entire drying process, and the rotation speed is sequentially lowered. As the degree of dryness increases from the start of drying, aeration resistance increases as described above, so aerodynamic noise also increases. In the present invention, by controlling to reduce the rotational speed of the blower fan step by step, compared to the case where the rotational speed of the blower fan is constant throughout the drying process under the condition of a predetermined level or less required for aerodynamic noise, The blower fan speed can be set high until the blower fan speed is set at the end of the drying process.

  As described above, in the present embodiment, since the rotational speed of the blower fan at the start of drying is controlled to be higher than the rotational speed of the blower fan at the end of drying in the drying process, the air volume of the dry air is increased. Thus, a greater amount of heat can be input to the drum 3 under aerodynamic noise below a predetermined level, and as a result, the drying time can be shortened.

  FIG. 3 shows an example in which the number of rotations of the blower fan 5 is controlled in three steps. However, in the case of two steps as shown in FIG. When the noise level is set to a predetermined level or less, the air volume from the start of drying can be set high, and the effect of shortening the drying time can be obtained.

  The timing for controlling the blower fan speed will be described. Since aerodynamic noise is closely related to ventilation resistance, it is desirable to control the rotational speed of the blower fan in accordance with the rate of change in ventilation resistance. That is, it is preferable to perform control according to the heating period, the constant rate drying period, and the decreasing rate drying period. Although it is difficult to directly detect the degree of drying of clothes, there is a means for indirectly detecting as described below. The humidity of the air exhausted from the drum 3 decreases as the dryness increases. There is a method of detecting the humidity of the air exhausted from the drum 3 and controlling the rotational speed of the blower fan based on that value. At this time, the measured temperature data may be subjected to a process such as a moving average in order not to perceive a change in humidity. The correlation between the dryness of the clothes and the humidity of the air exhausted from the drum 3 is high, and the dryness of the clothes can be detected with high accuracy.

  Further, as another means for detecting the dryness of clothes and determining the rotational speed of the blower fan, there is a method of measuring the temperature and indirectly detecting the dryness to control the rotational speed of the blower fan. For example, the dryness of the clothes is detected from the difference between the air temperature supplied to the drum 3 and the air temperature exhausted from the drum 3, or the difference between the air temperature exhausted from the drum 3 and the air temperature around the main body. There is a way. At this time, the measured temperature data may be subjected to processing such as moving average in order not to perceive fluctuations in temperature change. In this case, since the sensor for measuring the temperature is less expensive than the sensor for measuring the humidity, the manufacturing cost of the product can be kept low. In FIG. 1, the structure provided with the main body surrounding air temperature detection apparatus 12 and the drum exhaust air temperature detection apparatus 13 is shown.

  Further, there is a method of controlling the operation time of each blower fan rotation speed by setting it in advance.

Embodiment 2. FIG.
In the second embodiment, a heat pump is used as means for heating air used for drying clothes. FIG. 5 shows the configuration of the clothes dryer in the second embodiment of the present invention. Parts having the same symbols as those of the first embodiment are the same components. In the figure, 14 is a compressor, 15 is a condenser, 16 is a refrigerant throttling device, 17 is an evaporator, 18 is a condensed refrigerant temperature detecting means, and further, a clothes dryness detecting means (not shown) is accommodated in the drum 3. A dry garment load amount detection means (not shown). The white arrow indicates the flow of air, and the black arrow indicates the flow of refrigerant in the heat pump device.

  Inside the main body 1, as a feature of the second embodiment, a compressor 14, a condenser 15, a refrigerant throttle device 16, and an evaporator 17 are installed, which are sequentially connected by a pipe line to constitute a heat pump. The air side is a path that flows into the condenser 15 again via the condenser 15, the blower fan 5, the water tank air inlet 7, the drum 3, the water tank exhaust outlet 8, the lint filter 9, and the evaporator 17. The control unit 6 not only controls the rotational speed of the blower fan 5 but also controls the operating frequency of the compressor 14 and the rotational speed of the drum 3.

  Next, the operation will be described. The operation is started at the drum rotation speed and the blower fan rotation speed set in advance based on the dry clothing load detected by the detection means. Next, the compressor 14 is driven. At this time, the compressor operating frequency is determined based on the main body ambient temperature, the dry clothing load, and the rotational speed of the blower fan detected in advance by the main body ambient temperature detector 12. During the drying process, the operating frequency of the compressor 14 is controlled so that the condensed refrigerant temperature detected by the condensed refrigerant temperature detecting means 18 falls within a preset temperature range. The rotational speed of the blower fan is controlled according to the clothes dryness detected by the clothes dryness detecting means. The blower fan rotation speed at the start of drying when the clothes dryness is low is controlled to be higher than the blower fan rotation speed at the end of drying when the dryness is high.

  The dry garment load amount can be detected by a method of detecting from the torque derived from the current value of the drum motor 4 or a method of detecting from the inertial rotational speed after rotational driving at a constant speed. As described in the first embodiment, the dryness of clothes is detected from the humidity of the air exhausted from the drum 3, the air temperature flowing out from the drum 3, the air temperature flowing into the drum 3, or the surroundings of the main body. There is a method to detect from the difference with air temperature.

  Next, it demonstrates along the flow of air. The air passing through the condenser 15 rises to about 65 ° C., and the air flowing into the drum through the water tank inlet 7 becomes about 60 ° C. After contacting the clothing and evaporating the moisture of the clothing, The temperature reaches 40 ° C., passes through the water tank exhaust port 8, and is then dehumidified and cooled in the evaporator 17. The temperature of the air in contact with clothing is about 90 ° C. when an electric heater is used as the heating source, but is lower when the heat pump condenser 15 is used as the heating source. Therefore, a higher air volume is required than when an electric heater is used to increase clothes drying capacity. When an electric heater is used, it is about 1 m 3 / min, whereas when a heat pump condenser 15 is used, 2 to 3 m 3 / min is required. In addition, the approximate air temperature shown here demonstrates in the constant rate drying period as an example.

  In the second embodiment, as in the first embodiment, the blower fan rotation speed at the start of drying with low clothes dryness is controlled to be higher than the blower fan rotation speed at the end of drying with high dryness. Therefore, while keeping the noise in the drying process at a predetermined level or less, a high air volume can be obtained from the start of drying to the middle of the drying process, and the drying time can be shortened. In Embodiment 2, since the heat pump condenser 15 having a temperature lower than that of the electric heater is used as the heating source as described above, the required air volume is high. For this reason, the ratio of aerodynamic noise to the total noise is high, and in the clothes dryer using the blower fan rotation speed control of the present embodiment, the effect of increasing the air volume and shortening the clothes drying time is further increased. Further, the increase in the air volume has an effect of suppressing the condenser refrigerant temperature, and the compressor frequency can be set higher. This means that the amount of heat input into the drum is further increased and the effect of shortening the clothes drying time is enhanced.

  FIG. 6 shows an example in the case of an air path configuration different from FIG. In the figure, 19 is a main body air supply port, and 20 is a main body exhaust port. Air is taken in from the main body air supply port 19 and is exhausted from the main body exhaust port 20 to the outside of the main body 1 via the condenser 15, the drum 3, the lint filter 9, and the evaporator 17.

  In such a configuration, since the temperature of the air flowing into the condenser 15 is stable regardless of the state of the heat pump, the state of the heat pump, that is, the operation of the compressor 14 can be stabilized, and the reliability of the operation Can increase the sex. In the case of this air passage configuration, the main body air supply port 19 and the main body exhaust port 20 are open to the outside of the main body 1, particularly in the case of FIG. Aerodynamic noise increases. Therefore, the ratio of aerodynamic noise to the total noise is higher, and in the clothes dryer using the blower fan rotation speed control of the present embodiment, the effect of increasing the air volume and shortening the clothes drying time becomes more remarkable. .

Embodiment 3 FIG.
In the third embodiment, the clothes dryer described in the first and second embodiments is added with washing, rinsing, and dehydrating functions to form a clothes washing and drying machine. In this case, since the effects of the first and second embodiments obtained as a clothes dryer can be obtained in the same manner, in the clothes washing and drying machine of the present embodiment, the noise in the drying process is less than the predetermined level. Thus, a high air volume can be obtained from the start of drying to the middle of the drying process, and the drying time can be shortened. In the case of a clothes washing and drying machine, the load of clothes can be detected before the start of washing, that is, when the clothes are dry. Therefore, when the rotation speed of the blower fan 5 or a heat pump is used, the compressor 14 is used. The frequency control can be performed with higher accuracy.

It is a figure which shows the structure of the clothes dryer which concerns on Embodiment 1. FIG. It is a figure which shows the dryness and ventilation resistance of clothing. It is a figure explaining the example of control of the ventilation fan rotation speed. It is a figure explaining the example of control of the ventilation fan rotation speed. It is a figure which shows the structure of the clothes dryer which concerns on Embodiment 2. FIG. It is a figure which shows another structure of the clothes dryer which concerns on Embodiment 2. FIG.

DESCRIPTION OF SYMBOLS 1 Main body 2 Water tank 3 Drum 4 Drum motor 5 Blower fan 6 Heating device 7 Water tank air supply port 8 Water tank exhaust port 9 Lint filter 10 Dehumidifier 11 Control part 12 Main body surrounding air temperature detection device 13 Drum exhaust air temperature detection device 14 Compression Machine 15 Condenser 16 Refrigerant throttle device 17 Evaporator 18 Condensed refrigerant temperature detection means 19 Main body air inlet 20 Main body exhaust port

Claims (2)

A water tank, a drum disposed in the water tank, an air passage for flowing warm air into the drum, a blower fan for sending warm air in the air passage, and a control for controlling the number of rotations of the blower fan A clothes dryer comprising: a section; an exhaust temperature sensor that detects a temperature of the air exhausted from the drum; and an ambient temperature sensor that detects an ambient air temperature, and drying clothes stored in the drum. ,
The controller controls the air flow based on the detected temperature difference between the exhaust temperature sensor and the ambient temperature sensor.
A clothes dryer characterized by controlling the timing of lowering the rotational speed of a fan from that at the start of drying to that at the end of drying. An intake air temperature sensor for detecting the temperature of air sucked into the drum;
The control unit controls the timing of lowering the rotation speed of the blower fan from that at the start of drying to that at the end of drying, based on a detected temperature difference between the exhaust temperature sensor and the intake air temperature sensor. The clothes dryer according to claim 1 .

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