JP2008183298A - Clothes dryer, and washing and drying machine provided with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a time spent until a refrigeration cycle becomes steady without raising costs. <P>SOLUTION: The clothes dryer includes: a compressor 35 driven by a motor; a heat pump device 51 composed by joining a heat emitter 36, a spinning means 37, and a heat absorber 38 with a pipe 39 so that a coolant circulates; a blast means 43 for sending air for drying; and coolant pressure detecting means for detecting pressure of the coolant. When the coolant pressure is lower than a prescribed value, control is performed so that the motor efficiency does not become maximum in order to increase an amount of heat generation from within the motor. The time spent until the refrigeration cycle becomes steady can be reduced without raising costs. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a clothes dryer used in a general household and a clothes dryer installed in a clothes dryer that performs only drying.

  Conventionally, as this type of clothes drying apparatus, there are those using a heater as a heat source, and those using a heat pump device as a heat source, but those using a heat pump device as a heat source are particularly useful when the ambient temperature is low. There is a problem that it takes time until the refrigeration cycle reaches a steady state as compared with the heat source.

  On the other hand, at least a part of the piping from the refrigerant pipe throttling means to the compressor is provided in the circulation air path for drying air, a heating means is provided in the circulation path, and the refrigerant is cooled by the heating means while the compressor is stopped. Is heated (see, for example, Patent Document 1).

  Hereinafter, a dryer equipped with the conventional clothes drying apparatus disclosed in Patent Document 1 will be described with reference to FIG. FIG. 4 is a schematic view of a conventional dryer described in Patent Document 1.

  In FIG. 4, the dryer 100 includes a drying chamber 110 for storing an object to be dried, a two-stage compression compressor 120 having an internal intermediate pressure as a compressor, a gas cooler 130 as a radiator, and an expansion valve 140 as a decompression device. An evaporator 150 as a heat absorber, a compressor 120, a gas cooler 130, an expansion valve 140, and an evaporator 150 connected in a ring shape, a refrigerant circuit 160 that uses carbon dioxide as a refrigerant, and an air circulation path 170 through which air in the drying chamber 110 circulates A turbo fan 180 is provided as an air circulation means for circulating the air, and an electric heater 190 is provided as a heating means for heating the air circulating through the air circulation path 170 at the same time as the refrigerant is heated at the start of the refrigeration cycle.

  Next, the operation of the conventional dryer will be described. When the refrigeration cycle is stopped, when the ambient temperature is low, the refrigerant is held in the refrigerant circuit 160 in a gas-liquid mixed state. Therefore, when the refrigeration cycle is started, the refrigerant is sucked into the compressor 120 in a liquid state. In other words, a so-called liquid back phenomenon occurs and the compressor 120 may be damaged. Therefore, before starting the refrigeration cycle, the turbo fan 180 and the electric heater 190 are started to warm the air in the air circulation path 170.

In the dryer of this configuration, most of the piping of the refrigerant circuit 160 is disposed so as to pass through the air circulation path 170, so that the air to be dried is preliminarily dried by heating the air with the electric heater 190. At the same time, the refrigerant in the refrigerant circuit 160 is also warmed. When the refrigerant is carbon dioxide, the internal pressure is about 4 to 7 MPa, and if the temperature is about 30 ° C. or higher, it becomes a gas. Therefore, the possibility of a liquid back phenomenon can be avoided, and at the same time, the refrigeration cycle is started. The time until the steady state is reached can be shortened.
JP 2006-116004 A

  However, the configuration of the conventional clothes drying apparatus has a problem that the cost is increased because it is necessary to include heating means such as an electric heater in addition to the heat pump apparatus.

  This invention solves the said conventional subject, and it aims at providing the clothing drying apparatus which can shorten time until a refrigerating cycle will be in a steady state, without raising a cost. is there.

  In order to solve the above-described conventional problems, the clothes drying apparatus of the present invention is reduced in pressure by a compressor, a radiator that radiates heat of the compressed refrigerant, a throttle means that reduces the pressure of the high-pressure refrigerant, and the pressure is reduced. A heat pump device configured to connect a heat sink that takes heat away from the surroundings with a pipe so that the refrigerant circulates, a refrigerant pressure detection means that detects the pressure of the refrigerant, a drying cabinet that houses clothing, A blowing means for blowing drying air, a circulation air path for guiding the drying air to the heat absorber via the radiator and the drying cabinet, and returning the air to the radiator again, and a control means for controlling the operation of the motor. And the control means controls so that the efficiency of the motor is not maximized when the refrigerant pressure detected by the refrigerant pressure detection means is lower than a predetermined value.

  Thereby, when the refrigerant pressure is low, the efficiency of the motor is set so as not to be maximized, the heat loss is increased, and the pressure is increased by heating the refrigerant with the generated heat without increasing the cost. It is possible to realize a clothes drying apparatus that can shorten the time until the refrigeration cycle reaches a steady state.

  The clothes drying apparatus of the present invention can shorten the time until the refrigeration cycle reaches a steady state without increasing the cost.

  According to a first aspect of the present invention, there is provided a compressor, a radiator that radiates heat of the compressed refrigerant, a throttle means that depressurizes the pressure of the high-pressure refrigerant, and a heat absorber that draws heat from the surroundings by the reduced-pressure refrigerant. A heat pump device configured to be connected by a pipe line so that the refrigerant circulates, a refrigerant pressure detecting means for detecting the pressure of the refrigerant, a drying chamber for storing clothes, a blowing means for blowing drying air, and the drying A circulation air passage for guiding the air to the heat absorber through the radiator and the drying cabinet and returning the air to the radiator again, and a control means for controlling the operation of the motor, the control means detecting the refrigerant pressure When the refrigerant pressure detected by the means is lower than a predetermined value, control is performed so that the efficiency of the motor is not maximized. When the refrigerant pressure is low, the efficiency of the motor is set not to be maximized. Increase heat loss, By heating the coolant raises the pressure without heat, without the cost, can refrigeration cycle to realize a clothes drying apparatus capable of shortening the time until a steady state.

  In the second invention, in particular, the control means of the first invention is configured such that when the refrigerant pressure detected by the refrigerant pressure detecting means is lower than a predetermined value, the current of the motor is increased so as to increase the amount of heat generated from the motor. The phase is controlled to a value smaller than the maximum efficiency point.When the refrigerant pressure is low, the advance angle of the phase of the motor current is set so that the motor efficiency is deteriorated to increase the heat loss. By heating and raising the pressure, it is possible to realize a clothes drying apparatus that can shorten the time until the refrigeration cycle reaches a steady state without increasing the cost.

  According to a third aspect of the present invention, in particular, when the refrigerant pressure detected by the refrigerant pressure detection unit is lower than a predetermined value, the control unit of the first aspect of the invention controls the motor current to increase the amount of heat generated from the motor. The phase is controlled to a value larger than the maximum efficiency point.When the refrigerant pressure is low, the advance angle of the phase of the motor current is set so that the motor efficiency is deteriorated to increase the heat loss. By heating and raising the pressure, it is possible to realize a clothes drying apparatus that can shorten the time until the refrigeration cycle reaches a steady state without increasing the cost.

  In the fourth invention, in particular, when the control means of any one of the first to third inventions changes the refrigerant pressure detected by the refrigerant pressure detection means from a state lower than a predetermined value to a high state. Is a control that maximizes the efficiency of the motor, shortens the time until the refrigeration cycle reaches a steady state, and realizes a clothes drying device that can efficiently drive the heat pump device during steady operation. be able to.

  In the fifth aspect of the invention, in particular, the control means of the fourth aspect of the invention is to change the current phase of the motor in a stepwise manner, so that the current phase of the motor is not changed suddenly and is stably operated. It is possible to realize a clothes drying device that can be used.

  In the sixth invention, in particular, the refrigerant pressure detecting means of any one of the first to fifth inventions is a refrigerant temperature detecting means, and the cost is increased by estimating the refrigerant pressure from the refrigerant temperature. It is possible to realize a clothes drying apparatus that can be operated stably without having

  In the seventh invention, in particular, the refrigerant pressure detecting means of any one of the first to fifth inventions is a drying air temperature detecting means, and the refrigerant pressure is estimated from the drying air temperature. Thus, it is possible to realize a clothes drying apparatus that can be stably operated without increasing the cost.

  The eighth invention is a washing / drying machine provided with the clothes drying device of any one of the first to seventh inventions, and shortens the time until the refrigeration cycle reaches a steady state without increasing the cost. Therefore, drying time can be shortened.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the present embodiment.

(Embodiment 1)
FIG. 1 is a perspective view of a washing / drying machine equipped with a clothes drying apparatus according to a first embodiment of the present invention as seen from the back, and FIG. 2 is a side sectional view of the washing / drying machine. In FIG. 1, a washing tub 26 is provided in a washing / drying machine main body 25 (hereinafter referred to as “main body 25”) of the washing / drying machine according to the present embodiment, and a drum motor 27 is attached thereto. The washing tub 26 is attached to the main body 25 by being supported by suspensions 29 on both sides and an upper suspension 30.

  The main body 25 includes a compressor 35 that compresses the vaporized refrigerant, a radiator 36 that radiates heat of the compressed high-temperature and high-pressure refrigerant, an expansion valve for reducing the pressure of the high-pressure refrigerant, or a capillary tube. And a heat pump device constructed by connecting a throttling means 37 and a heat absorber 38, in which the reduced pressure and low pressure refrigerant removes heat from the surroundings, and connecting them by a conduit 39 so that the refrigerant circulates again to the compressor 35. 51. The compressor 35 includes a motor (not shown).

  The air passage 40 is configured to communicate the heat absorber 38 as a dehumidifying means for cooling the drying air and the radiator 36 as a heating means for heating the drying air. The washing tub 26 and the air passage 40 are connected by flexible hoses 41 and 42. The air passage 40 is provided with air blowing means 43. A duct 44 that communicates the inside of the washing tub 26 and the flexible hose 41 is provided on the outer wall of the washing tub 26. As described above, a circulation air passage 53 through which dry air circulates is formed by the flexible hose 42, the washing tub 26 that houses the rotating drum 28 described later, the duct 44, the flexible hose 41, and the air passage 40. Yes. An arrow B indicates the flow of drying air in the duct 44 and the air passage 40.

  In FIG. 2, a rotating drum 28 serving as a drying cabinet for storing clothes 31 is directly connected to a shaft 27 a of a drum motor 27 and is rotatably mounted in the washing tub 26. A door 32 for loading clothes 31 is provided at a position corresponding to the front opening of the washing tub 26 and the rotary drum 28. A gap between the main body 25 and the washing tub 26 is substantially sealed by a bellows 33 and a door packing 34 so that air does not leak into the main body 25 or outside the machine. A plurality of holes 45 and openings 46 through which washing water and drying air enter and exit are provided on the side wall and bottom of the rotating drum 28. The opening 56 is provided on the inner wall of the washing tub 26 and communicates the air path between the washing tub 26 and the duct 44. An arrow C indicates the flow of drying air in the washing tub 26 and the rotary drum 28.

  The washing drainage channel 47 is a channel for draining wastewater during washing. Condensed water generated in the heat absorber 38 during drying is received in a water reservoir 67. One end of a condensation drainage channel 48 having a pump 68 is connected to the bottom 69 of the water reservoir 67, and the other end of the condensation drainage channel 48 and the washing drainage channel 47 are connected to one drainage pipe 49.

  The tip 50 of the drain pipe 49 is open to the atmosphere outside the machine. One drain valve 60 is provided in the washing drain channel 47 to control drainage from the washing tub. The condensation drainage channel 48 merges with the washing drainage channel 47 on the downstream side of the drainage valve 60, and the drainage of the condensed water is controlled only by the pump 68.

  The refrigerant temperature detecting means 71 is provided close to the pipe line 39 between the compressor 35 and the inlet of the radiator 36, and detects the temperature of the refrigerant. The drying air temperature detection means 72 is installed in the circulation air passage 53 and detects the temperature of the drying air. The control means 73 controls the operation of the motor included in the compressor 35.

  The operation and action of the washing / drying machine configured as described above will be described below. In the washing process from washing, rinsing and dehydration, when water is collected, the drainage valve 60 closes the washing drainage channel 47 side, and water is supplied to the washing tub 26 from a water supply valve (not shown). Water is accumulated up to the position of the water level D.

  The rotating drum 28 rotates continuously or intermittently at a programmed number of rotations, and cleaning and rinsing are performed. During this time, the clothes 31 are lifted and dropped by the rotation of the rotary drum 28. When draining, the drainage valve 60 opens the washing drainage channel 47 side, and the water in the washing tub 14 passes through the washing drainage channel 47 and the drainage valve 60 and is drained out of the machine from the drainage pipe 49.

  In the drying process, the washing drainage channel 47 side is closed by the drain valve 60, and the motor 27 that drives the compressor 35, the blowing means 43, and the rotary drum 28 is operated. By the operation of the blowing means 43, the drying air circulates through the inside of the washing tub 26, the duct 44, the flexible hose 41, the air path 40, and the flexible hose 42. The clothing 31 is agitated by a rotating drum 28 that rotates continuously or intermittently at a preset number of rotations.

  By the operation of the compressor 35, the refrigerant circulates in the pipe 39, and the heat of the high-temperature and high-pressure refrigerant is radiated by the radiator 36 to heat the drying air. The heated drying air is sent into the washing tub 26 as shown by an arrow C in FIG. 2, passes through the opening 46 provided in the bottom surface of the rotary drum 28, hits the clothing 31, and removes moisture from the clothing 31. The air is then taken as humid air, passes through a large number of holes 45 provided in the side wall of the rotary drum 28, and is sent to the duct 44 through the opening 56 of the washing tub 26. The drying air that has passed through the duct 44 passes through the flexible hose 41 and is dehumidified by a heat absorber 38 as a dehumidifying means provided in the air passage 40 as indicated by an arrow B. The dehumidified drying air is sent again to the radiator 36 by the blowing means 43 and heated.

  During the drying operation, the motor operation is controlled by the control means 73 so that the temperature of the drying air becomes constant at the predetermined temperature T.

  When the drying operation is started in a state in which the main body 25 is adapted to the room temperature, the heat pump device 51 is also at the room temperature. Therefore, the refrigerant is heated by the electric power input to the motor included in the compressor 35, and the energy is based on the energy. The drying air is heated. However, if the temperature of the refrigerant is low, the pressure of the refrigerant is also low, so that the motor requires less torque, and the input power is also reduced.

  For this reason, even when used at normal room temperature, the time required to heat the drying air to a desired temperature is longer than when heating with a heater. Moreover, when the atmospheric temperature of the main body 25 is low, such as in winter, a longer time is required.

  In order to improve this, the current phase of the motor is appropriately controlled. The current phase of the motor represents the current application timing with respect to the position of the rotor. Here, as shown in FIG. 3, the motor loss can be expressed as a function of the current phase. When the motor loss is reduced, the electric power used for the rotation of the motor in the input electric power is increased, so that the motor efficiency is increased. Therefore, the point with the smallest motor loss is called the maximum efficiency point. At the maximum efficiency point, the motor efficiency is highest at the same output torque. The motor loss at this time is Lmin. Considering the case where the current phase value is zero, for example, other than the maximum efficiency point, more motor loss La occurs than the maximum efficiency point at the same output torque.

  Since motor loss is converted into heat inside the motor, when controlling a normal motor, the amount of heat generated here is released to the atmosphere and literally becomes a loss, but in the case of a motor contained in a compressor, The amount of heat is used to raise the temperature of the refrigerant because the refrigerant collects it.

  Thereby, since the time until the temperature of the drying air reaches the predetermined temperature T is shortened, the drying operation time is shortened as a whole.

  Further, after the temperature of the drying air reaches the predetermined temperature T, the rotation speed of the motor is controlled so as to keep the temperature constant. For example, when rotating at a certain rotation speed R, if the temperature of the drying air becomes higher than the predetermined temperature T, the rotation speed is lowered, and conversely, the temperature of the drying air becomes lower than the predetermined temperature T. Is a control to increase the rotational speed. Here, considering the motor loss described above, the motor loss is converted into heat by the motor and heats the refrigerant, and as a result, heats the drying air. According to the above control, the motor loss contributes to a decrease in the rotational speed. .

  In a drying system using a heat pump, the heat absorption amount of the heat absorber 38 increases and the drying capacity increases as the rotational speed of the motor increases. Therefore, the drying capacity increases as the amount of heat generated from the motor decreases. Therefore, after the temperature of the drying air reaches the predetermined temperature T, the drying operation time can be further shortened by setting the motor current phase to the maximum efficiency point in order to minimize motor loss.

  When the current phase is changed (in the case of the present embodiment, from zero to the maximum efficiency point), if the change is made in a short time, the motor may step out and the operation of the compressor 35 may be stopped. The change in this case may be performed step by step, and the current phase may be controlled to approach the maximum efficiency point T as the temperature of the drying air rises and approaches the predetermined temperature T.

  As described above, according to the present embodiment, when the temperature of the drying air detected by the drying air temperature detection means 72 is lower than the predetermined temperature T, heat is generated from the motor contained in the compressor 35. By controlling the motor current phase to a value smaller than the maximum efficiency point so as to increase the amount, when the temperature of the drying air is low, the advance angle of the motor current phase is set so that the motor efficiency is deteriorated. By increasing the motor loss and heating the refrigerant with the generated heat and consequently heating the drying air, it is possible to shorten the time until the refrigeration cycle reaches a steady state without increasing the cost. A clothes drying apparatus can be provided.

  In this embodiment, the temperature of the drying air is detected and controlled to be constant at the predetermined temperature T. However, since the temperature of the drying air and the temperature of the refrigerant are highly correlated, Even if the temperature is detected and controlled to be constant at the second predetermined temperature T2, the same effect can be obtained.

  Further, since the temperature of the refrigerant is highly correlated with the refrigerant pressure, the refrigerant pressure detecting means can be configured easily and inexpensively using the drying air temperature detecting means 72 and the refrigerant temperature detecting means 71.

  Further, in the present embodiment, in order to increase the motor loss, the advance angle of the current phase at the initial stage of the drying operation is controlled to zero, but as is clear from FIG. 3, a point exceeding the maximum efficiency point, for example, It goes without saying that the same effect can be obtained by setting 60.

  Moreover, in the said embodiment, although the tube type heat exchanger with a plate fin is shown as a heat exchanger which forms the heat radiator 36 and the heat absorber 38, the form is not specifically limited.

  In the present embodiment, the washing / drying machine has been described as an example, but it goes without saying that the same effect can be obtained even in a clothes drying machine that only dries clothes.

  As described above, the clothes drying apparatus according to the present invention can reduce the time until the refrigeration cycle reaches a steady state without increasing the cost. It can be widely applied to a washing machine with a drying function performed in the same tank and a clothes dryer performing only drying.

The perspective view which looked at the washing-drying machine carrying the clothing drying apparatus in the 1st Embodiment of this invention from the back Side sectional view of the washer / dryer Characteristic diagram of motor loss of the motor contained in the compressor mounted on the washer / dryer Schematic diagram of a washing dryer equipped with a conventional clothes dryer

Explanation of symbols

26 Laundry tub 28 Rotating drum (dryer)
31 Clothing 35 Compressor 36 Radiator 37 Throttle means 38 Heat absorber 39 Pipe line 40 Air path 43 Air blow means 51 Heat pump device 53 Circulation air path 71 Refrigerant temperature detection means 72 Drying air temperature detection means 73 Control means

Claims (8)

A motor, a compressor driven by the motor, a radiator that dissipates the heat of the compressed refrigerant, a throttle means that depressurizes the pressure of the high-pressure refrigerant, and an endothermic that draws heat from the surroundings by the reduced-pressure refrigerant. A heat pump device configured by connecting a pipe with a pipe so that the refrigerant circulates, a refrigerant pressure detecting means for detecting the pressure of the refrigerant, a drying chamber for storing clothing, and a blowing means for blowing drying air A circulation air passage that guides the drying air to the heat absorber through the radiator and the drying cabinet and returns the air to the heat radiator, and a control unit that controls the operation of the motor. A clothes drying apparatus, wherein the efficiency of the motor is controlled so as not to become maximum when the refrigerant pressure detected by the refrigerant pressure detecting means is lower than a predetermined value. The clothes drying method according to claim 1, wherein the control means controls the current phase of the motor to a value smaller than a maximum efficiency point when the refrigerant pressure detected by the refrigerant pressure detection means is lower than a predetermined value. apparatus. The clothes drying method according to claim 1, wherein the control means controls the current phase of the motor to a value larger than a maximum efficiency point when the refrigerant pressure detected by the refrigerant pressure detection means is lower than a predetermined value. apparatus. The control means controls so that the efficiency of the motor is maximized when the refrigerant pressure detected by the refrigerant pressure detection means transits from a state lower than a predetermined value to a high state. The clothing drying apparatus according to any one of 1 to 3. The clothes drying apparatus according to claim 4, wherein the control means changes the current phase of the motor stepwise. The clothes drying apparatus according to any one of claims 1 to 5, wherein the refrigerant pressure detection means is a refrigerant temperature detection means. The clothes drying apparatus according to any one of claims 1 to 5, wherein the refrigerant pressure detection means is a drying air temperature detection means. A washing and drying machine comprising the clothes drying apparatus according to any one of claims 1 to 7.